1 /*
2 * Copyright (c) 2015 Stupeflix
3 *
4 * This file is part of FFmpeg.
5 *
6 * FFmpeg is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU Lesser General Public
8 * License as published by the Free Software Foundation; either
9 * version 2.1 of the License, or (at your option) any later version.
10 *
11 * FFmpeg is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14 * Lesser General Public License for more details.
15 *
16 * You should have received a copy of the GNU Lesser General Public
17 * License along with FFmpeg; if not, write to the Free Software
18 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
19 */
20
21 /**
22 * @file
23 * Use a palette to downsample an input video stream.
24 */
25
26 #include "libavutil/bprint.h"
27 #include "libavutil/internal.h"
28 #include "libavutil/opt.h"
29 #include "libavutil/qsort.h"
30 #include "avfilter.h"
31 #include "filters.h"
32 #include "framesync.h"
33 #include "internal.h"
34
35 enum dithering_mode {
36 DITHERING_NONE,
37 DITHERING_BAYER,
38 DITHERING_HECKBERT,
39 DITHERING_FLOYD_STEINBERG,
40 DITHERING_SIERRA2,
41 DITHERING_SIERRA2_4A,
42 NB_DITHERING
43 };
44
45 enum color_search_method {
46 COLOR_SEARCH_NNS_ITERATIVE,
47 COLOR_SEARCH_NNS_RECURSIVE,
48 COLOR_SEARCH_BRUTEFORCE,
49 NB_COLOR_SEARCHES
50 };
51
52 enum diff_mode {
53 DIFF_MODE_NONE,
54 DIFF_MODE_RECTANGLE,
55 NB_DIFF_MODE
56 };
57
58 struct color_node {
59 uint8_t val[4];
60 uint8_t palette_id;
61 int split;
62 int left_id, right_id;
63 };
64
65 #define NBITS 5
66 #define CACHE_SIZE (1<<(3*NBITS))
67
68 struct cached_color {
69 uint32_t color;
70 uint8_t pal_entry;
71 };
72
73 struct cache_node {
74 struct cached_color *entries;
75 int nb_entries;
76 };
77
78 struct PaletteUseContext;
79
80 typedef int (*set_frame_func)(struct PaletteUseContext *s, AVFrame *out, AVFrame *in,
81 int x_start, int y_start, int width, int height);
82
83 typedef struct PaletteUseContext {
84 const AVClass *class;
85 FFFrameSync fs;
86 struct cache_node cache[CACHE_SIZE]; /* lookup cache */
87 struct color_node map[AVPALETTE_COUNT]; /* 3D-Tree (KD-Tree with K=3) for reverse colormap */
88 uint32_t palette[AVPALETTE_COUNT];
89 int transparency_index; /* index in the palette of transparency. -1 if there is no transparency in the palette. */
90 int trans_thresh;
91 int palette_loaded;
92 int dither;
93 int new;
94 set_frame_func set_frame;
95 int bayer_scale;
96 int ordered_dither[8*8];
97 int diff_mode;
98 AVFrame *last_in;
99 AVFrame *last_out;
100
101 /* debug options */
102 char *dot_filename;
103 int color_search_method;
104 int calc_mean_err;
105 uint64_t total_mean_err;
106 int debug_accuracy;
107 } PaletteUseContext;
108
109 #define OFFSET(x) offsetof(PaletteUseContext, x)
110 #define FLAGS AV_OPT_FLAG_FILTERING_PARAM|AV_OPT_FLAG_VIDEO_PARAM
111 static const AVOption paletteuse_options[] = {
112 { "dither", "select dithering mode", OFFSET(dither), AV_OPT_TYPE_INT, {.i64=DITHERING_SIERRA2_4A}, 0, NB_DITHERING-1, FLAGS, "dithering_mode" },
113 { "bayer", "ordered 8x8 bayer dithering (deterministic)", 0, AV_OPT_TYPE_CONST, {.i64=DITHERING_BAYER}, INT_MIN, INT_MAX, FLAGS, "dithering_mode" },
114 { "heckbert", "dithering as defined by Paul Heckbert in 1982 (simple error diffusion)", 0, AV_OPT_TYPE_CONST, {.i64=DITHERING_HECKBERT}, INT_MIN, INT_MAX, FLAGS, "dithering_mode" },
115 { "floyd_steinberg", "Floyd and Steingberg dithering (error diffusion)", 0, AV_OPT_TYPE_CONST, {.i64=DITHERING_FLOYD_STEINBERG}, INT_MIN, INT_MAX, FLAGS, "dithering_mode" },
116 { "sierra2", "Frankie Sierra dithering v2 (error diffusion)", 0, AV_OPT_TYPE_CONST, {.i64=DITHERING_SIERRA2}, INT_MIN, INT_MAX, FLAGS, "dithering_mode" },
117 { "sierra2_4a", "Frankie Sierra dithering v2 \"Lite\" (error diffusion)", 0, AV_OPT_TYPE_CONST, {.i64=DITHERING_SIERRA2_4A}, INT_MIN, INT_MAX, FLAGS, "dithering_mode" },
118 { "bayer_scale", "set scale for bayer dithering", OFFSET(bayer_scale), AV_OPT_TYPE_INT, {.i64=2}, 0, 5, FLAGS },
119 { "diff_mode", "set frame difference mode", OFFSET(diff_mode), AV_OPT_TYPE_INT, {.i64=DIFF_MODE_NONE}, 0, NB_DIFF_MODE-1, FLAGS, "diff_mode" },
120 { "rectangle", "process smallest different rectangle", 0, AV_OPT_TYPE_CONST, {.i64=DIFF_MODE_RECTANGLE}, INT_MIN, INT_MAX, FLAGS, "diff_mode" },
121 { "new", "take new palette for each output frame", OFFSET(new), AV_OPT_TYPE_BOOL, {.i64=0}, 0, 1, FLAGS },
122 { "alpha_threshold", "set the alpha threshold for transparency", OFFSET(trans_thresh), AV_OPT_TYPE_INT, {.i64=128}, 0, 255, FLAGS },
123
124 /* following are the debug options, not part of the official API */
125 { "debug_kdtree", "save Graphviz graph of the kdtree in specified file", OFFSET(dot_filename), AV_OPT_TYPE_STRING, {.str=NULL}, 0, 0, FLAGS },
126 { "color_search", "set reverse colormap color search method", OFFSET(color_search_method), AV_OPT_TYPE_INT, {.i64=COLOR_SEARCH_NNS_ITERATIVE}, 0, NB_COLOR_SEARCHES-1, FLAGS, "search" },
127 { "nns_iterative", "iterative search", 0, AV_OPT_TYPE_CONST, {.i64=COLOR_SEARCH_NNS_ITERATIVE}, INT_MIN, INT_MAX, FLAGS, "search" },
