2 * Copyright (c) 2011 Stefano Sabatini
4 * This file is part of FFmpeg.
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.
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.
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
23 * filter for selecting which frame passes in the filterchain
26 #include "config_components.h"
28 #include "libavutil/avstring.h"
29 #include "libavutil/eval.h"
30 #include "libavutil/fifo.h"
31 #include "libavutil/imgutils.h"
32 #include "libavutil/internal.h"
33 #include "libavutil/opt.h"
34 #include "libavutil/pixdesc.h"
40 #include "scene_sad.h"
42 static const char *const var_names[] = {
45 "pts", ///< original pts in the file of the frame
46 "start_pts", ///< first PTS in the stream, expressed in TB units
47 "prev_pts", ///< previous frame PTS
48 "prev_selected_pts", ///< previous selected frame PTS
50 "t", ///< timestamp expressed in seconds
51 "start_t", ///< first PTS in the stream, expressed in seconds
52 "prev_t", ///< previous frame time
53 "prev_selected_t", ///< previously selected time
55 "pict_type", ///< the type of picture in the movie
71 "interlace_type", ///< the frame interlace type
76 "consumed_samples_n",///< number of samples consumed by the filter (only audio)
77 "samples_n", ///< number of samples in the current frame (only audio)
78 "sample_rate", ///< sample rate (only audio)
80 "n", ///< frame number (starting from zero)
81 "selected_n", ///< selected frame number (starting from zero)
82 "prev_selected_n", ///< number of the last selected frame
84 "key", ///< tell if the frame is a key frame
86 "pos", ///< original position in the file of the frame
91 "concatdec_select", ///< frame is within the interval set by the concat demuxer
102 VAR_PREV_SELECTED_PTS,
126 VAR_INTERLACE_TYPE_P,
127 VAR_INTERLACE_TYPE_T,
128 VAR_INTERLACE_TYPE_B,
130 VAR_CONSUMED_SAMPLES_N,
145 VAR_CONCATDEC_SELECT,
150 typedef struct SelectContext {
151 const AVClass *class;
154 double var_values[VAR_VARS_NB];
159 int do_scene_detect; ///< 1 if the expression requires scene detection variables, 0 otherwise
160 ff_scene_sad_fn sad; ///< Sum of the absolute difference function (scene detect only)
161 double prev_mafd; ///< previous MAFD (scene detect only)
162 AVFrame *prev_picref; ///< previous frame (scene detect only)
164 int select_out; ///< mark the selected output pad index
168 #define OFFSET(x) offsetof(SelectContext, x)
169 #define DEFINE_OPTIONS(filt_name, FLAGS) \
170 static const AVOption filt_name##_options[] = { \
171 { "expr", "set an expression to use for selecting frames", OFFSET(expr_str), AV_OPT_TYPE_STRING, { .str = "1" }, .flags=FLAGS }, \
172 { "e", "set an expression to use for selecting frames", OFFSET(expr_str), AV_OPT_TYPE_STRING, { .str = "1" }, .flags=FLAGS }, \
173 { "outputs", "set the number of outputs", OFFSET(nb_outputs), AV_OPT_TYPE_INT, {.i64 = 1}, 1, INT_MAX, .flags=FLAGS }, \
174 { "n", "set the number of outputs", OFFSET(nb_outputs), AV_OPT_TYPE_INT, {.i64 = 1}, 1, INT_MAX, .flags=FLAGS }, \
178 static int request_frame(AVFilterLink *outlink);
180 static av_cold int init(AVFilterContext *ctx)
182 SelectContext *select = ctx->priv;
185 if ((ret = av_expr_parse(&select->expr, select->expr_str,
186 var_names, NULL, NULL, NULL, NULL, 0, ctx)) < 0) {
187 av_log(ctx, AV_LOG_ERROR, "Error while parsing expression '%s'\n",
191 select->do_scene_detect = !!strstr(select->expr_str, "scene");
193 for (i = 0; i < select->nb_outputs; i++) {
