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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 typedef struct FPSContext {
44  const AVClass *class;
45 
46  AVFifoBuffer *fifo; ///< store frames until we get two successive timestamps
47 
48  /* timestamps in input timebase */
49  int64_t first_pts; ///< pts of the first frame that arrived on this filter
50 
51  double start_time; ///< pts, in seconds, of the expected first frame
52 
53  AVRational framerate; ///< target framerate
54  int rounding; ///< AVRounding method for timestamps
55 
56  /* statistics */
57  int frames_in; ///< number of frames on input
58  int frames_out; ///< number of frames on output
59  int dup; ///< number of frames duplicated
60  int drop; ///< number of framed dropped
61 } FPSContext;
62 
63 #define OFFSET(x) offsetof(FPSContext, x)
64 #define V AV_OPT_FLAG_VIDEO_PARAM
65 #define F AV_OPT_FLAG_FILTERING_PARAM
66 static const AVOption fps_options[] = {
67  { "fps", "A string describing desired output framerate", OFFSET(framerate), AV_OPT_TYPE_VIDEO_RATE, { .str = "25" }, 0, INT_MAX, V|F },
68  { "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 },
69  { "round", "set rounding method for timestamps", OFFSET(rounding), AV_OPT_TYPE_INT, { .i64 = AV_ROUND_NEAR_INF }, 0, 5, V|F, "round" },
70  { "zero", "round towards 0", OFFSET(rounding), AV_OPT_TYPE_CONST, { .i64 = AV_ROUND_ZERO }, 0, 5, V|F, "round" },
71  { "inf", "round away from 0", OFFSET(rounding), AV_OPT_TYPE_CONST, { .i64 = AV_ROUND_INF }, 0, 5, V|F, "round" },
72  { "down", "round towards -infty", OFFSET(rounding), AV_OPT_TYPE_CONST, { .i64 = AV_ROUND_DOWN }, 0, 5, V|F, "round" },
73  { "up", "round towards +infty", OFFSET(rounding), AV_OPT_TYPE_CONST, { .i64 = AV_ROUND_UP }, 0, 5, V|F, "round" },
74  { "near", "round to nearest", OFFSET(rounding), AV_OPT_TYPE_CONST, { .i64 = AV_ROUND_NEAR_INF }, 0, 5, V|F, "round" },
75  { NULL }
76 };
77 
79 
81 {
82  FPSContext *s = ctx->priv;
83 
84  if (!(s->fifo = av_fifo_alloc_array(2, sizeof(AVFrame*))))
85  return AVERROR(ENOMEM);
86 
88 
89  av_log(ctx, AV_LOG_VERBOSE, "fps=%d/%d\n", s->framerate.num, s->framerate.den);
90  return 0;
91 }
92 
93 static void flush_fifo(AVFifoBuffer *fifo)
94 {
95  while (av_fifo_size(fifo)) {
96  AVFrame *tmp;
97  av_fifo_generic_read(fifo, &tmp, sizeof(tmp), NULL);
98  av_frame_free(&tmp);
99  }
100 }
101 
103 {
104  FPSContext *s = ctx->priv;
105  if (s->fifo) {
106  s->drop += av_fifo_size(s->fifo) / sizeof(AVFrame*);
107  flush_fifo(s->fifo);
108  av_fifo_freep(&s->fifo);
109  }
110 
111  av_log(ctx, AV_LOG_VERBOSE, "%d frames in, %d frames out; %d frames dropped, "
112  "%d frames duplicated.\n", s->frames_in, s->frames_out, s->drop, s->dup);
113 }
114 
115 static int config_props(AVFilterLink* link)
116 {
117  FPSContext *s = link->src->priv;
118 
119  link->time_base = av_inv_q(s->framerate);
120  link->frame_rate= s->framerate;
121  link->w = link->src->inputs[0]->w;
122  link->h = link->src->inputs[0]->h;
123 
124  return 0;
125 }
126 
127 static int request_frame(AVFilterLink *outlink)
128 {
129  AVFilterContext *ctx = outlink->src;
130  FPSContext *s = ctx->priv;
131  int ret;
132 
133  ret = ff_request_frame(ctx->inputs[0]);
134 
135  /* flush the fifo */
136  if (ret == AVERROR_EOF && av_fifo_size(s->fifo)) {
137  int i;
138  for (i = 0; av_fifo_size(s->fifo); i++) {
139  AVFrame *buf;
140 
141  av_fifo_generic_read(s->fifo, &buf, sizeof(buf), NULL);
142  if (av_fifo_size(s->fifo)) {
143  buf->pts = av_rescale_q(s->first_pts, ctx->inputs[0]->time_base,
