mirror of
https://github.com/c64scene-ar/llvm-6502.git
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git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@11149 91177308-0d34-0410-b5e6-96231b3b80d8
2676 lines
80 KiB
C
2676 lines
80 KiB
C
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/* pngwutil.c - utilities to write a PNG file
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*
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* libpng 1.2.5 - October 3, 2002
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* For conditions of distribution and use, see copyright notice in png.h
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* Copyright (c) 1998-2002 Glenn Randers-Pehrson
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* (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
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* (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.)
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*/
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#define PNG_INTERNAL
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#include "png.h"
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#ifdef PNG_WRITE_SUPPORTED
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/* Place a 32-bit number into a buffer in PNG byte order. We work
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* with unsigned numbers for convenience, although one supported
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* ancillary chunk uses signed (two's complement) numbers.
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*/
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void /* PRIVATE */
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png_save_uint_32(png_bytep buf, png_uint_32 i)
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{
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buf[0] = (png_byte)((i >> 24) & 0xff);
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buf[1] = (png_byte)((i >> 16) & 0xff);
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buf[2] = (png_byte)((i >> 8) & 0xff);
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buf[3] = (png_byte)(i & 0xff);
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}
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#if defined(PNG_WRITE_pCAL_SUPPORTED) || defined(PNG_WRITE_oFFs_SUPPORTED)
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/* The png_save_int_32 function assumes integers are stored in two's
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* complement format. If this isn't the case, then this routine needs to
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* be modified to write data in two's complement format.
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*/
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void /* PRIVATE */
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png_save_int_32(png_bytep buf, png_int_32 i)
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{
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buf[0] = (png_byte)((i >> 24) & 0xff);
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buf[1] = (png_byte)((i >> 16) & 0xff);
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buf[2] = (png_byte)((i >> 8) & 0xff);
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buf[3] = (png_byte)(i & 0xff);
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}
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#endif
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/* Place a 16-bit number into a buffer in PNG byte order.
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* The parameter is declared unsigned int, not png_uint_16,
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* just to avoid potential problems on pre-ANSI C compilers.
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*/
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void /* PRIVATE */
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png_save_uint_16(png_bytep buf, unsigned int i)
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{
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buf[0] = (png_byte)((i >> 8) & 0xff);
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buf[1] = (png_byte)(i & 0xff);
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}
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/* Write a PNG chunk all at once. The type is an array of ASCII characters
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* representing the chunk name. The array must be at least 4 bytes in
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* length, and does not need to be null terminated. To be safe, pass the
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* pre-defined chunk names here, and if you need a new one, define it
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* where the others are defined. The length is the length of the data.
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* All the data must be present. If that is not possible, use the
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* png_write_chunk_start(), png_write_chunk_data(), and png_write_chunk_end()
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* functions instead.
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*/
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void PNGAPI
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png_write_chunk(png_structp png_ptr, png_bytep chunk_name,
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png_bytep data, png_size_t length)
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{
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png_write_chunk_start(png_ptr, chunk_name, (png_uint_32)length);
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png_write_chunk_data(png_ptr, data, length);
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png_write_chunk_end(png_ptr);
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}
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/* Write the start of a PNG chunk. The type is the chunk type.
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* The total_length is the sum of the lengths of all the data you will be
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* passing in png_write_chunk_data().
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*/
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void PNGAPI
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png_write_chunk_start(png_structp png_ptr, png_bytep chunk_name,
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png_uint_32 length)
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{
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png_byte buf[4];
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png_debug2(0, "Writing %s chunk (%lu bytes)\n", chunk_name, length);
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/* write the length */
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png_save_uint_32(buf, length);
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png_write_data(png_ptr, buf, (png_size_t)4);
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/* write the chunk name */
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png_write_data(png_ptr, chunk_name, (png_size_t)4);
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/* reset the crc and run it over the chunk name */
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png_reset_crc(png_ptr);
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png_calculate_crc(png_ptr, chunk_name, (png_size_t)4);
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}
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/* Write the data of a PNG chunk started with png_write_chunk_start().
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* Note that multiple calls to this function are allowed, and that the
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* sum of the lengths from these calls *must* add up to the total_length
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* given to png_write_chunk_start().
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*/
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void PNGAPI
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png_write_chunk_data(png_structp png_ptr, png_bytep data, png_size_t length)
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{
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/* write the data, and run the CRC over it */
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if (data != NULL && length > 0)
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{
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png_calculate_crc(png_ptr, data, length);
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png_write_data(png_ptr, data, length);
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}
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}
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/* Finish a chunk started with png_write_chunk_start(). */
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void PNGAPI
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png_write_chunk_end(png_structp png_ptr)
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{
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png_byte buf[4];
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/* write the crc */
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png_save_uint_32(buf, png_ptr->crc);
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png_write_data(png_ptr, buf, (png_size_t)4);
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}
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/* Simple function to write the signature. If we have already written
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* the magic bytes of the signature, or more likely, the PNG stream is
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* being embedded into another stream and doesn't need its own signature,
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* we should call png_set_sig_bytes() to tell libpng how many of the
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* bytes have already been written.
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*/
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void /* PRIVATE */
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png_write_sig(png_structp png_ptr)
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{
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png_byte png_signature[8] = {137, 80, 78, 71, 13, 10, 26, 10};
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/* write the rest of the 8 byte signature */
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png_write_data(png_ptr, &png_signature[png_ptr->sig_bytes],
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(png_size_t)8 - png_ptr->sig_bytes);
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if(png_ptr->sig_bytes < 3)
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png_ptr->mode |= PNG_HAVE_PNG_SIGNATURE;
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}
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#if defined(PNG_WRITE_TEXT_SUPPORTED) || defined(PNG_WRITE_iCCP_SUPPORTED)
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/*
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* This pair of functions encapsulates the operation of (a) compressing a
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* text string, and (b) issuing it later as a series of chunk data writes.
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* The compression_state structure is shared context for these functions
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* set up by the caller in order to make the whole mess thread-safe.
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*/
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typedef struct
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{
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char *input; /* the uncompressed input data */
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int input_len; /* its length */
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int num_output_ptr; /* number of output pointers used */
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int max_output_ptr; /* size of output_ptr */
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png_charpp output_ptr; /* array of pointers to output */
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} compression_state;
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/* compress given text into storage in the png_ptr structure */
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static int /* PRIVATE */
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png_text_compress(png_structp png_ptr,
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png_charp text, png_size_t text_len, int compression,
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compression_state *comp)
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{
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int ret;
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comp->num_output_ptr = comp->max_output_ptr = 0;
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comp->output_ptr = NULL;
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comp->input = NULL;
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/* we may just want to pass the text right through */
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if (compression == PNG_TEXT_COMPRESSION_NONE)
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{
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comp->input = text;
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comp->input_len = text_len;
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return((int)text_len);
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}
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if (compression >= PNG_TEXT_COMPRESSION_LAST)
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{
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#if !defined(PNG_NO_STDIO) && !defined(_WIN32_WCE)
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char msg[50];
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sprintf(msg, "Unknown compression type %d", compression);
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png_warning(png_ptr, msg);
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#else
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png_warning(png_ptr, "Unknown compression type");
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#endif
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}
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/* We can't write the chunk until we find out how much data we have,
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* which means we need to run the compressor first and save the
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* output. This shouldn't be a problem, as the vast majority of
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* comments should be reasonable, but we will set up an array of
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* malloc'd pointers to be sure.
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*
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* If we knew the application was well behaved, we could simplify this
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* greatly by assuming we can always malloc an output buffer large
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* enough to hold the compressed text ((1001 * text_len / 1000) + 12)
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* and malloc this directly. The only time this would be a bad idea is
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* if we can't malloc more than 64K and we have 64K of random input
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* data, or if the input string is incredibly large (although this
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* wouldn't cause a failure, just a slowdown due to swapping).
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*/
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/* set up the compression buffers */
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png_ptr->zstream.avail_in = (uInt)text_len;
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png_ptr->zstream.next_in = (Bytef *)text;
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png_ptr->zstream.avail_out = (uInt)png_ptr->zbuf_size;
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png_ptr->zstream.next_out = (Bytef *)png_ptr->zbuf;
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/* this is the same compression loop as in png_write_row() */
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do
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{
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/* compress the data */
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ret = deflate(&png_ptr->zstream, Z_NO_FLUSH);
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if (ret != Z_OK)
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{
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/* error */
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if (png_ptr->zstream.msg != NULL)
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png_error(png_ptr, png_ptr->zstream.msg);
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else
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png_error(png_ptr, "zlib error");
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}
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/* check to see if we need more room */
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if (!png_ptr->zstream.avail_out && png_ptr->zstream.avail_in)
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{
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/* make sure the output array has room */
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if (comp->num_output_ptr >= comp->max_output_ptr)
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{
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int old_max;
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old_max = comp->max_output_ptr;
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comp->max_output_ptr = comp->num_output_ptr + 4;
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if (comp->output_ptr != NULL)
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{
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png_charpp old_ptr;
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old_ptr = comp->output_ptr;
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comp->output_ptr = (png_charpp)png_malloc(png_ptr,
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(png_uint_32)(comp->max_output_ptr * sizeof (png_charpp)));
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png_memcpy(comp->output_ptr, old_ptr, old_max
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* sizeof (png_charp));
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png_free(png_ptr, old_ptr);
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}
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else
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comp->output_ptr = (png_charpp)png_malloc(png_ptr,
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(png_uint_32)(comp->max_output_ptr * sizeof (png_charp)));
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}
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/* save the data */
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comp->output_ptr[comp->num_output_ptr] = (png_charp)png_malloc(png_ptr,
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(png_uint_32)png_ptr->zbuf_size);
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png_memcpy(comp->output_ptr[comp->num_output_ptr], png_ptr->zbuf,
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png_ptr->zbuf_size);
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comp->num_output_ptr++;
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/* and reset the buffer */
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png_ptr->zstream.avail_out = (uInt)png_ptr->zbuf_size;
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png_ptr->zstream.next_out = png_ptr->zbuf;
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}
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/* continue until we don't have any more to compress */
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} while (png_ptr->zstream.avail_in);
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/* finish the compression */
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do
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{
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/* tell zlib we are finished */
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ret = deflate(&png_ptr->zstream, Z_FINISH);
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if (ret == Z_OK)
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{
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/* check to see if we need more room */
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if (!(png_ptr->zstream.avail_out))
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{
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/* check to make sure our output array has room */
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if (comp->num_output_ptr >= comp->max_output_ptr)
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{
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int old_max;
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old_max = comp->max_output_ptr;
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comp->max_output_ptr = comp->num_output_ptr + 4;
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if (comp->output_ptr != NULL)
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{
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png_charpp old_ptr;
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old_ptr = comp->output_ptr;
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/* This could be optimized to realloc() */
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comp->output_ptr = (png_charpp)png_malloc(png_ptr,
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(png_uint_32)(comp->max_output_ptr * sizeof (png_charpp)));
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png_memcpy(comp->output_ptr, old_ptr,
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old_max * sizeof (png_charp));
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png_free(png_ptr, old_ptr);
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}
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else
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comp->output_ptr = (png_charpp)png_malloc(png_ptr,
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(png_uint_32)(comp->max_output_ptr * sizeof (png_charp)));
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}
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/* save off the data */
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comp->output_ptr[comp->num_output_ptr] =
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(png_charp)png_malloc(png_ptr, (png_uint_32)png_ptr->zbuf_size);
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png_memcpy(comp->output_ptr[comp->num_output_ptr], png_ptr->zbuf,
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png_ptr->zbuf_size);
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comp->num_output_ptr++;
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/* and reset the buffer pointers */
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png_ptr->zstream.avail_out = (uInt)png_ptr->zbuf_size;
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png_ptr->zstream.next_out = png_ptr->zbuf;
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}
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}
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else if (ret != Z_STREAM_END)
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{
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/* we got an error */
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if (png_ptr->zstream.msg != NULL)
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png_error(png_ptr, png_ptr->zstream.msg);
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else
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png_error(png_ptr, "zlib error");
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}
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} while (ret != Z_STREAM_END);
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/* text length is number of buffers plus last buffer */
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text_len = png_ptr->zbuf_size * comp->num_output_ptr;
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if (png_ptr->zstream.avail_out < png_ptr->zbuf_size)
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text_len += png_ptr->zbuf_size - (png_size_t)png_ptr->zstream.avail_out;
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return((int)text_len);
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}
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/* ship the compressed text out via chunk writes */
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static void /* PRIVATE */
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png_write_compressed_data_out(png_structp png_ptr, compression_state *comp)
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{
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int i;
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/* handle the no-compression case */
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if (comp->input)
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{
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png_write_chunk_data(png_ptr, (png_bytep)comp->input,
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(png_size_t)comp->input_len);
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return;
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}
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/* write saved output buffers, if any */
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for (i = 0; i < comp->num_output_ptr; i++)
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{
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png_write_chunk_data(png_ptr,(png_bytep)comp->output_ptr[i],
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png_ptr->zbuf_size);
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png_free(png_ptr, comp->output_ptr[i]);
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comp->output_ptr[i]=NULL;
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}
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if (comp->max_output_ptr != 0)
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png_free(png_ptr, comp->output_ptr);
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comp->output_ptr=NULL;
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/* write anything left in zbuf */
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if (png_ptr->zstream.avail_out < (png_uint_32)png_ptr->zbuf_size)
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png_write_chunk_data(png_ptr, png_ptr->zbuf,
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png_ptr->zbuf_size - png_ptr->zstream.avail_out);
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/* reset zlib for another zTXt/iTXt or the image data */
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deflateReset(&png_ptr->zstream);
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}
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#endif
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/* Write the IHDR chunk, and update the png_struct with the necessary
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* information. Note that the rest of this code depends upon this
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* information being correct.
