/* * jpegint.h * * Copyright (C) 1991-1994, Thomas G. Lane. * This file is part of the Independent JPEG Group's software. * For conditions of distribution and use, see the accompanying README file. * * This file provides common declarations for the various JPEG modules. * These declarations are considered internal to the JPEG library; most * applications using the library shouldn't need to include this file. */ /* Declarations for both compression & decompression */ typedef enum { /* Operating modes for buffer controllers */ JBUF_PASS_THRU, /* Plain stripwise operation */ JBUF_CRANK_SOURCE, /* Run source subobject only, no output */ /* Remaining modes require a full-image buffer to have been created */ JBUF_SAVE_SOURCE, /* Run source subobject only, save output */ JBUF_CRANK_DEST, /* Run dest subobject only, using saved data */ JBUF_SAVE_AND_PASS /* Run both subobjects, save output */ } J_BUF_MODE; /* Values of global_state field */ #define CSTATE_START 100 /* after create_compress */ #define CSTATE_SCANNING 101 /* start_compress done, write_scanlines OK */ #define DSTATE_START 200 /* after create_decompress */ #define DSTATE_INHEADER 201 /* read_header initialized but not done */ #define DSTATE_READY 202 /* read_header done, found image */ #define DSTATE_SCANNING 203 /* start_decompress done, read_scanlines OK */ #define DSTATE_STOPPING 204 /* done reading data, looking for EOI */ /* Declarations for compression modules */ /* Master control module */ struct jpeg_comp_master { JMETHOD(void, prepare_for_pass, (j_compress_ptr cinfo)); JMETHOD(void, pass_startup, (j_compress_ptr cinfo)); JMETHOD(void, finish_pass, (j_compress_ptr cinfo)); /* State variables made visible to other modules */ boolean call_pass_startup; /* True if pass_startup must be called */ boolean is_last_pass; /* True during last pass */ }; /* Main buffer control (downsampled-data buffer) */ struct jpeg_c_main_controller { JMETHOD(void, start_pass, (j_compress_ptr cinfo, J_BUF_MODE pass_mode)); JMETHOD(void, process_data, (j_compress_ptr cinfo, JSAMPARRAY input_buf, JDIMENSION *in_row_ctr, JDIMENSION in_rows_avail)); }; /* Compression preprocessing (downsampling input buffer control) */ struct jpeg_c_prep_controller { JMETHOD(void, start_pass, (j_compress_ptr cinfo, J_BUF_MODE pass_mode)); JMETHOD(void, pre_process_data, (j_compress_ptr cinfo, JSAMPARRAY input_buf, JDIMENSION *in_row_ctr, JDIMENSION in_rows_avail, JSAMPIMAGE output_buf, JDIMENSION *out_row_group_ctr, JDIMENSION out_row_groups_avail)); }; /* Coefficient buffer control */ struct jpeg_c_coef_controller { JMETHOD(void, start_pass, (j_compress_ptr cinfo, J_BUF_MODE pass_mode)); JMETHOD(void, compress_data, (j_compress_ptr cinfo, JSAMPIMAGE input_buf, JDIMENSION *in_mcu_ctr)); }; /* Colorspace conversion */ struct jpeg_color_converter { JMETHOD(void, start_pass, (j_compress_ptr cinfo)); JMETHOD(void, color_convert, (j_compress_ptr cinfo, JSAMPARRAY input_buf, JSAMPIMAGE output_buf, JDIMENSION output_row, int num_rows)); }; /* Downsampling */ struct jpeg_downsampler { JMETHOD(void, start_pass, (j_compress_ptr cinfo)); JMETHOD(void, downsample, (j_compress_ptr cinfo, JSAMPIMAGE input_buf, JSAMPIMAGE output_buf, JDIMENSION out_row_group_index)); boolean