194 AVFilterPad pad = { 0 };
196 pad.name = av_asprintf("output%d", i);
198 return AVERROR(ENOMEM);
199 pad.type = ctx->filter->inputs[0].type;
200 pad.request_frame = request_frame;
201 if ((ret = ff_append_outpad_free_name(ctx, &pad)) < 0)
208 #define INTERLACE_TYPE_P 0
209 #define INTERLACE_TYPE_T 1
210 #define INTERLACE_TYPE_B 2
212 static int config_input(AVFilterLink *inlink)
214 SelectContext *select = inlink->dst->priv;
215 const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(inlink->format);
216 int is_yuv = !(desc->flags & AV_PIX_FMT_FLAG_RGB) &&
217 (desc->flags & AV_PIX_FMT_FLAG_PLANAR) &&
218 desc->nb_components >= 3;
220 select->bitdepth = desc->comp[0].depth;
221 select->nb_planes = is_yuv ? 1 : av_pix_fmt_count_planes(inlink->format);
223 for (int plane = 0; plane < select->nb_planes; plane++) {
224 ptrdiff_t line_size = av_image_get_linesize(inlink->format, inlink->w, plane);
225 int vsub = desc->log2_chroma_h;
227 select->width[plane] = line_size >> (select->bitdepth > 8);
228 select->height[plane] = plane == 1 || plane == 2 ? AV_CEIL_RSHIFT(inlink->h, vsub) : inlink->h;
231 select->var_values[VAR_N] = 0.0;
232 select->var_values[VAR_SELECTED_N] = 0.0;
234 select->var_values[VAR_TB] = av_q2d(inlink->time_base);
236 select->var_values[VAR_PREV_PTS] = NAN;
237 select->var_values[VAR_PREV_SELECTED_PTS] = NAN;
238 select->var_values[VAR_PREV_SELECTED_T] = NAN;
239 select->var_values[VAR_PREV_T] = NAN;
240 select->var_values[VAR_START_PTS] = NAN;
241 select->var_values[VAR_START_T] = NAN;
243 select->var_values[VAR_I] = AV_PICTURE_TYPE_I;
244 select->var_values[VAR_P] = AV_PICTURE_TYPE_P;
245 select->var_values[VAR_B] = AV_PICTURE_TYPE_B;
246 select->var_values[VAR_SI] = AV_PICTURE_TYPE_SI;
247 select->var_values[VAR_SP] = AV_PICTURE_TYPE_SP;
248 select->var_values[VAR_BI] = AV_PICTURE_TYPE_BI;
249 select->var_values[VAR_PICT_TYPE_I] = AV_PICTURE_TYPE_I;
250 select->var_values[VAR_PICT_TYPE_P] = AV_PICTURE_TYPE_P;
251 select->var_values[VAR_PICT_TYPE_B] = AV_PICTURE_TYPE_B;
252 select->var_values[VAR_PICT_TYPE_SI] = AV_PICTURE_TYPE_SI;
253 select->var_values[VAR_PICT_TYPE_SP] = AV_PICTURE_TYPE_SP;
254 select->var_values[VAR_PICT_TYPE_BI] = AV_PICTURE_TYPE_BI;
256 select->var_values[VAR_INTERLACE_TYPE_P] = INTERLACE_TYPE_P;
257 select->var_values[VAR_INTERLACE_TYPE_T] = INTERLACE_TYPE_T;
258 select->var_values[VAR_INTERLACE_TYPE_B] = INTERLACE_TYPE_B;
260 select->var_values[VAR_PICT_TYPE] = NAN;
261 select->var_values[VAR_INTERLACE_TYPE] = NAN;
262 select->var_values[VAR_SCENE] = NAN;
263 select->var_values[VAR_CONSUMED_SAMPLES_N] = NAN;
264 select->var_values[VAR_SAMPLES_N] = NAN;
266 select->var_values[VAR_SAMPLE_RATE] =
267 inlink->type == AVMEDIA_TYPE_AUDIO ? inlink->sample_rate : NAN;
269 if (CONFIG_SELECT_FILTER && select->do_scene_detect) {
270 select->sad = ff_scene_sad_get_fn(select->bitdepth == 8 ? 8 : 16);
272 return AVERROR(EINVAL);
277 static double get_scene_score(AVFilterContext *ctx, AVFrame *frame)
280 SelectContext *select = ctx->priv;
281 AVFrame *prev_picref = select->prev_picref;
284 frame->height == prev_picref->height &&
285 frame->width == prev_picref->width) {
290 for (int plane = 0; plane < select->nb_planes; plane++) {
292 select->sad(prev_picref->data[plane], prev_picref->linesize[plane],
293 frame->data[plane], frame->linesize[plane],
294 select->width[plane], select->height[plane], &plane_sad);
296 count += select->width[plane] * select->height[plane];
