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framesync.c
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1 /*
2  * Copyright (c) 2013 Nicolas George
3  *
4  * This file is part of FFmpeg.
5  *
6  * FFmpeg is free software; you can redistribute it and/or
7  * modify it under the terms of the GNU Lesser General Public License
8  * as published by the Free Software Foundation; either
9  * version 2.1 of the License, or (at your option) any later version.
10  *
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
14  * GNU Lesser General Public License for more details.
15  *
16  * You should have received a copy of the GNU Lesser General Public License
17  * along with FFmpeg; if not, write to the Free Software Foundation, Inc.,
18  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
19  */
20 
21 #include "libavutil/avassert.h"
22 #include "avfilter.h"
23 #include "bufferqueue.h"
24 #include "framesync.h"
25 #include "internal.h"
26 
27 #define OFFSET(member) offsetof(FFFrameSync, member)
28 
29 static const char *framesync_name(void *ptr)
30 {
31  return "framesync";
32 }
33 
34 static const AVClass framesync_class = {
36  .class_name = "framesync",
37  .item_name = framesync_name,
38  .category = AV_CLASS_CATEGORY_FILTER,
39  .option = NULL,
40  .parent_log_context_offset = OFFSET(parent),
41 };
42 
43 enum {
47 };
48 
49 void ff_framesync_init(FFFrameSync *fs, void *parent, unsigned nb_in)
50 {
51  fs->class = &framesync_class;
52  fs->parent = parent;
53  fs->nb_in = nb_in;
54 }
55 
57 {
58  unsigned i, level = 0;
59 
60  for (i = 0; i < fs->nb_in; i++)
61  if (fs->in[i].state != STATE_EOF)
62  level = FFMAX(level, fs->in[i].sync);
63  av_assert0(level <= fs->sync_level);
64  if (level < fs->sync_level)
65  av_log(fs, AV_LOG_VERBOSE, "Sync level %u\n", level);
66  if (level)
67  fs->sync_level = level;
68  else
69  fs->eof = 1;
70 }
71 
73 {
74  unsigned i;
75  int64_t gcd, lcm;
76 
77  if (!fs->time_base.num) {
78  for (i = 0; i < fs->nb_in; i++) {
79  if (fs->in[i].sync) {
80  if (fs->time_base.num) {
81  gcd = av_gcd(fs->time_base.den, fs->in[i].time_base.den);
82  lcm = (fs->time_base.den / gcd) * fs->in[i].time_base.den;
83  if (lcm < AV_TIME_BASE / 2) {
84  fs->time_base.den = lcm;
85  fs->time_base.num = av_gcd(fs->time_base.num,
86  fs->in[i].time_base.num);
87  } else {
88  fs->time_base.num = 1;
90  break;
91  }
92  } else {
93  fs->time_base = fs->in[i].time_base;
94  }
95  }
96  }
97  if (!fs->time_base.num) {
98  av_log(fs, AV_LOG_ERROR, "Impossible to set time base\n");
99  return AVERROR(EINVAL);
100  }
101  av_log(fs, AV_LOG_VERBOSE, "Selected %d/%d time base\n",
102  fs->time_base.num, fs->time_base.den);
103  }
104 
105  for (i = 0; i < fs->nb_in; i++)
106  fs->in[i].pts = fs->in[i].pts_next = AV_NOPTS_VALUE;
107  fs->sync_level = UINT_MAX;
109 
110  return 0;
111 }
112 
114 {
115  int latest;
116  unsigned i;
117  int64_t pts;
118 
119  if (fs->eof)
120  return;
121  while (!fs->frame_ready) {
122  latest = -1;
123  for (i = 0; i < fs->nb_in; i++) {
124  if (!fs->in[i].have_next) {
125  if (latest < 0 || fs->in[i].pts < fs->in[latest].pts)
126  latest = i;
127  }
128  }
129  if (latest >= 0) {
130  fs->in_request = latest;
131  break;
132  }
133 
134  pts = fs->in[0].pts_next;
135  for (i = 1; i < fs->nb_in; i++)
136  if (fs->in[i].pts_next < pts)
137  pts = fs->in[i].pts_next;
138  if (pts == INT64_MAX) {
139  fs->eof = 1;
140  break;
141  }
142  for (i = 0; i < fs->nb_in; i++) {
143  if (fs->in[i].pts_next == pts ||
144  (fs->in[i].before == EXT_INFINITY &&
145  fs->in[i].state == STATE_BOF)) {
146  av_frame_free(&fs->in[i].frame);
147  fs->in[i].frame = fs->in[i].frame_next;
148  fs->in[i].pts = fs->in[i].pts_next;
