FFmpeg coverage

Directory: ../../../ffmpeg/
File: src/libavfilter/vf_palettegen.c
Date: 2024-04-19 07:31:02
Exec Total Coverage
Lines: 210 234 89.7%
Functions: 24 24 100.0%
Branches: 117 144 81.2%
Line Branch Exec Source
1 /*
2 * Copyright (c) 2015 Stupeflix
3 * Copyright (c) 2022 Clément Bœsch <u pkh me>
4 *
5 * This file is part of FFmpeg.
6 *
7 * FFmpeg is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU Lesser General Public
9 * License as published by the Free Software Foundation; either
10 * version 2.1 of the License, or (at your option) any later version.
11 *
12 * FFmpeg is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15 * Lesser General Public License for more details.
16 *
17 * You should have received a copy of the GNU Lesser General Public
18 * License along with FFmpeg; if not, write to the Free Software
19 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20 */
21
22 /**
23 * @file
24 * Generate one palette for a whole video stream.
25 */
26
27 #include "libavutil/avassert.h"
28 #include "libavutil/internal.h"
29 #include "libavutil/mem.h"
30 #include "libavutil/opt.h"
31 #include "libavutil/intreadwrite.h"
32 #include "avfilter.h"
33 #include "formats.h"
34 #include "internal.h"
35 #include "palette.h"
36 #include "video.h"
37
38 /* Reference a color and how much it's used */
39 struct color_ref {
40 uint32_t color;
41 struct Lab lab;
42 int64_t count;
43 };
44
45 /* Store a range of colors */
46 struct range_box {
47 uint32_t color; // average color
48 struct Lab avg; // average color in perceptual OkLab space
49 int major_axis; // best axis candidate for cutting the box
50 int64_t weight; // sum of all the weights of the colors
51 int64_t cut_score; // how likely the box is to be cut down (higher implying more likely)
52 int start; // index in PaletteGenContext->refs
53 int len; // number of referenced colors
54 int sorted_by; // whether range of colors is sorted by red (0), green (1) or blue (2)
55 };
56
57 struct hist_node {
58 struct color_ref *entries;
59 int nb_entries;
60 };
61
62 enum {
63 STATS_MODE_ALL_FRAMES,
64 STATS_MODE_DIFF_FRAMES,
65 STATS_MODE_SINGLE_FRAMES,
66 NB_STATS_MODE
67 };
68
69 #define HIST_SIZE (1<<15)
70
71 typedef struct PaletteGenContext {
72 const AVClass *class;
73
74 int max_colors;
75 int reserve_transparent;
76 int stats_mode;
77
78 AVFrame *prev_frame; // previous frame used for the diff stats_mode
79 struct hist_node histogram[HIST_SIZE]; // histogram/hashtable of the colors
80 struct color_ref **refs; // references of all the colors used in the stream
81 int nb_refs; // number of color references (or number of different colors)
82 struct range_box boxes[256]; // define the segmentation of the colorspace (the final palette)
83 int nb_boxes; // number of boxes (increase will segmenting them)
84 int palette_pushed; // if the palette frame is pushed into the outlink or not
85 uint8_t transparency_color[4]; // background color for transparency
86 } PaletteGenContext;
87
88 #define OFFSET(x) offsetof(PaletteGenContext, x)
89 #define FLAGS AV_OPT_FLAG_FILTERING_PARAM|AV_OPT_FLAG_VIDEO_PARAM
