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vf_fps.c
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1 /*
2  * Copyright 2007 Bobby Bingham
3  * Copyright 2012 Robert Nagy <ronag89 gmail com>
4  * Copyright 2012 Anton Khirnov <anton khirnov net>
5  *
6  * This file is part of FFmpeg.
7  *
8  * FFmpeg is free software; you can redistribute it and/or
9  * modify it under the terms of the GNU Lesser General Public
10  * License as published by the Free Software Foundation; either
11  * version 2.1 of the License, or (at your option) any later version.
12  *
13  * FFmpeg is distributed in the hope that it will be useful,
14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16  * Lesser General Public License for more details.
17  *
18  * You should have received a copy of the GNU Lesser General Public
19  * License along with FFmpeg; if not, write to the Free Software
20  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
21  */
22 
23 /**
24  * @file
25  * a filter enforcing given constant framerate
26  */
27 
28 #include <float.h>
29 #include <stdint.h>
30 
31 #include "libavutil/common.h"
32 #include "libavutil/fifo.h"
33 #include "libavutil/mathematics.h"
34 #include "libavutil/opt.h"
35 #include "libavutil/parseutils.h"
36 
37 #define FF_INTERNAL_FIELDS 1
38 #include "framequeue.h"
39 #include "avfilter.h"
40 #include "internal.h"
41 #include "video.h"
42 
43 enum EOFAction {
47 };
48 
49 typedef struct FPSContext {
50  const AVClass *class;
51 
52  AVFifoBuffer *fifo; ///< store frames until we get two successive timestamps
53 
54  /* timestamps in input timebase */
55  int64_t first_pts; ///< pts of the first frame that arrived on this filter
56 
57  double start_time; ///< pts, in seconds, of the expected first frame
58 
59  AVRational framerate; ///< target framerate
60  int rounding; ///< AVRounding method for timestamps
61  int eof_action; ///< action performed for last frame in FIFO
62 
63  /* statistics */
64  int frames_in; ///< number of frames on input
65  int frames_out; ///< number of frames on output
66  int dup; ///< number of frames duplicated
67  int drop; ///< number of framed dropped
68 } FPSContext;
69 
70 #define OFFSET(x) offsetof(FPSContext, x)
71 #define V AV_OPT_FLAG_VIDEO_PARAM
72 #define F AV_OPT_FLAG_FILTERING_PARAM
73 static const AVOption fps_options[] = {
74  { "fps", "A string describing desired output framerate", OFFSET(framerate), AV_OPT_TYPE_VIDEO_RATE, { .str = "25" }, 0, INT_MAX, V|F },
75  { "start_time", "Assume the first PTS should be this value.", OFFSET(start_time), AV_OPT_TYPE_DOUBLE, { .dbl = DBL_MAX}, -DBL_MAX, DBL_MAX, V|F },
76  { "round", "set rounding method for timestamps", OFFSET(rounding), AV_OPT_TYPE_INT, { .i64 = AV_ROUND_NEAR_INF }, 0, 5, V|F, "round" },
77  { "zero", "round towards 0", 0, AV_OPT_TYPE_CONST, { .i64 = AV_ROUND_ZERO }, 0, 0, V|F, "round" },
78  { "inf", "round away from 0", 0, AV_OPT_TYPE_CONST, { .i64 = AV_ROUND_INF }, 0, 0, V|F, "round" },
79  { "down", "round towards -infty", 0, AV_OPT_TYPE_CONST, { .i64 = AV_ROUND_DOWN }, 0, 0, V|F, "round" },
80  { "up", "round towards +infty", 0, AV_OPT_TYPE_CONST, { .i64 = AV_ROUND_UP }, 0, 0, V|F, "round" },
81  { "near", "round to nearest", 0, AV_OPT_TYPE_CONST, { .i64 = AV_ROUND_NEAR_INF }, 0, 0, V|F, "round" },