149  fs->in[i].frame_next = NULL;
150  fs->in[i].pts_next = AV_NOPTS_VALUE;
151  fs->in[i].have_next = 0;
152  fs->in[i].state = fs->in[i].frame ? STATE_RUN : STATE_EOF;
153  if (fs->in[i].sync == fs->sync_level && fs->in[i].frame)
154  fs->frame_ready = 1;
155  if (fs->in[i].state == STATE_EOF &&
156  fs->in[i].after == EXT_STOP)
157  fs->eof = 1;
158  }
159  }
160  if (fs->eof)
161  fs->frame_ready = 0;
162  if (fs->frame_ready)
163  for (i = 0; i < fs->nb_in; i++)
164  if ((fs->in[i].state == STATE_BOF &&
165  fs->in[i].before == EXT_STOP))
166  fs->frame_ready = 0;
167  fs->pts = pts;
168  }
169 }
170 
171 static int64_t framesync_pts_extrapolate(FFFrameSync *fs, unsigned in,
172  int64_t pts)
173 {
174  /* Possible enhancement: use the link's frame rate */
175  return pts + 1;
176 }
177 
178 static void framesync_inject_frame(FFFrameSync *fs, unsigned in, AVFrame *frame)
179 {
180  int64_t pts;
181 
182  av_assert0(!fs->in[in].have_next);
183  if (frame) {
184  pts = av_rescale_q(frame->pts, fs->in[in].time_base, fs->time_base);
185  frame->pts = pts;
186  } else {
187  pts = fs->in[in].state != STATE_RUN || fs->in[in].after == EXT_INFINITY
188  ? INT64_MAX : framesync_pts_extrapolate(fs, in, fs->in[in].pts);
189  fs->in[in].sync = 0;
191  }
192  fs->in[in].frame_next = frame;
193  fs->in[in].pts_next = pts;
194  fs->in[in].have_next = 1;
195 }
196 
198 {
199  av_assert1(in < fs->nb_in);
200  if (!fs->in[in].have_next)
201  framesync_inject_frame(fs, in, frame);
202  else
203  ff_bufqueue_add(fs, &fs->in[in].queue, frame);
204  return 0;
205 }
206 
208 {
209  unsigned i;
210 
211  av_assert0(!fs->frame_ready);
212  for (i = 0; i < fs->nb_in; i++)
213  if (!fs->in[i].have_next && fs->in[i].queue.available)
215  fs->frame_ready = 0;
216  framesync_advance(fs);
217 }
218 
220 {
221  fs->frame_ready = 0;
222 }
223 
224 int ff_framesync_get_frame(FFFrameSync *fs, unsigned in, AVFrame **rframe,
225  unsigned get)
226 {
227  AVFrame *frame;
228  unsigned need_copy = 0, i;
229  int64_t pts_next;
230  int ret;
231 
232  if (!fs->in[in].frame) {
233  *rframe = NULL;
234  return 0;
235  }
236  frame = fs->in[in].frame;
237  if (get) {
238  /* Find out if we need to copy the frame: is there another sync
239  stream, and do we know if its current frame will outlast this one? */
240  pts_next = fs->in[in].have_next ? fs->in[in].pts_next : INT64_MAX;
241  for (i = 0; i < fs->nb_in && !need_copy; i++)
242  if (i != in && fs->in[i].sync &&
243  (!fs->in[i].have_next || fs->in[i].pts_next < pts_next))
244  need_copy = 1;
245  if (need_copy) {
246  if (!(frame = av_frame_clone(frame)))
247  return AVERROR(ENOMEM);
248  if ((ret = av_frame_make_writable(frame)) < 0) {
249  av_frame_free(&frame);
250  return ret;
251  }
252  } else {
253  fs->in[in].frame = NULL;
254  }
255  fs->frame_ready = 0;
256  }
257  *rframe = frame;
258  return 0;
259 }
260 
262 {
263  unsigned i;
264 
265  for (i = 0; i < fs->nb_in; i++) {
266  av_frame_free(&fs->in[i].frame);
267  av_frame_free(&fs->in[i].frame_next);
269  }
270 }
271 
273 {
274  int ret, count = 0;
275 
276  av_assert0(fs->on_event);
277  while (1) {
278  ff_framesync_next(fs);
279  if (fs->eof || !fs->frame_ready)
280  break;
281  if ((ret = fs->on_event(fs)) < 0)
282  return ret;
283  ff_framesync_drop(fs);
284  count++;
285  if (!all)
286  break;
287  }
288  if (!count && fs->eof)
289  return AVERROR_EOF;
290  return count;
291 }
292 
294  AVFrame *in)
295 {
296  int ret;
297 
298  if ((ret = ff_framesync_process_frame(fs, 1)) < 0)
299  return ret;
300  if ((ret = ff_framesync_add_frame(fs, FF_INLINK_IDX(inlink), in)) < 0)
301  return ret;
302  if ((ret = ff_framesync_process_frame(fs, 0)) < 0)
303  return ret;
304  return 0;
305 }
306 
308 {
309  AVFilterContext *ctx = outlink->src;
310  int input, ret;
311 
312  if ((ret = ff_framesync_process_frame(fs, 0)) < 0)
313  return ret;
314  if (ret > 0)
315  return 0;
316  if (fs->eof)
317  return AVERROR_EOF;
318  outlink->flags |= FF_LINK_FLAG_REQUEST_LOOP;
319  input = fs->in_request;
320  ret = ff_request_frame(ctx->inputs[input]);
321  if (ret == AVERROR_EOF) {
322  if ((ret = ff_framesync_add_frame(fs, input, NULL)) < 0)
323  return ret;
324  if ((ret = ff_framesync_process_frame(fs, 0)) < 0)
325  return ret;
326  ret = 0;
327  }
328  return ret;
329 }
static AVFrame * ff_bufqueue_get(struct FFBufQueue *queue)
Get the first buffer from the queue and remove it.
Definition: bufferqueue.h:98
#define NULL
Definition: coverity.c:32
This structure describes decoded (raw) audio or video data.
Definition: frame.h:171
static void framesync_sync_level_update(FFFrameSync *fs)
Definition: framesync.c:56
#define LIBAVUTIL_VERSION_INT
Definition: version.h:62
Main libavfilter public API header.
int(* on_event)(struct FFFrameSync *fs)
Callback called when a frame event is ready.
Definition: framesync.h:175
int num
numerator
Definition: rational.h:44
static void framesync_advance(FFFrameSync *fs)
Definition: framesync.c:113
int ff_framesync_configure(FFFrameSync *fs)
Configure a frame sync structure.
Definition: framesync.c:72
static const char * framesync_name(void *ptr)
Definition: framesync.c:29
int64_t pts
Timestamp of the current event.
Definition: framesync.h:170
enum FFFrameSyncExtMode before
Extrapolation mode for timestamps before the first frame.
Definition: framesync.h:93
AVFilterLink ** inputs
array of pointers to input links
Definition: avfilter.h:641
#define av_assert0(cond)
assert() equivalent, that is always enabled.
Definition: avassert.h:37
uint8_t have_next
Boolean flagging the next frame, for internal use.
Definition: framesync.h:128
if()
Definition: avfilter.c:975
void * parent
Definition: framesync.h:155
void ff_framesync_next(FFFrameSync *fs)
Prepare the next frame event.
Definition: framesync.c:207
int64_t pts
Presentation timestamp in time_base units (time when frame should be shown to user).
Definition: frame.h:257
unsigned sync_level
Synchronization level: only inputs with the same sync level are sync sources.
Definition: framesync.h:191
static AVFrame * frame
#define AVERROR_EOF
End of file.
Definition: error.h:55
#define AV_LOG_VERBOSE
Detailed information.
Definition: log.h:192
enum FFFrameSyncExtMode after
Extrapolation mode for timestamps after the last frame.
Definition: framesync.h:98
int ff_framesync_process_frame(FFFrameSync *fs, unsigned all)
Process one or several frame using the on_event callback.
Definition: framesync.c:272
#define av_log(a,...)
int64_t av_rescale_q(int64_t a, AVRational bq, AVRational cq)
Rescale a 64-bit integer by 2 rational numbers.
Definition: mathematics.c:140
int ff_framesync_filter_frame(FFFrameSync *fs, AVFilterLink *inlink, AVFrame *in)
Accept a frame on a filter input.
Definition: framesync.c:293
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:176
void ff_framesync_uninit(FFFrameSync *fs)
Free all memory currently allocated.
Definition: framesync.c:261
AVFrame * frame_next
Next frame, for internal use.
Definition: framesync.h:113
Frame sync structure.
Definition: framesync.h:153
#define AVERROR(e)
Definition: error.h:43
void av_frame_free(AVFrame **frame)
Free the frame and any dynamically allocated objects in it, e.g.
Definition: frame.c:148
#define OFFSET(member)
Definition: framesync.c:27
simple assert() macros that are a bit more flexible than ISO C assert().
int64_t av_gcd(int64_t a, int64_t b)
Return the greatest common divisor of a and b.