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*/
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void /* PRIVATE */
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png_write_IHDR(png_structp png_ptr, png_uint_32 width, png_uint_32 height,
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int bit_depth, int color_type, int compression_type, int filter_type,
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int interlace_type)
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{
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#ifdef PNG_USE_LOCAL_ARRAYS
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PNG_IHDR;
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#endif
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png_byte buf[13]; /* buffer to store the IHDR info */
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png_debug(1, "in png_write_IHDR\n");
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/* Check that we have valid input data from the application info */
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switch (color_type)
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{
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case PNG_COLOR_TYPE_GRAY:
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switch (bit_depth)
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{
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case 1:
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case 2:
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case 4:
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case 8:
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case 16: png_ptr->channels = 1; break;
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default: png_error(png_ptr,"Invalid bit depth for grayscale image");
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}
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break;
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case PNG_COLOR_TYPE_RGB:
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if (bit_depth != 8 && bit_depth != 16)
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png_error(png_ptr, "Invalid bit depth for RGB image");
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png_ptr->channels = 3;
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break;
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case PNG_COLOR_TYPE_PALETTE:
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switch (bit_depth)
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{
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case 1:
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case 2:
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case 4:
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case 8: png_ptr->channels = 1; break;
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default: png_error(png_ptr, "Invalid bit depth for paletted image");
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}
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break;
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case PNG_COLOR_TYPE_GRAY_ALPHA:
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if (bit_depth != 8 && bit_depth != 16)
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png_error(png_ptr, "Invalid bit depth for grayscale+alpha image");
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png_ptr->channels = 2;
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break;
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case PNG_COLOR_TYPE_RGB_ALPHA:
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if (bit_depth != 8 && bit_depth != 16)
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png_error(png_ptr, "Invalid bit depth for RGBA image");
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png_ptr->channels = 4;
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break;
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default:
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png_error(png_ptr, "Invalid image color type specified");
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}
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if (compression_type != PNG_COMPRESSION_TYPE_BASE)
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{
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png_warning(png_ptr, "Invalid compression type specified");
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compression_type = PNG_COMPRESSION_TYPE_BASE;
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}
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/* Write filter_method 64 (intrapixel differencing) only if
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* 1. Libpng was compiled with PNG_MNG_FEATURES_SUPPORTED and
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* 2. Libpng did not write a PNG signature (this filter_method is only
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* used in PNG datastreams that are embedded in MNG datastreams) and
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* 3. The application called png_permit_mng_features with a mask that
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* included PNG_FLAG_MNG_FILTER_64 and
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* 4. The filter_method is 64 and
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* 5. The color_type is RGB or RGBA
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*/
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if (
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#if defined(PNG_MNG_FEATURES_SUPPORTED)
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!((png_ptr->mng_features_permitted & PNG_FLAG_MNG_FILTER_64) &&
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((png_ptr->mode&PNG_HAVE_PNG_SIGNATURE) == 0) &&
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(color_type == PNG_COLOR_TYPE_RGB ||
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color_type == PNG_COLOR_TYPE_RGB_ALPHA) &&
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(filter_type == PNG_INTRAPIXEL_DIFFERENCING)) &&
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#endif
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filter_type != PNG_FILTER_TYPE_BASE)
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{
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png_warning(png_ptr, "Invalid filter type specified");
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filter_type = PNG_FILTER_TYPE_BASE;
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}
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#ifdef PNG_WRITE_INTERLACING_SUPPORTED
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if (interlace_type != PNG_INTERLACE_NONE &&
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interlace_type != PNG_INTERLACE_ADAM7)
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{
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png_warning(png_ptr, "Invalid interlace type specified");
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interlace_type = PNG_INTERLACE_ADAM7;
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}
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#else
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interlace_type=PNG_INTERLACE_NONE;
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#endif
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/* save off the relevent information */
|
|
png_ptr->bit_depth = (png_byte)bit_depth;
|
|
png_ptr->color_type = (png_byte)color_type;
|
|
png_ptr->interlaced = (png_byte)interlace_type;
|
|
#if defined(PNG_MNG_FEATURES_SUPPORTED)
|
|
png_ptr->filter_type = (png_byte)filter_type;
|
|
#endif
|
|
png_ptr->width = width;
|
|
png_ptr->height = height;
|
|
|
|
png_ptr->pixel_depth = (png_byte)(bit_depth * png_ptr->channels);
|
|
png_ptr->rowbytes = ((width * (png_size_t)png_ptr->pixel_depth + 7) >> 3);
|
|
/* set the usr info, so any transformations can modify it */
|
|
png_ptr->usr_width = png_ptr->width;
|
|
png_ptr->usr_bit_depth = png_ptr->bit_depth;
|
|
png_ptr->usr_channels = png_ptr->channels;
|
|
|
|
/* pack the header information into the buffer */
|
|
png_save_uint_32(buf, width);
|
|
png_save_uint_32(buf + 4, height);
|
|
buf[8] = (png_byte)bit_depth;
|
|
buf[9] = (png_byte)color_type;
|
|
buf[10] = (png_byte)compression_type;
|
|
buf[11] = (png_byte)filter_type;
|
|
buf[12] = (png_byte)interlace_type;
|
|
|
|
/* write the chunk */
|
|
png_write_chunk(png_ptr, (png_bytep)png_IHDR, buf, (png_size_t)13);
|
|
|
|
/* initialize zlib with PNG info */
|
|
png_ptr->zstream.zalloc = png_zalloc;
|
|
png_ptr->zstream.zfree = png_zfree;
|
|
png_ptr->zstream.opaque = (voidpf)png_ptr;
|
|
if (!(png_ptr->do_filter))
|
|
{
|
|
if (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE ||
|
|
png_ptr->bit_depth < 8)
|
|
png_ptr->do_filter = PNG_FILTER_NONE;
|
|
else
|
|
png_ptr->do_filter = PNG_ALL_FILTERS;
|
|
}
|
|
if (!(png_ptr->flags & PNG_FLAG_ZLIB_CUSTOM_STRATEGY))
|
|
{
|
|
if (png_ptr->do_filter != PNG_FILTER_NONE)
|
|
png_ptr->zlib_strategy = Z_FILTERED;
|
|
else
|
|
png_ptr->zlib_strategy = Z_DEFAULT_STRATEGY;
|
|
}
|
|
if (!(png_ptr->flags & PNG_FLAG_ZLIB_CUSTOM_LEVEL))
|
|
png_ptr->zlib_level = Z_DEFAULT_COMPRESSION;
|
|
if (!(png_ptr->flags & PNG_FLAG_ZLIB_CUSTOM_MEM_LEVEL))
|
|
png_ptr->zlib_mem_level = 8;
|
|
if (!(png_ptr->flags & PNG_FLAG_ZLIB_CUSTOM_WINDOW_BITS))
|
|
png_ptr->zlib_window_bits = 15;
|
|
if (!(png_ptr->flags & PNG_FLAG_ZLIB_CUSTOM_METHOD))
|
|
png_ptr->zlib_method = 8;
|
|
deflateInit2(&png_ptr->zstream, png_ptr->zlib_level,
|
|
png_ptr->zlib_method, png_ptr->zlib_window_bits,
|
|
png_ptr->zlib_mem_level, png_ptr->zlib_strategy);
|
|
png_ptr->zstream.next_out = png_ptr->zbuf;
|
|
png_ptr->zstream.avail_out = (uInt)png_ptr->zbuf_size;
|
|
|
|
png_ptr->mode = PNG_HAVE_IHDR;
|
|
}
|
|
|
|
/* write the palette. We are careful not to trust png_color to be in the
|
|
* correct order for PNG, so people can redefine it to any convenient
|
|
* structure.
|
|
*/
|
|
void /* PRIVATE */
|
|
png_write_PLTE(png_structp png_ptr, png_colorp palette, png_uint_32 num_pal)
|
|
{
|
|
#ifdef PNG_USE_LOCAL_ARRAYS
|
|
PNG_PLTE;
|
|
#endif
|
|
png_uint_32 i;
|
|
png_colorp pal_ptr;
|
|
png_byte buf[3];
|
|
|
|
png_debug(1, "in png_write_PLTE\n");
|
|
if ((
|
|
#if defined(PNG_MNG_FEATURES_SUPPORTED)
|
|
!(png_ptr->mng_features_permitted & PNG_FLAG_MNG_EMPTY_PLTE) &&
|
|
#endif
|
|
num_pal == 0) || num_pal > 256)
|
|
{
|
|
if (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE)
|
|
{
|
|
png_error(png_ptr, "Invalid number of colors in palette");
|
|
}
|
|
else
|
|
{
|
|
png_warning(png_ptr, "Invalid number of colors in palette");
|
|
return;
|
|
}
|
|
}
|
|
|
|
if (!(png_ptr->color_type&PNG_COLOR_MASK_COLOR))
|
|
{
|
|
png_warning(png_ptr,
|
|
"Ignoring request to write a PLTE chunk in grayscale PNG");
|
|
return;
|
|
}
|
|
|
|
png_ptr->num_palette = (png_uint_16)num_pal;
|
|
png_debug1(3, "num_palette = %d\n", png_ptr->num_palette);
|
|
|
|
png_write_chunk_start(png_ptr, (png_bytep)png_PLTE, num_pal * 3);
|
|
#ifndef PNG_NO_POINTER_INDEXING
|
|
for (i = 0, pal_ptr = palette; i < num_pal; i++, pal_ptr++)
|
|
{
|
|
buf[0] = pal_ptr->red;
|
|
buf[1] = pal_ptr->green;
|
|
buf[2] = pal_ptr->blue;
|
|
png_write_chunk_data(png_ptr, buf, (png_size_t)3);
|
|
}
|
|
#else
|
|
/* This is a little slower but some buggy compilers need to do this instead */
|
|
pal_ptr=palette;
|
|
for (i = 0; i < num_pal; i++)
|
|
{
|
|
buf[0] = pal_ptr[i].red;
|
|
buf[1] = pal_ptr[i].green;
|
|
buf[2] = pal_ptr[i].blue;
|
|
png_write_chunk_data(png_ptr, buf, (png_size_t)3);
|
|
}
|
|
#endif
|
|
png_write_chunk_end(png_ptr);
|
|
png_ptr->mode |= PNG_HAVE_PLTE;
|
|
}
|
|
|
|
/* write an IDAT chunk */
|
|
void /* PRIVATE */
|
|
png_write_IDAT(png_structp png_ptr, png_bytep data, png_size_t length)
|
|
{
|
|
#ifdef PNG_USE_LOCAL_ARRAYS
|
|
PNG_IDAT;
|
|
#endif
|
|
png_debug(1, "in png_write_IDAT\n");
|
|
png_write_chunk(png_ptr, (png_bytep)png_IDAT, data, length);
|
|
png_ptr->mode |= PNG_HAVE_IDAT;
|
|
}
|
|
|
|
/* write an IEND chunk */
|
|
void /* PRIVATE */
|
|
png_write_IEND(png_structp png_ptr)
|
|
{
|
|
#ifdef PNG_USE_LOCAL_ARRAYS
|
|
PNG_IEND;
|
|
#endif
|
|
png_debug(1, "in png_write_IEND\n");
|
|
png_write_chunk(png_ptr, (png_bytep)png_IEND, png_bytep_NULL,
|
|
(png_size_t)0);
|
|
png_ptr->mode |= PNG_HAVE_IEND;
|
|
}
|
|
|
|
#if defined(PNG_WRITE_gAMA_SUPPORTED)
|
|
/* write a gAMA chunk */
|
|
#ifdef PNG_FLOATING_POINT_SUPPORTED
|
|
void /* PRIVATE */
|
|
png_write_gAMA(png_structp png_ptr, double file_gamma)
|
|
{
|
|
#ifdef PNG_USE_LOCAL_ARRAYS
|
|
PNG_gAMA;
|
|
#endif
|
|
png_uint_32 igamma;
|
|
png_byte buf[4];
|
|
|
|
png_debug(1, "in png_write_gAMA\n");
|
|
/* file_gamma is saved in 1/100,000ths */
|
|
igamma = (png_uint_32)(file_gamma * 100000.0 + 0.5);
|
|
png_save_uint_32(buf, igamma);
|
|
png_write_chunk(png_ptr, (png_bytep)png_gAMA, buf, (png_size_t)4);
|
|
}
|
|
#endif
|
|
#ifdef PNG_FIXED_POINT_SUPPORTED
|
|
void /* PRIVATE */
|
|
png_write_gAMA_fixed(png_structp png_ptr, png_fixed_point file_gamma)
|
|
{
|
|
#ifdef PNG_USE_LOCAL_ARRAYS
|
|
PNG_gAMA;
|
|
#endif
|
|
png_byte buf[4];
|
|
|
|
png_debug(1, "in png_write_gAMA\n");
|
|
/* file_gamma is saved in 1/100,000ths */
|
|
png_save_uint_32(buf, (png_uint_32)file_gamma);
|
|
png_write_chunk(png_ptr, (png_bytep)png_gAMA, buf, (png_size_t)4);
|
|
}
|
|
#endif
|
|
#endif
|
|
|
|
#if defined(PNG_WRITE_sRGB_SUPPORTED)
|
|
/* write a sRGB chunk */
|
|
void /* PRIVATE */
|
|
png_write_sRGB(png_structp png_ptr, int srgb_intent)
|
|
{
|
|
#ifdef PNG_USE_LOCAL_ARRAYS
|
|
PNG_sRGB;
|
|
#endif
|
|
png_byte buf[1];
|
|
|
|
png_debug(1, "in png_write_sRGB\n");
|
|
if(srgb_intent >= PNG_sRGB_INTENT_LAST)
|
|
png_warning(png_ptr,
|
|
"Invalid sRGB rendering intent specified");
|
|
buf[0]=(png_byte)srgb_intent;
|
|
png_write_chunk(png_ptr, (png_bytep)png_sRGB, buf, (png_size_t)1);
|
|
}
|
|
#endif
|
|
|
|
#if defined(PNG_WRITE_iCCP_SUPPORTED)
|
|
/* write an iCCP chunk */
|
|
void /* PRIVATE */
|
|
png_write_iCCP(png_structp png_ptr, png_charp name, int compression_type,
|
|
png_charp profile, int profile_len)
|
|
{
|
|
#ifdef PNG_USE_LOCAL_ARRAYS
|
|
PNG_iCCP;
|
|
#endif
|
|
png_size_t name_len;
|
|
png_charp new_name;
|
|
compression_state comp;
|
|
|
|
png_debug(1, "in png_write_iCCP\n");
|
|
if (name == NULL || (name_len = png_check_keyword(png_ptr, name,
|
|
&new_name)) == 0)
|
|
{
|
|
png_warning(png_ptr, "Empty keyword in iCCP chunk");
|
|
return;
|
|
}
|
|
|
|
if (compression_type != PNG_COMPRESSION_TYPE_BASE)
|
|
png_warning(png_ptr, "Unknown compression type in iCCP chunk");
|
|
|
|
if (profile == NULL)
|
|
profile_len = 0;
|
|
|
|
if (profile_len)
|
|
profile_len = png_text_compress(png_ptr, profile, (png_size_t)profile_len,
|
|
PNG_COMPRESSION_TYPE_BASE, &comp);
|
|
|
|
/* make sure we include the NULL after the name and the compression type */
|
|
png_write_chunk_start(png_ptr, (png_bytep)png_iCCP,
|
|
(png_uint_32)name_len+profile_len+2);
|
|
new_name[name_len+1]=0x00;
|
|
png_write_chunk_data(png_ptr, (png_bytep)new_name, name_len + 2);
|
|
|
|
if (profile_len)
|
|
png_write_compressed_data_out(png_ptr, &comp);
|
|
|
|
png_write_chunk_end(png_ptr);
|
|
png_free(png_ptr, new_name);
|
|
}
|
|
#endif
|
|
|
|
#if defined(PNG_WRITE_sPLT_SUPPORTED)
|
|
/* write a sPLT chunk */
|
|
void /* PRIVATE */
|
|
png_write_sPLT(png_structp png_ptr, png_sPLT_tp spalette)
|
|
{
|
|
#ifdef PNG_USE_LOCAL_ARRAYS
|
|
PNG_sPLT;
|
|
#endif
|
|
png_size_t name_len;
|
|
png_charp new_name;
|
|
png_byte entrybuf[10];
|
|
int entry_size = (spalette->depth == 8 ? 6 : 10);
|
|
int palette_size = entry_size * spalette->nentries;
|
|
png_sPLT_entryp ep;
|
|
#ifdef PNG_NO_POINTER_INDEXING
|
|
int i;
|
|
#endif
|
|
|
|
png_debug(1, "in png_write_sPLT\n");
|
|
if (spalette->name == NULL || (name_len = png_check_keyword(png_ptr,
|
|
spalette->name, &new_name))==0)
|
|
{
|
|
png_warning(png_ptr, "Empty keyword in sPLT chunk");
|
|
return;
|
|
}
|
|
|
|
/* make sure we include the NULL after the name */
|
|
png_write_chunk_start(png_ptr, (png_bytep)png_sPLT,
|
|
(png_uint_32)(name_len + 2 + palette_size));
|
|
png_write_chunk_data(png_ptr, (png_bytep)new_name, name_len + 1);
|
|
png_write_chunk_data(png_ptr, (png_bytep)&spalette->depth, 1);
|
|
|
|
/* loop through each palette entry, writing appropriately */
|
|
#ifndef PNG_NO_POINTER_INDEXING
|
|
for (ep = spalette->entries; ep<spalette->entries+spalette->nentries; ep++)
|
|
{
|
|
if (spalette->depth == 8)
|
|
{
|
|
entrybuf[0] = (png_byte)ep->red;
|
|
entrybuf[1] = (png_byte)ep->green;
|
|
entrybuf[2] = (png_byte)ep->blue;
|
|
entrybuf[3] = (png_byte)ep->alpha;
|
|
png_save_uint_16(entrybuf + 4, ep->frequency);
|
|
}
|
|
else
|
|
{
|
|
png_save_uint_16(entrybuf + 0, ep->red);
|
|
png_save_uint_16(entrybuf + 2, ep->green);
|
|
png_save_uint_16(entrybuf + 4, ep->blue);
|
|
png_save_uint_16(entrybuf + 6, ep->alpha);
|
|
png_save_uint_16(entrybuf + 8, ep->frequency);
|
|
}
|
|
png_write_chunk_data(png_ptr, entrybuf, (png_size_t)entry_size);
|
|
}
|
|
#else
|
|
ep=spalette->entries;
|
|
for (i=0; i>spalette->nentries; i++)
|
|
{
|
|
if (spalette->depth == 8)
|
|
{
|
|
entrybuf[0] = (png_byte)ep[i].red;
|
|
entrybuf[1] = (png_byte)ep[i].green;
|
|
entrybuf[2] = (png_byte)ep[i].blue;
|
|
entrybuf[3] = (png_byte)ep[i].alpha;
|
|
png_save_uint_16(entrybuf + 4, ep[i].frequency);
|
|
}
|
|
else
|
|
{
|
|
png_save_uint_16(entrybuf + 0, ep[i].red);
|
|
png_save_uint_16(entrybuf + 2, ep[i].green);
|
|
png_save_uint_16(entrybuf + 4, ep[i].blue);
|
|
png_save_uint_16(entrybuf + 6, ep[i].alpha);
|
|
png_save_uint_16(entrybuf + 8, ep[i].frequency);
|
|
}
|
|
png_write_chunk_data(png_ptr, entrybuf, entry_size);
|
|
}
|
|
#endif
|
|
|
|
png_write_chunk_end(png_ptr);
|
|
png_free(png_ptr, new_name);
|
|
}
|
|
#endif
|
|
|
|
#if defined(PNG_WRITE_sBIT_SUPPORTED)
|
|
/* write the sBIT chunk */
|
|
void /* PRIVATE */
|
|
png_write_sBIT(png_structp png_ptr, png_color_8p sbit, int color_type)
|
|
{
|
|
#ifdef PNG_USE_LOCAL_ARRAYS
|
|
PNG_sBIT;
|
|
#endif
|
|
png_byte buf[4];
|
|
png_size_t size;
|
|
|
|
png_debug(1, "in png_write_sBIT\n");
|
|
/* make sure we don't depend upon the order of PNG_COLOR_8 */
|
|
if (color_type & PNG_COLOR_MASK_COLOR)
|
|
{
|
|
png_byte maxbits;
|
|
|
|
maxbits = (png_byte)(color_type==PNG_COLOR_TYPE_PALETTE ? 8 :
|
|
png_ptr->usr_bit_depth);
|
|
if (sbit->red == 0 || sbit->red > maxbits ||
|
|
sbit->green == 0 || sbit->green > maxbits ||
|
|
sbit->blue == 0 || sbit->blue > maxbits)
|
|
{
|
|
png_warning(png_ptr, "Invalid sBIT depth specified");
|
|
return;
|
|
}
|
|
buf[0] = sbit->red;
|
|
buf[1] = sbit->green;
|
|
buf[2] = sbit->blue;
|
|
size = 3;
|
|
}
|
|
else
|
|
{
|
|
if (sbit->gray == 0 || sbit->gray > png_ptr->usr_bit_depth)
|
|
{
|
|
png_warning(png_ptr, "Invalid sBIT depth specified");
|
|
return;
|
|
}
|
|
buf[0] = sbit->gray;
|
|
size = 1;
|
|
}
|
|
|
|
if (color_type & PNG_COLOR_MASK_ALPHA)
|
|
{
|
|
if (sbit->alpha == 0 || sbit->alpha > png_ptr->usr_bit_depth)
|
|
{
|
|
png_warning(png_ptr, "Invalid sBIT depth specified");
|
|
return;
|
|
}
|
|
buf[size++] = sbit->alpha;
|
|
}
|
|
|
|
png_write_chunk(png_ptr, (png_bytep)png_sBIT, buf, size);
|
|
}
|
|
#endif
|
|
|
|
#if defined(PNG_WRITE_cHRM_SUPPORTED)
|
|
/* write the cHRM chunk */
|
|
#ifdef PNG_FLOATING_POINT_SUPPORTED
|
|
void /* PRIVATE */
|
|
png_write_cHRM(png_structp png_ptr, double white_x, double white_y,
|
|
double red_x, double red_y, double green_x, double green_y,
|
|
double blue_x, double blue_y)
|
|
{
|
|
#ifdef PNG_USE_LOCAL_ARRAYS
|
|
PNG_cHRM;
|
|
#endif
|
|
png_byte buf[32];
|
|
png_uint_32 itemp;
|
|
|
|
png_debug(1, "in png_write_cHRM\n");
|
|
/* each value is saved in 1/100,000ths */
|
|
if (white_x < 0 || white_x > 0.8 || white_y < 0 || white_y > 0.8 ||
|
|
white_x + white_y > 1.0)
|
|
{
|
|
png_warning(png_ptr, "Invalid cHRM white point specified");
|
|
#if !defined(PNG_NO_CONSOLE_IO)
|
|
fprintf(stderr,"white_x=%f, white_y=%f\n",white_x, white_y);
|
|
#endif
|
|
return;
|
|
}
|
|
itemp = (png_uint_32)(white_x * 100000.0 + 0.5);
|
|
png_save_uint_32(buf, itemp);
|
|
itemp = (png_uint_32)(white_y * 100000.0 + 0.5);
|
|
png_save_uint_32(buf + 4, itemp);
|
|
|
|
if (red_x < 0 || red_x > 0.8 || red_y < 0 || red_y > 0.8 ||
|
|
red_x + red_y > 1.0)
|
|
{
|
|
png_warning(png_ptr, "Invalid cHRM red point specified");
|
|
return;
|
|
}
|
|
itemp = (png_uint_32)(red_x * 100000.0 + 0.5);
|
|
png_save_uint_32(buf + 8, itemp);
|
|
itemp = (png_uint_32)(red_y * 100000.0 + 0.5);
|
|
png_save_uint_32(buf + 12, itemp);
|
|
|
|
if (green_x < 0 || green_x > 0.8 || green_y < 0 || green_y > 0.8 ||
|
|
green_x + green_y > 1.0)
|
|
{
|
|
png_warning(png_ptr, "Invalid cHRM green point specified");
|
|
return;
|
|
}
|
|
itemp = (png_uint_32)(green_x * 100000.0 + 0.5);
|
|
png_save_uint_32(buf + 16, itemp);
|
|
itemp = (png_uint_32)(green_y * 100000.0 + 0.5);
|
|
png_save_uint_32(buf + 20, itemp);
|
|
|
|
if (blue_x < 0 || blue_x > 0.8 || blue_y < 0 || blue_y > 0.8 ||
|
|
blue_x + blue_y > 1.0)
|
|
{
|
|
png_warning(png_ptr, "Invalid cHRM blue point specified");
|
|
return;
|
|
}
|
|
itemp = (png_uint_32)(blue_x * 100000.0 + 0.5);
|
|
png_save_uint_32(buf + 24, itemp);
|
|
itemp = (png_uint_32)(blue_y * 100000.0 + 0.5);
|
|
png_save_uint_32(buf + 28, itemp);
|
|
|
|
png_write_chunk(png_ptr, (png_bytep)png_cHRM, buf, (png_size_t)32);
|
|
}
|
|
#endif
|
|
#ifdef PNG_FIXED_POINT_SUPPORTED
|
|
void /* PRIVATE */
|
|
png_write_cHRM_fixed(png_structp png_ptr, png_fixed_point white_x,
|
|
png_fixed_point white_y, png_fixed_point red_x, png_fixed_point red_y,
|
|
png_fixed_point green_x, png_fixed_point green_y, png_fixed_point blue_x,
|
|
png_fixed_point blue_y)
|
|
{
|
|
#ifdef PNG_USE_LOCAL_ARRAYS
|
|
PNG_cHRM;
|
|
#endif
|
|
png_byte buf[32];
|
|
|
|
png_debug(1, "in png_write_cHRM\n");
|
|
/* each value is saved in 1/100,000ths */
|
|
if (white_x > 80000L || white_y > 80000L || white_x + white_y > 100000L)
|
|
{
|
|
png_warning(png_ptr, "Invalid fixed cHRM white point specified");
|
|
#if !defined(PNG_NO_CONSOLE_IO)
|
|
fprintf(stderr,"white_x=%ld, white_y=%ld\n",white_x, white_y);
|
|
#endif
|
|
return;
|
|
}
|
|
png_save_uint_32(buf, (png_uint_32)white_x);
|
|
png_save_uint_32(buf + 4, (png_uint_32)white_y);
|
|
|
|
if (red_x > 80000L || red_y > 80000L || red_x + red_y > 100000L)
|
|
{
|
|
png_warning(png_ptr, "Invalid cHRM fixed red point specified");
|
|
return;
|
|
}
|
|
png_save_uint_32(buf + 8, (png_uint_32)red_x);
|
|
png_save_uint_32(buf + 12, (png_uint_32)red_y);
|
|
|
|
if (green_x > 80000L || green_y > 80000L || green_x + green_y > 100000L)
|
|
{
|
|
png_warning(png_ptr, "Invalid fixed cHRM green point specified");
|
|
return;
|
|
}
|
|
png_save_uint_32(buf + 16, (png_uint_32)green_x);
|
|
png_save_uint_32(buf + 20, (png_uint_32)green_y);
|
|
|
|
if (blue_x > 80000L || blue_y > 80000L || blue_x + blue_y > 100000L)
|
|
{
|
|
png_warning(png_ptr, "Invalid fixed cHRM blue point specified");
|
|
return;
|
|
}
|
|
png_save_uint_32(buf + 24, (png_uint_32)blue_x);
|
|
png_save_uint_32(buf + 28, (png_uint_32)blue_y);
|
|
|
|
png_write_chunk(png_ptr, (png_bytep)png_cHRM, buf, (png_size_t)32);
|
|
}
|
|
#endif
|
|
#endif
|
|
|
|
#if defined(PNG_WRITE_tRNS_SUPPORTED)
|
|
/* write the tRNS chunk */