82  { "eof_action", "action performed for last frame", OFFSET(eof_action), AV_OPT_TYPE_INT, { .i64 = EOF_ACTION_ROUND }, 0, EOF_ACTION_NB-1, V|F, "eof_action" },
83  { "round", "round similar to other frames", 0, AV_OPT_TYPE_CONST, { .i64 = EOF_ACTION_ROUND }, 0, 0, V|F, "eof_action" },
84  { "pass", "pass through last frame", 0, AV_OPT_TYPE_CONST, { .i64 = EOF_ACTION_PASS }, 0, 0, V|F, "eof_action" },
85  { NULL }
86 };
87 
89 
91 {
92  FPSContext *s = ctx->priv;
93 
94  if (!(s->fifo = av_fifo_alloc_array(2, sizeof(AVFrame*))))
95  return AVERROR(ENOMEM);
96 
98 
99  av_log(ctx, AV_LOG_VERBOSE, "fps=%d/%d\n", s->framerate.num, s->framerate.den);
100  return 0;
101 }
102 
103 static void flush_fifo(AVFifoBuffer *fifo)
104 {
105  while (av_fifo_size(fifo)) {
106  AVFrame *tmp;
107  av_fifo_generic_read(fifo, &tmp, sizeof(tmp), NULL);
108  av_frame_free(&tmp);
109  }
110 }
111 
113 {
114  FPSContext *s = ctx->priv;
115  if (s->fifo) {
116  s->drop += av_fifo_size(s->fifo) / sizeof(AVFrame*);
117  flush_fifo(s->fifo);
118  av_fifo_freep(&s->fifo);
119  }
120 
121  av_log(ctx, AV_LOG_VERBOSE, "%d frames in, %d frames out; %d frames dropped, "
122  "%d frames duplicated.\n", s->frames_in, s->frames_out, s->drop, s->dup);
123 }
124 
125 static int config_props(AVFilterLink* link)
126 {
127  FPSContext *s = link->src->priv;
128 
129  link->time_base = av_inv_q(s->framerate);
130  link->frame_rate= s->framerate;
131  link->w = link->src->inputs[0]->w;
132  link->h = link->src->inputs[0]->h;
133 
134  return 0;
135 }
136 
137 static int request_frame(AVFilterLink *outlink)
138 {
139  AVFilterContext *ctx = outlink->src;
140  FPSContext *s = ctx->priv;
141  int ret;
142 
143  ret = ff_request_frame(ctx->inputs[0]);
144 
145  /* flush the fifo */
146  if (ret == AVERROR_EOF && av_fifo_size(s->fifo)) {
147  int i;
148  for (i = 0; av_fifo_size(s->fifo); i++) {
149  AVFrame *buf;
150 
151  av_fifo_generic_read(s->fifo, &buf, sizeof(buf), NULL);
152  if (av_fifo_size(s->fifo)) {
153  buf->pts = av_rescale_q(s->first_pts, ctx->inputs[0]->time_base,
154  outlink->time_base) + s->frames_out;
155 
156  if ((ret = ff_filter_frame(outlink, buf)) < 0)
157  return ret;
158 
159  s->frames_out++;
160  } else {
161  /* This is the last frame, we may have to duplicate it to match
162  * the last frame duration */
163  int j;
164  int eof_rounding = (s->eof_action == EOF_ACTION_PASS) ? AV_ROUND_UP : s->rounding;
165  int delta = av_rescale_q_rnd(ctx->inputs[0]->current_pts - s->first_pts,
166  ctx->inputs[0]->time_base,
167  outlink->time_base, eof_rounding) - s->frames_out;
168  av_log(ctx, AV_LOG_DEBUG, "EOF frames_out:%d delta:%d\n", s->frames_out, delta);
169  /* if the delta is equal to 1, it means we just need to output
170  * the last frame. Greater than 1 means we will need duplicate
171  * delta-1 frames */
172  if (delta > 0 ) {
173  for (j = 0; j < delta; j++) {
174  AVFrame *dup = av_frame_clone(buf);
175 
176  av_log(ctx, AV_LOG_DEBUG, "Duplicating frame.\n");
177  dup->pts = av_rescale_q(s->first_pts, ctx->inputs[0]->time_base,
178  outlink->time_base) + s->frames_out;
179 
180  if ((ret = ff_filter_frame(outlink, dup)) < 0)
181  return ret;
182 
183  s->frames_out++;
184  if (j > 0) s->dup++;
185  }
186  av_frame_free(&buf);
187  } else {
188  /* for delta less or equal to 0, we should drop the frame,