90 static const AVOption palettegen_options[] = {
91 { "max_colors", "set the maximum number of colors to use in the palette", OFFSET(max_colors), AV_OPT_TYPE_INT, {.i64=256}, 2, 256, FLAGS },
92 { "reserve_transparent", "reserve a palette entry for transparency", OFFSET(reserve_transparent), AV_OPT_TYPE_BOOL, {.i64=1}, 0, 1, FLAGS },
93 { "transparency_color", "set a background color for transparency", OFFSET(transparency_color), AV_OPT_TYPE_COLOR, {.str="lime"}, 0, 0, FLAGS },
94 { "stats_mode", "set statistics mode", OFFSET(stats_mode), AV_OPT_TYPE_INT, {.i64=STATS_MODE_ALL_FRAMES}, 0, NB_STATS_MODE-1, FLAGS, .unit = "mode" },
95 { "full", "compute full frame histograms", 0, AV_OPT_TYPE_CONST, {.i64=STATS_MODE_ALL_FRAMES}, INT_MIN, INT_MAX, FLAGS, .unit = "mode" },
96 { "diff", "compute histograms only for the part that differs from previous frame", 0, AV_OPT_TYPE_CONST, {.i64=STATS_MODE_DIFF_FRAMES}, INT_MIN, INT_MAX, FLAGS, .unit = "mode" },
97 { "single", "compute new histogram for each frame", 0, AV_OPT_TYPE_CONST, {.i64=STATS_MODE_SINGLE_FRAMES}, INT_MIN, INT_MAX, FLAGS, .unit = "mode" },
98 { NULL }
99 };
100
101 AVFILTER_DEFINE_CLASS(palettegen);
102
103 2 static int query_formats(AVFilterContext *ctx)
104 {
105 static const enum AVPixelFormat in_fmts[] = {AV_PIX_FMT_RGB32, AV_PIX_FMT_NONE};
106 static const enum AVPixelFormat out_fmts[] = {AV_PIX_FMT_RGB32, AV_PIX_FMT_NONE};
107 int ret;
108
109
1/2
✗ Branch 2 not taken.
✓ Branch 3 taken 2 times.
 2 if ((ret = ff_formats_ref(ff_make_format_list(in_fmts) , &ctx->inputs[0]->outcfg.formats)) < 0)
110 ✗ return ret;
111
1/2
✗ Branch 2 not taken.
✓ Branch 3 taken 2 times.
 2 if ((ret = ff_formats_ref(ff_make_format_list(out_fmts), &ctx->outputs[0]->incfg.formats)) < 0)
112 ✗ return ret;
113 2 return 0;
114 }
115
116 typedef int (*cmp_func)(const void *, const void *);
117
118 #define DECLARE_CMP_FUNC(k0, k1, k2) \
119 static int cmp_##k0##k1##k2(const void *pa, const void *pb) \
120 { \
121 const struct color_ref * const *a = pa; \
122 const struct color_ref * const *b = pb; \
123 const int c0 = FFDIFFSIGN((*a)->lab.k0, (*b)->lab.k0); \
124 const int c1 = FFDIFFSIGN((*a)->lab.k1, (*b)->lab.k1); \
125 const int c2 = FFDIFFSIGN((*a)->lab.k2, (*b)->lab.k2); \
126 return c0 ? c0 : c1 ? c1 : c2; \
127 }
128
129
4/4
✓ Branch 0 taken 19743 times.
✓ Branch 1 taken 872344 times.
✓ Branch 2 taken 19711 times.
✓ Branch 3 taken 32 times.
 892087 DECLARE_CMP_FUNC(L, a, b)
130
4/4
✓ Branch 0 taken 14185 times.
✓ Branch 1 taken 385091 times.
✓ Branch 2 taken 14183 times.
✓ Branch 3 taken 2 times.
 399276 DECLARE_CMP_FUNC(L, b, a)
131
4/4
✓ Branch 0 taken 2244 times.
✓ Branch 1 taken 127244 times.
✓ Branch 2 taken 2240 times.
✓ Branch 3 taken 4 times.
 129488 DECLARE_CMP_FUNC(a, L, b)
132
4/4
✓ Branch 0 taken 3596 times.
✓ Branch 1 taken 221279 times.
✓ Branch 2 taken 2886 times.
✓ Branch 3 taken 710 times.
 224875 DECLARE_CMP_FUNC(a, b, L)
133
3/4
✓ Branch 0 taken 3083 times.
✓ Branch 1 taken 91466 times.
✓ Branch 2 taken 3083 times.
✗ Branch 3 not taken.