144  outlink->time_base) + s->frames_out;
145 
146  if ((ret = ff_filter_frame(outlink, buf)) < 0)
147  return ret;
148 
149  s->frames_out++;
150  } else {
151  /* This is the last frame, we may have to duplicate it to match
152  * the last frame duration */
153  int j;
154  int delta = av_rescale_q_rnd(ctx->inputs[0]->current_pts - s->first_pts,
155  ctx->inputs[0]->time_base,
156  outlink->time_base, s->rounding) - s->frames_out ;
157  /* if the delta is equal to 1, it means we just need to output
158  * the last frame. Greater than 1 means we will need duplicate
159  * delta-1 frames */
160  if (delta > 0 ) {
161  for (j = 0; j < delta; j++) {
162  AVFrame *dup = av_frame_clone(buf);
163 
164  av_log(ctx, AV_LOG_DEBUG, "Duplicating frame.\n");
165  dup->pts = av_rescale_q(s->first_pts, ctx->inputs[0]->time_base,
166  outlink->time_base) + s->frames_out;
167 
168  if ((ret = ff_filter_frame(outlink, dup)) < 0)
169  return ret;
170 
171  s->frames_out++;
172  if (j > 0) s->dup++;
173  }
174  av_frame_free(&buf);
175  } else {
176  /* for delta less or equal to 0, we should drop the frame,
177  * otherwise, we will have one or more extra frames */
178  av_frame_free(&buf);
179  s->drop++;
180  }
181  }
182  }
183  return 0;
184  }
185 
186  return ret;
187 }
188 
190 {
191  int ret;
192 
193  if (!av_fifo_space(fifo) &&
194  (ret = av_fifo_realloc2(fifo, 2*av_fifo_size(fifo)))) {
195  av_frame_free(&buf);
196  return ret;
197  }
198 
199  av_fifo_generic_write(fifo, &buf, sizeof(buf), NULL);
200  return 0;
201 }
202 
203 static int filter_frame(AVFilterLink *inlink, AVFrame *buf)
204 {
205  AVFilterContext *ctx = inlink->dst;
206  FPSContext *s = ctx->priv;
207  AVFilterLink *outlink = ctx->outputs[0];
208  int64_t delta;
209  int i, ret;
210 
211  s->frames_in++;
212  /* discard frames until we get the first timestamp */
213  if (s->first_pts == AV_NOPTS_VALUE) {
214  if (buf->pts != AV_NOPTS_VALUE) {
215  ret = write_to_fifo(s->fifo, buf);
216  if (ret < 0)
217  return ret;
218 
219  if (s->start_time != DBL_MAX && s->start_time != AV_NOPTS_VALUE) {
220  double first_pts = s->start_time * AV_TIME_BASE;
221  first_pts = FFMIN(FFMAX(first_pts, INT64_MIN), INT64_MAX);
222  s->first_pts = av_rescale_q(first_pts, AV_TIME_BASE_Q,
223  inlink->time_base);
224  av_log(ctx, AV_LOG_VERBOSE, "Set first pts to (in:%"PRId64" out:%"PRId64")\n",
225  s->first_pts, av_rescale_q(first_pts, AV_TIME_BASE_Q,
226  outlink->time_base));
227  } else {
228  s->first_pts = buf->pts;
229  }
230  } else {
231  av_log(ctx, AV_LOG_WARNING, "Discarding initial frame(s) with no "
232  "timestamp.\n");
233  av_frame_free(&buf);
234  s->drop++;
235  }
236  return 0;
237  }
238 
239  /* now wait for the next timestamp */
240  if (buf->pts == AV_NOPTS_VALUE || av_fifo_size(s->fifo) <= 0) {
241  return write_to_fifo(s->fifo, buf);
242  }
243 
244  /* number of output frames */
245  delta = av_rescale_q_rnd(buf->pts - s->first_pts, inlink->time_base,
246  outlink->time_base, s->rounding) - s->frames_out ;
247 
248  if (delta < 1) {
249  /* drop everything buffered except the last */
250  int drop = av_fifo_size(s->fifo)/sizeof(AVFrame*);
251 
252  av_log(ctx, AV_LOG_DEBUG, "Dropping %d frame(s).\n", drop);
253  s->drop += drop;
254 
255  flush_fifo(s->fifo);
256  ret = write_to_fifo(s->fifo, buf);
257 
258  return ret;
259  }
260 
261  /* can output >= 1 frames */
262  for (i = 0; i < delta; i++) {
263  AVFrame *buf_out;
264  av_fifo_generic_read(s->fifo, &buf_out, sizeof(buf_out), NULL);
265 
266  /* duplicate the frame if needed */
267  if (!av_fifo_size(s->fifo) && i < delta - 1) {