Definition: mathematics.c:55
AVRational time_base
Time base for the incoming frames.
Definition: framesync.h:103
GLsizei count
Definition: opengl_enc.c:109
#define FFMAX(a, b)
Definition: common.h:64
uint8_t eof
Flag indicating that output has reached EOF.
Definition: framesync.h:201
#define av_assert1(cond)
assert() equivalent, that does not lie in speed critical code.
Definition: avassert.h:53
#define AV_TIME_BASE
Internal time base represented as integer.
Definition: avutil.h:247
unsigned in_request
Index of the input that requires a request.
Definition: framesync.h:185
int ff_framesync_request_frame(FFFrameSync *fs, AVFilterLink *outlink)
Request a frame on the filter output.
Definition: framesync.c:307
ret
Definition: avfilter.c:974
int ff_framesync_add_frame(FFFrameSync *fs, unsigned in, AVFrame *frame)
Add a frame to an input.
Definition: framesync.c:197
AVRational time_base
Time base for the output events.
Definition: framesync.h:165
struct FFBufQueue queue
Queue of incoming AVFrame, and NULL to mark EOF.
Definition: framesync.h:88
static void ff_bufqueue_discard_all(struct FFBufQueue *queue)
Unref and remove all buffers from the queue.
Definition: bufferqueue.h:111
static int64_t framesync_pts_extrapolate(FFFrameSync *fs, unsigned in, int64_t pts)
Definition: framesync.c:171
AVFrame * av_frame_clone(const AVFrame *src)
Create a new frame that references the same data as src.
Definition: frame.c:449
static const AVClass framesync_class
Definition: framesync.c:34
Extend the frame to infinity.
Definition: framesync.h:77
unsigned short available
number of available buffers
Definition: bufferqueue.h:52
void ff_framesync_init(FFFrameSync *fs, void *parent, unsigned nb_in)
Initialize a frame sync structure.
Definition: framesync.c:49
uint8_t pi<< 24) CONV_FUNC_GROUP(AV_SAMPLE_FMT_FLT, float, AV_SAMPLE_FMT_U8, uint8_t,(*(constuint8_t *) pi-0x80)*(1.0f/(1<< 7))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_DBL, double, AV_SAMPLE_FMT_U8, uint8_t,(*(constuint8_t *) pi-0x80)*(1.0/(1<< 7))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_U8, uint8_t, AV_SAMPLE_FMT_S16, int16_t,(*(constint16_t *) pi >>8)+0x80) CONV_FUNC_GROUP(AV_SAMPLE_FMT_FLT, float, AV_SAMPLE_FMT_S16, int16_t,*(constint16_t *) pi *(1.0f/(1<< 15))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_DBL, double, AV_SAMPLE_FMT_S16, int16_t,*(constint16_t *) pi *(1.0/(1<< 15))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_U8, uint8_t, AV_SAMPLE_FMT_S32, int32_t,(*(constint32_t *) pi >>24)+0x80) CONV_FUNC_GROUP(AV_SAMPLE_FMT_FLT, float, AV_SAMPLE_FMT_S32, int32_t,*(constint32_t *) pi *(1.0f/(1U<< 31))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_DBL, double, AV_SAMPLE_FMT_S32, int32_t,*(constint32_t *) pi *(1.0/(1U<< 31))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_U8, uint8_t, AV_SAMPLE_FMT_FLT, float, av_clip_uint8(lrintf(*(constfloat *) pi *(1<< 7))+0x80)) CONV_FUNC_GROUP(AV_SAMPLE_FMT_S16, int16_t, AV_SAMPLE_FMT_FLT, float, av_clip_int16(lrintf(*(constfloat *) pi *(1<< 15)))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_S32, int32_t, AV_SAMPLE_FMT_FLT, float, av_clipl_int32(llrintf(*(constfloat *) pi *(1U<< 31)))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_U8, uint8_t, AV_SAMPLE_FMT_DBL, double, av_clip_uint8(lrint(*(constdouble *) pi *(1<< 7))+0x80)) CONV_FUNC_GROUP(AV_SAMPLE_FMT_S16, int16_t, AV_SAMPLE_FMT_DBL, double, av_clip_int16(lrint(*(constdouble *) pi *(1<< 15)))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_S32, int32_t, AV_SAMPLE_FMT_DBL, double, av_clipl_int32(llrint(*(constdouble *) pi *(1U<< 31))))#defineSET_CONV_FUNC_GROUP(ofmt, ifmt) staticvoidset_generic_function(AudioConvert *ac){}voidff_audio_convert_free(AudioConvert **ac){if(!