128 { "nns_recursive", "recursive search", 0, AV_OPT_TYPE_CONST, {.i64=COLOR_SEARCH_NNS_RECURSIVE}, INT_MIN, INT_MAX, FLAGS, "search" },
129 { "bruteforce", "brute-force into the palette", 0, AV_OPT_TYPE_CONST, {.i64=COLOR_SEARCH_BRUTEFORCE}, INT_MIN, INT_MAX, FLAGS, "search" },
130 { "mean_err", "compute and print mean error", OFFSET(calc_mean_err), AV_OPT_TYPE_BOOL, {.i64=0}, 0, 1, FLAGS },
131 { "debug_accuracy", "test color search accuracy", OFFSET(debug_accuracy), AV_OPT_TYPE_BOOL, {.i64=0}, 0, 1, FLAGS },
132 { NULL }
133 };
134
135 AVFILTER_DEFINE_CLASS(paletteuse);
136
137 static int load_apply_palette(FFFrameSync *fs);
138
query_formats(AVFilterContext * ctx)139 static int query_formats(AVFilterContext *ctx)
140 {
141 static const enum AVPixelFormat in_fmts[] = {AV_PIX_FMT_RGB32, AV_PIX_FMT_NONE};
142 static const enum AVPixelFormat inpal_fmts[] = {AV_PIX_FMT_RGB32, AV_PIX_FMT_NONE};
143 static const enum AVPixelFormat out_fmts[] = {AV_PIX_FMT_PAL8, AV_PIX_FMT_NONE};
144 int ret;
145 AVFilterFormats *in = ff_make_format_list(in_fmts);
146 AVFilterFormats *inpal = ff_make_format_list(inpal_fmts);
147 AVFilterFormats *out = ff_make_format_list(out_fmts);
148 if (!in || !inpal || !out) {
149 av_freep(&in);
150 av_freep(&inpal);
151 av_freep(&out);
152 return AVERROR(ENOMEM);
153 }
154 if ((ret = ff_formats_ref(in , &ctx->inputs[0]->out_formats)) < 0 ||
155 (ret = ff_formats_ref(inpal, &ctx->inputs[1]->out_formats)) < 0 ||
156 (ret = ff_formats_ref(out , &ctx->outputs[0]->in_formats)) < 0)
157 return ret;
158 return 0;
159 }
160
dither_color(uint32_t px,int er,int eg,int eb,int scale,int shift)161 static av_always_inline int dither_color(uint32_t px, int er, int eg, int eb, int scale, int shift)
162 {
163 return av_clip_uint8( px >> 24 ) << 24
164 | av_clip_uint8((px >> 16 & 0xff) + ((er * scale) / (1<<shift))) << 16
165 | av_clip_uint8((px >> 8 & 0xff) + ((eg * scale) / (1<<shift))) << 8
166 | av_clip_uint8((px & 0xff) + ((eb * scale) / (1<<shift)));
167 }
168
diff(const uint8_t * c1,const uint8_t * c2,const int trans_thresh)169 static av_always_inline int diff(const uint8_t *c1, const uint8_t *c2, const int trans_thresh)
170 {
171 // XXX: try L*a*b with CIE76 (dL*dL + da*da + db*db)
172 const int dr = c1[1] - c2[1];
173 const int dg = c1[2] - c2[2];
174 const int db = c1[3] - c2[3];
175
176 if (c1[0] < trans_thresh && c2[0] < trans_thresh) {
177 return 0;
178 } else if (c1[0] >= trans_thresh && c2[0] >= trans_thresh) {
179 return dr*dr + dg*dg + db*db;
180 } else {
181 return 255*255 + 255*255 + 255*255;
182 }
183 }
184
colormap_nearest_bruteforce(const uint32_t * palette,const uint8_t * argb,const int trans_thresh)185 static av_always_inline uint8_t colormap_nearest_bruteforce(const uint32_t *palette, const uint8_t *argb, const int trans_thresh)
186 {
187 int i, pal_id = -1, min_dist = INT_MAX;
188
189 for (i = 0; i < AVPALETTE_COUNT; i++) {
190 const uint32_t c = palette[i];
191
192 if (c >> 24 >= trans_thresh) { // ignore transparent entry
193 const uint8_t palargb[] = {
194 palette[i]>>24 & 0xff,
195 palette[i]>>16 & 0xff,
196 palette[i]>> 8 & 0xff,
197 palette[i] & 0xff,
198 };
199 const int d = diff(palargb, argb, trans_thresh);
200 if (d < min_dist) {
201 pal_id = i;
202 min_dist = d;
203 }
204 }
205 }
206 return pal_id;
207 }
208
209 /* Recursive form, simpler but a bit slower. Kept for reference. */
210 struct nearest_color {
211 int node_pos;
212 int dist_sqd;
213 };
214
colormap_nearest_node(const struct color_node * map,const int node_pos,const uint8_t * target,const int trans_thresh,struct nearest_color * nearest)215 static void colormap_nearest_node(const struct color_node *map,
216 const int node_pos,
217 const uint8_t *target,
218 const int trans_thresh,
219 struct nearest_color *nearest)
220 {
221 const struct color_node *kd = map + node_pos;
222 const int s = kd->split;
223 int dx, nearer_kd_id, further_kd_id;
224 const uint8_t *current = kd->val;
225 const int current_to_target = diff(target, current, trans_thresh);
226
227 if (current_to_target < nearest->dist_sqd) {
228 nearest->node_pos = node_pos;
229 nearest->dist_sqd = current_to_target;
230 }
231
232 if (kd->left_id != -1 || kd->right_id != -1) {
233 dx = target[s] - current[s];
234
235 if (dx <= 0) nearer_kd_id = kd->left_id, further_kd_id = kd->right_id;
236 else nearer_kd_id = kd->right_id, further_kd_id = kd->left_id;
237
238 if (nearer_kd_id != -1)
239 colormap_nearest_node(map, nearer_kd_id, target, trans_thresh, nearest);
240
241 if (further_kd_id != -1 && dx*dx < nearest->dist_sqd)
242 colormap_nearest_node(map, further_kd_id, target, trans_thresh, nearest);
243 }
244 }
245
colormap_nearest_recursive(const struct color_node * node,const uint8_t * rgb,const int trans_thresh)246 static av_always_inline uint8_t colormap_nearest_recursive(const struct color_node *node, const uint8_t *rgb, const int trans_thresh)
247 {
248 struct nearest_color res = {.dist_sqd = INT_MAX, .node_pos = -1};
249 colormap_nearest_node(node, 0, rgb, trans_thresh, &res);
250 return node[res.node_pos].palette_id;
251 }
252
253 struct stack_node {
254 int color_id;
255 int dx2;
256 };
257