|
|
void /* PRIVATE */
|
|
png_write_tRNS(png_structp png_ptr, png_bytep trans, png_color_16p tran,
|
|
int num_trans, int color_type)
|
|
{
|
|
#ifdef PNG_USE_LOCAL_ARRAYS
|
|
PNG_tRNS;
|
|
#endif
|
|
png_byte buf[6];
|
|
|
|
png_debug(1, "in png_write_tRNS\n");
|
|
if (color_type == PNG_COLOR_TYPE_PALETTE)
|
|
{
|
|
if (num_trans <= 0 || num_trans > (int)png_ptr->num_palette)
|
|
{
|
|
png_warning(png_ptr,"Invalid number of transparent colors specified");
|
|
return;
|
|
}
|
|
/* write the chunk out as it is */
|
|
png_write_chunk(png_ptr, (png_bytep)png_tRNS, trans, (png_size_t)num_trans);
|
|
}
|
|
else if (color_type == PNG_COLOR_TYPE_GRAY)
|
|
{
|
|
/* one 16 bit value */
|
|
if(tran->gray >= (1 << png_ptr->bit_depth))
|
|
{
|
|
png_warning(png_ptr,
|
|
"Ignoring attempt to write tRNS chunk out-of-range for bit_depth");
|
|
return;
|
|
}
|
|
png_save_uint_16(buf, tran->gray);
|
|
png_write_chunk(png_ptr, (png_bytep)png_tRNS, buf, (png_size_t)2);
|
|
}
|
|
else if (color_type == PNG_COLOR_TYPE_RGB)
|
|
{
|
|
/* three 16 bit values */
|
|
png_save_uint_16(buf, tran->red);
|
|
png_save_uint_16(buf + 2, tran->green);
|
|
png_save_uint_16(buf + 4, tran->blue);
|
|
if(png_ptr->bit_depth == 8 && (buf[0] | buf[2] | buf[4]))
|
|
{
|
|
png_warning(png_ptr,
|
|
"Ignoring attempt to write 16-bit tRNS chunk when bit_depth is 8");
|
|
return;
|
|
}
|
|
png_write_chunk(png_ptr, (png_bytep)png_tRNS, buf, (png_size_t)6);
|
|
}
|
|
else
|
|
{
|
|
png_warning(png_ptr, "Can't write tRNS with an alpha channel");
|
|
}
|
|
}
|
|
#endif
|
|
|
|
#if defined(PNG_WRITE_bKGD_SUPPORTED)
|
|
/* write the background chunk */
|
|
void /* PRIVATE */
|
|
png_write_bKGD(png_structp png_ptr, png_color_16p back, int color_type)
|
|
{
|
|
#ifdef PNG_USE_LOCAL_ARRAYS
|
|
PNG_bKGD;
|
|
#endif
|
|
png_byte buf[6];
|
|
|
|
png_debug(1, "in png_write_bKGD\n");
|
|
if (color_type == PNG_COLOR_TYPE_PALETTE)
|
|
{
|
|
if (
|
|
#if defined(PNG_MNG_FEATURES_SUPPORTED)
|
|
(png_ptr->num_palette ||
|
|
(!(png_ptr->mng_features_permitted & PNG_FLAG_MNG_EMPTY_PLTE))) &&
|
|
#endif
|
|
back->index > png_ptr->num_palette)
|
|
{
|
|
png_warning(png_ptr, "Invalid background palette index");
|
|
return;
|
|
}
|
|
buf[0] = back->index;
|
|
png_write_chunk(png_ptr, (png_bytep)png_bKGD, buf, (png_size_t)1);
|
|
}
|
|
else if (color_type & PNG_COLOR_MASK_COLOR)
|
|
{
|
|
png_save_uint_16(buf, back->red);
|
|
png_save_uint_16(buf + 2, back->green);
|
|
png_save_uint_16(buf + 4, back->blue);
|
|
if(png_ptr->bit_depth == 8 && (buf[0] | buf[2] | buf[4]))
|
|
{
|
|
png_warning(png_ptr,
|
|
"Ignoring attempt to write 16-bit bKGD chunk when bit_depth is 8");
|
|
return;
|
|
}
|
|
png_write_chunk(png_ptr, (png_bytep)png_bKGD, buf, (png_size_t)6);
|
|
}
|
|
else
|
|
{
|
|
if(back->gray >= (1 << png_ptr->bit_depth))
|
|
{
|
|
png_warning(png_ptr,
|
|
"Ignoring attempt to write bKGD chunk out-of-range for bit_depth");
|
|
return;
|
|
}
|
|
png_save_uint_16(buf, back->gray);
|
|
png_write_chunk(png_ptr, (png_bytep)png_bKGD, buf, (png_size_t)2);
|
|
}
|
|
}
|
|
#endif
|
|
|
|
#if defined(PNG_WRITE_hIST_SUPPORTED)
|
|
/* write the histogram */
|
|
void /* PRIVATE */
|
|
png_write_hIST(png_structp png_ptr, png_uint_16p hist, int num_hist)
|
|
{
|
|
#ifdef PNG_USE_LOCAL_ARRAYS
|
|
PNG_hIST;
|
|
#endif
|
|
int i;
|
|
png_byte buf[3];
|
|
|
|
png_debug(1, "in png_write_hIST\n");
|
|
if (num_hist > (int)png_ptr->num_palette)
|
|
{
|
|
png_debug2(3, "num_hist = %d, num_palette = %d\n", num_hist,
|
|
png_ptr->num_palette);
|
|
png_warning(png_ptr, "Invalid number of histogram entries specified");
|
|
return;
|
|
}
|
|
|
|
png_write_chunk_start(png_ptr, (png_bytep)png_hIST, (png_uint_32)(num_hist * 2));
|
|
for (i = 0; i < num_hist; i++)
|
|
{
|
|
png_save_uint_16(buf, hist[i]);
|
|
png_write_chunk_data(png_ptr, buf, (png_size_t)2);
|
|
}
|
|
png_write_chunk_end(png_ptr);
|
|
}
|
|
#endif
|
|
|
|
#if defined(PNG_WRITE_TEXT_SUPPORTED) || defined(PNG_WRITE_pCAL_SUPPORTED) || \
|
|
defined(PNG_WRITE_iCCP_SUPPORTED) || defined(PNG_WRITE_sPLT_SUPPORTED)
|
|
/* Check that the tEXt or zTXt keyword is valid per PNG 1.0 specification,
|
|
* and if invalid, correct the keyword rather than discarding the entire
|
|
* chunk. The PNG 1.0 specification requires keywords 1-79 characters in
|
|
* length, forbids leading or trailing whitespace, multiple internal spaces,
|
|
* and the non-break space (0x80) from ISO 8859-1. Returns keyword length.
|
|
*
|
|
* The new_key is allocated to hold the corrected keyword and must be freed
|
|
* by the calling routine. This avoids problems with trying to write to
|
|
* static keywords without having to have duplicate copies of the strings.
|
|
*/
|
|
png_size_t /* PRIVATE */
|
|
png_check_keyword(png_structp png_ptr, png_charp key, png_charpp new_key)
|
|
{
|
|
png_size_t key_len;
|
|
png_charp kp, dp;
|
|
int kflag;
|
|
int kwarn=0;
|
|
|
|
png_debug(1, "in png_check_keyword\n");
|
|
*new_key = NULL;
|
|
|
|
if (key == NULL || (key_len = png_strlen(key)) == 0)
|
|
{
|
|
png_warning(png_ptr, "zero length keyword");
|
|
return ((png_size_t)0);
|
|
}
|
|
|
|
png_debug1(2, "Keyword to be checked is '%s'\n", key);
|
|
|
|
*new_key = (png_charp)png_malloc(png_ptr, (png_uint_32)(key_len + 2));
|
|
|
|
/* Replace non-printing characters with a blank and print a warning */
|
|
for (kp = key, dp = *new_key; *kp != '\0'; kp++, dp++)
|
|
{
|
|
if (*kp < 0x20 || (*kp > 0x7E && (png_byte)*kp < 0xA1))
|
|
{
|
|
#if !defined(PNG_NO_STDIO) && !defined(_WIN32_WCE)
|
|
char msg[40];
|
|
|
|
sprintf(msg, "invalid keyword character 0x%02X", *kp);
|
|
png_warning(png_ptr, msg);
|
|
#else
|
|
png_warning(png_ptr, "invalid character in keyword");
|
|
#endif
|
|
*dp = ' ';
|
|
}
|
|
else
|
|
{
|
|
*dp = *kp;
|
|
}
|
|
}
|
|
*dp = '\0';
|
|
|
|
/* Remove any trailing white space. */
|
|
kp = *new_key + key_len - 1;
|
|
if (*kp == ' ')
|
|
{
|
|
png_warning(png_ptr, "trailing spaces removed from keyword");
|
|
|
|
while (*kp == ' ')
|
|
{
|
|
*(kp--) = '\0';
|
|
key_len--;
|
|
}
|
|
}
|
|
|
|
/* Remove any leading white space. */
|
|
kp = *new_key;
|
|
if (*kp == ' ')
|
|
{
|
|
png_warning(png_ptr, "leading spaces removed from keyword");
|
|
|
|
while (*kp == ' ')
|
|
{
|
|
kp++;
|
|
key_len--;
|
|
}
|
|
}
|
|
|
|
png_debug1(2, "Checking for multiple internal spaces in '%s'\n", kp);
|
|
|
|
/* Remove multiple internal spaces. */
|
|
for (kflag = 0, dp = *new_key; *kp != '\0'; kp++)
|
|
{
|
|
if (*kp == ' ' && kflag == 0)
|
|
{
|
|
*(dp++) = *kp;
|
|
kflag = 1;
|
|
}
|
|
else if (*kp == ' ')
|
|
{
|
|
key_len--;
|
|
kwarn=1;
|
|
}
|
|
else
|
|
{
|
|
*(dp++) = *kp;
|
|
kflag = 0;
|
|
}
|
|
}
|
|
*dp = '\0';
|
|
if(kwarn)
|
|
png_warning(png_ptr, "extra interior spaces removed from keyword");
|
|
|
|
if (key_len == 0)
|
|
{
|
|
png_free(png_ptr, *new_key);
|
|
*new_key=NULL;
|
|
png_warning(png_ptr, "Zero length keyword");
|
|
}
|
|
|
|
if (key_len > 79)
|
|
{
|
|
png_warning(png_ptr, "keyword length must be 1 - 79 characters");
|
|
new_key[79] = '\0';
|
|
key_len = 79;
|
|
}
|
|
|
|
return (key_len);
|
|
}
|
|
#endif
|
|
|
|
#if defined(PNG_WRITE_tEXt_SUPPORTED)
|
|
/* write a tEXt chunk */
|
|
void /* PRIVATE */
|
|
png_write_tEXt(png_structp png_ptr, png_charp key, png_charp text,
|
|
png_size_t text_len)
|
|
{
|
|
#ifdef PNG_USE_LOCAL_ARRAYS
|
|
PNG_tEXt;
|
|
#endif
|
|
png_size_t key_len;
|
|
png_charp new_key;
|
|
|
|
png_debug(1, "in png_write_tEXt\n");
|
|
if (key == NULL || (key_len = png_check_keyword(png_ptr, key, &new_key))==0)
|
|
{
|
|
png_warning(png_ptr, "Empty keyword in tEXt chunk");
|
|
return;
|
|
}
|
|
|
|
if (text == NULL || *text == '\0')
|
|
text_len = 0;
|
|
else
|
|
text_len = png_strlen(text);
|
|
|
|
/* make sure we include the 0 after the key */
|
|
png_write_chunk_start(png_ptr, (png_bytep)png_tEXt, (png_uint_32)key_len+text_len+1);
|
|
/*
|
|
* We leave it to the application to meet PNG-1.0 requirements on the
|
|
* contents of the text. PNG-1.0 through PNG-1.2 discourage the use of
|
|
* any non-Latin-1 characters except for NEWLINE. ISO PNG will forbid them.
|
|
* The NUL character is forbidden by PNG-1.0 through PNG-1.2 and ISO PNG.
|
|
*/
|
|
png_write_chunk_data(png_ptr, (png_bytep)new_key, key_len + 1);
|
|
if (text_len)
|
|
png_write_chunk_data(png_ptr, (png_bytep)text, text_len);
|
|
|
|
png_write_chunk_end(png_ptr);
|
|
png_free(png_ptr, new_key);
|
|
}
|
|
#endif
|
|
|
|
#if defined(PNG_WRITE_zTXt_SUPPORTED)
|
|
/* write a compressed text chunk */
|
|
void /* PRIVATE */
|
|
png_write_zTXt(png_structp png_ptr, png_charp key, png_charp text,
|
|
png_size_t text_len, int compression)
|
|
{
|
|
#ifdef PNG_USE_LOCAL_ARRAYS
|
|
PNG_zTXt;
|
|
#endif
|
|
png_size_t key_len;
|
|
char buf[1];
|
|
png_charp new_key;
|
|
compression_state comp;
|
|
|
|
png_debug(1, "in png_write_zTXt\n");
|
|
|
|
if (key == NULL || (key_len = png_check_keyword(png_ptr, key, &new_key))==0)
|
|
{
|
|
png_warning(png_ptr, "Empty keyword in zTXt chunk");
|
|
return;
|
|
}
|
|
|
|
if (text == NULL || *text == '\0' || compression==PNG_TEXT_COMPRESSION_NONE)
|
|
{
|
|
png_write_tEXt(png_ptr, new_key, text, (png_size_t)0);
|
|
png_free(png_ptr, new_key);
|
|
return;
|
|
}
|
|
|
|
text_len = png_strlen(text);
|
|
|
|
png_free(png_ptr, new_key);
|
|
|
|
/* compute the compressed data; do it now for the length */
|
|
text_len = png_text_compress(png_ptr, text, text_len, compression,
|
|
&comp);
|
|
|
|
/* write start of chunk */
|
|
png_write_chunk_start(png_ptr, (png_bytep)png_zTXt, (png_uint_32)
|
|
(key_len+text_len+2));
|
|
/* write key */
|
|
png_write_chunk_data(png_ptr, (png_bytep)key, key_len + 1);
|
|
buf[0] = (png_byte)compression;
|
|
/* write compression */
|
|
png_write_chunk_data(png_ptr, (png_bytep)buf, (png_size_t)1);
|
|
/* write the compressed data */
|
|
png_write_compressed_data_out(png_ptr, &comp);
|
|
|
|
/* close the chunk */
|
|
png_write_chunk_end(png_ptr);
|
|
}
|
|
#endif
|
|
|
|
#if defined(PNG_WRITE_iTXt_SUPPORTED)
|
|
/* write an iTXt chunk */
|
|
void /* PRIVATE */
|
|
png_write_iTXt(png_structp png_ptr, int compression, png_charp key,
|
|
png_charp lang, png_charp lang_key, png_charp text)
|
|
{
|
|
#ifdef PNG_USE_LOCAL_ARRAYS
|
|
PNG_iTXt;
|
|
#endif
|
|
png_size_t lang_len, key_len, lang_key_len, text_len;
|
|
png_charp new_lang, new_key;
|
|
png_byte cbuf[2];
|
|
compression_state comp;
|
|
|
|
png_debug(1, "in png_write_iTXt\n");
|
|
|
|
if (key == NULL || (key_len = png_check_keyword(png_ptr, key, &new_key))==0)
|
|
{
|
|
png_warning(png_ptr, "Empty keyword in iTXt chunk");
|
|
return;
|
|
}
|
|
if (lang == NULL || (lang_len = png_check_keyword(png_ptr, lang, &new_lang))==0)
|
|
{
|
|
png_warning(png_ptr, "Empty language field in iTXt chunk");
|
|
new_lang = NULL;
|
|
lang_len = 0;
|
|
}
|
|
|
|
if (lang_key == NULL)
|
|
lang_key_len = 0;
|
|
else
|
|
lang_key_len = png_strlen(lang_key);
|
|
|
|
if (text == NULL)
|
|
text_len = 0;
|
|
else
|
|
text_len = png_strlen(text);
|
|
|
|
/* compute the compressed data; do it now for the length */
|
|
text_len = png_text_compress(png_ptr, text, text_len, compression-2,
|
|
&comp);
|
|
|
|
|
|
/* make sure we include the compression flag, the compression byte,
|
|
* and the NULs after the key, lang, and lang_key parts */
|
|
|
|
png_write_chunk_start(png_ptr, (png_bytep)png_iTXt,
|
|
(png_uint_32)(
|
|
5 /* comp byte, comp flag, terminators for key, lang and lang_key */
|
|
+ key_len
|
|
+ lang_len
|
|
+ lang_key_len
|
|
+ text_len));
|
|
|
|
/*
|
|
* We leave it to the application to meet PNG-1.0 requirements on the
|
|
* contents of the text. PNG-1.0 through PNG-1.2 discourage the use of
|
|
* any non-Latin-1 characters except for NEWLINE. ISO PNG will forbid them.