*ac) return;ff_dither_free(&(*ac) ->dc);av_freep(ac);}AudioConvert *ff_audio_convert_alloc(AVAudioResampleContext *avr, enumAVSampleFormatout_fmt, enumAVSampleFormatin_fmt, intchannels, intsample_rate, intapply_map){AudioConvert *ac;intin_planar, out_planar;ac=av_mallocz(sizeof(*ac));if(!ac) returnNULL;ac->avr=avr;ac->out_fmt=out_fmt;ac->in_fmt=in_fmt;ac->channels=channels;ac->apply_map=apply_map;if(avr->dither_method!=AV_RESAMPLE_DITHER_NONE &&av_get_packed_sample_fmt(out_fmt)==AV_SAMPLE_FMT_S16 &&av_get_bytes_per_sample(in_fmt)>2){ac->dc=ff_dither_alloc(avr, out_fmt, in_fmt, channels, sample_rate, apply_map);if(!ac->dc){av_free(ac);returnNULL;}returnac;}in_planar=ff_sample_fmt_is_planar(in_fmt, channels);out_planar=ff_sample_fmt_is_planar(out_fmt, channels);if(in_planar==out_planar){ac->func_type=CONV_FUNC_TYPE_FLAT;ac->planes=in_planar?ac->channels:1;}elseif(in_planar) ac->func_type=CONV_FUNC_TYPE_INTERLEAVE;elseac->func_type=CONV_FUNC_TYPE_DEINTERLEAVE;set_generic_function(ac);if(ARCH_AARCH64) ff_audio_convert_init_aarch64(ac);if(ARCH_ARM) ff_audio_convert_init_arm(ac);if(ARCH_X86) ff_audio_convert_init_x86(ac);returnac;}intff_audio_convert(AudioConvert *ac, AudioData *out, AudioData *in){intuse_generic=1;intlen=in->nb_samples;intp;if(ac->dc){av_log(ac->avr, AV_LOG_TRACE,"%dsamples-audio_convert:%sto%s(dithered)\n", len, av_get_sample_fmt_name(ac->in_fmt), av_get_sample_fmt_name(ac->out_fmt));returnff_convert_dither(ac-> in
uint8_t state
State: before first, in stream or after EOF, for internal use.
Definition: framesync.h:133
unsigned sync
Synchronization level: frames on input at the highest sync level will generate output frame events...
Definition: framesync.h:146
Describe the class of an AVClass context structure.
Definition: log.h:67
unsigned nb_in
Number of input streams.
Definition: framesync.h:160
AVFrame * frame
Current frame, may be NULL before the first one or after EOF.
Definition: framesync.h:108
static int64_t pts
Global timestamp for the audio frames.
int av_frame_make_writable(AVFrame *frame)
Ensure that the frame data is writable, avoiding data copy if possible.
Definition: frame.c:505
Frame requests may need to loop in order to be fulfilled.
Definition: internal.h:359
uint8_t frame_ready
Flag indicating that a frame event is ready.
Definition: framesync.h:196
uint8_t level
Definition: svq3.c:150
int version
LIBAVUTIL_VERSION with which this structure was created.
Definition: log.h:93
#define FF_INLINK_IDX(link)
Find the index of a link.
Definition: internal.h:330
int64_t pts
PTS of the current frame.
Definition: framesync.h:118
int den
denominator
Definition: rational.h:45
Completely stop all streams with this one.
Definition: framesync.h:67
void ff_framesync_drop(FFFrameSync *fs)
Drop the current frame event.
Definition: framesync.c:219
An instance of a filter.
Definition: avfilter.h:633
static void ff_bufqueue_add(void *log, struct FFBufQueue *queue, AVFrame *buf)
Add a buffer to the queue.
Definition: bufferqueue.h:71
static void framesync_inject_frame(FFFrameSync *fs, unsigned in, AVFrame *frame)
Definition: framesync.c:178
int ff_request_frame(AVFilterLink *link)
Request an input frame from the filter at the other end of the link.
Definition: avfilter.c:343
internal API functions
int ff_framesync_get_frame(FFFrameSync *fs, unsigned in, AVFrame **rframe, unsigned get)
Get the current frame in an input.
Definition: framesync.c:224
FFFrameSyncIn in[1]
Array of inputs; all inputs must be in consecutive memory.
Definition: framesync.h:206
#define AV_NOPTS_VALUE
Undefined timestamp value.
Definition: avutil.h:241
const AVClass * class
Definition: framesync.h:154
int64_t pts_next
PTS of the next frame, for internal use.
Definition: framesync.h:123