colormap_nearest_iterative(const struct color_node * root,const uint8_t * target,const int trans_thresh)258 static av_always_inline uint8_t colormap_nearest_iterative(const struct color_node *root, const uint8_t *target, const int trans_thresh)
259 {
260 int pos = 0, best_node_id = -1, best_dist = INT_MAX, cur_color_id = 0;
261 struct stack_node nodes[16];
262 struct stack_node *node = &nodes[0];
263
264 for (;;) {
265
266 const struct color_node *kd = &root[cur_color_id];
267 const uint8_t *current = kd->val;
268 const int current_to_target = diff(target, current, trans_thresh);
269
270 /* Compare current color node to the target and update our best node if
271 * it's actually better. */
272 if (current_to_target < best_dist) {
273 best_node_id = cur_color_id;
274 if (!current_to_target)
275 goto end; // exact match, we can return immediately
276 best_dist = current_to_target;
277 }
278
279 /* Check if it's not a leaf */
280 if (kd->left_id != -1 || kd->right_id != -1) {
281 const int split = kd->split;
282 const int dx = target[split] - current[split];
283 int nearer_kd_id, further_kd_id;
284
285 /* Define which side is the most interesting. */
286 if (dx <= 0) nearer_kd_id = kd->left_id, further_kd_id = kd->right_id;
287 else nearer_kd_id = kd->right_id, further_kd_id = kd->left_id;
288
289 if (nearer_kd_id != -1) {
290 if (further_kd_id != -1) {
291 /* Here, both paths are defined, so we push a state for
292 * when we are going back. */
293 node->color_id = further_kd_id;
294 node->dx2 = dx*dx;
295 pos++;
296 node++;
297 }
298 /* We can now update current color with the most probable path
299 * (no need to create a state since there is nothing to save
300 * anymore). */
301 cur_color_id = nearer_kd_id;
302 continue;
303 } else if (dx*dx < best_dist) {
304 /* The nearest path isn't available, so there is only one path
305 * possible and it's the least probable. We enter it only if the
306 * distance from the current point to the hyper rectangle is
307 * less than our best distance. */
308 cur_color_id = further_kd_id;
309 continue;
310 }
311 }
312
313 /* Unstack as much as we can, typically as long as the least probable
314 * branch aren't actually probable. */
315 do {
316 if (--pos < 0)
317 goto end;
318 node--;
319 } while (node->dx2 >= best_dist);
320
321 /* We got a node where the least probable branch might actually contain
322 * a relevant color. */
323 cur_color_id = node->color_id;
324 }
325
326 end:
327 return root[best_node_id].palette_id;
328 }
329
330 #define COLORMAP_NEAREST(search, palette, root, target, trans_thresh) \
331 search == COLOR_SEARCH_NNS_ITERATIVE ? colormap_nearest_iterative(root, target, trans_thresh) : \
332 search == COLOR_SEARCH_NNS_RECURSIVE ? colormap_nearest_recursive(root, target, trans_thresh) : \
333 colormap_nearest_bruteforce(palette, target, trans_thresh)
334
335 /**
336 * Check if the requested color is in the cache already. If not, find it in the
337 * color tree and cache it.
338 * Note: a, r, g, and b are the components of color, but are passed as well to avoid
339 * recomputing them (they are generally computed by the caller for other uses).
340 */
color_get(PaletteUseContext * s,uint32_t color,uint8_t a,uint8_t r,uint8_t g,uint8_t b,const enum color_search_method search_method)341 static av_always_inline int color_get(PaletteUseContext *s, uint32_t color,
342 uint8_t a, uint8_t r, uint8_t g, uint8_t b,
343 const enum color_search_method search_method)
344 {
345 int i;
346 const uint8_t argb_elts[] = {a, r, g, b};
347 const uint8_t rhash = r & ((1<<NBITS)-1);
348 const uint8_t ghash = g & ((1<<NBITS)-1);
349 const uint8_t bhash = b & ((1<<NBITS)-1);
350 const unsigned hash = rhash<<(NBITS*2) | ghash<<NBITS | bhash;
351 struct cache_node *node = &s->cache[hash];
352 struct cached_color *e;
353
354 // first, check for transparency
355 if (a < s->trans_thresh && s->transparency_index >= 0) {
356 return s->transparency_index;
357 }
358
359 for (i = 0; i < node->nb_entries; i++) {
360 e = &node->entries[i];
361 if (e->color == color)
362 return e->pal_entry;
363 }
364
365 e = av_dynarray2_add((void**)&node->entries, &node->nb_entries,
366 sizeof(*node->entries), NULL);
367 if (!e)
368 return AVERROR(ENOMEM);
369 e->color = color;
370 e->pal_entry = COLORMAP_NEAREST(search_method, s->palette, s->map, argb_elts, s->trans_thresh);
371
372 return e->pal_entry;
373 }
374
get_dst_color_err(PaletteUseContext * s,uint32_t c,int * er,int * eg,int * eb,const enum color_search_method search_method)375 static av_always_inline int get_dst_color_err(PaletteUseContext *s,
376 uint32_t c, int *er, int *eg, int *eb,
377 const enum color_search_method search_method)
378 {
379 const uint8_t a = c >> 24 & 0xff;
380 const uint8_t r = c >> 16 & 0xff;
381 const uint8_t g = c >> 8 & 0xff;
382 const uint8_t b = c & 0xff;
383 uint32_t dstc;
384 const int dstx = color_get(s, c, a, r, g, b, search_method);
385 if (dstx < 0)
386 return dstx;
387 dstc = s->palette[dstx];
388 *er = r - (dstc >> 16 & 0xff);
389 *eg = g - (dstc >> 8 & 0xff);
390 *eb = b - (dstc & 0xff);
391 return dstx;
392 }
393