 94549 DECLARE_CMP_FUNC(b, L, a)
134
4/4
✓ Branch 0 taken 9979 times.
✓ Branch 1 taken 319698 times.
✓ Branch 2 taken 9052 times.
✓ Branch 3 taken 927 times.
 329677 DECLARE_CMP_FUNC(b, a, L)
135
136 enum { ID_XYZ, ID_XZY, ID_ZXY, ID_YXZ, ID_ZYX, ID_YZX };
137 static const char * const sortstr[] = { "Lab", "Lba", "bLa", "aLb", "baL", "abL" };
138
139 static const cmp_func cmp_funcs[] = {
140 [ID_XYZ] = cmp_Lab,
141 [ID_XZY] = cmp_Lba,
142 [ID_ZXY] = cmp_bLa,
143 [ID_YXZ] = cmp_aLb,
144 [ID_ZYX] = cmp_baL,
145 [ID_YZX] = cmp_abL,
146 };
147
148 /*
149 * Return an identifier for the order of x, y, z (from higher to lower),
150 * preferring x over y and y over z in case of equality.
151 */
152 764 static int sort3id(int64_t x, int64_t y, int64_t z)
153 {
154
2/2
✓ Branch 0 taken 400 times.
✓ Branch 1 taken 364 times.
 764 if (x >= y) {
155
2/2
✓ Branch 0 taken 209 times.
✓ Branch 1 taken 191 times.
 400 if (y >= z) return ID_XYZ;
156
2/2
✓ Branch 0 taken 130 times.
✓ Branch 1 taken 61 times.
 191 if (x >= z) return ID_XZY;
157 61 return ID_ZXY;
158 }
159
2/2
✓ Branch 0 taken 118 times.
✓ Branch 1 taken 246 times.
 364 if (x >= z) return ID_YXZ;
160
2/2
✓ Branch 0 taken 138 times.
✓ Branch 1 taken 108 times.
 246 if (y >= z) return ID_YZX;
161 108 return ID_ZYX;
162 }
163
164 /**
165 * Simple color comparison for sorting the final palette
166 */
167 2462 static int cmp_color(const void *a, const void *b)
168 {
169 2462 const struct range_box *box1 = a;
170 2462 const struct range_box *box2 = b;
171 2462 return FFDIFFSIGN(box1->color, box2->color);
172 }
173
174 764 static void compute_box_stats(PaletteGenContext *s, struct range_box *box)
175 {
176 764 int64_t er2[3] = {0};
177
178 /* Compute average color */
179 764 int64_t sL = 0, sa = 0, sb = 0;
180 764 box->weight = 0;
181
2/2
✓ Branch 0 taken 418470 times.
✓ Branch 1 taken 764 times.
 419234 for (int i = box->start; i < box->start + box->len; i++) {
182 418470 const struct color_ref *ref = s->refs[i];
183 418470 sL += ref->lab.L * ref->count;
184 418470 sa += ref->lab.a * ref->count;
185 418470 sb += ref->lab.b * ref->count;
186 418470 box->weight += ref->count;
187 }
188 764 box->avg.L = sL / box->weight;
189 764 box->avg.a = sa / box->weight;
190 764 box->avg.b = sb / box->weight;
191
192 /* Compute squared error of each color channel */
193
2/2
✓ Branch 0 taken 418470 times.
✓ Branch 1 taken 764 times.
 419234 for (int i = box->start; i < box->start + box->len; i++) {
194 418470 const struct color_ref *ref = s->refs[i];
195 418470 const int64_t dL = ref->lab.L - box->avg.L;
196 418470 const int64_t da = ref->lab.a - box->avg.a;
197 418470 const int64_t db = ref->lab.b - box->avg.b;
198 418470 er2[0] += dL * dL * ref->count;
199 418470 er2[1] += da * da * ref->count;
200 418470 er2[2] += db * db * ref->count;
201 }
202
203 /* Define the best axis candidate for cutting the box */
204 764 box->major_axis = sort3id(er2[0], er2[1], er2[2]);
205
206 /* The box that has the axis with the biggest error amongst all boxes will but cut down */
207 764 box->cut_score = FFMAX3(er2[0], er2[1], er2[2]);
208 764 }
209
210 /**
211 * Find the next box to split: pick the one with the highest cut score
212 */
213 381 static int get_next_box_id_to_split(PaletteGenContext *s)
214 {
215 381 int best_box_id = -1;
216 381 int64_t max_score = -1;
217
218
2/2
✓ Branch 0 taken 2 times.