need_context_rows; /* TRUE if need rows above & below */ }; /* Forward DCT (also controls coefficient quantization) */ struct jpeg_forward_dct { JMETHOD(void, start_pass, (j_compress_ptr cinfo)); /* perhaps this should be an array??? */ JMETHOD(void, forward_DCT, (j_compress_ptr cinfo, jpeg_component_info * compptr, JSAMPARRAY sample_data, JBLOCKROW coef_blocks, JDIMENSION start_row, JDIMENSION start_col, JDIMENSION num_blocks)); }; /* JCQUANT_TBL details made visible for jpeg_alloc_quant_table */ typedef struct { JQUANT_TBL pub; /* public fields */ /* Extra data for encoding */ /* The actual pre-DCT divisors -- may differ from quantizer values */ /* found in the DQT marker, if an unnormalized DCT is used. */ /* Given in zigzag order. */ MULTIPLIER divisors[DCTSIZE2]; } JCQUANT_TBL; /* Entropy encoding */ struct jpeg_entropy_encoder { JMETHOD(void, start_pass, (j_compress_ptr cinfo, boolean gather_statistics)); JMETHOD(boolean, encode_mcu, (j_compress_ptr cinfo, JBLOCKROW *MCU_data)); JMETHOD(void, finish_pass, (j_compress_ptr cinfo)); }; /* JCHUFF_TBL details made visible for jpeg_alloc_huff_table */ typedef struct { JHUFF_TBL pub; /* public fields */ /* Extra data for Huffman encoder's use only */ unsigned int ehufco[256]; /* code for each symbol */ char ehufsi[256]; /* length of code for each symbol */ } JCHUFF_TBL; /* Marker writing */ struct jpeg_marker_writer { /* write_any_marker is exported for use by applications */ /* Probably only COM and APPn markers should be written */ JMETHOD(void, write_any_marker, (j_compress_ptr cinfo, int marker, JOCTET *dataptr, unsigned int datalen)); JMETHOD(void, write_file_header, (j_compress_ptr cinfo)); JMETHOD(void, write_frame_header, (j_compress_ptr cinfo)); JMETHOD(void, write_scan_header, (j_compress_ptr cinfo)); JMETHOD(void, write_file_trailer, (j_compress_ptr cinfo)); JMETHOD(void, write_tables_only, (j_compress_ptr cinfo)); }; /* Declarations for decompression modules */ /* Master control module */ struct jpeg_decomp_master { JMETHOD(void, prepare_for_pass, (j_decompress_ptr cinfo)); JMETHOD(void, finish_pass, (j_decompress_ptr cinfo)); /* State variables made visible to other modules */ boolean is_last_pass; /* True during last pass */ boolean eoi_processed; /* True if EOI marker already read */ }; /* Main buffer control (downsampled-data buffer) */ struct jpeg_d_main_controller { JMETHOD(void, start_pass, (j_decompress_ptr cinfo, J_BUF_MODE pass_mode)); JMETHOD(void, process_data, (j_decompress_ptr cinfo, JSAMPARRAY output_buf, JDIMENSION *out_row_ctr, JDIMENSION out_rows_avail)); }; /* Coefficient buffer control */ struct jpeg_d_coef_controller { JMETHOD(void, start_pass, (j_decompress_ptr cinfo, J_BUF_MODE pass_mode)); JMETHOD(boolean, decompress_data, (j_decompress_ptr cinfo, JSAMPIMAGE output_buf)); }; /* Decompression postprocessing (color quantization buffer control) */ struct jpeg_d_post_controller { JMETHOD(void, start_pass, (j_decompress_ptr cinfo, J_BUF_MODE pass_mode)); JMETHOD(void, post_process_data, (j_decompress_ptr cinfo, JSAMPIMAGE input_buf, JDIMENSION *in_row_group_ctr, JDIMENSION in_row_groups_avail, JSAMPARRAY output_buf, JDIMENSION *out_row_ctr, JDIMENSION out_rows_avail)); }; /* Marker reading & parsing */ typedef JMETHOD(boolean, marker_parser_method_ptr, (j_decompress_ptr cinfo)); /* Need not pass marker code since it is stored in cinfo->unread_marker. */ struct jpeg_marker_reader { JMETHOD(void, reset_marker_reader, (j_decompress_ptr cinfo)); /* Read markers until SOS or EOI. * Returns same codes as are defined for jpeg_read_header, * but HEADER_OK and HEADER_TABLES_ONLY merely indicate which marker type * stopped the scan --- further validation is needed to declare file OK. */ JMETHOD(int, read_markers, (j_decompress_ptr cinfo)); /* Read a restart marker --- exported for use by entropy decoder only */ marker_parser_method_ptr read_restart_marker; /* Application-overridable marker processing methods */ marker_parser_method_ptr process_COM; marker_parser_method_ptr process_APPn[16]; /* State of marker reader --- nominally internal, but applications * supplying COM or APPn handlers might like to know the state. */ boolean saw_SOI; /* found SOI? */ boolean saw_SOF; /* found SOF? */ int next_restart_num; /* next restart number expected (0-7) */ unsigned int discarded_bytes; /* # of bytes skipped looking for a marker */ }; /* Entropy decoding */ struct jpeg_entropy_decoder { JMETHOD(void, start_pass, (j_decompress_ptr cinfo)); JMETHOD(boolean, decode_mcu, (j_decompress_ptr cinfo, JBLOCKROW *MCU_data)); }; /* JDHUFF_TBL details made visible for jpeg_alloc_huff_table */ #define HUFF_LOOKAHEAD 8 /* # of bits of lookahead */ typedef struct { JHUFF_TBL pub; /* public fields */ /* Extra data for Huffman decoder's use only */ /* Basic tables: (element [0] of each array is unused) */ INT32 mincode[17]; /* smallest code of length k */ INT32 maxcode[18]; /* largest code of length k (-1 if none) */ /* (maxcode[17] is a sentinel to ensure huff_DECODE terminates) */ int valptr[17]; /* huffval[] index of 1st symbol of length k */ /* Lookahead tables: indexed by the next HUFF_LOOKAHEAD bits of * the input data stream. If the next Huffman code is no more * than HUFF_LOOKAHEAD bits long, we can obtain its length and * the corresponding symbol directly from these tables. */ int look_nbits[1< (b) ? (a) : (b)) #undef MIN #define MIN(a,b) ((a) < (b) ? (a) : (b)) /* We assume that right shift corresponds to signed division by 2 with * rounding towards minus infinity. This is correct for typical "arithmetic * shift" instructions that shift in copies of the sign bit. But some * C compilers implement >> with an unsigned shift. For these machines you * must define RIGHT_SHIFT_IS_UNSIGNED. * RIGHT_SHIFT provides a proper signed right shift of an INT32 quantity. * It is only applied with constant shift counts. SHIFT_TEMPS must be * included in the variables of any routine using RIGHT_SHIFT. */ #ifdef RIGHT_SHIFT_IS_UNSIGNED #define SHIFT_TEMPS INT32 shift_temp; #define RIGHT_SHIFT(x,shft) \ ((shift_temp = (x)) < 0 ? \ (shift_temp >> (shft)) | ((~((INT32) 0)) << (32-(shft))) : \ (shift_temp >> (shft))) #else #define SHIFT_TEMPS #define RIGHT_SHIFT(x,shft) ((x) >> (shft)) #endif /* Short forms of external names for systems with brain-damaged linkers. */ #ifdef NEED_SHORT_EXTERNAL_NAMES #define jinit_master_compress jICMaster #define jinit_c_main_controller jICMainC #define jinit_c_prep_controller jICPrepC #define