set_frame(PaletteUseContext * s,AVFrame * out,AVFrame * in,int x_start,int y_start,int w,int h,enum dithering_mode dither,const enum color_search_method search_method)394 static av_always_inline int set_frame(PaletteUseContext *s, AVFrame *out, AVFrame *in,
395 int x_start, int y_start, int w, int h,
396 enum dithering_mode dither,
397 const enum color_search_method search_method)
398 {
399 int x, y;
400 const int src_linesize = in ->linesize[0] >> 2;
401 const int dst_linesize = out->linesize[0];
402 uint32_t *src = ((uint32_t *)in ->data[0]) + y_start*src_linesize;
403 uint8_t *dst = out->data[0] + y_start*dst_linesize;
404
405 w += x_start;
406 h += y_start;
407
408 for (y = y_start; y < h; y++) {
409 for (x = x_start; x < w; x++) {
410 int er, eg, eb;
411
412 if (dither == DITHERING_BAYER) {
413 const int d = s->ordered_dither[(y & 7)<<3 | (x & 7)];
414 const uint8_t a8 = src[x] >> 24 & 0xff;
415 const uint8_t r8 = src[x] >> 16 & 0xff;
416 const uint8_t g8 = src[x] >> 8 & 0xff;
417 const uint8_t b8 = src[x] & 0xff;
418 const uint8_t r = av_clip_uint8(r8 + d);
419 const uint8_t g = av_clip_uint8(g8 + d);
420 const uint8_t b = av_clip_uint8(b8 + d);
421 const int color = color_get(s, src[x], a8, r, g, b, search_method);
422
423 if (color < 0)
424 return color;
425 dst[x] = color;
426
427 } else if (dither == DITHERING_HECKBERT) {
428 const int right = x < w - 1, down = y < h - 1;
429 const int color = get_dst_color_err(s, src[x], &er, &eg, &eb, search_method);
430
431 if (color < 0)
432 return color;
433 dst[x] = color;
434
435 if (right) src[ x + 1] = dither_color(src[ x + 1], er, eg, eb, 3, 3);
436 if ( down) src[src_linesize + x ] = dither_color(src[src_linesize + x ], er, eg, eb, 3, 3);
437 if (right && down) src[src_linesize + x + 1] = dither_color(src[src_linesize + x + 1], er, eg, eb, 2, 3);
438
439 } else if (dither == DITHERING_FLOYD_STEINBERG) {
440 const int right = x < w - 1, down = y < h - 1, left = x > x_start;
441 const int color = get_dst_color_err(s, src[x], &er, &eg, &eb, search_method);
442
443 if (color < 0)
444 return color;
445 dst[x] = color;
446
447 if (right) src[ x + 1] = dither_color(src[ x + 1], er, eg, eb, 7, 4);
448 if (left && down) src[src_linesize + x - 1] = dither_color(src[src_linesize + x - 1], er, eg, eb, 3, 4);
449 if ( down) src[src_linesize + x ] = dither_color(src[src_linesize + x ], er, eg, eb, 5, 4);
450 if (right && down) src[src_linesize + x + 1] = dither_color(src[src_linesize + x + 1], er, eg, eb, 1, 4);
451
452 } else if (dither == DITHERING_SIERRA2) {
453 const int right = x < w - 1, down = y < h - 1, left = x > x_start;
454 const int right2 = x < w - 2, left2 = x > x_start + 1;
455 const int color = get_dst_color_err(s, src[x], &er, &eg, &eb, search_method);
456
457 if (color < 0)
458 return color;
459 dst[x] = color;
460
461 if (right) src[ x + 1] = dither_color(src[ x + 1], er, eg, eb, 4, 4);
462 if (right2) src[ x + 2] = dither_color(src[ x + 2], er, eg, eb, 3, 4);
463
464 if (down) {
465 if (left2) src[ src_linesize + x - 2] = dither_color(src[ src_linesize + x - 2], er, eg, eb, 1, 4);
466 if (left) src[ src_linesize + x - 1] = dither_color(src[ src_linesize + x - 1], er, eg, eb, 2, 4);
467 if (1) src[ src_linesize + x ] = dither_color(src[ src_linesize + x ], er, eg, eb, 3, 4);
468 if (right) src[ src_linesize + x + 1] = dither_color(src[ src_linesize + x + 1], er, eg, eb, 2, 4);
469 if (right2) src[ src_linesize + x + 2] = dither_color(src[ src_linesize + x + 2], er, eg, eb, 1, 4);
470 }
471
472 } else if (dither == DITHERING_SIERRA2_4A) {
473 const int right = x < w - 1, down = y < h - 1, left = x > x_start;
474 const int color = get_dst_color_err(s, src[x], &er, &eg, &eb, search_method);
475
476 if (color < 0)
477 return color;
478 dst[x] = color;
479
480 if (right) src[ x + 1] = dither_color(src[ x + 1], er, eg, eb, 2, 2);
481 if (left && down) src[src_linesize + x - 1] = dither_color(src[src_linesize + x - 1], er, eg, eb, 1, 2);
482 if ( down) src[src_linesize + x ] = dither_color(src[src_linesize + x ], er, eg, eb, 1, 2);
483
484 } else {
485 const uint8_t a = src[x] >> 24 & 0xff;
486 const uint8_t r = src[x] >> 16 & 0xff;
487 const uint8_t g = src[x] >> 8 & 0xff;
488 const uint8_t b = src[x] & 0xff;
489 const int color = color_get(s, src[x], a, r, g, b, search_method);
490
491 if (color < 0)
492 return color;
493 dst[x] = color;
494 }
495 }
496 src += src_linesize;
497 dst += dst_linesize;
498 }
499 return 0;
500 }
501
502 #define INDENT 4
disp_node(AVBPrint * buf,const struct color_node * map,int parent_id,int node_id,int depth)503 static void disp_node(AVBPrint *buf,
504 const struct color_node *map,
505 int parent_id, int node_id,
506 int depth)
507 {
508 const struct color_node *node = &map[node_id];
509 const uint32_t fontcolor = node->val[1] > 0x50 &&
510 node->val[2] > 0x50 &&
511 node->val[3] > 0x50 ? 0 : 0xffffff;
512 const int rgb_comp = node->split - 1;
513 av_bprintf(buf, "%*cnode%d ["
514 "label=\"%c%02X%c%02X%c%02X%c\" "
515 "fillcolor=\"#%02x%02x%02x\" "
516 "fontcolor=\"#%06"PRIX32"\"]\n",
517 depth*INDENT, ' ', node->palette_id,
518 "[ "[rgb_comp], node->val[1],
519 "][ "[rgb_comp], node->val[2],
520 " ]["[rgb_comp], node->val[3],
521 " ]"[rgb_comp],
522 node->val[1], node->val[2], node->val[3],
523 fontcolor);
524 if (parent_id != -1)
525 av_bprintf(buf, "%*cnode%d -> node%d\n", depth*INDENT, ' ',
526 map[parent_id].palette_id, node->palette_id);
527 if (node->left_id != -1) disp_node(buf, map, node_id, node->left_id, depth + 1);
528 if (node->right_id != -1) disp_node(buf, map, node_id, node->right_id, depth + 1);
529 }
530
531 // debug_kdtree=kdtree.dot -> dot -Tpng kdtree.dot > kdtree.png
disp_tree(const struct color_node * node,const char * fname)532 static int disp_tree(const struct color_node *node, const char *fname)
533 {
534 AVBPrint buf;
535 FILE *f = av_fopen_utf8(fname, "w");
536
537 if (!f) {
538 int ret = AVERROR(errno);
539 av_log(NULL, AV_LOG_ERROR, "Cannot open file '%s' for writing: %s\n",
540 fname, av_err2str(ret));
541 return ret;
542 }
543
544 av_bprint_init(&buf, 0, AV_BPRINT_SIZE_UNLIMITED);
545
546 av_bprintf(&buf, "digraph {\n");
547 av_bprintf(&buf, " node [style=filled fontsize=10 shape=box]\n");
548 disp_node(&buf, node, -1, 0, 0);
549 av_bprintf(&buf, "}\n");
550
551 fwrite(buf.str, 1, buf.len, f);
552 fclose(f);
553 av_bprint_finalize(&buf, NULL);
554 return 0;
555 }
556
debug_accuracy(const struct color_node * node,const uint32_t * palette,const int trans_thresh,const enum color_search_method search_method)557 static int debug_accuracy(const struct color_node *node, const uint32_t *palette, const int trans_thresh,
558 const enum color_search_method search_method)
559 {
560 int r, g, b, ret = 0;
561
562 for (r = 0; r < 256; r++) {
563 for (g = 0; g < 256; g++) {
564 for (b = 0; b < 256; b++) {
565 const uint8_t argb[] = {0xff, r, g, b};
566 const int r1 = COLORMAP_NEAREST(search_method, palette, node, argb, trans_thresh);
567 const int r2 = colormap_nearest_bruteforce(palette, argb, trans_thresh);
568 if (r1 != r2) {
569 const uint32_t c1 = palette[r1];
570 const uint32_t c2 = palette[r2];
571 const uint8_t palargb1[] = { 0xff, c1>>16 & 0xff, c1>> 8 & 0xff, c1 & 0xff };
572 const uint8_t palargb2[] = { 0xff, c2>>16 & 0xff, c2>> 8 & 0xff, c2 & 0xff };
573 const int d1 = diff(palargb1, argb, trans_thresh);
574 const int d2 = diff(palargb2, argb, trans_thresh);
575 if (d1 != d2) {
576 av_log(NULL, AV_LOG_ERROR,
577 "/!\\ %02X%02X%02X: %d ! %d (%06"PRIX32" ! %06"PRIX32") / dist: %d ! %d\n",
578 r, g, b, r1, r2, c1 & 0xffffff, c2 & 0xffffff, d1, d2);
579 ret = 1;
580 }
581 }
582 }
583 }
584 }
585 return ret;
586 }
587
588 struct color {
589 uint32_t value;
590 uint8_t pal_id;
591 };
592
593 struct color_rect {
594 uint8_t min[3];
595 uint8_t max[3];
596 };
597
598 typedef int (*cmp_func)(const void *, const void *);
599
600 #define DECLARE_CMP_FUNC(name, pos) \
601 static int cmp_##name(const void *pa, const void *pb) \
602 { \
603 const struct color *a = pa; \
604 const struct color *b = pb; \
605 return (a->value >> (8 * (3 - (pos))) & 0xff) \
606 - (b->value >> (8 * (3 - (pos))) & 0xff); \
607 }
608
609 DECLARE_CMP_FUNC(a, 0)
610 DECLARE_CMP_FUNC(r, 1)
611 DECLARE_CMP_FUNC(g, 2)
612 DECLARE_CMP_FUNC(b, 3)
613
614 static const cmp_func cmp_funcs[] = {cmp_a, cmp_r, cmp_g, cmp_b};
615
get_next_color(const uint8_t * color_used,const uint32_t * palette,const int trans_thresh,int * component,const struct color_rect * box)616 static int get_next_color(const uint8_t *color_used, const uint32_t *palette,
617 const int trans_thresh,
618 int *component, const struct color_rect *box)
619 {
620 int wr, wg, wb;
621 int i, longest = 0;
622 unsigned nb_color = 0;
623 struct color_rect ranges;
624 struct color tmp_pal[256];
625 cmp_func cmpf;
626
627 ranges.min[0] = ranges.min[1] = ranges.min[2] = 0xff;
628 ranges.max[0] = ranges.max[1] = ranges.max[2] = 0x00;
629
630 for (i = 0; i < AVPALETTE_COUNT; i++) {
631 const uint32_t c = palette[i];
632 const uint8_t a = c >> 24 & 0xff;
633 const uint8_t r = c >> 16 & 0xff;
634 const uint8_t g = c >> 8 & 0xff;
635 const uint8_t b = c & 0xff;
636
637 if (a < trans_thresh) {
638 continue;
639 }
640
641 if (color_used[i] || (a != 0xff) ||
642 r < box->min[0] || g < box->min[1] || b < box->min[2] ||
643 r > box->max[0] || g > box->max[1] || b > box->max[2])
644 continue;
645
646 if (r < ranges.min[0]) ranges.min[0] = r;
647 if (g < ranges.min[1]) ranges.min[1] = g;
648 if (b < ranges.min[2]) ranges.min[2] = b;
649
650 if (r > ranges.max[0]) ranges.max[0] = r;
651 if (g > ranges.max[1]) ranges.max[1] = g;
652 if (b > ranges.max[2]) ranges.max[2] = b;
653
654 tmp_pal[nb_color].value = c;
655 tmp_pal[nb_color].pal_id = i;
656
657 nb_color++;
658 }
659
660 if (!nb_color)
661 return -1;
662
663 /* define longest axis that will be the split component */
664 wr = ranges.max[0] - ranges.min[0];
665 wg = ranges.max[1] - ranges.min[1];
666 wb = ranges.max[2] - ranges.min[2];
667 if (wr >= wg && wr >= wb) longest = 1;
668 if (wg >= wr && wg >= wb) longest = 2;
669 if (wb >= wr && wb >= wg) longest = 3;
670 cmpf = cmp_funcs[longest];
671 *component = longest;
672
673 /* sort along this axis to get median */
674 AV_QSORT(tmp_pal, nb_color, struct color, cmpf);
675