189  * otherwise, we will have one or more extra frames */
190  av_frame_free(&buf);
191  s->drop++;
192  }
193  }
194  }
195  return 0;
196  }
197 
198  return ret;
199 }
200 
202 {
203  int ret;
204 
205  if (!av_fifo_space(fifo) &&
206  (ret = av_fifo_realloc2(fifo, 2*av_fifo_size(fifo)))) {
207  av_frame_free(&buf);
208  return ret;
209  }
210 
211  av_fifo_generic_write(fifo, &buf, sizeof(buf), NULL);
212  return 0;
213 }
214 
215 static int filter_frame(AVFilterLink *inlink, AVFrame *buf)
216 {
217  AVFilterContext *ctx = inlink->dst;
218  FPSContext *s = ctx->priv;
219  AVFilterLink *outlink = ctx->outputs[0];
220  int64_t delta;
221  int i, ret;
222 
223  s->frames_in++;
224  /* discard frames until we get the first timestamp */
225  if (s->first_pts == AV_NOPTS_VALUE) {
226  if (buf->pts != AV_NOPTS_VALUE) {
227  ret = write_to_fifo(s->fifo, buf);
228  if (ret < 0)
229  return ret;
230 
231  if (s->start_time != DBL_MAX && s->start_time != AV_NOPTS_VALUE) {
232  double first_pts = s->start_time * AV_TIME_BASE;
233  first_pts = FFMIN(FFMAX(first_pts, INT64_MIN), INT64_MAX);
234  s->first_pts = av_rescale_q(first_pts, AV_TIME_BASE_Q,
235  inlink->time_base);
236  av_log(ctx, AV_LOG_VERBOSE, "Set first pts to (in:%"PRId64" out:%"PRId64")\n",
237  s->first_pts, av_rescale_q(first_pts, AV_TIME_BASE_Q,
238  outlink->time_base));
239  } else {
240  s->first_pts = buf->pts;
241  }
242  } else {
243  av_log(ctx, AV_LOG_WARNING, "Discarding initial frame(s) with no "
244  "timestamp.\n");
245  av_frame_free(&buf);
246  s->drop++;
247  }
248  return 0;
249  }
250 
251  /* now wait for the next timestamp */
252  if (buf->pts == AV_NOPTS_VALUE || av_fifo_size(s->fifo) <= 0) {
253  return write_to_fifo(s->fifo, buf);
254  }
255 
256  /* number of output frames */
257  delta = av_rescale_q_rnd(buf->pts - s->first_pts, inlink->time_base,
258  outlink->time_base, s->rounding) - s->frames_out ;
259 
260  if (delta < 1) {
261  /* drop everything buffered except the last */
262  int drop = av_fifo_size(s->fifo)/sizeof(AVFrame*);
263 
264  av_log(ctx, AV_LOG_DEBUG, "Dropping %d frame(s).\n", drop);
265  s->drop += drop;
266 
267  flush_fifo(s->fifo);
268  ret = write_to_fifo(s->fifo, buf);
269 
270  return ret;
271  }
272 
273  /* can output >= 1 frames */
274  for (i = 0; i < delta; i++) {
275  AVFrame *buf_out;
276  av_fifo_generic_read(s->fifo, &buf_out, sizeof(buf_out), NULL);
277 
278  /* duplicate the frame if needed */
279  if (!av_fifo_size(s->fifo) && i < delta - 1) {
280  AVFrame *dup = av_frame_clone(buf_out);
281 
282  av_log(ctx, AV_LOG_DEBUG, "Duplicating frame.\n");
283  if (dup)
284  ret = write_to_fifo(s->fifo, dup);
285  else
286  ret = AVERROR(ENOMEM);
287 
288  if (ret < 0) {
289  av_frame_free(&buf_out);
290  av_frame_free(&buf);
291  return ret;
292  }
293 
294  s->dup++;
295  }
296 
297  buf_out->pts = av_rescale_q(s->first_pts, inlink->time_base,
298  outlink->time_base) + s->frames_out;
299 
300  if ((ret = ff_filter_frame(outlink, buf_out)) < 0) {
301  av_frame_free(&buf);
302  return ret;
303  }
304 
305  s->frames_out++;
306  }
307  flush_fifo(s->fifo);
308 
309  ret = write_to_fifo(s->fifo, buf);
310 
311  return ret;
312 }
313 
315  {
316  .name = "default",
317  .type = AVMEDIA_TYPE_VIDEO,
318  .filter_frame = filter_frame,
319  },
320  { NULL }
321 };
322 
324  {