jinit_c_coef_controller jICCoefC #define jinit_color_converter jICColor #define jinit_downsampler jIDownsampler #define jinit_forward_dct jIFDCT #define jinit_huff_encoder jIHEncoder #define jinit_marker_writer jIMWriter #define jinit_master_decompress jIDMaster #define jinit_d_main_controller jIDMainC #define jinit_d_coef_controller jIDCoefC #define jinit_d_post_controller jIDPostC #define jinit_marker_reader jIMReader #define jinit_huff_decoder jIHDecoder #define jinit_inverse_dct jIIDCT #define jinit_upsampler jIUpsampler #define jinit_color_deconverter jIDColor #define jinit_1pass_quantizer jI1Quant #define jinit_2pass_quantizer jI2Quant #define jinit_memory_mgr jIMemMgr #define jdiv_round_up jDivRound #define jround_up jRound #define jcopy_sample_rows jCopySamples #define jcopy_block_row jCopyBlocks #define jzero_far jZeroFar #endif /* NEED_SHORT_EXTERNAL_NAMES */ /* Compression module initialization routines */ EXTERN void jinit_master_compress JPP((j_compress_ptr cinfo)); EXTERN void jinit_c_main_controller JPP((j_compress_ptr cinfo, boolean need_full_buffer)); EXTERN void jinit_c_prep_controller JPP((j_compress_ptr cinfo, boolean need_full_buffer)); EXTERN void jinit_c_coef_controller JPP((j_compress_ptr cinfo, boolean need_full_buffer)); EXTERN void jinit_color_converter JPP((j_compress_ptr cinfo)); EXTERN void jinit_downsampler JPP((j_compress_ptr cinfo)); EXTERN void jinit_forward_dct JPP((j_compress_ptr cinfo)); EXTERN void jinit_huff_encoder JPP((j_compress_ptr cinfo)); EXTERN void jinit_marker_writer JPP((j_compress_ptr cinfo)); /* Decompression module initialization routines */ EXTERN void jinit_master_decompress JPP((j_decompress_ptr cinfo)); EXTERN void jinit_d_main_controller JPP((j_decompress_ptr cinfo, boolean need_full_buffer)); EXTERN void jinit_d_coef_controller JPP((j_decompress_ptr cinfo, boolean need_full_buffer)); EXTERN void jinit_d_post_controller JPP((j_decompress_ptr cinfo, boolean need_full_buffer)); EXTERN void jinit_marker_reader JPP((j_decompress_ptr cinfo)); EXTERN void jinit_huff_decoder JPP((j_decompress_ptr cinfo)); EXTERN void jinit_inverse_dct JPP((j_decompress_ptr cinfo)); EXTERN void jinit_upsampler JPP((j_decompress_ptr cinfo)); EXTERN void jinit_color_deconverter JPP((j_decompress_ptr cinfo)); EXTERN void jinit_1pass_quantizer JPP((j_decompress_ptr cinfo)); EXTERN void jinit_2pass_quantizer JPP((j_decompress_ptr cinfo)); /* Memory manager initialization */ EXTERN void jinit_memory_mgr JPP((j_common_ptr cinfo)); /* Utility routines in jutils.c */ EXTERN long jdiv_round_up JPP((long a, long b)); EXTERN long jround_up JPP((long a, long b)); EXTERN void jcopy_sample_rows JPP((JSAMPARRAY input_array, int source_row, JSAMPARRAY output_array, int dest_row, int num_rows, JDIMENSION num_cols)); EXTERN void jcopy_block_row JPP((JBLOCKROW input_row, JBLOCKROW output_row, JDIMENSION num_blocks)); EXTERN void jzero_far JPP((void FAR * target, size_t bytestozero)); /* Suppress undefined-structure complaints if necessary. */ #ifdef INCOMPLETE_TYPES_BROKEN #ifndef AM_MEMORY_MANAGER /* only jmemmgr.c defines these */ struct jvirt_sarray_control { long dummy; }; struct jvirt_barray_control { long dummy; }; #endif #endif /* INCOMPLETE_TYPES_BROKEN */