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Tidy a bit

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kris 2021-11-01 12:10:02 +00:00
parent 0c588f7489
commit 24644658cb
1 changed files with 7 additions and 12 deletions
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19
dither.pyx
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@ -2,8 +2,6 @@
# cython: profile=False
cimport cython
import colour
import math
import numpy as np
from libc.stdlib cimport malloc, free
@ -52,7 +50,8 @@ cdef int dither_bounds_yb(Dither *dither, int y_res, int y) nogil:
return yb
cdef inline unsigned char lookahead_pixels(unsigned char last_pixel_nbit, unsigned int next_pixels, int lookahead) nogil:
cdef inline unsigned char lookahead_pixels(
unsigned char last_pixel_nbit, unsigned int next_pixels, int lookahead) nogil:
"""Compute all possible n-bit palette values for upcoming pixels, given x coord and state of n pixels to the left.
Args:
@ -97,14 +96,14 @@ cdef int dither_lookahead(Dither* dither, float[:, :, ::1] palette_cam16, float[
cdef float total_error
cdef unsigned char next_pixels
cdef int phase
cdef float[::1] lah_cam16ucs
# Don't bother dithering past the lookahead horizon or edge of screen.
cdef int xxr = min(x + lookahead, x_res)
cdef int lah_shape1 = xxr - x
cdef int lah_shape2 = 3
# XXX use a memoryview
cdef float *lah_image_rgb = <float *> malloc(lah_shape1 * lah_shape2 * sizeof(float))
cdef float[::1] lah_cam16ucs
# For each 2**lookahead possibilities for the on/off state of the next lookahead pixels, apply error diffusion
# and compute the total squared error to the source image. Since we only have two possible colours for each
@ -135,7 +134,8 @@ cdef int dither_lookahead(Dither* dither, float[:, :, ::1] palette_cam16, float[
apply_one_line(dither, xl, xr, j, lah_image_rgb, lah_shape2, quant_error)
lah_cam16ucs = convert_rgb_to_cam16ucs(
rgb_to_cam16ucs, lah_image_rgb[j*lah_shape2], lah_image_rgb[j*lah_shape2+1], lah_image_rgb[j*lah_shape2+2])
rgb_to_cam16ucs, lah_image_rgb[j*lah_shape2], lah_image_rgb[j*lah_shape2+1],
lah_image_rgb[j*lah_shape2+2])
total_error += colour_distance_squared(lah_cam16ucs, palette_cam16[next_pixels, phase])
if total_error >= best_error:
@ -208,10 +208,6 @@ cdef void apply(Dither* dither, int x_res, int y_res, int x, int y, float[:,:,::
cdef int xr = dither_bounds_xr(dither, x_res, x)
cdef float error_fraction
# We could avoid clipping here, i.e. allow RGB values to extend beyond
# 0..255 to capture a larger range of residual error. This is faster
# but seems to reduce image quality.
# TODO: is this still true?
for i in range(yt, yb):
for j in range(xl, xr):
error_fraction = dither.pattern[(i - y) * dither.x_shape + j - x + dither.x_origin]
@ -297,8 +293,7 @@ def dither_image(screen, float[:, :, ::1] image_rgb, dither, int lookahead, unsi
for j in range(cdither.x_shape):
cdither.pattern[i * cdither.x_shape + j] = dither.PATTERN[i, j]
cdef (unsigned char)[:, ::1] image_nbit = np.empty(
(image_rgb.shape[0], image_rgb.shape[1]), dtype=np.uint8)
cdef (unsigned char)[:, ::1] image_nbit = np.empty((image_rgb.shape[0], image_rgb.shape[1]), dtype=np.uint8)
for y in range(yres):
if verbose: