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- Committer: Bazaar Package Importer
- Author(s): Reinhard Tartler
- Date: 2010-06-16 12:53:24 UTC
- mfrom: (1.1.13 upstream)
- Revision ID: james.westby@ubuntu.com-20100616125324-kbhhjn7012ufc79t
Tags: 4:0.6-1ubuntu1
* merge from debian/experimental. remaining changes:
- don't disable encoders
- don't build against libfaad, libdirac and libopenjpeg (all in universe)
* new upstream release
- internal vorbis encoder is disabled. LP: #585330
- includes native AMR-NB decoder, LP: #93849
- api-example is fixed: LP: #557319
- don't disable encoders
- don't build against libfaad, libdirac and libopenjpeg (all in universe)
* new upstream release
- internal vorbis encoder is disabled. LP: #585330
- includes native AMR-NB decoder, LP: #93849
- api-example is fixed: LP: #557319
- files added:
- RELEASE
- files removed:
- .svnrevision
- files modified:
- Changelog
added
removed
libavformat/movenchint.c
1
/*
2
* MOV, 3GP, MP4 muxer RTP hinting
3
* Copyright (c) 2010 Martin Storsjo
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
#include "movenc.h"
23
#include "libavutil/intreadwrite.h"
24
25
int ff_mov_init_hinting(AVFormatContext *s, int index, int src_index)
26
{
27
MOVMuxContext *mov = s->priv_data;
28
MOVTrack *track = &mov->tracks[index];
29
MOVTrack *src_track = &mov->tracks[src_index];
30
AVStream *src_st = s->streams[src_index];
31
int ret = AVERROR(ENOMEM);
32
AVOutputFormat *rtp_format = av_guess_format("rtp", NULL, NULL);
33
34
track->tag = MKTAG('r','t','p',' ');
35
track->src_track = src_index;
36
37
if (!rtp_format) {
38
ret = AVERROR(ENOENT);
39
goto fail;
40
}
41
42
track->enc = avcodec_alloc_context();
43
if (!track->enc)
44
goto fail;
45
track->enc->codec_type = AVMEDIA_TYPE_DATA;
46
track->enc->codec_tag = track->tag;
47
48
track->rtp_ctx = avformat_alloc_context();
49
if (!track->rtp_ctx)
50
goto fail;
51
track->rtp_ctx->oformat = rtp_format;
52
if (!av_new_stream(track->rtp_ctx, 0))
53
goto fail;
54
55
/* Copy stream parameters */
56
track->rtp_ctx->streams[0]->sample_aspect_ratio =
57
src_st->sample_aspect_ratio;
58
59
/* Remove the allocated codec context, link to the original one
60
* instead, to give the rtp muxer access to codec parameters. */
61
av_free(track->rtp_ctx->streams[0]->codec);
62
track->rtp_ctx->streams[0]->codec = src_st->codec;
63
64
if ((ret = url_open_dyn_packet_buf(&track->rtp_ctx->pb,
65
RTP_MAX_PACKET_SIZE)) < 0)
66
goto fail;
67
ret = av_write_header(track->rtp_ctx);
68
if (ret)
69
goto fail;
70
71
/* Copy the RTP AVStream timebase back to the hint AVStream */
72
track->timescale = track->rtp_ctx->streams[0]->time_base.den;
73
74
/* Mark the hinted track that packets written to it should be
75
* sent to this track for hinting. */
76
src_track->hint_track = index;
77
return 0;
78
fail:
79
av_log(s, AV_LOG_WARNING,
80
"Unable to initialize hinting of stream %d\n", src_index);
81
if (track->rtp_ctx && track->rtp_ctx->pb) {
82
uint8_t *buf;
83
url_close_dyn_buf(track->rtp_ctx->pb, &buf);
84
av_free(buf);
85
}
86
if (track->rtp_ctx && track->rtp_ctx->streams[0]) {
87
av_metadata_free(&track->rtp_ctx->streams[0]->metadata);
88
av_free(track->rtp_ctx->streams[0]);
89
}
90
if (track->rtp_ctx) {
91
av_metadata_free(&track->rtp_ctx->metadata);
92
av_free(track->rtp_ctx->priv_data);
93
av_freep(&track->rtp_ctx);
94
}
95
av_freep(&track->enc);
96
/* Set a default timescale, to avoid crashes in dump_format */
97
track->timescale = 90000;
98
return ret;
99
}
100
101
/**
102
* Remove the first sample from the sample queue.
103
*/
104
static void sample_queue_pop(HintSampleQueue *queue)
105
{
106
if (queue->len <= 0)
107
return;
108
if (queue->samples[0].own_data)
109
av_free(queue->samples[0].data);
110
queue->len--;
111
memmove(queue->samples, queue->samples + 1, sizeof(HintSample)*queue->len);
112
}
113
114
/**
115
* Empty the sample queue, releasing all memory.
116
*/
117
static void sample_queue_free(HintSampleQueue *queue)
118
{
119
int i;
120
for (i = 0; i < queue->len; i++)
121
if (queue->samples[i].own_data)
122
av_free(queue->samples[i].data);
123
av_freep(&queue->samples);
124
queue->len = 0;
125
queue->size = 0;
126
}
127
128
/**
129
* Add a reference to the sample data to the sample queue. The data is
130
* not copied. sample_queue_retain should be called before pkt->data
131
* is reused/freed.
132
*/
133
static void sample_queue_push(HintSampleQueue *queue, AVPacket *pkt, int sample)
134
{
135
/* No need to keep track of smaller samples, since describing them
136
* with immediates is more efficient. */
137
if (pkt->size <= 14)
138
return;
139
if (!queue->samples || queue->len >= queue->size) {
140
HintSample* samples;
141
queue->size += 10;
142
samples = av_realloc(queue->samples, sizeof(HintSample)*queue->size);
143
if (!samples)
144
return;
145
queue->samples = samples;
146
}
147
queue->samples[queue->len].data = pkt->data;
148
queue->samples[queue->len].size = pkt->size;
149
queue->samples[queue->len].sample_number = sample;
150
queue->samples[queue->len].offset = 0;
151
queue->samples[queue->len].own_data = 0;
152
queue->len++;
153
}
154
155
/**
156
* Make local copies of all referenced sample data in the queue.
157
*/
158
static void sample_queue_retain(HintSampleQueue *queue)
159
{
160
int i;
161
for (i = 0; i < queue->len; ) {
162
HintSample *sample = &queue->samples[i];
163
if (!sample->own_data) {
164
uint8_t* ptr = av_malloc(sample->size);
165
if (!ptr) {
166
/* Unable to allocate memory for this one, remove it */
167
memmove(queue->samples + i, queue->samples + i + 1,
168
sizeof(HintSample)*(queue->len - i - 1));
169
queue->len--;
170
continue;
171
}
172
memcpy(ptr, sample->data, sample->size);
173
sample->data = ptr;
174
sample->own_data = 1;
175
}
176
i++;
177
}
178
}
179
180
/**
181
* Find matches of needle[n_pos ->] within haystack. If a sufficiently
182
* large match is found, matching bytes before n_pos are included
183
* in the match, too (within the limits of the arrays).
184
*
185
* @param haystack buffer that may contain parts of needle
186
* @param h_len length of the haystack buffer
187
* @param needle buffer containing source data that have been used to
188
* construct haystack
189
* @param n_pos start position in needle used for looking for matches
190
* @param n_len length of the needle buffer
191
* @param match_h_offset_ptr offset of the first matching byte within haystack
192
* @param match_n_offset_ptr offset of the first matching byte within needle
193
* @param match_len_ptr length of the matched segment
194
* @return 0 if a match was found, < 0 if no match was found
195
*/
196
static int match_segments(const uint8_t *haystack, int h_len,
197
const uint8_t *needle, int n_pos, int n_len,
198
int *match_h_offset_ptr, int *match_n_offset_ptr,
199
int *match_len_ptr)
200
{
201
int h_pos;
202
for (h_pos = 0; h_pos < h_len; h_pos++) {
203
int match_len = 0;
204
int match_h_pos, match_n_pos;
205
206
/* Check how many bytes match at needle[n_pos] and haystack[h_pos] */
207
while (h_pos + match_len < h_len && n_pos + match_len < n_len &&
208
needle[n_pos + match_len] == haystack[h_pos + match_len])
209
match_len++;
210
if (match_len <= 8)
211
continue;
212
213
/* If a sufficiently large match was found, try to expand
214
* the matched segment backwards. */
215
match_h_pos = h_pos;
216
match_n_pos = n_pos;
217
while (match_n_pos > 0 && match_h_pos > 0 &&
218
needle[match_n_pos - 1] == haystack[match_h_pos - 1]) {
219
match_n_pos--;
220
match_h_pos--;
221
match_len++;
222
}
223
if (match_len <= 14)
224
continue;
225
*match_h_offset_ptr = match_h_pos;
226
*match_n_offset_ptr = match_n_pos;
227
*match_len_ptr = match_len;
228
return 0;
229
}
230
return -1;
231
}
232
233
/**
234
* Look for segments in samples in the sample queue matching the data
235
* in ptr. Samples not matching are removed from the queue. If a match
236
* is found, the next time it will look for matches starting from the
237
* end of the previous matched segment.
238
*
239
* @param data data to find matches for in the sample queue
240
* @param len length of the data buffer
241
* @param queue samples used for looking for matching segments
242
* @param pos the offset in data of the matched segment
243
* @param match_sample the number of the sample that contained the match
244
* @param match_offset the offset of the matched segment within the sample
245
* @param match_len the length of the matched segment
246
* @return 0 if a match was found, < 0 if no match was found
247
*/
248
static int find_sample_match(const uint8_t *data, int len,
249
HintSampleQueue *queue, int *pos,
250
int *match_sample, int *match_offset,
251
int *match_len)
252
{
253
while (queue->len > 0) {
254
HintSample *sample = &queue->samples[0];
255
/* If looking for matches in a new sample, skip the first 5 bytes,
256
* since they often may be modified/removed in the output packet. */
257
if (sample->offset == 0 && sample->size > 5)
258
sample->offset = 5;
259
260
if (match_segments(data, len, sample->data, sample->offset,
261
sample->size, pos, match_offset, match_len) == 0) {
262
*match_sample = sample->sample_number;
263
/* Next time, look for matches at this offset, with a little
264
* margin to this match. */
265
sample->offset = *match_offset + *match_len + 5;
266
if (sample->offset + 10 >= sample->size)
267
sample_queue_pop(queue); /* Not enough useful data left */
268
return 0;
269
}
270
271
if (sample->offset < 10 && sample->size > 20) {
272
/* No match found from the start of the sample,
273
* try from the middle of the sample instead. */
274
sample->offset = sample->size/2;
275
} else {
276
/* No match for this sample, remove it */
277
sample_queue_pop(queue);
278
}
279
}
280
return -1;
281
}
282
283
static void output_immediate(const uint8_t *data, int size,
284
ByteIOContext *out, int *entries)
285
{
286
while (size > 0) {
287
int len = size;
288
if (len > 14)
289
len = 14;
290
put_byte(out, 1); /* immediate constructor */
291
put_byte(out, len); /* amount of valid data */
292
put_buffer(out, data, len);
293
data += len;
294
size -= len;
295
296
for (; len < 14; len++)
297
put_byte(out, 0);
298
299
(*entries)++;
300
}
301
}
302
303
static void output_match(ByteIOContext *out, int match_sample,
304
int match_offset, int match_len, int *entries)
305
{
306
put_byte(out, 2); /* sample constructor */
307
put_byte(out, 0); /* track reference */
308
put_be16(out, match_len);
309
put_be32(out, match_sample);
310
put_be32(out, match_offset);
311
put_be16(out, 1); /* bytes per block */
312
put_be16(out, 1); /* samples per block */
313
(*entries)++;
314
}
315
316
static void describe_payload(const uint8_t *data, int size,
317
ByteIOContext *out, int *entries,
318
HintSampleQueue *queue)
319
{
320
/* Describe the payload using different constructors */
321
while (size > 0) {
322
int match_sample, match_offset, match_len, pos;
323
if (find_sample_match(data, size, queue, &pos, &match_sample,
324
&match_offset, &match_len) < 0)
325
break;
326
output_immediate(data, pos, out, entries);
327
data += pos;
328
size -= pos;
329
output_match(out, match_sample, match_offset, match_len, entries);
330
data += match_len;
331
size -= match_len;
332
}
333
output_immediate(data, size, out, entries);
334
}
335
336
/**
337
* Write an RTP hint (that may contain one or more RTP packets)
338
* for the packets in data. data contains one or more packets with a
339
* BE32 size header.
