2 * This file is part of FFmpeg.
4 * FFmpeg is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU Lesser General Public
6 * License as published by the Free Software Foundation; either
7 * version 2.1 of the License, or (at your option) any later version.
9 * FFmpeg is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12 * Lesser General Public License for more details.
14 * You should have received a copy of the GNU Lesser General Public
15 * License along with FFmpeg; if not, write to the Free Software
16 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
21 * Use a palette to downsample an input video stream.
24 #include "libavutil/bprint.h"
25 #include "libavutil/opt.h"
26 #include "dualinput.h"
33 DITHERING_FLOYD_STEINBERG,
39 enum color_search_method {
40 COLOR_SEARCH_NNS_ITERATIVE,
41 COLOR_SEARCH_NNS_RECURSIVE,
42 COLOR_SEARCH_BRUTEFORCE,
50 int left_id, right_id;
54 #define CACHE_SIZE (1<<(3*NBITS))
62 struct cached_color *entries;
66 struct PaletteUseContext;
68 typedef int (*set_frame_func)(struct PaletteUseContext *s, AVFrame *out, AVFrame *in);
70 typedef struct PaletteUseContext {
72 FFDualInputContext dinput;
73 struct cache_node cache[CACHE_SIZE]; /* lookup cache */
74 struct color_node map[AVPALETTE_COUNT]; /* 3D-Tree (KD-Tree with K=3) for reverse colormap */
75 uint32_t palette[AVPALETTE_COUNT];
78 set_frame_func set_frame;
80 int ordered_dither[8*8];
84 int color_search_method;
86 uint64_t total_mean_err;
90 #define OFFSET(x) offsetof(PaletteUseContext, x)
91 #define FLAGS AV_OPT_FLAG_FILTERING_PARAM|AV_OPT_FLAG_VIDEO_PARAM
92 static const AVOption paletteuse_options[] = {
93 { "dither", "select dithering mode", OFFSET(dither), AV_OPT_TYPE_INT, {.i64=DITHERING_SIERRA2_4A}, 0, NB_DITHERING-1, FLAGS, "dithering_mode" },
94 { "bayer", "ordered 8x8 bayer dithering (deterministic)", 0, AV_OPT_TYPE_CONST, {.i64=DITHERING_BAYER}, INT_MIN, INT_MAX, FLAGS, "dithering_mode" },
95 { "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" },
96 { "floyd_steinberg", "Floyd and Steingberg dithering (error diffusion)", 0, AV_OPT_TYPE_CONST, {.i64=DITHERING_FLOYD_STEINBERG}, INT_MIN, INT_MAX, FLAGS, "dithering_mode" },
97 { "sierra2", "Frankie Sierra dithering v2 (error diffusion)", 0, AV_OPT_TYPE_CONST, {.i64=DITHERING_SIERRA2}, INT_MIN, INT_MAX, FLAGS, "dithering_mode" },
98 { "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" },
99 { "bayer_scale", "set scale for bayer dithering", OFFSET(bayer_scale), AV_OPT_TYPE_INT, {.i64=2}, 0, 5, FLAGS },
101 /* following are the debug options, not part of the official API */
102 { "debug_kdtree", "save Graphviz graph of the kdtree in specified file", OFFSET(dot_filename), AV_OPT_TYPE_STRING, {.str=NULL}, CHAR_MIN, CHAR_MAX, FLAGS },
103 { "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" },
104 { "nns_iterative", "iterative search", 0, AV_OPT_TYPE_CONST, {.i64=COLOR_SEARCH_NNS_ITERATIVE}, INT_MIN, INT_MAX, FLAGS, "search" },
105 { "nns_recursive", "recursive search", 0, AV_OPT_TYPE_CONST, {.i64=COLOR_SEARCH_NNS_RECURSIVE}, INT_MIN, INT_MAX, FLAGS, "search" },
106 { "bruteforce", "brute-force into the palette", 0, AV_OPT_TYPE_CONST, {.i64=COLOR_SEARCH_BRUTEFORCE}, INT_MIN, INT_MAX, FLAGS, "search" },
107 { "mean_err", "compute and print mean error", OFFSET(calc_mean_err), AV_OPT_TYPE_INT, {.i64=0}, 0, 1, FLAGS },