✓ Branch 1 taken 379 times.
 381 if (s->nb_boxes == s->max_colors - s->reserve_transparent)
219 2 return -1;
220
221
2/2
✓ Branch 0 taken 40511 times.
✓ Branch 1 taken 379 times.
 40890 for (int box_id = 0; box_id < s->nb_boxes; box_id++) {
222 40511 const struct range_box *box = &s->boxes[box_id];
223
3/4
✓ Branch 0 taken 40511 times.
✗ Branch 1 not taken.
✓ Branch 2 taken 1490 times.
✓ Branch 3 taken 39021 times.
 40511 if (s->boxes[box_id].len >= 2 && box->cut_score > max_score) {
224 1490 best_box_id = box_id;
225 1490 max_score = box->cut_score;
226 }
227 }
228 379 return best_box_id;
229 }
230
231 /**
232 * Split given box in two at position n. The original box becomes the left part
233 * of the split, and the new index box is the right part.
234 */
235 381 static void split_box(PaletteGenContext *s, struct range_box *box, int n)
236 {
237 381 struct range_box *new_box = &s->boxes[s->nb_boxes++];
238 381 new_box->start = n + 1;
239 381 new_box->len = box->start + box->len - new_box->start;
240 381 new_box->sorted_by = box->sorted_by;
241 381 box->len -= new_box->len;
242
243
1/2
✗ Branch 0 not taken.
✓ Branch 1 taken 381 times.
 381 av_assert0(box->len >= 1);
244
1/2
✗ Branch 0 not taken.
✓ Branch 1 taken 381 times.
 381 av_assert0(new_box->len >= 1);
245
246 381 compute_box_stats(s, box);
247 381 compute_box_stats(s, new_box);
248 381 }
249
250 /**
251 * Write the palette into the output frame.
252 */
253 2 static void write_palette(AVFilterContext *ctx, AVFrame *out)
254 {
255 2 const PaletteGenContext *s = ctx->priv;
256 2 int box_id = 0;
257 2 uint32_t *pal = (uint32_t *)out->data[0];
258 2 const int pal_linesize = out->linesize[0] >> 2;
259 2 uint32_t last_color = 0;
260
261
2/2
✓ Branch 0 taken 32 times.
✓ Branch 1 taken 2 times.
 34 for (int y = 0; y < out->height; y++) {
262
2/2
✓ Branch 0 taken 512 times.
✓ Branch 1 taken 32 times.
 544 for (int x = 0; x < out->width; x++) {
263
2/2
✓ Branch 0 taken 383 times.
✓ Branch 1 taken 129 times.
 512 if (box_id < s->nb_boxes) {
264 383 pal[x] = s->boxes[box_id++].color;
265
5/6
✓ Branch 0 taken 24 times.
✓ Branch 1 taken 359 times.
✓ Branch 2 taken 22 times.
✓ Branch 3 taken 2 times.
✗ Branch 4 not taken.
✓ Branch 5 taken 381 times.
 383 if ((x || y) && pal[x] == last_color)
266 ✗ av_log(ctx, AV_LOG_WARNING, "Duped color: %08"PRIX32"\n", pal[x]);
267 383 last_color = pal[x];
268 } else {
269 129 pal[x] = last_color; // pad with last color
270 }
271 }
272 32 pal += pal_linesize;
273 }
274
275
2/2
✓ Branch 0 taken 1 times.
✓ Branch 1 taken 1 times.
 2 if (s->reserve_transparent) {
276
1/2
✗ Branch 0 not taken.