676 return tmp_pal[nb_color >> 1].pal_id;
677 }
678
colormap_insert(struct color_node * map,uint8_t * color_used,int * nb_used,const uint32_t * palette,const int trans_thresh,const struct color_rect * box)679 static int colormap_insert(struct color_node *map,
680 uint8_t *color_used,
681 int *nb_used,
682 const uint32_t *palette,
683 const int trans_thresh,
684 const struct color_rect *box)
685 {
686 uint32_t c;
687 int component, cur_id;
688 int node_left_id = -1, node_right_id = -1;
689 struct color_node *node;
690 struct color_rect box1, box2;
691 const int pal_id = get_next_color(color_used, palette, trans_thresh, &component, box);
692
693 if (pal_id < 0)
694 return -1;
695
696 /* create new node with that color */
697 cur_id = (*nb_used)++;
698 c = palette[pal_id];
699 node = &map[cur_id];
700 node->split = component;
701 node->palette_id = pal_id;
702 node->val[0] = c>>24 & 0xff;
703 node->val[1] = c>>16 & 0xff;
704 node->val[2] = c>> 8 & 0xff;
705 node->val[3] = c & 0xff;
706
707 color_used[pal_id] = 1;
708
709 /* get the two boxes this node creates */
710 box1 = box2 = *box;
711 box1.max[component-1] = node->val[component];
712 box2.min[component-1] = node->val[component] + 1;
713
714 node_left_id = colormap_insert(map, color_used, nb_used, palette, trans_thresh, &box1);
715
716 if (box2.min[component-1] <= box2.max[component-1])
717 node_right_id = colormap_insert(map, color_used, nb_used, palette, trans_thresh, &box2);
718
719 node->left_id = node_left_id;
720 node->right_id = node_right_id;
721
722 return cur_id;
723 }
724
cmp_pal_entry(const void * a,const void * b)725 static int cmp_pal_entry(const void *a, const void *b)
726 {
727 const int c1 = *(const uint32_t *)a & 0xffffff;
728 const int c2 = *(const uint32_t *)b & 0xffffff;
729 return c1 - c2;
730 }
731
load_colormap(PaletteUseContext * s)732 static void load_colormap(PaletteUseContext *s)
733 {
734 int i, nb_used = 0;
735 uint8_t color_used[AVPALETTE_COUNT] = {0};
736 uint32_t last_color = 0;
737 struct color_rect box;
738
739 /* disable transparent colors and dups */
740 qsort(s->palette, AVPALETTE_COUNT, sizeof(*s->palette), cmp_pal_entry);
741 // update transparency index:
742 if (s->transparency_index >= 0) {
743 for (i = 0; i < AVPALETTE_COUNT; i++) {
744 if ((s->palette[i]>>24 & 0xff) == 0) {
745 s->transparency_index = i; // we are assuming at most one transparent color in palette
746 break;
747 }
748 }
749 }
750
751 for (i = 0; i < AVPALETTE_COUNT; i++) {
752 const uint32_t c = s->palette[i];
753 if (i != 0 && c == last_color) {
754 color_used[i] = 1;
755 continue;
756 }
757 last_color = c;
758 if (c >> 24 < s->trans_thresh) {
759 color_used[i] = 1; // ignore transparent color(s)
760 continue;
761 }
762 }
763
764 box.min[0] = box.min[1] = box.min[2] = 0x00;
765 box.max[0] = box.max[1] = box.max[2] = 0xff;
766
767 colormap_insert(s->map, color_used, &nb_used, s->palette, s->trans_thresh, &box);
768
769 if (s->dot_filename)
770 disp_tree(s->map, s->dot_filename);
771
772 if (s->debug_accuracy) {
773 if (!debug_accuracy(s->map, s->palette, s->trans_thresh, s->color_search_method))
774 av_log(NULL, AV_LOG_INFO, "Accuracy check passed\n");
775 }
776 }
777
debug_mean_error(PaletteUseContext * s,const AVFrame * in1,const AVFrame * in2,int frame_count)778 static void debug_mean_error(PaletteUseContext *s, const AVFrame *in1,
779 const AVFrame *in2, int frame_count)
780 {
781 int x, y;
782 const uint32_t *palette = s->palette;
783 uint32_t *src1 = (uint32_t *)in1->data[0];
784 uint8_t *src2 = in2->data[0];
785 const int src1_linesize = in1->linesize[0] >> 2;
786 const int src2_linesize = in2->linesize[0];
787 const float div = in1->width * in1->height * 3;
788 unsigned mean_err = 0;
789
790 for (y = 0; y < in1->height; y++) {
791 for (x = 0; x < in1->width; x++) {
792 const uint32_t c1 = src1[x];
793 const uint32_t c2 = palette[src2[x]];
794 const uint8_t argb1[] = {0xff, c1 >> 16 & 0xff, c1 >> 8 & 0xff, c1 & 0xff};
795 const uint8_t argb2[] = {0xff, c2 >> 16 & 0xff, c2 >> 8 & 0xff, c2 & 0xff};
796 mean_err += diff(argb1, argb2, s->trans_thresh);
797 }
798 src1 += src1_linesize;
799 src2 += src2_linesize;
800 }
801
802 s->total_mean_err += mean_err;
803
804 av_log(NULL, AV_LOG_INFO, "MEP:%.3f TotalMEP:%.3f\n",
805 mean_err / div, s->total_mean_err / (div * frame_count));
806 }
807
set_processing_window(enum diff_mode diff_mode,const AVFrame * prv_src,const AVFrame * cur_src,const AVFrame * prv_dst,AVFrame * cur_dst,int * xp,int * yp,int * wp,int * hp)808 static void set_processing_window(enum diff_mode diff_mode,
809 const AVFrame *prv_src, const AVFrame *cur_src,
810 const AVFrame *prv_dst, AVFrame *cur_dst,
811 int *xp, int *yp, int *wp, int *hp)
812 {
813 int x_start = 0, y_start = 0;
814 int width = cur_src->width;
815 int height = cur_src->height;
816
817 if (prv_src->data[0] && diff_mode == DIFF_MODE_RECTANGLE) {
818 int y;
819 int x_end = cur_src->width - 1,
820 y_end = cur_src->height - 1;
821 const uint32_t *prv_srcp = (const uint32_t *)prv_src->data[0];
822 const uint32_t *cur_srcp = (const uint32_t *)cur_src->data[0];
823 const uint8_t *prv_dstp = prv_dst->data[0];