108 { "debug_accuracy", "test color search accuracy", OFFSET(debug_accuracy), AV_OPT_TYPE_FLAGS, {.i64=0}, 0, 1, FLAGS },
112 AVFILTER_DEFINE_CLASS(paletteuse);
114 static int query_formats(AVFilterContext *ctx)
116 static const enum AVPixelFormat in_fmts[] = {AV_PIX_FMT_RGB32, AV_PIX_FMT_NONE};
117 static const enum AVPixelFormat inpal_fmts[] = {AV_PIX_FMT_RGB32, AV_PIX_FMT_NONE};
118 static const enum AVPixelFormat out_fmts[] = {AV_PIX_FMT_PAL8, AV_PIX_FMT_NONE};
119 AVFilterFormats *in = ff_make_format_list(in_fmts);
120 AVFilterFormats *inpal = ff_make_format_list(inpal_fmts);
121 AVFilterFormats *out = ff_make_format_list(out_fmts);
122 if (!in || !inpal || !out) {
126 return AVERROR(ENOMEM);
128 ff_formats_ref(in, &ctx->inputs[0]->out_formats);
129 ff_formats_ref(inpal, &ctx->inputs[1]->out_formats);
130 ff_formats_ref(out, &ctx->outputs[0]->in_formats);
134 static av_always_inline int dither_color(uint32_t px, int er, int eg, int eb, int scale, int shift)
136 return av_clip_uint8((px >> 16 & 0xff) + ((er * scale) >> shift)) << 16
137 | av_clip_uint8((px >> 8 & 0xff) + ((eg * scale) >> shift)) << 8
138 | av_clip_uint8((px & 0xff) + ((eb * scale) >> shift));
141 static av_always_inline int diff(const uint8_t *c1, const uint8_t *c2)
143 // XXX: try L*a*b with CIE76 (dL*dL + da*da + db*db)
144 const int dr = c1[0] - c2[0];
145 const int dg = c1[1] - c2[1];
146 const int db = c1[2] - c2[2];
147 return dr*dr + dg*dg + db*db;
150 static av_always_inline uint8_t colormap_nearest_bruteforce(const uint32_t *palette, const uint8_t *rgb)
152 int i, pal_id = -1, min_dist = INT_MAX;
154 for (i = 0; i < AVPALETTE_COUNT; i++) {
155 const uint32_t c = palette[i];
157 if ((c & 0xff000000) == 0xff000000) { // ignore transparent entry
158 const uint8_t palrgb[] = {
159 palette[i]>>16 & 0xff,
160 palette[i]>> 8 & 0xff,
163 const int d = diff(palrgb, rgb);
173 /* Recursive form, simpler but a bit slower. Kept for reference. */
174 struct nearest_color {
179 static void colormap_nearest_node(const struct color_node *map,
181 const uint8_t *target,
182 struct nearest_color *nearest)
184 const struct color_node *kd = map + node_pos;
185 const int s = kd->split;
186 int dx, nearer_kd_id, further_kd_id;
187 const uint8_t *current = kd->val;
188 const int current_to_target = diff(target, current);
190 if (current_to_target < nearest->dist_sqd) {
191 nearest->node_pos = node_pos;
192 nearest->dist_sqd = current_to_target;
195 if (kd->left_id != -1 || kd->right_id != -1) {
196 dx = target[s] - current[s];
198 if (dx <= 0) nearer_kd_id = kd->left_id, further_kd_id = kd->right_id;
199 else nearer_kd_id = kd->right_id, further_kd_id = kd->left_id;
201 if (nearer_kd_id != -1)
202 colormap_nearest_node(map, nearer_kd_id, target, nearest);
204 if (further_kd_id != -1 && dx*dx < nearest->dist_sqd)
205 colormap_nearest_node(map, further_kd_id, target, nearest);
209 static av_always_inline uint8_t colormap_nearest_recursive(const struct color_node *node, const uint8_t *rgb)
211 struct nearest_color res = {.dist_sqd = INT_MAX, .node_pos = -1};
212 colormap_nearest_node(node, 0, rgb, &res);
213 return node[res.node_pos].palette_id;
221 static av_always_inline uint8_t colormap_nearest_iterative(const struct color_node *root, const uint8_t *target)
223 int pos = 0, best_node_id = -1, best_dist = INT_MAX, cur_color_id = 0;
224 struct stack_node nodes[16];
225 struct stack_node *node = &nodes[0];