268  AVFrame *dup = av_frame_clone(buf_out);
269 
270  av_log(ctx, AV_LOG_DEBUG, "Duplicating frame.\n");
271  if (dup)
272  ret = write_to_fifo(s->fifo, dup);
273  else
274  ret = AVERROR(ENOMEM);
275 
276  if (ret < 0) {
277  av_frame_free(&buf_out);
278  av_frame_free(&buf);
279  return ret;
280  }
281 
282  s->dup++;
283  }
284 
285  buf_out->pts = av_rescale_q(s->first_pts, inlink->time_base,
286  outlink->time_base) + s->frames_out;
287 
288  if ((ret = ff_filter_frame(outlink, buf_out)) < 0) {
289  av_frame_free(&buf);
290  return ret;
291  }
292 
293  s->frames_out++;
294  }
295  flush_fifo(s->fifo);
296 
297  ret = write_to_fifo(s->fifo, buf);
298 
299  return ret;
300 }
301 
303  {
304  .name = "default",
305  .type = AVMEDIA_TYPE_VIDEO,
306  .filter_frame = filter_frame,
307  },
308  { NULL }
309 };
310 
312  {
313  .name = "default",
314  .type = AVMEDIA_TYPE_VIDEO,
315  .request_frame = request_frame,
316  .config_props = config_props
317  },
318  { NULL }
319 };
320 
322  .name = "fps",
323  .description = NULL_IF_CONFIG_SMALL("Force constant framerate."),
324  .init = init,
325  .uninit = uninit,
326  .priv_size = sizeof(FPSContext),
327  .priv_class = &fps_class,
328  .inputs = avfilter_vf_fps_inputs,
329  .outputs = avfilter_vf_fps_outputs,
330 };
int frames_out
number of frames on output
Definition: vf_fps.c:58
#define NULL
Definition: coverity.c:32
#define F
Definition: vf_fps.c:65
const char * s
Definition: avisynth_c.h:768
AVFifoBuffer * fifo
store frames until we get two successive timestamps
Definition: vf_fps.c:46
AVFilter ff_vf_fps
Definition: vf_fps.c:321
static const AVOption fps_options[]
Definition: vf_fps.c:66
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
int drop
number of framed dropped
Definition: vf_fps.c:60
int64_t first_pts
pts of the first frame that arrived on this filter
Definition: vf_fps.c:49
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:1151
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:57
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:80
#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:59
static av_cold void uninit(AVFilterContext *ctx)
Definition: vf_fps.c:102
#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:179
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:302
Round to nearest and halfway cases away from zero.
Definition: mathematics.h:84
static int request_frame(AVFilterLink *outlink)
Definition: vf_fps.c:127
#define V
Definition: vf_fps.c:64
static const AVFilterPad avfilter_vf_fps_outputs[]
Definition: vf_fps.c:311
#define FFMAX(a, b)
Definition: common.h:94
#define OFFSET(x)
Definition: vf_fps.c:63
#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:203
static const AVFilterPad outputs[]
Definition: af_afftfilt.c:389
AVFrame * av_frame_clone(const AVFrame *src)
Create a new frame that references the same data as src.
Definition: frame.c:489
static const AVFilterPad inputs[]
Definition: af_afftfilt.c:379
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:53
int den
Denominator.
Definition: rational.h:60
int rounding
AVRounding method for timestamps.
Definition: vf_fps.c:54
static int config_props(AVFilterLink *link)
Definition: vf_fps.c:115
static int write_to_fifo(AVFifoBuffer *fifo, AVFrame *buf)
Definition: vf_fps.c:189
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:93
double start_time
pts, in seconds, of the expected first frame
Definition: vf_fps.c:51
#define AV_NOPTS_VALUE
Undefined timestamp value.
Definition: avutil.h:248
static uint8_t tmp[11]
Definition: aes_ctr.c:26