✓ Branch 1 taken 1 times.
 1 av_assert0(s->nb_boxes < 256);
277 1 pal[out->width - pal_linesize - 1] = AV_RB32(&s->transparency_color) >> 8;
278 }
279 2 }
280
281 /**
282 * Crawl the histogram to get all the defined colors, and create a linear list
283 * of them (each color reference entry is a pointer to the value in the
284 * histogram/hash table).
285 */
286 2 static struct color_ref **load_color_refs(const struct hist_node *hist, int nb_refs)
287 {
288 2 int k = 0;
289 2 struct color_ref **refs = av_malloc_array(nb_refs, sizeof(*refs));
290
291
1/2
✗ Branch 0 not taken.
✓ Branch 1 taken 2 times.
 2 if (!refs)
292 ✗ return NULL;
293
294
2/2
✓ Branch 0 taken 65536 times.
✓ Branch 1 taken 2 times.
 65538 for (int j = 0; j < HIST_SIZE; j++) {
295 65536 const struct hist_node *node = &hist[j];
296
297
2/2
✓ Branch 0 taken 44830 times.
✓ Branch 1 taken 65536 times.
 110366 for (int i = 0; i < node->nb_entries; i++)
298 44830 refs[k++] = &node->entries[i];
299 }
300
301 2 return refs;
302 }
303
304 2 static double set_colorquant_ratio_meta(AVFrame *out, int nb_out, int nb_in)
305 {
306 char buf[32];
307 2 const double ratio = (double)nb_out / nb_in;
308 2 snprintf(buf, sizeof(buf), "%f", ratio);
309 2 av_dict_set(&out->metadata, "lavfi.color_quant_ratio", buf, 0);
310 2 return ratio;
311 }
312
313 /**
314 * Main function implementing the Median Cut Algorithm defined by Paul Heckbert
315 * in Color Image Quantization for Frame Buffer Display (1982)
316 */
317 2 static AVFrame *get_palette_frame(AVFilterContext *ctx)
318 {
319 AVFrame *out;
320 2 PaletteGenContext *s = ctx->priv;
321 2 AVFilterLink *outlink = ctx->outputs[0];
322 double ratio;
323 2 int box_id = 0;
324 struct range_box *box;
325
326 /* reference only the used colors from histogram */
327 2 s->refs = load_color_refs(s->histogram, s->nb_refs);
328
1/2
✗ Branch 0 not taken.
✓ Branch 1 taken 2 times.
 2 if (!s->refs) {
329 ✗ av_log(ctx, AV_LOG_ERROR, "Unable to allocate references for %d different colors\n", s->nb_refs);
330 ✗ return NULL;
331 }
332
333 /* create the palette frame */
334 2 out = ff_get_video_buffer(outlink, outlink->w, outlink->h);
335
1/2
✗ Branch 0 not taken.
✓ Branch 1 taken 2 times.
 2 if (!out)
336 ✗ return NULL;
337 2 out->pts = 0;
338
339 /* set first box for 0..nb_refs */
340 2 box = &s->boxes[box_id];
341 2 box->len = s->nb_refs;
342 2 box->sorted_by = -1;
343 2 compute_box_stats(s, box);
344 2 s->nb_boxes = 1;
345
346
3/4
✓ Branch 0 taken 381 times.
✓ Branch 1 taken 2 times.
✓ Branch 2 taken 381 times.
✗ Branch 3 not taken.
 383 while (box && box->len > 1) {
347 int i;
348 int64_t median, weight;
349
350 ff_dlog(ctx, "box #%02X [%6d..%-6d] (%6d) w:%-6"PRIu64" sort by %s (already sorted:%c) ",
351 box_id, box->start, box->start + box->len - 1, box->len, box->weight,
352 sortstr[box->major_axis], box->sorted_by == box->major_axis ? 'y':'n');
353
354 /* sort the range by its major axis if it's not already sorted */
355
2/2
✓ Branch 0 taken 248 times.