229 const struct color_node *kd = &root[cur_color_id];
230 const uint8_t *current = kd->val;
231 const int current_to_target = diff(target, current);
233 /* Compare current color node to the target and update our best node if
234 * it's actually better. */
235 if (current_to_target < best_dist) {
236 best_node_id = cur_color_id;
237 if (!current_to_target)
238 goto end; // exact match, we can return immediately
239 best_dist = current_to_target;
242 /* Check if it's not a leaf */
243 if (kd->left_id != -1 || kd->right_id != -1) {
244 const int split = kd->split;
245 const int dx = target[split] - current[split];
246 int nearer_kd_id, further_kd_id;
248 /* Define which side is the most interesting. */
249 if (dx <= 0) nearer_kd_id = kd->left_id, further_kd_id = kd->right_id;
250 else nearer_kd_id = kd->right_id, further_kd_id = kd->left_id;
252 if (nearer_kd_id != -1) {
253 if (further_kd_id != -1) {
254 /* Here, both paths are defined, so we push a state for
255 * when we are going back. */
256 node->color_id = further_kd_id;
261 /* We can now update current color with the most probable path
262 * (no need to create a state since there is nothing to save
264 cur_color_id = nearer_kd_id;
266 } else if (dx*dx < best_dist) {
267 /* The nearest path isn't available, so there is only one path
268 * possible and it's the least probable. We enter it only if the
269 * distance from the current point to the hyper rectangle is
270 * less than our best distance. */
271 cur_color_id = further_kd_id;
276 /* Unstack as much as we can, typically as long as the least probable
277 * branch aren't actually probable. */
282 } while (node->dx2 >= best_dist);
284 /* We got a node where the least probable branch might actually contain
285 * a relevant color. */
286 cur_color_id = node->color_id;
290 return root[best_node_id].palette_id;
293 #define COLORMAP_NEAREST(search, palette, root, target) \
294 search == COLOR_SEARCH_NNS_ITERATIVE ? colormap_nearest_iterative(root, target) : \
295 search == COLOR_SEARCH_NNS_RECURSIVE ? colormap_nearest_recursive(root, target) : \
296 colormap_nearest_bruteforce(palette, target)
299 * Check if the requested color is in the cache already. If not, find it in the
300 * color tree and cache it.
301 * Note: r, g, and b are the component of c but are passed as well to avoid
302 * recomputing them (they are generally computed by the caller for other uses).
304 static av_always_inline uint8_t color_get(struct cache_node *cache, uint32_t color,
305 uint8_t r, uint8_t g, uint8_t b,
306 const struct color_node *map,
307 const uint32_t *palette,
308 const enum color_search_method search_method)
311 const uint8_t rgb[] = {r, g, b};
312 const uint8_t rhash = r & ((1<<NBITS)-1);
313 const uint8_t ghash = g & ((1<<NBITS)-1);
314 const uint8_t bhash = b & ((1<<NBITS)-1);
315 const unsigned hash = rhash<<(NBITS*2) | ghash<<NBITS | bhash;
316 struct cache_node *node = &cache[hash];
317 struct cached_color *e;
319 for (i = 0; i < node->nb_entries; i++) {
320 e = &node->entries[i];
321 if (e->color == color)
325 e = av_dynarray2_add((void**)&node->entries, &node->nb_entries,
326 sizeof(*node->entries), NULL);
328 return AVERROR(ENOMEM);
330 e->pal_entry = COLORMAP_NEAREST(search_method, palette, map, rgb);
334 static av_always_inline uint8_t get_dst_color_err(struct cache_node *cache,
335 uint32_t c, const struct color_node *map,
336 const uint32_t *palette,