325  .name = "default",
326  .type = AVMEDIA_TYPE_VIDEO,
327  .request_frame = request_frame,
328  .config_props = config_props
329  },
330  { NULL }
331 };
332 
334  .name = "fps",
335  .description = NULL_IF_CONFIG_SMALL("Force constant framerate."),
336  .init = init,
337  .uninit = uninit,
338  .priv_size = sizeof(FPSContext),
339  .priv_class = &fps_class,
340  .inputs = avfilter_vf_fps_inputs,
341  .outputs = avfilter_vf_fps_outputs,
342 };
int frames_out
number of frames on output
Definition: vf_fps.c:65
#define NULL
Definition: coverity.c:32
#define F
Definition: vf_fps.c:72
const char * s
Definition: avisynth_c.h:768
AVFifoBuffer * fifo
store frames until we get two successive timestamps
Definition: vf_fps.c:52
AVFilter ff_vf_fps
Definition: vf_fps.c:333
static const AVOption fps_options[]
Definition: vf_fps.c:73
This structure describes decoded (raw) audio or video data.
Definition: frame.h:201
AVOption.
Definition: opt.h:246
#define AV_LOG_WARNING
Something somehow does not look correct.
Definition: log.h:182
Main libavfilter public API header.
int num
Numerator.
Definition: rational.h:59
EOFAction
Definition: framesync.h:26
int drop
number of framed dropped
Definition: vf_fps.c:67
int64_t first_pts
pts of the first frame that arrived on this filter
Definition: vf_fps.c:55
int av_fifo_generic_write(AVFifoBuffer *f, void *src, int size, int(*func)(void *, void *, int))
Feed data from a user-supplied callback to an AVFifoBuffer.
Definition: fifo.c:122
const char * name
Pad name.
Definition: internal.h:60
AVFilterLink ** inputs
array of pointers to input links
Definition: avfilter.h:346
int ff_filter_frame(AVFilterLink *link, AVFrame *frame)
Send a frame of data to the next filter.
Definition: avfilter.c:1113
static int64_t start_time
Definition: ffplay.c:327
Round toward +infinity.
Definition: mathematics.h:83
#define av_cold
Definition: attributes.h:82
int frames_in
number of frames on input
Definition: vf_fps.c:64
float delta
AVOptions.
int64_t pts
Presentation timestamp in time_base units (time when frame should be shown to user).
Definition: frame.h:294
int av_fifo_space(const AVFifoBuffer *f)
Return the amount of space in bytes in the AVFifoBuffer, that is the amount of data you can write int...
Definition: fifo.c:82
#define AVERROR_EOF
End of file.
Definition: error.h:55
static av_cold int init(AVFilterContext *ctx)
Definition: vf_fps.c:90
#define AV_LOG_VERBOSE
Detailed information.
Definition: log.h:192
#define av_log(a,...)
A filter pad used for either input or output.
Definition: internal.h:54
int64_t av_rescale_q(int64_t a, AVRational bq, AVRational cq)
Rescale a 64-bit integer by 2 rational numbers.
Definition: mathematics.c:142
int dup
number of frames duplicated
Definition: vf_fps.c:66
int eof_action
action performed for last frame in FIFO
Definition: vf_fps.c:61
static av_cold void uninit(AVFilterContext *ctx)
Definition: vf_fps.c:112
#define AVERROR(e)
Definition: error.h:43
Round away from zero.
Definition: mathematics.h:81
void av_frame_free(AVFrame **frame)
Free the frame and any dynamically allocated objects in it, e.g.
Definition: frame.c:163
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:186
void * priv
private data for use by the filter
Definition: avfilter.h:353
#define AV_LOG_DEBUG
Stuff which is only useful for libav* developers.