|
|
* The NUL character is forbidden by PNG-1.0 through PNG-1.2 and ISO PNG.
|
|
*/
|
|
png_write_chunk_data(png_ptr, (png_bytep)new_key, key_len + 1);
|
|
|
|
/* set the compression flag */
|
|
if (compression == PNG_ITXT_COMPRESSION_NONE || \
|
|
compression == PNG_TEXT_COMPRESSION_NONE)
|
|
cbuf[0] = 0;
|
|
else /* compression == PNG_ITXT_COMPRESSION_zTXt */
|
|
cbuf[0] = 1;
|
|
/* set the compression method */
|
|
cbuf[1] = 0;
|
|
png_write_chunk_data(png_ptr, cbuf, 2);
|
|
|
|
cbuf[0] = 0;
|
|
png_write_chunk_data(png_ptr, (new_lang ? (png_bytep)new_lang : cbuf), lang_len + 1);
|
|
png_write_chunk_data(png_ptr, (lang_key ? (png_bytep)lang_key : cbuf), lang_key_len + 1);
|
|
png_write_compressed_data_out(png_ptr, &comp);
|
|
|
|
png_write_chunk_end(png_ptr);
|
|
png_free(png_ptr, new_key);
|
|
if (new_lang)
|
|
png_free(png_ptr, new_lang);
|
|
}
|
|
#endif
|
|
|
|
#if defined(PNG_WRITE_oFFs_SUPPORTED)
|
|
/* write the oFFs chunk */
|
|
void /* PRIVATE */
|
|
png_write_oFFs(png_structp png_ptr, png_int_32 x_offset, png_int_32 y_offset,
|
|
int unit_type)
|
|
{
|
|
#ifdef PNG_USE_LOCAL_ARRAYS
|
|
PNG_oFFs;
|
|
#endif
|
|
png_byte buf[9];
|
|
|
|
png_debug(1, "in png_write_oFFs\n");
|
|
if (unit_type >= PNG_OFFSET_LAST)
|
|
png_warning(png_ptr, "Unrecognized unit type for oFFs chunk");
|
|
|
|
png_save_int_32(buf, x_offset);
|
|
png_save_int_32(buf + 4, y_offset);
|
|
buf[8] = (png_byte)unit_type;
|
|
|
|
png_write_chunk(png_ptr, (png_bytep)png_oFFs, buf, (png_size_t)9);
|
|
}
|
|
#endif
|
|
|
|
#if defined(PNG_WRITE_pCAL_SUPPORTED)
|
|
/* write the pCAL chunk (described in the PNG extensions document) */
|
|
void /* PRIVATE */
|
|
png_write_pCAL(png_structp png_ptr, png_charp purpose, png_int_32 X0,
|
|
png_int_32 X1, int type, int nparams, png_charp units, png_charpp params)
|
|
{
|
|
#ifdef PNG_USE_LOCAL_ARRAYS
|
|
PNG_pCAL;
|
|
#endif
|
|
png_size_t purpose_len, units_len, total_len;
|
|
png_uint_32p params_len;
|
|
png_byte buf[10];
|
|
png_charp new_purpose;
|
|
int i;
|
|
|
|
png_debug1(1, "in png_write_pCAL (%d parameters)\n", nparams);
|
|
if (type >= PNG_EQUATION_LAST)
|
|
png_warning(png_ptr, "Unrecognized equation type for pCAL chunk");
|
|
|
|
purpose_len = png_check_keyword(png_ptr, purpose, &new_purpose) + 1;
|
|
png_debug1(3, "pCAL purpose length = %d\n", (int)purpose_len);
|
|
units_len = png_strlen(units) + (nparams == 0 ? 0 : 1);
|
|
png_debug1(3, "pCAL units length = %d\n", (int)units_len);
|
|
total_len = purpose_len + units_len + 10;
|
|
|
|
params_len = (png_uint_32p)png_malloc(png_ptr, (png_uint_32)(nparams
|
|
*sizeof(png_uint_32)));
|
|
|
|
/* Find the length of each parameter, making sure we don't count the
|
|
null terminator for the last parameter. */
|
|
for (i = 0; i < nparams; i++)
|
|
{
|
|
params_len[i] = png_strlen(params[i]) + (i == nparams - 1 ? 0 : 1);
|
|
png_debug2(3, "pCAL parameter %d length = %lu\n", i, params_len[i]);
|
|
total_len += (png_size_t)params_len[i];
|
|
}
|
|
|
|
png_debug1(3, "pCAL total length = %d\n", (int)total_len);
|
|
png_write_chunk_start(png_ptr, (png_bytep)png_pCAL, (png_uint_32)total_len);
|
|
png_write_chunk_data(png_ptr, (png_bytep)new_purpose, purpose_len);
|
|
png_save_int_32(buf, X0);
|
|
png_save_int_32(buf + 4, X1);
|
|
buf[8] = (png_byte)type;
|
|
buf[9] = (png_byte)nparams;
|
|
png_write_chunk_data(png_ptr, buf, (png_size_t)10);
|
|
png_write_chunk_data(png_ptr, (png_bytep)units, (png_size_t)units_len);
|
|
|
|
png_free(png_ptr, new_purpose);
|
|
|
|
for (i = 0; i < nparams; i++)
|
|
{
|
|
png_write_chunk_data(png_ptr, (png_bytep)params[i],
|
|
(png_size_t)params_len[i]);
|
|
}
|
|
|
|
png_free(png_ptr, params_len);
|
|
png_write_chunk_end(png_ptr);
|
|
}
|
|
#endif
|
|
|
|
#if defined(PNG_WRITE_sCAL_SUPPORTED)
|
|
/* write the sCAL chunk */
|
|
#if defined(PNG_FLOATING_POINT_SUPPORTED) && !defined(PNG_NO_STDIO)
|
|
void /* PRIVATE */
|
|
png_write_sCAL(png_structp png_ptr, int unit, double width,double height)
|
|
{
|
|
#ifdef PNG_USE_LOCAL_ARRAYS
|
|
PNG_sCAL;
|
|
#endif
|
|
png_size_t total_len;
|
|
char wbuf[32], hbuf[32];
|
|
|
|
png_debug(1, "in png_write_sCAL\n");
|
|
|
|
#if defined(_WIN32_WCE)
|
|
/* sprintf() function is not supported on WindowsCE */
|
|
{
|
|
wchar_t wc_buf[32];
|
|
swprintf(wc_buf, TEXT("%12.12e"), width);
|
|
WideCharToMultiByte(CP_ACP, 0, wc_buf, -1, wbuf, 32, NULL, NULL);
|
|
swprintf(wc_buf, TEXT("%12.12e"), height);
|
|
WideCharToMultiByte(CP_ACP, 0, wc_buf, -1, hbuf, 32, NULL, NULL);
|
|
}
|
|
#else
|
|
sprintf(wbuf, "%12.12e", width);
|
|
sprintf(hbuf, "%12.12e", height);
|
|
#endif
|
|
total_len = 1 + png_strlen(wbuf)+1 + png_strlen(hbuf);
|
|
|
|
png_debug1(3, "sCAL total length = %d\n", (int)total_len);
|
|
png_write_chunk_start(png_ptr, (png_bytep)png_sCAL, (png_uint_32)total_len);
|
|
png_write_chunk_data(png_ptr, (png_bytep)&unit, 1);
|
|
png_write_chunk_data(png_ptr, (png_bytep)wbuf, png_strlen(wbuf)+1);
|
|
png_write_chunk_data(png_ptr, (png_bytep)hbuf, png_strlen(hbuf));
|
|
|
|
png_write_chunk_end(png_ptr);
|
|
}
|
|
#else
|
|
#ifdef PNG_FIXED_POINT_SUPPORTED
|
|
void /* PRIVATE */
|
|
png_write_sCAL_s(png_structp png_ptr, int unit, png_charp width,
|
|
png_charp height)
|
|
{
|
|
#ifdef PNG_USE_LOCAL_ARRAYS
|
|
PNG_sCAL;
|
|
#endif
|
|
png_size_t total_len;
|
|
char wbuf[32], hbuf[32];
|
|
|
|
png_debug(1, "in png_write_sCAL_s\n");
|
|
|
|
png_strcpy(wbuf,(const char *)width);
|
|
png_strcpy(hbuf,(const char *)height);
|
|
total_len = 1 + png_strlen(wbuf)+1 + png_strlen(hbuf);
|
|
|
|
png_debug1(3, "sCAL total length = %d\n", total_len);
|
|
png_write_chunk_start(png_ptr, (png_bytep)png_sCAL, (png_uint_32)total_len);
|
|
png_write_chunk_data(png_ptr, (png_bytep)&unit, 1);
|
|
png_write_chunk_data(png_ptr, (png_bytep)wbuf, png_strlen(wbuf)+1);
|
|
png_write_chunk_data(png_ptr, (png_bytep)hbuf, png_strlen(hbuf));
|
|
|
|
png_write_chunk_end(png_ptr);
|
|
}
|
|
#endif
|
|
#endif
|
|
#endif
|
|
|
|
#if defined(PNG_WRITE_pHYs_SUPPORTED)
|
|
/* write the pHYs chunk */
|
|
void /* PRIVATE */
|
|
png_write_pHYs(png_structp png_ptr, png_uint_32 x_pixels_per_unit,
|
|
png_uint_32 y_pixels_per_unit,
|
|
int unit_type)
|
|
{
|
|
#ifdef PNG_USE_LOCAL_ARRAYS
|
|
PNG_pHYs;
|
|
#endif
|
|
png_byte buf[9];
|
|
|
|
png_debug(1, "in png_write_pHYs\n");
|
|
if (unit_type >= PNG_RESOLUTION_LAST)
|
|
png_warning(png_ptr, "Unrecognized unit type for pHYs chunk");
|
|
|
|
png_save_uint_32(buf, x_pixels_per_unit);
|
|
png_save_uint_32(buf + 4, y_pixels_per_unit);
|
|
buf[8] = (png_byte)unit_type;
|
|
|
|
png_write_chunk(png_ptr, (png_bytep)png_pHYs, buf, (png_size_t)9);
|
|
}
|
|
#endif
|
|
|
|
#if defined(PNG_WRITE_tIME_SUPPORTED)
|
|
/* Write the tIME chunk. Use either png_convert_from_struct_tm()
|
|
* or png_convert_from_time_t(), or fill in the structure yourself.