337 int *er, int *eg, int *eb,
338 const enum color_search_method search_method)
340 const uint8_t r = c >> 16 & 0xff;
341 const uint8_t g = c >> 8 & 0xff;
342 const uint8_t b = c & 0xff;
343 const uint8_t dstx = color_get(cache, c, r, g, b, map, palette, search_method);
344 const uint32_t dstc = palette[dstx];
345 *er = r - (dstc >> 16 & 0xff);
346 *eg = g - (dstc >> 8 & 0xff);
347 *eb = b - (dstc & 0xff);
351 static av_always_inline int set_frame(PaletteUseContext *s, AVFrame *out, AVFrame *in,
352 enum dithering_mode dither,
353 const enum color_search_method search_method)
356 const struct color_node *map = s->map;
357 struct cache_node *cache = s->cache;
358 const uint32_t *palette = s->palette;
359 uint32_t *src = (uint32_t *)in ->data[0];
360 uint8_t *dst = out->data[0];
361 const int src_linesize = in ->linesize[0] >> 2;
362 const int dst_linesize = out->linesize[0];
364 for (y = 0; y < in->height; y++) {
365 for (x = 0; x < in->width; x++) {
368 if (dither == DITHERING_BAYER) {
369 const int d = s->ordered_dither[(y & 7)<<3 | (x & 7)];
370 const uint8_t r8 = src[x] >> 16 & 0xff;
371 const uint8_t g8 = src[x] >> 8 & 0xff;
372 const uint8_t b8 = src[x] & 0xff;
373 const uint8_t r = av_clip_uint8(r8 + d);
374 const uint8_t g = av_clip_uint8(g8 + d);
375 const uint8_t b = av_clip_uint8(b8 + d);
376 const uint32_t c = r<<16 | g<<8 | b;
377 const int color = color_get(cache, c, r, g, b, map, palette, search_method);
383 } else if (dither == DITHERING_HECKBERT) {
384 const int right = x < in->width - 1, down = y < in->height - 1;
385 const int color = get_dst_color_err(cache, src[x], map, palette, &er, &eg, &eb, search_method);
391 if (right) src[ x + 1] = dither_color(src[ x + 1], er, eg, eb, 3, 3);
392 if ( down) src[src_linesize + x ] = dither_color(src[src_linesize + x ], er, eg, eb, 3, 3);
393 if (right && down) src[src_linesize + x + 1] = dither_color(src[src_linesize + x + 1], er, eg, eb, 2, 3);
395 } else if (dither == DITHERING_FLOYD_STEINBERG) {
396 const int right = x < in->width - 1, down = y < in->height - 1, left = x > 0;
397 const int color = get_dst_color_err(cache, src[x], map, palette, &er, &eg, &eb, search_method);
403 if (right) src[ x + 1] = dither_color(src[ x + 1], er, eg, eb, 7, 4);
404 if (left && down) src[src_linesize + x - 1] = dither_color(src[src_linesize + x - 1], er, eg, eb, 3, 4);
405 if ( down) src[src_linesize + x ] = dither_color(src[src_linesize + x ], er, eg, eb, 5, 4);
406 if (right && down) src[src_linesize + x + 1] = dither_color(src[src_linesize + x + 1], er, eg, eb, 1, 4);
408 } else if (dither == DITHERING_SIERRA2) {
409 const int right = x < in->width - 1, down = y < in->height - 1, left = x > 0;
410 const int right2 = x < in->width - 2, left2 = x > 1;
411 const int color = get_dst_color_err(cache, src[x], map, palette, &er, &eg, &eb, search_method);
417 if (right) src[ x + 1] = dither_color(src[ x + 1], er, eg, eb, 4, 4);
418 if (right2) src[ x + 2] = dither_color(src[ x + 2], er, eg, eb, 3, 4);
421 if (left2) src[ src_linesize + x - 2] = dither_color(src[ src_linesize + x - 2], er, eg, eb, 1, 4);
422 if (left) src[ src_linesize + x - 1] = dither_color(src[ src_linesize + x - 1], er, eg, eb, 2, 4);
423 src[ src_linesize + x ] = dither_color(src[ src_linesize + x ], er, eg, eb, 3, 4);
424 if (right) src[ src_linesize + x + 1] = dither_color(src[ src_linesize + x + 1], er, eg, eb, 2, 4);
425 if (right2) src[ src_linesize + x + 2] = dither_color(src[ src_linesize + x + 2], er, eg, eb, 1, 4);
428 } else if (dither == DITHERING_SIERRA2_4A) {
429 const int right = x < in->width - 1, down = y < in->height - 1, left = x > 0;
430 const int color = get_dst_color_err(cache, src[x], map, palette, &er, &eg, &eb, search_method);
436 if (right) src[ x + 1] = dither_color(src[ x + 1], er, eg, eb, 2, 2);
437 if (left && down) src[src_linesize + x - 1] = dither_color(src[src_linesize + x - 1], er, eg, eb, 1, 2);
438 if ( down) src[src_linesize + x ] = dither_color(src[src_linesize + x ], er, eg, eb, 1, 2);
441 const uint8_t r = src[x] >> 16 & 0xff;
442 const uint8_t g = src[x] >> 8 & 0xff;
443 const uint8_t b = src[x] & 0xff;
444 const int color = color_get(cache, src[x] & 0xffffff, r, g, b, map, palette, search_method);
458 static void disp_node(AVBPrint *buf,
459 const struct color_node *map,
460 int parent_id, int node_id,
463 const struct color_node *node = &map[node_id];
464 const uint32_t fontcolor = node->val[0] > 0x50 &&
465 node->val[1] > 0x50 &&
466 node->val[2] > 0x50 ? 0 : 0xffffff;
467 av_bprintf(buf, "%*cnode%d ["
468 "label=\"%c%02X%c%02X%c%02X%c\" "
469 "fillcolor=\"#%02x%02x%02x\" "
470 "fontcolor=\"#%06X\"]\n",
471 depth*INDENT, ' ', node->palette_id,
472 "[ "[node->split], node->val[0],
473 "][ "[node->split], node->val[1],
474 " ]["[node->split], node->val[2],
476 node->val[0], node->val[1], node->val[2],
479 av_bprintf(buf, "%*cnode%d -> node%d\n", depth*INDENT, ' ',
480 map[parent_id].palette_id, node->palette_id);
481 if (node->left_id != -1) disp_node(buf, map, node_id, node->left_id, depth + 1);
482 if (node->right_id != -1) disp_node(buf, map, node_id, node->right_id, depth + 1);
485 // debug_kdtree=kdtree.dot -> dot -Tpng kdtree.dot > kdtree.png
486 static int disp_tree(const struct color_node *node, const char *fname)
489 FILE *f = av_fopen_utf8(fname, "w");
492 int ret = AVERROR(errno);
493 av_log(NULL, AV_LOG_ERROR, "Cannot open file '%s' for writing: %s\n",
494 fname, av_err2str(ret));
498 av_bprint_init(&buf, 0, AV_BPRINT_SIZE_UNLIMITED);
500 av_bprintf(&buf, "digraph {\n");
501 av_bprintf(&buf, " node [style=filled fontsize=10 shape=box]\n");
502 disp_node(&buf, node, -1, 0, 0);
503 av_bprintf(&buf, "}\n");
505 fwrite(buf.str, 1, buf.len, f);
507 av_bprint_finalize(&buf, NULL);
511 static int debug_accuracy(const struct color_node *node, const uint32_t *palette,
512 const enum color_search_method search_method)
514 int r, g, b, ret = 0;
516 for (r = 0; r < 256; r++) {
517 for (g = 0; g < 256; g++) {
518 for (b = 0; b < 256; b++) {
519 const uint8_t rgb[] = {r, g, b};
520 const int r1 = COLORMAP_NEAREST(search_method, palette, node, rgb);
521 const int r2 = colormap_nearest_bruteforce(palette, rgb);
523 const uint32_t c1 = palette[r1];
524 const uint32_t c2 = palette[r2];
525 const uint8_t palrgb1[] = { c1>>16 & 0xff, c1>> 8 & 0xff, c1 & 0xff };
526 const uint8_t palrgb2[] = { c2>>16 & 0xff, c2>> 8 & 0xff, c2 & 0xff };
527 const int d1 = diff(palrgb1, rgb);
528 const int d2 = diff(palrgb2, rgb);
530 av_log(NULL, AV_LOG_ERROR,
531 "/!\\ %02X%02X%02X: %d ! %d (%06X ! %06X) / dist: %d ! %d\n",
532 r, g, b, r1, r2, c1 & 0xffffff, c2 & 0xffffff, d1, d2);
552 typedef int (*cmp_func)(const void *, const void *);
554 #define DECLARE_CMP_FUNC(name, pos) \
555 static int cmp_##name(const void *pa, const void *pb) \
557 const struct color *a = pa; \
558 const struct color *b = pb; \
559 return (a->value >> (8 * (2 - (pos))) & 0xff) \
560 - (b->value >> (8 * (2 - (pos))) & 0xff); \
563 DECLARE_CMP_FUNC(r, 0)
564 DECLARE_CMP_FUNC(g, 1)
565 DECLARE_CMP_FUNC(b, 2)
567 static const cmp_func cmp_funcs[] = {cmp_r, cmp_g, cmp_b};
569 static int get_next_color(const uint8_t *color_used, const uint32_t *palette,
570 int *component, const struct color_rect *box)
574 unsigned nb_color = 0;
575 struct color_rect ranges;
576 struct color tmp_pal[256];
578 ranges.min[0] = ranges.min[1] = ranges.min[2] = 0xff;
579 ranges.max[0] = ranges.max[1] = ranges.max[2] = 0x00;
581 for (i = 0; i < AVPALETTE_COUNT; i++) {
582 const uint32_t c = palette[i];
583 const uint8_t r = c >> 16 & 0xff;
584 const uint8_t g = c >> 8 & 0xff;
585 const uint8_t b = c & 0xff;
588 r < box->min[0] || g < box->min[1] || b < box->min[2] ||
589 r > box->max[0] || g > box->max[1] || b > box->max[2])
592 if (r < ranges.min[0]) ranges.min[0] = r;
593 if (g < ranges.min[1]) ranges.min[1] = g;
594 if (b < ranges.min[2]) ranges.min[2] = b;
596 if (r > ranges.max[0]) ranges.max[0] = r;
597 if (g > ranges.max[1]) ranges.max[1] = g;
598 if (b > ranges.max[2]) ranges.max[2] = b;
600 tmp_pal[nb_color].value = c;
601 tmp_pal[nb_color].pal_id = i;
609 /* define longest axis that will be the split component */
610 wr = ranges.max[0] - ranges.min[0];
611 wg = ranges.max[1] - ranges.min[1];
612 wb = ranges.max[2] - ranges.min[2];
613 if (wr >= wg && wr >= wb) longest = 0;
614 if (wg >= wr && wg >= wb) longest = 1;
615 if (wb >= wr && wb >= wg) longest = 2;
616 *component = longest;
618 /* sort along this axis to get median */
619 qsort(tmp_pal, nb_color, sizeof(*tmp_pal), cmp_funcs[longest]);
621 return tmp_pal[nb_color >> 1].pal_id;
624 static int colormap_insert(struct color_node *map,
627 const uint32_t *palette,
628 const struct color_rect *box)
631 int component, cur_id;
632 int node_left_id = -1, node_right_id = -1;
633 struct color_node *node;
634 struct color_rect box1, box2;
635 const int pal_id = get_next_color(color_used, palette, &component, box);
640 /* create new node with that color */
641 cur_id = (*nb_used)++;
644 node->split = component;
645 node->palette_id = pal_id;
646 node->val[0] = c>>16 & 0xff;
647 node->val[1] = c>> 8 & 0xff;
648 node->val[2] = c & 0xff;
650 color_used[pal_id] = 1;
652 /* get the two boxes this node creates */
654 box1.max[component] = node->val[component];
655 box2.min[component] = node->val[component] + 1;
657 node_left_id = colormap_insert(map, color_used, nb_used, palette, &box1);
659 if (box2.min[component] <= box2.max[component])
660 node_right_id = colormap_insert(map, color_used, nb_used, palette, &box2);
662 node->left_id = node_left_id;
663 node->right_id = node_right_id;
668 static int cmp_pal_entry(const void *a, const void *b)
670 const int c1 = *(const uint32_t *)a & 0xffffff;
671 const int c2 = *(const uint32_t *)b & 0xffffff;
675 static void load_colormap(PaletteUseContext *s)
678 uint8_t color_used[AVPALETTE_COUNT] = {0};
679 uint32_t last_color = 0;
680 struct color_rect box;
682 /* disable transparent colors and dups */
683 qsort(s->palette, AVPALETTE_COUNT, sizeof(*s->palette), cmp_pal_entry);
684 for (i = 0; i < AVPALETTE_COUNT; i++) {
685 const uint32_t c = s->palette[i];
686 if (i != 0 && c == last_color) {
691 if ((c & 0xff000000) != 0xff000000) {
692 color_used[i] = 1; // ignore transparent color(s)
697 box.min[0] = box.min[1] = box.min[2] = 0x00;
698 box.max[0] = box.max[1] = box.max[2] = 0xff;
700 colormap_insert(s->map, color_used, &nb_used, s->palette, &box);
703 disp_tree(s->map, s->dot_filename);
705 if (s->debug_accuracy) {
706 if (!debug_accuracy(s->map, s->palette, s->color_search_method))
707 av_log(NULL, AV_LOG_INFO, "Accuracy check passed\n");
711 static void debug_mean_error(PaletteUseContext *s, const AVFrame *in1,
712 const AVFrame *in2, int frame_count)
715 const uint32_t *palette = s->palette;
716 uint32_t *src1 = (uint32_t *)in1->data[0];
717 uint8_t *src2 = in2->data[0];
718 const int src1_linesize = in1->linesize[0] >> 2;
719 const int src2_linesize = in2->linesize[0];
720 const float div = in1->width * in1->height * 3;
721 unsigned mean_err = 0;
723 for (y = 0; y < in1->height; y++) {
724 for (x = 0; x < in1->width; x++) {
725 const uint32_t c1 = src1[x];
726 const uint32_t c2 = palette[src2[x]];
727 const uint8_t rgb1[] = {c1 >> 16 & 0xff, c1 >> 8 & 0xff, c1 & 0xff};
728 const uint8_t rgb2[] = {c2 >> 16 & 0xff, c2 >> 8 & 0xff, c2 & 0xff};
729 mean_err += diff(rgb1, rgb2);
731 src1 += src1_linesize;
732 src2 += src2_linesize;
735 s->total_mean_err += mean_err;
737 av_log(NULL, AV_LOG_INFO, "MEP:%.3f TotalMEP:%.3f\n",
738 mean_err / div, s->total_mean_err / (div * frame_count));
741 static AVFrame *apply_palette(AVFilterLink *inlink, AVFrame *in)
743 AVFilterContext *ctx = inlink->dst;
744 PaletteUseContext *s = ctx->priv;
745 AVFilterLink *outlink = inlink->dst->outputs[0];
747 AVFrame *out = ff_get_video_buffer(outlink, outlink->w, outlink->h);
752 av_frame_copy_props(out, in);
753 if (s->set_frame(s, out, in) < 0) {
758 memcpy(out->data[1], s->palette, AVPALETTE_SIZE);
759 if (s->calc_mean_err)
760 debug_mean_error(s, in, out, inlink->frame_count);
765 static int config_output(AVFilterLink *outlink)
768 AVFilterContext *ctx = outlink->src;
769 PaletteUseContext *s = ctx->priv;
771 outlink->w = ctx->inputs[0]->w;
772 outlink->h = ctx->inputs[0]->h;
774 outlink->time_base = ctx->inputs[0]->time_base;
775 if ((ret = ff_dualinput_init(ctx, &s->dinput)) < 0)
780 static int config_input_palette(AVFilterLink *inlink)
782 AVFilterContext *ctx = inlink->dst;
784 if (inlink->w * inlink->h != AVPALETTE_COUNT) {
785 av_log(ctx, AV_LOG_ERROR,
786 "Palette input must contain exactly %d pixels. "
787 "Specified input has %dx%d=%d pixels\n",
788 AVPALETTE_COUNT, inlink->w, inlink->h,
789 inlink->w * inlink->h);
790 return AVERROR(EINVAL);
795 static void load_palette(PaletteUseContext *s, const AVFrame *palette_frame)
798 const uint32_t *p = (const uint32_t *)palette_frame->data[0];
799 const int p_linesize = palette_frame->linesize[0] >> 2;
802 for (y = 0; y < palette_frame->height; y++) {
803 for (x = 0; x < palette_frame->width; x++)
804 s->palette[i++] = p[x];
810 s->palette_loaded = 1;
813 static AVFrame *load_apply_palette(AVFilterContext *ctx, AVFrame *main,
814 const AVFrame *second)
816 AVFilterLink *inlink = ctx->inputs[0];
817 PaletteUseContext *s = ctx->priv;
818 if (!s->palette_loaded) {
819 load_palette(s, second);
821 return apply_palette(inlink, main);
824 static int filter_frame(AVFilterLink *inlink, AVFrame *in)
826 PaletteUseContext *s = inlink->dst->priv;
827 return ff_dualinput_filter_frame(&s->dinput, inlink, in);
830 #define DEFINE_SET_FRAME(color_search, name, value) \
831 static int set_frame_##name(PaletteUseContext *s, AVFrame *out, AVFrame *in) \
833 return set_frame(s, out, in, value, color_search); \
836 #define DEFINE_SET_FRAME_COLOR_SEARCH(color_search, color_search_macro) \
837 DEFINE_SET_FRAME(color_search_macro, color_search##_##none, DITHERING_NONE) \
838 DEFINE_SET_FRAME(color_search_macro, color_search##_##bayer, DITHERING_BAYER) \
839 DEFINE_SET_FRAME(color_search_macro, color_search##_##heckbert, DITHERING_HECKBERT) \
840 DEFINE_SET_FRAME(color_search_macro, color_search##_##floyd_steinberg, DITHERING_FLOYD_STEINBERG) \
841 DEFINE_SET_FRAME(color_search_macro, color_search##_##sierra2, DITHERING_SIERRA2) \
842 DEFINE_SET_FRAME(color_search_macro, color_search##_##sierra2_4a, DITHERING_SIERRA2_4A) \
844 DEFINE_SET_FRAME_COLOR_SEARCH(nns_iterative, COLOR_SEARCH_NNS_ITERATIVE)
845 DEFINE_SET_FRAME_COLOR_SEARCH(nns_recursive, COLOR_SEARCH_NNS_RECURSIVE)
846 DEFINE_SET_FRAME_COLOR_SEARCH(bruteforce, COLOR_SEARCH_BRUTEFORCE)
848 #define DITHERING_ENTRIES(color_search) { \
849 set_frame_##color_search##_none, \
850 set_frame_##color_search##_bayer, \
851 set_frame_##color_search##_heckbert, \
852 set_frame_##color_search##_floyd_steinberg, \
853 set_frame_##color_search##_sierra2, \
854 set_frame_##color_search##_sierra2_4a, \
857 static const set_frame_func set_frame_lut[NB_COLOR_SEARCHES][NB_DITHERING] = {
858 DITHERING_ENTRIES(nns_iterative),
859 DITHERING_ENTRIES(nns_recursive),
860 DITHERING_ENTRIES(bruteforce),
863 static int dither_value(int p)
865 const int q = p ^ (p >> 3);
866 return (p & 4) >> 2 | (q & 4) >> 1 \
867 | (p & 2) << 1 | (q & 2) << 2 \
868 | (p & 1) << 4 | (q & 1) << 5;
871 static av_cold int init(AVFilterContext *ctx)
873 PaletteUseContext *s = ctx->priv;
874 s->dinput.repeatlast = 1; // only 1 frame in the palette
875 s->dinput.process = load_apply_palette;
877 s->set_frame = set_frame_lut[s->color_search_method][s->dither];
879 if (s->dither == DITHERING_BAYER) {
881 const int delta = 1 << (5 - s->bayer_scale); // to avoid too much luma
883 for (i = 0; i < FF_ARRAY_ELEMS(s->ordered_dither); i++)
884 s->ordered_dither[i] = (dither_value(i) >> s->bayer_scale) - delta;
890 static int request_frame(AVFilterLink *outlink)
892 PaletteUseContext *s = outlink->src->priv;
893 return ff_dualinput_request_frame(&s->dinput, outlink);
896 static av_cold void uninit(AVFilterContext *ctx)
899 PaletteUseContext *s = ctx->priv;
901 ff_dualinput_uninit(&s->dinput);
902 for (i = 0; i < CACHE_SIZE; i++)
903 av_freep(&s->cache[i].entries);
906 static const AVFilterPad paletteuse_inputs[] = {
909 .type = AVMEDIA_TYPE_VIDEO,
910 .filter_frame = filter_frame,
911 .needs_writable = 1, // for error diffusal dithering
914 .type = AVMEDIA_TYPE_VIDEO,
915 .config_props = config_input_palette,
916 .filter_frame = filter_frame,
921 static const AVFilterPad paletteuse_outputs[] = {
924 .type = AVMEDIA_TYPE_VIDEO,
925 .config_props = config_output,
926 .request_frame = request_frame,
931 AVFilter ff_vf_paletteuse = {
932 .name = "paletteuse",
933 .description = NULL_IF_CONFIG_SMALL("Use a palette to downsample an input video stream."),
934 .priv_size = sizeof(PaletteUseContext),
935 .query_formats = query_formats,
938 .inputs = paletteuse_inputs,
939 .outputs = paletteuse_outputs,
940 .priv_class = &paletteuse_class,