✓ Branch 1 taken 133 times.
 381 if (box->sorted_by != box->major_axis) {
356 248 cmp_func cmpf = cmp_funcs[box->major_axis];
357 248 qsort(&s->refs[box->start], box->len, sizeof(struct color_ref *), cmpf);
358 248 box->sorted_by = box->major_axis;
359 }
360
361 /* locate the median where to split */
362 381 median = (box->weight + 1) >> 1;
363 381 weight = 0;
364 /* if you have 2 boxes, the maximum is actually #0: you must have at
365 * least 1 color on each side of the split, hence the -2 */
366
1/2
✓ Branch 0 taken 200876 times.
✗ Branch 1 not taken.
 200876 for (i = box->start; i < box->start + box->len - 2; i++) {
367 200876 weight += s->refs[i]->count;
368
2/2
✓ Branch 0 taken 381 times.
✓ Branch 1 taken 200495 times.
 200876 if (weight > median)
369 381 break;
370 }
371 ff_dlog(ctx, "split @ i=%-6d with w=%-6"PRIu64" (target=%6"PRIu64")\n", i, weight, median);
372 381 split_box(s, box, i);
373
374 381 box_id = get_next_box_id_to_split(s);
375
2/2
✓ Branch 0 taken 379 times.
✓ Branch 1 taken 2 times.
 381 box = box_id >= 0 ? &s->boxes[box_id] : NULL;
376 }
377
378 2 ratio = set_colorquant_ratio_meta(out, s->nb_boxes, s->nb_refs);
379 2 av_log(ctx, AV_LOG_INFO, "%d%s colors generated out of %d colors; ratio=%f\n",
380
2/2
✓ Branch 0 taken 1 times.
✓ Branch 1 taken 1 times.
 2 s->nb_boxes, s->reserve_transparent ? "(+1)" : "", s->nb_refs, ratio);
381
382
2/2
✓ Branch 0 taken 383 times.
✓ Branch 1 taken 2 times.
 385 for (int i = 0; i < s->nb_boxes; i++)
383 383 s->boxes[i].color = 0xffU<<24 | ff_oklab_int_to_srgb_u8(s->boxes[i].avg);
384
385 2 qsort(s->boxes, s->nb_boxes, sizeof(*s->boxes), cmp_color);
386
387 2 write_palette(ctx, out);
388
389 2 return out;
390 }
391
392 /**
393 * Locate the color in the hash table and increment its counter.
394 */
395 4329458 static int color_inc(struct hist_node *hist, uint32_t color)
396 {
397 4329458 const uint32_t hash = ff_lowbias32(color) & (HIST_SIZE - 1);
398 4329458 struct hist_node *node = &hist[hash];
399 struct color_ref *e;
400
401
2/2
✓ Branch 0 taken 4990540 times.
✓ Branch 1 taken 44830 times.
 5035370 for (int i = 0; i < node->nb_entries; i++) {
402 4990540 e = &node->entries[i];
403
2/2
✓ Branch 0 taken 4284628 times.
✓ Branch 1 taken 705912 times.
 4990540 if (e->color == color) {
404 4284628 e->count++;
405 4284628 return 0;
406 }
407 }
408
409 44830 e = av_dynarray2_add((void**)&node->entries, &node->nb_entries,
410 sizeof(*node->entries), NULL);
411
1/2
✗ Branch 0 not taken.
✓ Branch 1 taken 44830 times.
 44830 if (!e)
412 ✗ return AVERROR(ENOMEM);
413 44830 e->color = color;
414 44830 e->lab = ff_srgb_u8_to_oklab_int(color);
415 44830 e->count = 1;
416 44830 return 1;
417 }
418
419 /**
420 * Update histogram when pixels differ from previous frame.
421 */
422 70 static int update_histogram_diff(struct hist_node *hist,
423 const AVFrame *f1, const AVFrame *f2)
424 {
425 70 int x, y, ret, nb_diff_colors = 0;
426
427
2/2
✓ Branch 0 taken 12600 times.