|
|
*/
|
|
void /* PRIVATE */
|
|
png_write_tIME(png_structp png_ptr, png_timep mod_time)
|
|
{
|
|
#ifdef PNG_USE_LOCAL_ARRAYS
|
|
PNG_tIME;
|
|
#endif
|
|
png_byte buf[7];
|
|
|
|
png_debug(1, "in png_write_tIME\n");
|
|
if (mod_time->month > 12 || mod_time->month < 1 ||
|
|
mod_time->day > 31 || mod_time->day < 1 ||
|
|
mod_time->hour > 23 || mod_time->second > 60)
|
|
{
|
|
png_warning(png_ptr, "Invalid time specified for tIME chunk");
|
|
return;
|
|
}
|
|
|
|
png_save_uint_16(buf, mod_time->year);
|
|
buf[2] = mod_time->month;
|
|
buf[3] = mod_time->day;
|
|
buf[4] = mod_time->hour;
|
|
buf[5] = mod_time->minute;
|
|
buf[6] = mod_time->second;
|
|
|
|
png_write_chunk(png_ptr, (png_bytep)png_tIME, buf, (png_size_t)7);
|
|
}
|
|
#endif
|
|
|
|
/* initializes the row writing capability of libpng */
|
|
void /* PRIVATE */
|
|
png_write_start_row(png_structp png_ptr)
|
|
{
|
|
#ifdef PNG_USE_LOCAL_ARRAYS
|
|
/* arrays to facilitate easy interlacing - use pass (0 - 6) as index */
|
|
|
|
/* start of interlace block */
|
|
int png_pass_start[7] = {0, 4, 0, 2, 0, 1, 0};
|
|
|
|
/* offset to next interlace block */
|
|
int png_pass_inc[7] = {8, 8, 4, 4, 2, 2, 1};
|
|
|
|
/* start of interlace block in the y direction */
|
|
int png_pass_ystart[7] = {0, 0, 4, 0, 2, 0, 1};
|
|
|
|
/* offset to next interlace block in the y direction */
|
|
int png_pass_yinc[7] = {8, 8, 8, 4, 4, 2, 2};
|
|
#endif
|
|
|
|
png_size_t buf_size;
|
|
|
|
png_debug(1, "in png_write_start_row\n");
|
|
buf_size = (png_size_t)(((png_ptr->width * png_ptr->usr_channels *
|
|
png_ptr->usr_bit_depth + 7) >> 3) + 1);
|
|
|
|
/* set up row buffer */
|
|
png_ptr->row_buf = (png_bytep)png_malloc(png_ptr, (png_uint_32)buf_size);
|
|
png_ptr->row_buf[0] = PNG_FILTER_VALUE_NONE;
|
|
|
|
/* set up filtering buffer, if using this filter */
|
|
if (png_ptr->do_filter & PNG_FILTER_SUB)
|
|
{
|
|
png_ptr->sub_row = (png_bytep)png_malloc(png_ptr,
|
|
(png_ptr->rowbytes + 1));
|
|
png_ptr->sub_row[0] = PNG_FILTER_VALUE_SUB;
|
|
}
|
|
|
|
/* We only need to keep the previous row if we are using one of these. */
|
|
if (png_ptr->do_filter & (PNG_FILTER_AVG | PNG_FILTER_UP | PNG_FILTER_PAETH))
|
|
{
|
|
/* set up previous row buffer */
|
|
png_ptr->prev_row = (png_bytep)png_malloc(png_ptr, (png_uint_32)buf_size);
|
|
png_memset(png_ptr->prev_row, 0, buf_size);
|
|
|
|
if (png_ptr->do_filter & PNG_FILTER_UP)
|
|
{
|
|
png_ptr->up_row = (png_bytep )png_malloc(png_ptr,
|
|
(png_ptr->rowbytes + 1));
|
|
png_ptr->up_row[0] = PNG_FILTER_VALUE_UP;
|
|
}
|
|
|
|
if (png_ptr->do_filter & PNG_FILTER_AVG)
|
|
{
|
|
png_ptr->avg_row = (png_bytep)png_malloc(png_ptr,
|
|
(png_ptr->rowbytes + 1));
|
|
png_ptr->avg_row[0] = PNG_FILTER_VALUE_AVG;
|
|
}
|
|
|
|
if (png_ptr->do_filter & PNG_FILTER_PAETH)
|
|
{
|
|
png_ptr->paeth_row = (png_bytep )png_malloc(png_ptr,
|
|
(png_ptr->rowbytes + 1));
|
|
png_ptr->paeth_row[0] = PNG_FILTER_VALUE_PAETH;
|
|
}
|
|
}
|
|
|
|
#ifdef PNG_WRITE_INTERLACING_SUPPORTED
|
|
/* if interlaced, we need to set up width and height of pass */
|
|
if (png_ptr->interlaced)
|
|
{
|
|
if (!(png_ptr->transformations & PNG_INTERLACE))
|
|
{
|
|
png_ptr->num_rows = (png_ptr->height + png_pass_yinc[0] - 1 -
|
|
png_pass_ystart[0]) / png_pass_yinc[0];
|
|
png_ptr->usr_width = (png_ptr->width + png_pass_inc[0] - 1 -
|
|
png_pass_start[0]) / png_pass_inc[0];
|
|
}
|
|
else
|
|
{
|
|
png_ptr->num_rows = png_ptr->height;
|
|
png_ptr->usr_width = png_ptr->width;
|
|
}
|
|
}
|
|
else
|
|
#endif
|
|
{
|
|
png_ptr->num_rows = png_ptr->height;
|
|
png_ptr->usr_width = png_ptr->width;
|
|
}
|
|
png_ptr->zstream.avail_out = (uInt)png_ptr->zbuf_size;
|
|
png_ptr->zstream.next_out = png_ptr->zbuf;
|
|
}
|
|
|
|
/* Internal use only. Called when finished processing a row of data. */
|
|
void /* PRIVATE */
|
|
png_write_finish_row(png_structp png_ptr)
|
|
{
|
|
#ifdef PNG_USE_LOCAL_ARRAYS
|
|
/* arrays to facilitate easy interlacing - use pass (0 - 6) as index */
|
|
|
|
/* start of interlace block */
|
|
int png_pass_start[7] = {0, 4, 0, 2, 0, 1, 0};
|
|
|
|
/* offset to next interlace block */
|
|
int png_pass_inc[7] = {8, 8, 4, 4, 2, 2, 1};
|
|
|
|
/* start of interlace block in the y direction */
|
|
int png_pass_ystart[7] = {0, 0, 4, 0, 2, 0, 1};
|
|
|
|
/* offset to next interlace block in the y direction */
|
|
int png_pass_yinc[7] = {8, 8, 8, 4, 4, 2, 2};
|
|
#endif
|
|
|
|
int ret;
|
|
|
|
png_debug(1, "in png_write_finish_row\n");
|
|
/* next row */
|
|
png_ptr->row_number++;
|
|
|
|
/* see if we are done */
|
|
if (png_ptr->row_number < png_ptr->num_rows)
|
|
return;
|
|
|
|
#ifdef PNG_WRITE_INTERLACING_SUPPORTED
|
|
/* if interlaced, go to next pass */
|
|
if (png_ptr->interlaced)
|
|
{
|
|
png_ptr->row_number = 0;
|
|
if (png_ptr->transformations & PNG_INTERLACE)
|
|
{
|
|
png_ptr->pass++;
|
|
}
|
|
else
|
|
{
|
|
/* loop until we find a non-zero width or height pass */
|
|
do
|
|
{
|
|
png_ptr->pass++;
|
|
if (png_ptr->pass >= 7)
|
|
break;
|
|
png_ptr->usr_width = (png_ptr->width +
|
|
png_pass_inc[png_ptr->pass] - 1 -
|
|
png_pass_start[png_ptr->pass]) /
|
|
png_pass_inc[png_ptr->pass];
|
|
png_ptr->num_rows = (png_ptr->height +
|
|
png_pass_yinc[png_ptr->pass] - 1 -
|
|
png_pass_ystart[png_ptr->pass]) /
|
|
png_pass_yinc[png_ptr->pass];
|
|
if (png_ptr->transformations & PNG_INTERLACE)
|
|
break;
|
|
} while (png_ptr->usr_width == 0 || png_ptr->num_rows == 0);
|
|
|
|
}
|
|
|
|
/* reset the row above the image for the next pass */
|
|
if (png_ptr->pass < 7)
|
|
{
|
|
if (png_ptr->prev_row != NULL)
|
|
png_memset(png_ptr->prev_row, 0,
|
|
(png_size_t) (((png_uint_32)png_ptr->usr_channels *
|
|
(png_uint_32)png_ptr->usr_bit_depth *
|
|
png_ptr->width + 7) >> 3) + 1);
|
|
return;
|
|
}
|
|
}
|
|
#endif
|
|
|
|
/* if we get here, we've just written the last row, so we need
|
|
to flush the compressor */
|
|
do
|
|
{
|
|
/* tell the compressor we are done */
|
|
ret = deflate(&png_ptr->zstream, Z_FINISH);
|
|
/* check for an error */
|
|
if (ret == Z_OK)
|
|
{
|
|
/* check to see if we need more room */
|
|
if (!(png_ptr->zstream.avail_out))
|
|
{
|
|
png_write_IDAT(png_ptr, png_ptr->zbuf, png_ptr->zbuf_size);
|
|
png_ptr->zstream.next_out = png_ptr->zbuf;
|
|
png_ptr->zstream.avail_out = (uInt)png_ptr->zbuf_size;
|
|
}
|
|
}
|
|
else if (ret != Z_STREAM_END)
|
|
{
|
|
if (png_ptr->zstream.msg != NULL)
|
|
png_error(png_ptr, png_ptr->zstream.msg);
|
|
else
|
|
png_error(png_ptr, "zlib error");
|
|
}
|
|
} while (ret != Z_STREAM_END);
|
|
|
|
/* write any extra space */
|
|
if (png_ptr->zstream.avail_out < png_ptr->zbuf_size)
|
|
{
|
|
png_write_IDAT(png_ptr, png_ptr->zbuf, png_ptr->zbuf_size -
|
|
png_ptr->zstream.avail_out);
|
|
}
|
|
|
|
deflateReset(&png_ptr->zstream);
|
|
}
|
|
|
|
#if defined(PNG_WRITE_INTERLACING_SUPPORTED)
|
|
/* Pick out the correct pixels for the interlace pass.
|
|
* The basic idea here is to go through the row with a source
|
|
* pointer and a destination pointer (sp and dp), and copy the
|
|
* correct pixels for the pass. As the row gets compacted,
|
|
* sp will always be >= dp, so we should never overwrite anything.
|
|
* See the default: case for the easiest code to understand.
|
|
*/
|
|
void /* PRIVATE */
|
|
png_do_write_interlace(png_row_infop row_info, png_bytep row, int pass)
|
|
{
|
|
#ifdef PNG_USE_LOCAL_ARRAYS
|
|
/* arrays to facilitate easy interlacing - use pass (0 - 6) as index */
|
|
|
|
/* start of interlace block */
|
|
int png_pass_start[7] = {0, 4, 0, 2, 0, 1, 0};
|
|
|
|
/* offset to next interlace block */
|
|
int png_pass_inc[7] = {8, 8, 4, 4, 2, 2, 1};
|
|
#endif
|
|
|
|
png_debug(1, "in png_do_write_interlace\n");
|
|
/* we don't have to do anything on the last pass (6) */
|
|
#if defined(PNG_USELESS_TESTS_SUPPORTED)
|
|
if (row != NULL && row_info != NULL && pass < 6)
|
|
#else
|
|
if (pass < 6)
|
|
#endif
|
|
{
|
|
/* each pixel depth is handled separately */
|
|
switch (row_info->pixel_depth)
|
|
{
|
|
case 1:
|
|
{
|
|
png_bytep sp;
|
|
png_bytep dp;
|
|
int shift;
|
|
int d;
|
|
int value;
|
|
png_uint_32 i;
|
|
png_uint_32 row_width = row_info->width;
|
|
|
|
dp = row;
|
|
d = 0;
|
|
shift = 7;
|
|
for (i = png_pass_start[pass]; i < row_width;
|
|
i += png_pass_inc[pass])
|
|
{
|
|
sp = row + (png_size_t)(i >> 3);
|
|
value = (int)(*sp >> (7 - (int)(i & 0x07))) & 0x01;
|
|
d |= (value << shift);
|
|
|
|
if (shift == 0)
|
|
{
|
|
shift = 7;
|
|
*dp++ = (png_byte)d;
|
|
d = 0;
|
|
}
|
|
else
|
|
shift--;
|
|
|
|
}
|
|
if (shift != 7)
|
|
*dp = (png_byte)d;
|
|
break;
|
|
}
|
|
case 2:
|
|
{
|
|
png_bytep sp;
|
|
png_bytep dp;
|
|
int shift;
|
|
int d;
|
|
int value;
|
|
png_uint_32 i;
|
|
png_uint_32 row_width = row_info->width;
|
|
|
|
dp = row;
|
|
shift = 6;
|
|
d = 0;
|
|
for (i = png_pass_start[pass]; i < row_width;
|
|
i += png_pass_inc[pass])
|
|
{
|
|
sp = row + (png_size_t)(i >> 2);
|
|
value = (*sp >> ((3 - (int)(i & 0x03)) << 1)) & 0x03;
|
|
d |= (value << shift);
|
|
|
|
if (shift == 0)
|
|
{
|
|
shift = 6;
|
|
*dp++ = (png_byte)d;
|
|
d = 0;
|
|
}
|
|
else
|
|
shift -= 2;
|
|
}
|
|
if (shift != 6)
|
|
*dp = (png_byte)d;
|
|
break;
|
|
}
|
|
case 4:
|
|
{
|
|
png_bytep sp;
|
|
png_bytep dp;
|
|
int shift;
|
|
int d;
|
|
int value;
|
|
png_uint_32 i;
|
|
png_uint_32 row_width = row_info->width;
|
|
|
|
dp = row;
|
|
shift = 4;
|
|
d = 0;
|
|
for (i = png_pass_start[pass]; i < row_width;
|
|
i += png_pass_inc[pass])
|
|
{
|
|
sp = row + (png_size_t)(i >> 1);
|
|
value = (*sp >> ((1 - (int)(i & 0x01)) << 2)) & 0x0f;
|
|
d |= (value << shift);
|
|
|
|
if (shift == 0)
|
|
{
|
|
shift = 4;
|
|
*dp++ = (png_byte)d;
|
|
d = 0;
|
|
}
|
|
else
|
|
shift -= 4;
|
|
}
|
|
if (shift != 4)
|
|
*dp = (png_byte)d;
|
|
break;
|
|
}
|
|
default:
|
|
{
|
|
png_bytep sp;
|
|
png_bytep dp;
|
|
png_uint_32 i;
|
|
png_uint_32 row_width = row_info->width;
|
|
png_size_t pixel_bytes;
|
|
|
|
/* start at the beginning */
|
|
dp = row;
|
|
/* find out how many bytes each pixel takes up */
|
|
pixel_bytes = (row_info->pixel_depth >> 3);
|
|
/* loop through the row, only looking at the pixels that
|
|
matter */
|
|
for (i = png_pass_start[pass]; i < row_width;
|
|
i += png_pass_inc[pass])
|
|
{
|
|
/* find out where the original pixel is */
|
|
sp = row + (png_size_t)i * pixel_bytes;
|
|
/* move the pixel */
|
|
if (dp != sp)
|
|
png_memcpy(dp, sp, pixel_bytes);
|
|
/* next pixel */
|
|
dp += pixel_bytes;
|
|
}
|
|
break;
|
|
}
|
|
}
|
|
/* set new row width */
|
|
row_info->width = (row_info->width +
|
|
png_pass_inc[pass] - 1 -
|
|
png_pass_start[pass]) /
|
|
png_pass_inc[pass];
|
|
row_info->rowbytes = ((row_info->width *
|
|
row_info->pixel_depth + 7) >> 3);
|
|
}
|
|
}
|
|
#endif
|
|
|
|
/* This filters the row, chooses which filter to use, if it has not already
|
|
* been specified by the application, and then writes the row out with the
|
|
* chosen filter.
|
|
*/
|
|
#define PNG_MAXSUM (~((png_uint_32)0) >> 1)
|
|
#define PNG_HISHIFT 10
|
|
#define PNG_LOMASK ((png_uint_32)0xffffL)
|
|
#define PNG_HIMASK ((png_uint_32)(~PNG_LOMASK >> PNG_HISHIFT))
|
|
void /* PRIVATE */
|
|
png_write_find_filter(png_structp png_ptr, png_row_infop row_info)
|
|
{
|
|
png_bytep prev_row, best_row, row_buf;
|
|
png_uint_32 mins, bpp;
|
|
png_byte filter_to_do = png_ptr->do_filter;
|
|
png_uint_32 row_bytes = row_info->rowbytes;
|
|
#if defined(PNG_WRITE_WEIGHTED_FILTER_SUPPORTED)
|
|
int num_p_filters = (int)png_ptr->num_prev_filters;
|
|
#endif
|
|
|
|
png_debug(1, "in png_write_find_filter\n");
|
|
/* find out how many bytes offset each pixel is */
|
|
bpp = (row_info->pixel_depth + 7) / 8;
|
|
|
|
prev_row = png_ptr->prev_row;
|
|
best_row = row_buf = png_ptr->row_buf;
|
|
mins = PNG_MAXSUM;
|
|
|
|
/* The prediction method we use is to find which method provides the
|
|
* smallest value when summing the absolute values of the distances
|
|
* from zero, using anything >= 128 as negative numbers. This is known
|
|
* as the "minimum sum of absolute differences" heuristic. Other
|
|
* heuristics are the "weighted minimum sum of absolute differences"
|
|
* (experimental and can in theory improve compression), and the "zlib
|
|
* predictive" method (not implemented yet), which does test compressions
|
|
* of lines using different filter methods, and then chooses the
|
|
* (series of) filter(s) that give minimum compressed data size (VERY
|
|
* computationally expensive).
|
|
*
|
|
* GRR 980525: consider also
|
|
* (1) minimum sum of absolute differences from running average (i.e.,
|
|
* keep running sum of non-absolute differences & count of bytes)
|
|
* [track dispersion, too? restart average if dispersion too large?]
|
|
* (1b) minimum sum of absolute differences from sliding average, probably
|
|
* with window size <= deflate window (usually 32K)
|
|
* (2) minimum sum of squared differences from zero or running average
|
|
* (i.e., ~ root-mean-square approach)
|
|
*/
|
|
|
|
|
|
/* We don't need to test the 'no filter' case if this is the only filter
|
|
* that has been chosen, as it doesn't actually do anything to the data.
|
|
*/
|
|
if ((filter_to_do & PNG_FILTER_NONE) &&
|
|
filter_to_do != PNG_FILTER_NONE)
|
|
{
|
|
png_bytep rp;
|
|
png_uint_32 sum = 0;
|
|
png_uint_32 i;
|
|
int v;
|
|
|
|
for (i = 0, rp = row_buf + 1; i < row_bytes; i++, rp++)
|
|
{
|
|
v = *rp;
|
|
sum += (v < 128) ? v : 256 - v;
|
|
}
|
|
|
|
#if defined(PNG_WRITE_WEIGHTED_FILTER_SUPPORTED)
|
|
if (png_ptr->heuristic_method == PNG_FILTER_HEURISTIC_WEIGHTED)
|
|
{
|
|
png_uint_32 sumhi, sumlo;
|
|
int j;
|
|
sumlo = sum & PNG_LOMASK;
|
|
sumhi = (sum >> PNG_HISHIFT) & PNG_HIMASK; /* Gives us some footroom */
|
|
|
|
/* Reduce the sum if we match any of the previous rows */
|
|
for (j = 0; j < num_p_filters; j++)
|
|
{
|
|
if (png_ptr->prev_filters[j] == PNG_FILTER_VALUE_NONE)
|
|
{
|
|
sumlo = (sumlo * png_ptr->filter_weights[j]) >>
|
|
PNG_WEIGHT_SHIFT;
|
|
sumhi = (sumhi * png_ptr->filter_weights[j]) >>
|
|
PNG_WEIGHT_SHIFT;
|
|
}
|
|
}
|
|
|
|
/* Factor in the cost of this filter (this is here for completeness,
|
|
* but it makes no sense to have a "cost" for the NONE filter, as
|
|
* it has the minimum possible computational cost - none).
|
|
*/
|
|
sumlo = (sumlo * png_ptr->filter_costs[PNG_FILTER_VALUE_NONE]) >>
|
|
PNG_COST_SHIFT;
|
|
sumhi = (sumhi * png_ptr->filter_costs[PNG_FILTER_VALUE_NONE]) >>
|
|
PNG_COST_SHIFT;
|
|
|
|
if (sumhi > PNG_HIMASK)
|
|
sum = PNG_MAXSUM;
|
|
else
|
|
sum = (sumhi << PNG_HISHIFT) + sumlo;
|
|
}
|
|
#endif
|
|
mins = sum;
|
|
}
|
|
|
|
/* sub filter */
|
|
if (filter_to_do == PNG_FILTER_SUB)
|
|
/* it's the only filter so no testing is needed */
|
|
{
|
|
png_bytep rp, lp, dp;
|
|
png_uint_32 i;
|
|
for (i = 0, rp = row_buf + 1, dp = png_ptr->sub_row + 1; i < bpp;
|
|
i++, rp++, dp++)
|
|
{
|
|
*dp = *rp;
|
|
}
|
|
for (lp = row_buf + 1; i < row_bytes;
|
|
i++, rp++, lp++, dp++)
|
|
{
|
|
*dp = (png_byte)(((int)*rp - (int)*lp) & 0xff);
|
|
}
|
|
best_row = png_ptr->sub_row;
|
|
}
|
|
|
|
else if (filter_to_do & PNG_FILTER_SUB)
|
|
{
|
|
png_bytep rp, dp, lp;
|
|
png_uint_32 sum = 0, lmins = mins;
|
|
png_uint_32 i;
|
|
int v;
|
|
|
|
#if defined(PNG_WRITE_WEIGHTED_FILTER_SUPPORTED)
|
|
/* We temporarily increase the "minimum sum" by the factor we
|
|
* would reduce the sum of this filter, so that we can do the
|
|
* early exit comparison without scaling the sum each time.
|
|
*/
|
|
if (png_ptr->heuristic_method == PNG_FILTER_HEURISTIC_WEIGHTED)
|
|
{
|
|
int j;
|
|
png_uint_32 lmhi, lmlo;
|
|
lmlo = lmins & PNG_LOMASK;
|
|
lmhi = (lmins >> PNG_HISHIFT) & PNG_HIMASK;
|
|
|
|
for (j = 0; j < num_p_filters; j++)
|
|
{
|
|
if (png_ptr->prev_filters[j] == PNG_FILTER_VALUE_SUB)
|
|
{
|
|
lmlo = (lmlo * png_ptr->inv_filter_weights[j]) >>
|
|
PNG_WEIGHT_SHIFT;
|
|
lmhi = (lmhi * png_ptr->inv_filter_weights[j]) >>
|
|
PNG_WEIGHT_SHIFT;
|
|
}
|
|
}
|
|
|
|
lmlo = (lmlo * png_ptr->inv_filter_costs[PNG_FILTER_VALUE_SUB]) >>
|
|
PNG_COST_SHIFT;
|
|
lmhi = (lmhi * png_ptr->inv_filter_costs[PNG_FILTER_VALUE_SUB]) >>
|
|
PNG_COST_SHIFT;
|
|
|
|
if (lmhi > PNG_HIMASK)
|
|
lmins = PNG_MAXSUM;
|
|
else
|
|
lmins = (lmhi << PNG_HISHIFT) + lmlo;
|
|
}
|
|
#endif
|
|
|
|
for (i = 0, rp = row_buf + 1, dp = png_ptr->sub_row + 1; i < bpp;
|
|
i++, rp++, dp++)
|
|
{
|
|
v = *dp = *rp;
|
|
|
|
sum += (v < 128) ? v : 256 - v;
|
|
}
|
|
for (lp = row_buf + 1; i < row_info->rowbytes;
|
|
i++, rp++, lp++, dp++)
|
|
{
|
|
v = *dp = (png_byte)(((int)*rp - (int)*lp) & 0xff);
|
|
|
|
sum += (v < 128) ? v : 256 - v;
|
|
|
|
if (sum > lmins) /* We are already worse, don't continue. */
|
|
break;
|
|
}
|
|
|
|
#if defined(PNG_WRITE_WEIGHTED_FILTER_SUPPORTED)
|
|
if (png_ptr->heuristic_method == PNG_FILTER_HEURISTIC_WEIGHTED)
|
|
{
|
|
int j;
|
|
png_uint_32 sumhi, sumlo;
|
|
sumlo = sum & PNG_LOMASK;
|
|
sumhi = (sum >> PNG_HISHIFT) & PNG_HIMASK;
|
|
|
|
for (j = 0; j < num_p_filters; j++)
|
|
{
|
|
if (png_ptr->prev_filters[j] == PNG_FILTER_VALUE_SUB)
|
|
{
|
|
sumlo = (sumlo * png_ptr->inv_filter_weights[j]) >>
|
|
PNG_WEIGHT_SHIFT;
|
|
sumhi = (sumhi * png_ptr->inv_filter_weights[j]) >>
|
|
PNG_WEIGHT_SHIFT;
|
|
}
|
|
}
|
|
|
|
sumlo = (sumlo * png_ptr->inv_filter_costs[PNG_FILTER_VALUE_SUB]) >>
|
|
PNG_COST_SHIFT;
|
|
sumhi = (sumhi * png_ptr->inv_filter_costs[PNG_FILTER_VALUE_SUB]) >>
|
|
PNG_COST_SHIFT;
|
|
|
|
if (sumhi > PNG_HIMASK)
|
|
sum = PNG_MAXSUM;
|
|
else
|
|
sum = (sumhi << PNG_HISHIFT) + sumlo;
|
|
}
|
|
#endif
|
|
|
|
if (sum < mins)
|
|
{
|
|
mins = sum;
|
|
best_row = png_ptr->sub_row;
|
|
}
|
|
}
|
|
|
|
/* up filter */
|
|
if (filter_to_do == PNG_FILTER_UP)
|
|
{
|
|
png_bytep rp, dp, pp;
|
|
png_uint_32 i;
|
|
|
|
for (i = 0, rp = row_buf + 1, dp = png_ptr->up_row + 1,
|
|
pp = prev_row + 1; i < row_bytes;
|
|
i++, rp++, pp++, dp++)
|
|
{
|
|
*dp = (png_byte)(((int)*rp - (int)*pp) & 0xff);
|
|
}
|
|
best_row = png_ptr->up_row;
|
|
}
|
|
|
|
else if (filter_to_do & PNG_FILTER_UP)
|
|
{
|
|
png_bytep rp, dp, pp;
|
|
png_uint_32 sum = 0, lmins = mins;
|
|
png_uint_32 i;
|
|
int v;
|
|
|
|
|
|
#if defined(PNG_WRITE_WEIGHTED_FILTER_SUPPORTED)
|
|
if (png_ptr->heuristic_method == PNG_FILTER_HEURISTIC_WEIGHTED)
|
|
{
|
|
int j;
|
|
png_uint_32 lmhi, lmlo;
|
|
lmlo = lmins & PNG_LOMASK;
|
|
lmhi = (lmins >> PNG_HISHIFT) & PNG_HIMASK;
|
|
|
|
for (j = 0; j < num_p_filters; j++)
|
|
{
|
|
if (png_ptr->prev_filters[j] == PNG_FILTER_VALUE_UP)
|
|
{
|
|
lmlo = (lmlo * png_ptr->inv_filter_weights[j]) >>
|
|
PNG_WEIGHT_SHIFT;
|
|
lmhi = (lmhi * png_ptr->inv_filter_weights[j]) >>
|
|
PNG_WEIGHT_SHIFT;
|
|
}
|
|
}
|
|
|
|
lmlo = (lmlo * png_ptr->inv_filter_costs[PNG_FILTER_VALUE_UP]) >>
|
|
PNG_COST_SHIFT;
|
|
lmhi = (lmhi * png_ptr->inv_filter_costs[PNG_FILTER_VALUE_UP]) >>
|
|
PNG_COST_SHIFT;
|
|
|
|
if (lmhi > PNG_HIMASK)
|
|
lmins = PNG_MAXSUM;
|
|
else
|
|
lmins = (lmhi << PNG_HISHIFT) + lmlo;
|
|
}
|
|
#endif
|
|
|
|
for (i = 0, rp = row_buf + 1, dp = png_ptr->up_row + 1,
|
|
pp = prev_row + 1; i < row_bytes; i++)
|
|
{
|
|
v = *dp++ = (png_byte)(((int)*rp++ - (int)*pp++) & 0xff);
|
|
|
|
sum += (v < 128) ? v : 256 - v;
|
|
|
|
if (sum > lmins) /* We are already worse, don't continue. */
|
|
break;
|
|
}
|
|
|
|
#if defined(PNG_WRITE_WEIGHTED_FILTER_SUPPORTED)
|
|
if (png_ptr->heuristic_method == PNG_FILTER_HEURISTIC_WEIGHTED)
|
|
{
|
|
int j;
|
|
png_uint_32 sumhi, sumlo;
|
|
sumlo = sum & PNG_LOMASK;
|
|
sumhi = (sum >> PNG_HISHIFT) & PNG_HIMASK;
|
|
|
|
for (j = 0; j < num_p_filters; j++)
|
|
{
|
|
if (png_ptr->prev_filters[j] == PNG_FILTER_VALUE_UP)
|
|
{
|
|
sumlo = (sumlo * png_ptr->filter_weights[j]) >>
|
|
PNG_WEIGHT_SHIFT;
|
|
sumhi = (sumhi * png_ptr->filter_weights[j]) >>
|
|
PNG_WEIGHT_SHIFT;
|
|
}
|
|
}
|
|
|
|
sumlo = (sumlo * png_ptr->filter_costs[PNG_FILTER_VALUE_UP]) >>
|
|
PNG_COST_SHIFT;
|
|
sumhi = (sumhi * png_ptr->filter_costs[PNG_FILTER_VALUE_UP]) >>
|
|
PNG_COST_SHIFT;
|
|
|
|
if (sumhi > PNG_HIMASK)
|
|
sum = PNG_MAXSUM;
|
|
else
|
|
sum = (sumhi << PNG_HISHIFT) + sumlo;
|
|
}
|
|
#endif
|
|
|
|
if (sum < mins)
|
|
{
|
|
mins = sum;
|
|
best_row = png_ptr->up_row;
|
|
}
|
|
}
|
|
|
|
/* avg filter */
|
|
if (filter_to_do == PNG_FILTER_AVG)
|
|
{
|
|
png_bytep rp, dp, pp, lp;
|
|
png_uint_32 i;
|
|
for (i = 0, rp = row_buf + 1, dp = png_ptr->avg_row + 1,
|
|
pp = prev_row + 1; i < bpp; i++)
|
|
{
|
|
*dp++ = (png_byte)(((int)*rp++ - ((int)*pp++ / 2)) & 0xff);
|
|
}
|
|
for (lp = row_buf + 1; i < row_bytes; i++)
|
|
{
|
|
*dp++ = (png_byte)(((int)*rp++ - (((int)*pp++ + (int)*lp++) / 2))
|
|
& 0xff);
|
|
}
|
|
best_row = png_ptr->avg_row;
|
|
}
|
|
|
|
else if (filter_to_do & PNG_FILTER_AVG)
|
|
{
|
|
png_bytep rp, dp, pp, lp;
|
|
png_uint_32 sum = 0, lmins = mins;
|
|
png_uint_32 i;
|
|
int v;
|
|
|
|
#if defined(PNG_WRITE_WEIGHTED_FILTER_SUPPORTED)
|
|