824 uint8_t *cur_dstp = cur_dst->data[0];
825
826 const int prv_src_linesize = prv_src->linesize[0] >> 2;
827 const int cur_src_linesize = cur_src->linesize[0] >> 2;
828 const int prv_dst_linesize = prv_dst->linesize[0];
829 const int cur_dst_linesize = cur_dst->linesize[0];
830
831 /* skip common lines */
832 while (y_start < y_end && !memcmp(prv_srcp + y_start*prv_src_linesize,
833 cur_srcp + y_start*cur_src_linesize,
834 cur_src->width * 4)) {
835 memcpy(cur_dstp + y_start*cur_dst_linesize,
836 prv_dstp + y_start*prv_dst_linesize,
837 cur_dst->width);
838 y_start++;
839 }
840 while (y_end > y_start && !memcmp(prv_srcp + y_end*prv_src_linesize,
841 cur_srcp + y_end*cur_src_linesize,
842 cur_src->width * 4)) {
843 memcpy(cur_dstp + y_end*cur_dst_linesize,
844 prv_dstp + y_end*prv_dst_linesize,
845 cur_dst->width);
846 y_end--;
847 }
848
849 height = y_end + 1 - y_start;
850
851 /* skip common columns */
852 while (x_start < x_end) {
853 int same_column = 1;
854 for (y = y_start; y <= y_end; y++) {
855 if (prv_srcp[y*prv_src_linesize + x_start] != cur_srcp[y*cur_src_linesize + x_start]) {
856 same_column = 0;
857 break;
858 }
859 }
860 if (!same_column)
861 break;
862 x_start++;
863 }
864 while (x_end > x_start) {
865 int same_column = 1;
866 for (y = y_start; y <= y_end; y++) {
867 if (prv_srcp[y*prv_src_linesize + x_end] != cur_srcp[y*cur_src_linesize + x_end]) {
868 same_column = 0;
869 break;
870 }
871 }
872 if (!same_column)
873 break;
874 x_end--;
875 }
876 width = x_end + 1 - x_start;
877
878 if (x_start) {
879 for (y = y_start; y <= y_end; y++)
880 memcpy(cur_dstp + y*cur_dst_linesize,
881 prv_dstp + y*prv_dst_linesize, x_start);
882 }
883 if (x_end != cur_src->width - 1) {
884 const int copy_len = cur_src->width - 1 - x_end;
885 for (y = y_start; y <= y_end; y++)
886 memcpy(cur_dstp + y*cur_dst_linesize + x_end + 1,
887 prv_dstp + y*prv_dst_linesize + x_end + 1,
888 copy_len);
889 }
890 }
891 *xp = x_start;
892 *yp = y_start;
893 *wp = width;
894 *hp = height;
895 }
896
apply_palette(AVFilterLink * inlink,AVFrame * in,AVFrame ** outf)897 static int apply_palette(AVFilterLink *inlink, AVFrame *in, AVFrame **outf)
898 {
899 int x, y, w, h, ret;
900 AVFilterContext *ctx = inlink->dst;
901 PaletteUseContext *s = ctx->priv;
902 AVFilterLink *outlink = inlink->dst->outputs[0];
903
904 AVFrame *out = ff_get_video_buffer(outlink, outlink->w, outlink->h);
905 if (!out) {
906 *outf = NULL;
907 return AVERROR(ENOMEM);
908 }
909 av_frame_copy_props(out, in);
910
911 set_processing_window(s->diff_mode, s->last_in, in,
912 s->last_out, out, &x, &y, &w, &h);
913 av_frame_unref(s->last_in);
914 av_frame_unref(s->last_out);
915 if ((ret = av_frame_ref(s->last_in, in)) < 0 ||
916 (ret = av_frame_ref(s->last_out, out)) < 0 ||
917 (ret = av_frame_make_writable(s->last_in)) < 0) {
918 av_frame_free(&out);
919 *outf = NULL;
920 return ret;
921 }
922
923 ff_dlog(ctx, "%dx%d rect: (%d;%d) -> (%d,%d) [area:%dx%d]\n",
924 w, h, x, y, x+w, y+h, in->width, in->height);
925
926 ret = s->set_frame(s, out, in, x, y, w, h);
927 if (ret < 0) {
928 av_frame_free(&out);
929 *outf = NULL;
930 return ret;
931 }
932 memcpy(out->data[1], s->palette, AVPALETTE_SIZE);
933 if (s->calc_mean_err)
934 debug_mean_error(s, in, out, inlink->frame_count_out);
935 *outf = out;
936 return 0;
937 }
938
config_output(AVFilterLink * outlink)939 static int config_output(AVFilterLink *outlink)
940 {
941 int ret;
942 AVFilterContext *ctx = outlink->src;
943 PaletteUseContext *s = ctx->priv;
944
945 ret = ff_framesync_init_dualinput(&s->fs, ctx);
946 if (ret < 0)
947 return ret;
948 s->fs.opt_repeatlast = 1; // only 1 frame in the palette
949 s->fs.in[1].before = s->fs.in[1].after = EXT_INFINITY;
950 s->fs.on_event = load_apply_palette;
951
952 outlink->w = ctx->inputs[0]->w;
953 outlink->h = ctx->inputs[0]->h;
954
955 outlink->time_base = ctx->inputs[0]->time_base;
956 if ((ret = ff_framesync_configure(&s->fs)) < 0)
957 return ret;
958 return 0;
959 }
960
config_input_palette(AVFilterLink * inlink)961 static int config_input_palette(AVFilterLink *inlink)
962 {
963 AVFilterContext *ctx = inlink->dst;
964
965 if (inlink->w * inlink->h != AVPALETTE_COUNT) {
966 av_log(ctx, AV_LOG_ERROR,
967 "Palette input must contain exactly %d pixels. "
968 "Specified input has %dx%d=%d pixels\n",
969 AVPALETTE_COUNT, inlink->w, inlink->h,
970 inlink->w * inlink->h);
971 return AVERROR(EINVAL);
972 }
973 return 0;
974 }
975
load_palette(PaletteUseContext * s,const AVFrame * palette_frame)976 static void load_palette(PaletteUseContext *s, const AVFrame *palette_frame)
977 {
978 int i, x, y;
979 const uint32_t *p = (const uint32_t *)palette_frame->data[0];
980 const int p_linesize = palette_frame->linesize[0] >> 2;
981
982 s->transparency_index = -1;
983
984 if (s->new) {
985 memset(s->palette, 0, sizeof(s->palette));
986 memset(s->map, 0, sizeof(s->map));
987 for (i = 0; i < CACHE_SIZE; i++)
988 av_freep(&s->cache[i].entries);
989 memset(s->cache, 0, sizeof(s->cache));
990 }
991
992 i = 0;
993 for (y = 0; y < palette_frame->height; y++) {
994 for (x = 0; x < palette_frame->width; x++) {