✓ Branch 1 taken 70 times.
 12670 for (y = 0; y < f1->height; y++) {
428 12600 const uint32_t *p = (const uint32_t *)(f1->data[0] + y*f1->linesize[0]);
429 12600 const uint32_t *q = (const uint32_t *)(f2->data[0] + y*f2->linesize[0]);
430
431
2/2
✓ Branch 0 taken 4032000 times.
✓ Branch 1 taken 12600 times.
 4044600 for (x = 0; x < f1->width; x++) {
432
2/2
✓ Branch 0 taken 3849742 times.
✓ Branch 1 taken 182258 times.
 4032000 if (p[x] == q[x])
433 3849742 continue;
434 182258 ret = color_inc(hist, p[x]);
435
1/2
✗ Branch 0 not taken.
✓ Branch 1 taken 182258 times.
 182258 if (ret < 0)
436 ✗ return ret;
437 182258 nb_diff_colors += ret;
438 }
439 }
440 70 return nb_diff_colors;
441 }
442
443 /**
444 * Simple histogram of the frame.
445 */
446 72 static int update_histogram_frame(struct hist_node *hist, const AVFrame *f)
447 {
448 72 int x, y, ret, nb_diff_colors = 0;
449
450
2/2
✓ Branch 0 taken 12960 times.
✓ Branch 1 taken 72 times.
 13032 for (y = 0; y < f->height; y++) {
451 12960 const uint32_t *p = (const uint32_t *)(f->data[0] + y*f->linesize[0]);
452
453
2/2
✓ Branch 0 taken 4147200 times.
✓ Branch 1 taken 12960 times.
 4160160 for (x = 0; x < f->width; x++) {
454 4147200 ret = color_inc(hist, p[x]);
455
1/2
✗ Branch 0 not taken.
✓ Branch 1 taken 4147200 times.
 4147200 if (ret < 0)
456 ✗ return ret;
457 4147200 nb_diff_colors += ret;
458 }
459 }
460 72 return nb_diff_colors;
461 }
462
463 /**
464 * Update the histogram for each passing frame. No frame will be pushed here.
465 */
466 142 static int filter_frame(AVFilterLink *inlink, AVFrame *in)
467 {
468 142 AVFilterContext *ctx = inlink->dst;
469 142 PaletteGenContext *s = ctx->priv;
470 int ret;
471
472
1/4
✗ Branch 0 not taken.
✓ Branch 1 taken 142 times.
✗ Branch 2 not taken.
✗ Branch 3 not taken.
 142 if (in->color_trc != AVCOL_TRC_UNSPECIFIED && in->color_trc != AVCOL_TRC_IEC61966_2_1)
473 ✗ av_log(ctx, AV_LOG_WARNING, "The input frame is not in sRGB, colors may be off\n");
474
475 70 ret = s->prev_frame ? update_histogram_diff(s->histogram, s->prev_frame, in)
476
2/2
✓ Branch 0 taken 70 times.
✓ Branch 1 taken 72 times.
 142 : update_histogram_frame(s->histogram, in);
477
2/2
✓ Branch 0 taken 137 times.
✓ Branch 1 taken 5 times.
 142 if (ret > 0)
478 137 s->nb_refs += ret;
479
480
2/2
✓ Branch 0 taken 71 times.
✓ Branch 1 taken 71 times.
 142 if (s->stats_mode == STATS_MODE_DIFF_FRAMES) {
481 71 av_frame_free(&s->prev_frame);
482 71 s->prev_frame = in;
483
1/4
✗ Branch 0 not taken.
✓ Branch 1 taken 71 times.
✗ Branch 2 not taken.
✗ Branch 3 not taken.