299 mafd = (double)sad / count / (1ULL << (select->bitdepth - 8));
300 diff = fabs(mafd - select->prev_mafd);
301 ret = av_clipf(FFMIN(mafd, diff) / 100., 0, 1);
302 select->prev_mafd = mafd;
303 av_frame_free(&prev_picref);
305 select->prev_picref = av_frame_clone(frame);
309 static double get_concatdec_select(AVFrame *frame, int64_t pts)
311 AVDictionary *metadata = frame->metadata;
312 AVDictionaryEntry *start_time_entry = av_dict_get(metadata, "lavf.concatdec.start_time", NULL, 0);
313 AVDictionaryEntry *duration_entry = av_dict_get(metadata, "lavf.concatdec.duration", NULL, 0);
314 if (start_time_entry) {
315 int64_t start_time = strtoll(start_time_entry->value, NULL, 10);
316 if (pts >= start_time) {
317 if (duration_entry) {
318 int64_t duration = strtoll(duration_entry->value, NULL, 10);
319 if (pts < start_time + duration)
331 static void select_frame(AVFilterContext *ctx, AVFrame *frame)
333 SelectContext *select = ctx->priv;
334 AVFilterLink *inlink = ctx->inputs[0];
337 if (isnan(select->var_values[VAR_START_PTS]))
338 select->var_values[VAR_START_PTS] = TS2D(frame->pts);
339 if (isnan(select->var_values[VAR_START_T]))
340 select->var_values[VAR_START_T] = TS2D(frame->pts) * av_q2d(inlink->time_base);
342 select->var_values[VAR_N ] = inlink->frame_count_out;
343 select->var_values[VAR_PTS] = TS2D(frame->pts);
344 select->var_values[VAR_T ] = TS2D(frame->pts) * av_q2d(inlink->time_base);
346 FF_DISABLE_DEPRECATION_WARNINGS
347 select->var_values[VAR_POS] = frame->pkt_pos == -1 ? NAN : frame->pkt_pos;
348 FF_ENABLE_DEPRECATION_WARNINGS
350 select->var_values[VAR_KEY] = !!(frame->flags & AV_FRAME_FLAG_KEY);
351 select->var_values[VAR_CONCATDEC_SELECT] = get_concatdec_select(frame, av_rescale_q(frame->pts, inlink->time_base, AV_TIME_BASE_Q));
353 switch (inlink->type) {
354 case AVMEDIA_TYPE_AUDIO:
355 select->var_values[VAR_SAMPLES_N] = frame->nb_samples;
358 case AVMEDIA_TYPE_VIDEO:
359 select->var_values[VAR_INTERLACE_TYPE] =
360 !(frame->flags & AV_FRAME_FLAG_INTERLACED) ? INTERLACE_TYPE_P :
361 (frame->flags & AV_FRAME_FLAG_TOP_FIELD_FIRST) ? INTERLACE_TYPE_T : INTERLACE_TYPE_B;
362 select->var_values[VAR_PICT_TYPE] = frame->pict_type;
363 if (select->do_scene_detect) {
365 select->var_values[VAR_SCENE] = get_scene_score(ctx, frame);
366 // TODO: document metadata
367 snprintf(buf, sizeof(buf), "%f", select->var_values[VAR_SCENE]);
368 av_dict_set(&frame->metadata, "lavfi.scene_score", buf, 0);
373 select->select = res = av_expr_eval(select->expr, select->var_values, NULL);
374 av_log(inlink->dst, AV_LOG_DEBUG,
375 "n:%f pts:%f t:%f key:%d",
376 select->var_values[VAR_N],
377 select->var_values[VAR_PTS],
378 select->var_values[VAR_T],
379 !!(frame->flags & AV_FRAME_FLAG_KEY));
381 switch (inlink->type) {
382 case AVMEDIA_TYPE_VIDEO:
383 av_log(inlink->dst, AV_LOG_DEBUG, " interlace_type:%c pict_type:%c scene:%f",
384 !(frame->flags & AV_FRAME_FLAG_INTERLACED) ? 'P' :
385 (frame->flags & AV_FRAME_FLAG_TOP_FIELD_FIRST) ? 'T' : 'B',
386 av_get_picture_type_char(frame->pict_type),
387 select->var_values[VAR_SCENE]);
389 case AVMEDIA_TYPE_AUDIO:
390 av_log(inlink->dst, AV_LOG_DEBUG, " samples_n:%d consumed_samples_n:%f",
392 select->var_values[VAR_CONSUMED_SAMPLES_N]);
397 select->select_out = -1; /* drop */
398 } else if (isnan(res) || res < 0) {
399 select->select_out = 0; /* first output */
401 select->select_out = FFMIN(ceilf(res)-1, select->nb_outputs-1); /* other outputs */