if (png_ptr->heuristic_method == PNG_FILTER_HEURISTIC_WEIGHTED)
|
|
{
|
|
int j;
|
|
png_uint_32 lmhi, lmlo;
|
|
lmlo = lmins & PNG_LOMASK;
|
|
lmhi = (lmins >> PNG_HISHIFT) & PNG_HIMASK;
|
|
|
|
for (j = 0; j < num_p_filters; j++)
|
|
{
|
|
if (png_ptr->prev_filters[j] == PNG_FILTER_VALUE_AVG)
|
|
{
|
|
lmlo = (lmlo * png_ptr->inv_filter_weights[j]) >>
|
|
PNG_WEIGHT_SHIFT;
|
|
lmhi = (lmhi * png_ptr->inv_filter_weights[j]) >>
|
|
PNG_WEIGHT_SHIFT;
|
|
}
|
|
}
|
|
|
|
lmlo = (lmlo * png_ptr->inv_filter_costs[PNG_FILTER_VALUE_AVG]) >>
|
|
PNG_COST_SHIFT;
|
|
lmhi = (lmhi * png_ptr->inv_filter_costs[PNG_FILTER_VALUE_AVG]) >>
|
|
PNG_COST_SHIFT;
|
|
|
|
if (lmhi > PNG_HIMASK)
|
|
lmins = PNG_MAXSUM;
|
|
else
|
|
lmins = (lmhi << PNG_HISHIFT) + lmlo;
|
|
}
|
|
#endif
|
|
|
|
for (i = 0, rp = row_buf + 1, dp = png_ptr->avg_row + 1,
|
|
pp = prev_row + 1; i < bpp; i++)
|
|
{
|
|
v = *dp++ = (png_byte)(((int)*rp++ - ((int)*pp++ / 2)) & 0xff);
|
|
|
|
sum += (v < 128) ? v : 256 - v;
|
|
}
|
|
for (lp = row_buf + 1; i < row_bytes; i++)
|
|
{
|
|
v = *dp++ =
|
|
(png_byte)(((int)*rp++ - (((int)*pp++ + (int)*lp++) / 2)) & 0xff);
|
|
|
|
sum += (v < 128) ? v : 256 - v;
|
|
|
|
if (sum > lmins) /* We are already worse, don't continue. */
|
|
break;
|
|
}
|
|
|
|
#if defined(PNG_WRITE_WEIGHTED_FILTER_SUPPORTED)
|
|
if (png_ptr->heuristic_method == PNG_FILTER_HEURISTIC_WEIGHTED)
|
|
{
|
|
int j;
|
|
png_uint_32 sumhi, sumlo;
|
|
sumlo = sum & PNG_LOMASK;
|
|
sumhi = (sum >> PNG_HISHIFT) & PNG_HIMASK;
|
|
|
|
for (j = 0; j < num_p_filters; j++)
|
|
{
|
|
if (png_ptr->prev_filters[j] == PNG_FILTER_VALUE_NONE)
|
|
{
|
|
sumlo = (sumlo * png_ptr->filter_weights[j]) >>
|
|
PNG_WEIGHT_SHIFT;
|
|
sumhi = (sumhi * png_ptr->filter_weights[j]) >>
|
|
PNG_WEIGHT_SHIFT;
|
|
}
|
|
}
|
|
|
|
sumlo = (sumlo * png_ptr->filter_costs[PNG_FILTER_VALUE_AVG]) >>
|
|
PNG_COST_SHIFT;
|
|
sumhi = (sumhi * png_ptr->filter_costs[PNG_FILTER_VALUE_AVG]) >>
|
|
PNG_COST_SHIFT;
|
|
|
|
if (sumhi > PNG_HIMASK)
|
|
sum = PNG_MAXSUM;
|
|
else
|
|
sum = (sumhi << PNG_HISHIFT) + sumlo;
|
|
}
|
|
#endif
|
|
|
|
if (sum < mins)
|
|
{
|
|
mins = sum;
|
|
best_row = png_ptr->avg_row;
|
|
}
|
|
}
|
|
|
|
/* Paeth filter */
|
|
if (filter_to_do == PNG_FILTER_PAETH)
|
|
{
|
|
png_bytep rp, dp, pp, cp, lp;
|
|
png_uint_32 i;
|
|
for (i = 0, rp = row_buf + 1, dp = png_ptr->paeth_row + 1,
|
|
pp = prev_row + 1; i < bpp; i++)
|
|
{
|
|
*dp++ = (png_byte)(((int)*rp++ - (int)*pp++) & 0xff);
|
|
}
|
|
|
|
for (lp = row_buf + 1, cp = prev_row + 1; i < row_bytes; i++)
|
|
{
|
|
int a, b, c, pa, pb, pc, p;
|
|
|
|
b = *pp++;
|
|
c = *cp++;
|
|
a = *lp++;
|
|
|
|
p = b - c;
|
|
pc = a - c;
|
|
|
|
#ifdef PNG_USE_ABS
|
|
pa = abs(p);
|
|
pb = abs(pc);
|
|
pc = abs(p + pc);
|
|
#else
|
|
pa = p < 0 ? -p : p;
|
|
pb = pc < 0 ? -pc : pc;
|
|
pc = (p + pc) < 0 ? -(p + pc) : p + pc;
|
|
#endif
|
|
|
|
p = (pa <= pb && pa <=pc) ? a : (pb <= pc) ? b : c;
|
|
|
|
*dp++ = (png_byte)(((int)*rp++ - p) & 0xff);
|
|
}
|
|
best_row = png_ptr->paeth_row;
|
|
}
|
|
|
|
else if (filter_to_do & PNG_FILTER_PAETH)
|
|
{
|
|
png_bytep rp, dp, pp, cp, lp;
|
|
png_uint_32 sum = 0, lmins = mins;
|
|
png_uint_32 i;
|
|
int v;
|
|
|
|
#if defined(PNG_WRITE_WEIGHTED_FILTER_SUPPORTED)
|
|
if (png_ptr->heuristic_method == PNG_FILTER_HEURISTIC_WEIGHTED)
|
|
{
|
|
int j;
|
|
png_uint_32 lmhi, lmlo;
|
|
lmlo = lmins & PNG_LOMASK;
|
|
lmhi = (lmins >> PNG_HISHIFT) & PNG_HIMASK;
|
|
|
|
for (j = 0; j < num_p_filters; j++)
|
|
{
|
|
if (png_ptr->prev_filters[j] == PNG_FILTER_VALUE_PAETH)
|
|
{
|
|
lmlo = (lmlo * png_ptr->inv_filter_weights[j]) >>
|
|
PNG_WEIGHT_SHIFT;
|
|
lmhi = (lmhi * png_ptr->inv_filter_weights[j]) >>
|
|
PNG_WEIGHT_SHIFT;
|
|
}
|
|
}
|
|
|
|
lmlo = (lmlo * png_ptr->inv_filter_costs[PNG_FILTER_VALUE_PAETH]) >>
|
|
PNG_COST_SHIFT;
|
|
lmhi = (lmhi * png_ptr->inv_filter_costs[PNG_FILTER_VALUE_PAETH]) >>
|
|
PNG_COST_SHIFT;
|
|
|
|
if (lmhi > PNG_HIMASK)
|
|
lmins = PNG_MAXSUM;
|
|
else
|
|
lmins = (lmhi << PNG_HISHIFT) + lmlo;
|
|
}
|
|
#endif
|
|
|
|
for (i = 0, rp = row_buf + 1, dp = png_ptr->paeth_row + 1,
|
|
pp = prev_row + 1; i < bpp; i++)
|
|
{
|
|
v = *dp++ = (png_byte)(((int)*rp++ - (int)*pp++) & 0xff);
|
|
|
|
sum += (v < 128) ? v : 256 - v;
|
|
}
|
|
|
|
for (lp = row_buf + 1, cp = prev_row + 1; i < row_bytes; i++)
|
|
{
|
|
int a, b, c, pa, pb, pc, p;
|
|
|
|
b = *pp++;
|
|
c = *cp++;
|
|
a = *lp++;
|
|
|
|
#ifndef PNG_SLOW_PAETH
|
|
p = b - c;
|
|
pc = a - c;
|
|
#ifdef PNG_USE_ABS
|
|
pa = abs(p);
|
|
pb = abs(pc);
|
|
pc = abs(p + pc);
|
|
#else
|
|
pa = p < 0 ? -p : p;
|
|
pb = pc < 0 ? -pc : pc;
|
|
pc = (p + pc) < 0 ? -(p + pc) : p + pc;
|
|
#endif
|
|
p = (pa <= pb && pa <=pc) ? a : (pb <= pc) ? b : c;
|
|
#else /* PNG_SLOW_PAETH */
|
|
p = a + b - c;
|
|
pa = abs(p - a);
|
|
pb = abs(p - b);
|
|
pc = abs(p - c);
|
|
if (pa <= pb && pa <= pc)
|
|
p = a;
|
|
else if (pb <= pc)
|
|
p = b;
|
|
else
|
|
p = c;
|
|
#endif /* PNG_SLOW_PAETH */
|
|
|
|
v = *dp++ = (png_byte)(((int)*rp++ - p) & 0xff);
|
|
|
|
sum += (v < 128) ? v : 256 - v;
|
|
|
|
if (sum > lmins) /* We are already worse, don't continue. */
|
|
break;
|
|
}
|
|
|
|
#if defined(PNG_WRITE_WEIGHTED_FILTER_SUPPORTED)
|
|
if (png_ptr->heuristic_method == PNG_FILTER_HEURISTIC_WEIGHTED)
|
|
{
|
|
int j;
|
|
png_uint_32 sumhi, sumlo;
|
|
sumlo = sum & PNG_LOMASK;
|
|
sumhi = (sum >> PNG_HISHIFT) & PNG_HIMASK;
|
|
|
|
for (j = 0; j < num_p_filters; j++)
|
|
{
|
|
if (png_ptr->prev_filters[j] == PNG_FILTER_VALUE_PAETH)
|
|
{
|
|
sumlo = (sumlo * png_ptr->filter_weights[j]) >>
|
|
PNG_WEIGHT_SHIFT;
|
|
sumhi = (sumhi * png_ptr->filter_weights[j]) >>
|
|
PNG_WEIGHT_SHIFT;
|
|
}
|
|
}
|
|
|
|
sumlo = (sumlo * png_ptr->filter_costs[PNG_FILTER_VALUE_PAETH]) >>
|
|
PNG_COST_SHIFT;
|
|
sumhi = (sumhi * png_ptr->filter_costs[PNG_FILTER_VALUE_PAETH]) >>
|
|
PNG_COST_SHIFT;
|
|
|
|
if (sumhi > PNG_HIMASK)
|
|
sum = PNG_MAXSUM;
|
|
else
|
|
sum = (sumhi << PNG_HISHIFT) + sumlo;
|
|
}
|
|
#endif
|
|
|
|
if (sum < mins)
|
|
{
|
|
best_row = png_ptr->paeth_row;
|
|
}
|
|
}
|
|
|
|
/* Do the actual writing of the filtered row data from the chosen filter. */
|
|
|
|
png_write_filtered_row(png_ptr, best_row);
|
|
|
|
#if defined(PNG_WRITE_WEIGHTED_FILTER_SUPPORTED)
|
|
/* Save the type of filter we picked this time for future calculations */
|
|
if (png_ptr->num_prev_filters > 0)
|
|
{
|
|
int j;
|
|
for (j = 1; j < num_p_filters; j++)
|
|
{
|
|
png_ptr->prev_filters[j] = png_ptr->prev_filters[j - 1];
|
|
}
|
|
png_ptr->prev_filters[j] = best_row[0];
|
|
}
|
|
#endif
|
|
}
|
|
|
|
|
|
/* Do the actual writing of a previously filtered row. */
|
|
void /* PRIVATE */
|
|
png_write_filtered_row(png_structp png_ptr, png_bytep filtered_row)
|
|
{
|
|
png_debug(1, "in png_write_filtered_row\n");
|
|
png_debug1(2, "filter = %d\n", filtered_row[0]);
|
|
/* set up the zlib input buffer */
|
|
|
|
png_ptr->zstream.next_in = filtered_row;
|
|
png_ptr->zstream.avail_in = (uInt)png_ptr->row_info.rowbytes + 1;
|
|
/* repeat until we have compressed all the data */
|
|
do
|
|
{
|
|
int ret; /* return of zlib */
|
|
|
|
/* compress the data */
|
|
ret = deflate(&png_ptr->zstream, Z_NO_FLUSH);
|
|
/* check for compression errors */
|
|
if (ret != Z_OK)
|
|
{
|
|
if (png_ptr->zstream.msg != NULL)
|
|
png_error(png_ptr, png_ptr->zstream.msg);
|
|
else
|
|
png_error(png_ptr, "zlib error");
|
|
}
|
|
|
|
/* see if it is time to write another IDAT */
|
|
if (!(png_ptr->zstream.avail_out))
|
|
{
|
|
/* write the IDAT and reset the zlib output buffer */
|
|
png_write_IDAT(png_ptr, png_ptr->zbuf, png_ptr->zbuf_size);
|
|
png_ptr->zstream.next_out = png_ptr->zbuf;
|
|
png_ptr->zstream.avail_out = (uInt)png_ptr->zbuf_size;
|
|
}
|
|
/* repeat until all data has been compressed */
|
|
} while (png_ptr->zstream.avail_in);
|
|
|
|
/* swap the current and previous rows */
|
|
if (png_ptr->prev_row != NULL)
|
|
{
|
|
png_bytep tptr;
|
|
|
|
tptr = png_ptr->prev_row;
|
|
png_ptr->prev_row = png_ptr->row_buf;
|
|
png_ptr->row_buf = tptr;
|
|
}
|
|
|
|
/* finish row - updates counters and flushes zlib if last row */
|
|
png_write_finish_row(png_ptr);
|
|
|
|
#if defined(PNG_WRITE_FLUSH_SUPPORTED)
|
|
png_ptr->flush_rows++;
|
|
|
|
if (png_ptr->flush_dist > 0 &&
|
|
png_ptr->flush_rows >= png_ptr->flush_dist)
|
|
{
|
|
png_write_flush(png_ptr);
|
|
}
|
|
#endif
|
|
}
|
|
#endif /* PNG_WRITE_SUPPORTED */
|