 71 } else if (s->stats_mode == STATS_MODE_SINGLE_FRAMES && s->nb_refs > 0) {
484 AVFrame *out;
485 int i;
486
487 ✗ out = get_palette_frame(ctx);
488 ✗ out->pts = in->pts;
489 ✗ av_frame_free(&in);
490 ✗ ret = ff_filter_frame(ctx->outputs[0], out);
491 ✗ for (i = 0; i < HIST_SIZE; i++)
492 ✗ av_freep(&s->histogram[i].entries);
493 ✗ av_freep(&s->refs);
494 ✗ s->nb_refs = 0;
495 ✗ s->nb_boxes = 0;
496 ✗ memset(s->boxes, 0, sizeof(s->boxes));
497 ✗ memset(s->histogram, 0, sizeof(s->histogram));
498 } else {
499 71 av_frame_free(&in);
500 }
501
502 142 return ret;
503 }
504
505 /**
506 * Returns only one frame at the end containing the full palette.
507 */
508 146 static int request_frame(AVFilterLink *outlink)
509 {
510 146 AVFilterContext *ctx = outlink->src;
511 146 AVFilterLink *inlink = ctx->inputs[0];
512 146 PaletteGenContext *s = ctx->priv;
513 int r;
514
515 146 r = ff_request_frame(inlink);
516
6/8
✓ Branch 0 taken 4 times.
✓ Branch 1 taken 142 times.
✓ Branch 2 taken 2 times.
✓ Branch 3 taken 2 times.
✓ Branch 4 taken 2 times.
✗ Branch 5 not taken.
✓ Branch 6 taken 2 times.
✗ Branch 7 not taken.
 146 if (r == AVERROR_EOF && !s->palette_pushed && s->nb_refs && s->stats_mode != STATS_MODE_SINGLE_FRAMES) {
517 2 r = ff_filter_frame(outlink, get_palette_frame(ctx));
518 2 s->palette_pushed = 1;
519 2 return r;
520 }
521 144 return r;
522 }
523
524 /**
525 * The output is one simple 16x16 squared-pixels palette.
526 */
527 2 static int config_output(AVFilterLink *outlink)
528 {
529 2 outlink->w = outlink->h = 16;
530 2 outlink->sample_aspect_ratio = av_make_q(1, 1);
531 2 return 0;
532 }
533
534 4 static int init(AVFilterContext *ctx)
535 {
536 4 PaletteGenContext* s = ctx->priv;
537
538
1/2
✗ Branch 0 not taken.
✓ Branch 1 taken 4 times.
 4 if (s->max_colors - s->reserve_transparent < 2) {
539 ✗ av_log(ctx, AV_LOG_ERROR, "max_colors=2 is only allowed without reserving a transparent color slot\n");
540 ✗ return AVERROR(EINVAL);
541 }
542
543 4 return 0;
544 }
545
546 4 static av_cold void uninit(AVFilterContext *ctx)
547 {
548 int i;
549 4 PaletteGenContext *s = ctx->priv;
550
551
2/2
✓ Branch 0 taken 131072 times.
✓ Branch 1 taken 4 times.
 131076 for (i = 0; i < HIST_SIZE; i++)
552 131072 av_freep(&s->histogram[i].entries);
553 4 av_freep(&s->refs);
554 4 av_frame_free(&s->prev_frame);
555 4 }
556
557 static const AVFilterPad palettegen_inputs[] = {
558 {
559 .name = "default",
560 .type = AVMEDIA_TYPE_VIDEO,
561 .filter_frame = filter_frame,
562 },
563 };
564
565 static const AVFilterPad palettegen_outputs[] = {
566 {
567 .name = "default",
568 .type = AVMEDIA_TYPE_VIDEO,
569 .config_props = config_output,
570 .request_frame = request_frame,
571 },
572 };
573
574 const AVFilter ff_vf_palettegen = {
575 .name = "palettegen",
576 .description = NULL_IF_CONFIG_SMALL("Find the optimal palette for a given stream."),
577 .priv_size = sizeof(PaletteGenContext),
578 .init = init,
579 .uninit = uninit,
580 FILTER_INPUTS(palettegen_inputs),
581 FILTER_OUTPUTS(palettegen_outputs),
582 FILTER_QUERY_FUNC(query_formats),
583 .priv_class = &palettegen_class,
584 };
585