995 s->palette[i] = p[x];
996 if (p[x]>>24 < s->trans_thresh) {
997 s->transparency_index = i; // we are assuming at most one transparent color in palette
998 }
999 i++;
1000 }
1001 p += p_linesize;
1002 }
1003
1004 load_colormap(s);
1005
1006 if (!s->new)
1007 s->palette_loaded = 1;
1008 }
1009
load_apply_palette(FFFrameSync * fs)1010 static int load_apply_palette(FFFrameSync *fs)
1011 {
1012 AVFilterContext *ctx = fs->parent;
1013 AVFilterLink *inlink = ctx->inputs[0];
1014 PaletteUseContext *s = ctx->priv;
1015 AVFrame *master, *second, *out = NULL;
1016 int ret;
1017
1018 // writable for error diffusal dithering
1019 ret = ff_framesync_dualinput_get_writable(fs, &master, &second);
1020 if (ret < 0)
1021 return ret;
1022 if (!master || !second) {
1023 av_frame_free(&master);
1024 return AVERROR_BUG;
1025 }
1026 if (!s->palette_loaded) {
1027 load_palette(s, second);
1028 }
1029 ret = apply_palette(inlink, master, &out);
1030 av_frame_free(&master);
1031 if (ret < 0)
1032 return ret;
1033 return ff_filter_frame(ctx->outputs[0], out);
1034 }
1035
1036 #define DEFINE_SET_FRAME(color_search, name, value) \
1037 static int set_frame_##name(PaletteUseContext *s, AVFrame *out, AVFrame *in, \
1038 int x_start, int y_start, int w, int h) \
1039 { \
1040 return set_frame(s, out, in, x_start, y_start, w, h, value, color_search); \
1041 }
1042
1043 #define DEFINE_SET_FRAME_COLOR_SEARCH(color_search, color_search_macro) \
1044 DEFINE_SET_FRAME(color_search_macro, color_search##_##none, DITHERING_NONE) \
1045 DEFINE_SET_FRAME(color_search_macro, color_search##_##bayer, DITHERING_BAYER) \
1046 DEFINE_SET_FRAME(color_search_macro, color_search##_##heckbert, DITHERING_HECKBERT) \
1047 DEFINE_SET_FRAME(color_search_macro, color_search##_##floyd_steinberg, DITHERING_FLOYD_STEINBERG) \
1048 DEFINE_SET_FRAME(color_search_macro, color_search##_##sierra2, DITHERING_SIERRA2) \
1049 DEFINE_SET_FRAME(color_search_macro, color_search##_##sierra2_4a, DITHERING_SIERRA2_4A) \
1050
1051 DEFINE_SET_FRAME_COLOR_SEARCH(nns_iterative, COLOR_SEARCH_NNS_ITERATIVE)
1052 DEFINE_SET_FRAME_COLOR_SEARCH(nns_recursive, COLOR_SEARCH_NNS_RECURSIVE)
1053 DEFINE_SET_FRAME_COLOR_SEARCH(bruteforce, COLOR_SEARCH_BRUTEFORCE)
1054
1055 #define DITHERING_ENTRIES(color_search) { \
1056 set_frame_##color_search##_none, \
1057 set_frame_##color_search##_bayer, \
1058 set_frame_##color_search##_heckbert, \
1059 set_frame_##color_search##_floyd_steinberg, \
1060 set_frame_##color_search##_sierra2, \
1061 set_frame_##color_search##_sierra2_4a, \
1062 }
1063
1064 static const set_frame_func set_frame_lut[NB_COLOR_SEARCHES][NB_DITHERING] = {
1065 DITHERING_ENTRIES(nns_iterative),
1066 DITHERING_ENTRIES(nns_recursive),
1067 DITHERING_ENTRIES(bruteforce),
1068 };
1069
dither_value(int p)1070 static int dither_value(int p)
1071 {
1072 const int q = p ^ (p >> 3);
1073 return (p & 4) >> 2 | (q & 4) >> 1 \
1074 | (p & 2) << 1 | (q & 2) << 2 \
1075 | (p & 1) << 4 | (q & 1) << 5;
1076 }
1077
init(AVFilterContext * ctx)1078 static av_cold int init(AVFilterContext *ctx)
1079 {
1080 PaletteUseContext *s = ctx->priv;
1081
1082 s->last_in = av_frame_alloc();
1083 s->last_out = av_frame_alloc();
1084 if (!s->last_in || !s->last_out) {
1085 av_frame_free(&s->last_in);
1086 av_frame_free(&s->last_out);
1087 return AVERROR(ENOMEM);
1088 }
1089
1090 s->set_frame = set_frame_lut[s->color_search_method][s->dither];
1091
1092 if (s->dither == DITHERING_BAYER) {
1093 int i;
1094 const int delta = 1 << (5 - s->bayer_scale); // to avoid too much luma
1095
1096 for (i = 0; i < FF_ARRAY_ELEMS(s->ordered_dither); i++)
1097 s->ordered_dither[i] = (dither_value(i) >> s->bayer_scale) - delta;
1098 }
1099
1100 return 0;
1101 }
1102
activate(AVFilterContext * ctx)1103 static int activate(AVFilterContext *ctx)
1104 {
1105 PaletteUseContext *s = ctx->priv;
1106 return ff_framesync_activate(&s->fs);
1107 }
1108
uninit(AVFilterContext * ctx)1109 static av_cold void uninit(AVFilterContext *ctx)
1110 {
1111 int i;
1112 PaletteUseContext *s = ctx->priv;
1113
1114 ff_framesync_uninit(&s->fs);
1115 for (i = 0; i < CACHE_SIZE; i++)
1116 av_freep(&s->cache[i].entries);
1117 av_frame_free(&s->last_in);
1118 av_frame_free(&s->last_out);
1119 }
1120
1121 static const AVFilterPad paletteuse_inputs[] = {
1122 {
1123 .name = "default",
1124 .type = AVMEDIA_TYPE_VIDEO,
1125 },{
1126 .name = "palette",
1127 .type = AVMEDIA_TYPE_VIDEO,
1128 .config_props = config_input_palette,
1129 },
1130 { NULL }
1131 };
1132
1133 static const AVFilterPad paletteuse_outputs[] = {
1134 {
1135 .name = "default",
1136 .type = AVMEDIA_TYPE_VIDEO,
1137 .config_props = config_output,
1138 },
1139 { NULL }
1140 };
1141
1142 AVFilter ff_vf_paletteuse = {
1143 .name = "paletteuse",
1144 .description = NULL_IF_CONFIG_SMALL("Use a palette to downsample an input video stream."),
1145 .priv_size = sizeof(PaletteUseContext),
1146 .query_formats = query_formats,
1147 .init = init,
1148 .uninit = uninit,
1149 .activate = activate,
1150 .inputs = paletteuse_inputs,
1151 .outputs = paletteuse_outputs,
1152 .priv_class = &paletteuse_class,
1153 };
1154