Definition: log.h:197
int av_fifo_generic_read(AVFifoBuffer *f, void *dest, int buf_size, void(*func)(void *, void *, int))
Feed data from an AVFifoBuffer to a user-supplied callback.
Definition: fifo.c:213
static const AVFilterPad avfilter_vf_fps_inputs[]
Definition: vf_fps.c:314
Round to nearest and halfway cases away from zero.
Definition: mathematics.h:84
static int request_frame(AVFilterLink *outlink)
Definition: vf_fps.c:137
#define V
Definition: vf_fps.c:71
static const AVFilterPad avfilter_vf_fps_outputs[]
Definition: vf_fps.c:323
#define FFMAX(a, b)
Definition: common.h:94
#define OFFSET(x)
Definition: vf_fps.c:70
#define AV_TIME_BASE
Internal time base represented as integer.
Definition: avutil.h:254
#define FFMIN(a, b)
Definition: common.h:96
Round toward zero.
Definition: mathematics.h:80
AVFormatContext * ctx
Definition: movenc.c:48
static int filter_frame(AVFilterLink *inlink, AVFrame *buf)
Definition: vf_fps.c:215
static const AVFilterPad inputs[]
Definition: af_acontrast.c:193
AVFrame * av_frame_clone(const AVFrame *src)
Create a new frame that references the same data as src.
Definition: frame.c:497
static const AVFilterPad outputs[]
Definition: af_acontrast.c:203
int av_fifo_size(const AVFifoBuffer *f)
Return the amount of data in bytes in the AVFifoBuffer, that is the amount of data you can read from ...
Definition: fifo.c:77
#define AV_TIME_BASE_Q
Internal time base represented as fractional value.
Definition: avutil.h:260
int av_fifo_realloc2(AVFifoBuffer *f, unsigned int new_size)
Resize an AVFifoBuffer.
Definition: fifo.c:87
a very simple circular buffer FIFO implementation
void * buf
Definition: avisynth_c.h:690
Describe the class of an AVClass context structure.
Definition: log.h:67
Filter definition.
Definition: avfilter.h:144
Rational number (pair of numerator and denominator).
Definition: rational.h:58
offset must point to AVRational
Definition: opt.h:236
const char * name
Filter name.
Definition: avfilter.h:148
misc parsing utilities
AVFilterLink ** outputs
array of pointers to output links
Definition: avfilter.h:350
Round toward -infinity.
Definition: mathematics.h:82
AVFifoBuffer * av_fifo_alloc_array(size_t nmemb, size_t size)
Initialize an AVFifoBuffer.
Definition: fifo.c:49
AVFILTER_DEFINE_CLASS(fps)
static av_always_inline AVRational av_inv_q(AVRational q)
Invert a rational.
Definition: rational.h:159
common internal and external API header
AVRational framerate
target framerate
Definition: vf_fps.c:59
int den
Denominator.
Definition: rational.h:60
int rounding
AVRounding method for timestamps.
Definition: vf_fps.c:60
static int config_props(AVFilterLink *link)
Definition: vf_fps.c:125
static int write_to_fifo(AVFifoBuffer *fifo, AVFrame *buf)
Definition: vf_fps.c:201
An instance of a filter.
Definition: avfilter.h:338
void av_fifo_freep(AVFifoBuffer **f)
Free an AVFifoBuffer and reset pointer to NULL.
Definition: fifo.c:63
int64_t av_rescale_q_rnd(int64_t a, AVRational bq, AVRational cq, enum AVRounding rnd)
Rescale a 64-bit integer by 2 rational numbers with specified rounding.
Definition: mathematics.c:134
int ff_request_frame(AVFilterLink *link)
Request an input frame from the filter at the other end of the link.
Definition: avfilter.c:405
internal API functions
static void flush_fifo(AVFifoBuffer *fifo)
Definition: vf_fps.c:103
double start_time
pts, in seconds, of the expected first frame
Definition: vf_fps.c:57
#define AV_NOPTS_VALUE
Undefined timestamp value.
Definition: avutil.h:248
static uint8_t tmp[11]
Definition: aes_ctr.c:26