404 av_log(inlink->dst, AV_LOG_DEBUG, " -> select:%f select_out:%d\n", res, select->select_out);
407 select->var_values[VAR_PREV_SELECTED_N] = select->var_values[VAR_N];
408 select->var_values[VAR_PREV_SELECTED_PTS] = select->var_values[VAR_PTS];
409 select->var_values[VAR_PREV_SELECTED_T] = select->var_values[VAR_T];
410 select->var_values[VAR_SELECTED_N] += 1.0;
411 if (inlink->type == AVMEDIA_TYPE_AUDIO)
412 select->var_values[VAR_CONSUMED_SAMPLES_N] += frame->nb_samples;
415 select->var_values[VAR_PREV_PTS] = select->var_values[VAR_PTS];
416 select->var_values[VAR_PREV_T] = select->var_values[VAR_T];
419 static int filter_frame(AVFilterLink *inlink, AVFrame *frame)
421 AVFilterContext *ctx = inlink->dst;
422 SelectContext *select = ctx->priv;
424 select_frame(ctx, frame);
426 return ff_filter_frame(ctx->outputs[select->select_out], frame);
428 av_frame_free(&frame);
432 static int request_frame(AVFilterLink *outlink)
434 AVFilterLink *inlink = outlink->src->inputs[0];
435 int ret = ff_request_frame(inlink);
439 static av_cold void uninit(AVFilterContext *ctx)
441 SelectContext *select = ctx->priv;
443 av_expr_free(select->expr);
446 if (select->do_scene_detect) {
447 av_frame_free(&select->prev_picref);
451 #if CONFIG_ASELECT_FILTER
453 DEFINE_OPTIONS(aselect, AV_OPT_FLAG_AUDIO_PARAM|AV_OPT_FLAG_FILTERING_PARAM);
454 AVFILTER_DEFINE_CLASS(aselect);
456 static av_cold int aselect_init(AVFilterContext *ctx)
458 SelectContext *select = ctx->priv;
461 if ((ret = init(ctx)) < 0)
464 if (select->do_scene_detect) {
465 av_log(ctx, AV_LOG_ERROR, "Scene detection is ignored in aselect filter\n");
466 return AVERROR(EINVAL);
472 static const AVFilterPad avfilter_af_aselect_inputs[] = {
475 .type = AVMEDIA_TYPE_AUDIO,
476 .config_props = config_input,
477 .filter_frame = filter_frame,
481 const AVFilter ff_af_aselect = {
483 .description = NULL_IF_CONFIG_SMALL("Select audio frames to pass in output."),
484 .init = aselect_init,
486 .priv_size = sizeof(SelectContext),
487 FILTER_INPUTS(avfilter_af_aselect_inputs),
488 .priv_class = &aselect_class,
489 .flags = AVFILTER_FLAG_DYNAMIC_OUTPUTS,
491 #endif /* CONFIG_ASELECT_FILTER */
493 #if CONFIG_SELECT_FILTER
495 static int query_formats(AVFilterContext *ctx)
497 SelectContext *select = ctx->priv;
499 if (!select->do_scene_detect) {
500 return ff_default_query_formats(ctx);
502 static const enum AVPixelFormat pix_fmts[] = {
503 AV_PIX_FMT_RGB24, AV_PIX_FMT_BGR24, AV_PIX_FMT_RGBA,
504 AV_PIX_FMT_ABGR, AV_PIX_FMT_BGRA, AV_PIX_FMT_GRAY8,
505 AV_PIX_FMT_YUV420P, AV_PIX_FMT_YUVJ420P,
506 AV_PIX_FMT_YUV422P, AV_PIX_FMT_YUVJ422P,
507 AV_PIX_FMT_YUV420P10,
510 return ff_set_common_formats_from_list(ctx, pix_fmts);
514 DEFINE_OPTIONS(select, AV_OPT_FLAG_VIDEO_PARAM|AV_OPT_FLAG_FILTERING_PARAM);
515 AVFILTER_DEFINE_CLASS(select);
517 static av_cold int select_init(AVFilterContext *ctx)
521 if ((ret = init(ctx)) < 0)
527 static const AVFilterPad avfilter_vf_select_inputs[] = {
530 .type = AVMEDIA_TYPE_VIDEO,
531 .config_props = config_input,
532 .filter_frame = filter_frame,
536 const AVFilter ff_vf_select = {
538 .description = NULL_IF_CONFIG_SMALL("Select video frames to pass in output."),
541 .priv_size = sizeof(SelectContext),
542 .priv_class = &select_class,
543 FILTER_INPUTS(avfilter_vf_select_inputs),
544 FILTER_QUERY_FUNC(query_formats),
545 .flags = AVFILTER_FLAG_DYNAMIC_OUTPUTS | AVFILTER_FLAG_METADATA_ONLY,
547 #endif /* CONFIG_SELECT_FILTER */