340
*
341
* @param out buffer where the hints are written
342
* @param data buffer containing RTP packets
343
* @param size the size of the data buffer
344
* @param trk the MOVTrack for the hint track
345
* @param pts pointer where the timestamp for the written RTP hint is stored
346
* @return the number of RTP packets in the written hint
347
*/
348
static int write_hint_packets(ByteIOContext *out, const uint8_t *data,
349
int size, MOVTrack *trk, int64_t *pts)
350
{
351
int64_t curpos;
352
int64_t count_pos, entries_pos;
353
int count = 0, entries;
354
355
count_pos = url_ftell(out);
356
/* RTPsample header */
357
put_be16(out, 0); /* packet count */
358
put_be16(out, 0); /* reserved */
359
360
while (size > 4) {
361
uint32_t packet_len = AV_RB32(data);
362
uint16_t seq;
363
uint32_t ts;
364
365
data += 4;
366
size -= 4;
367
if (packet_len > size || packet_len <= 12)
368
break;
369
if (data[1] >= 200 && data[1] <= 204) {
370
/* RTCP packet, just skip */
371
data += packet_len;
372
size -= packet_len;
373
continue;
374
}
375
376
if (packet_len > trk->max_packet_size)
377
trk->max_packet_size = packet_len;
378
379
seq = AV_RB16(&data[2]);
380
ts = AV_RB32(&data[4]);
381
382
if (trk->prev_rtp_ts == 0)
383
trk->prev_rtp_ts = ts;
384
/* Unwrap the 32-bit RTP timestamp that wraps around often
385
* into a not (as often) wrapping 64-bit timestamp. */
386
trk->cur_rtp_ts_unwrapped += (int32_t) (ts - trk->prev_rtp_ts);
387
trk->prev_rtp_ts = ts;
388
if (*pts == AV_NOPTS_VALUE)
389
*pts = trk->cur_rtp_ts_unwrapped;
390
391
count++;
392
/* RTPpacket header */
393
put_be32(out, 0); /* relative_time */
394
put_buffer(out, data, 2); /* RTP header */
395
put_be16(out, seq); /* RTPsequenceseed */
396
put_be16(out, 0); /* reserved + flags */
397
entries_pos = url_ftell(out);
398
put_be16(out, 0); /* entry count */
399
400
data += 12;
401
size -= 12;
402
packet_len -= 12;
403
404
entries = 0;
405
/* Write one or more constructors describing the payload data */
406
describe_payload(data, packet_len, out, &entries, &trk->sample_queue);
407
data += packet_len;
408
size -= packet_len;
409
410
curpos = url_ftell(out);
411
url_fseek(out, entries_pos, SEEK_SET);
412
put_be16(out, entries);
413
url_fseek(out, curpos, SEEK_SET);
414
}
415
416
curpos = url_ftell(out);
417
url_fseek(out, count_pos, SEEK_SET);
418
put_be16(out, count);
419
url_fseek(out, curpos, SEEK_SET);
420
return count;
421
}
422
423
int ff_mov_add_hinted_packet(AVFormatContext *s, AVPacket *pkt,
424
int track_index, int sample)
425
{
426
MOVMuxContext *mov = s->priv_data;
427
MOVTrack *trk = &mov->tracks[track_index];
428
AVFormatContext *rtp_ctx = trk->rtp_ctx;
429
uint8_t *buf = NULL;
430
int size;
431
ByteIOContext *hintbuf = NULL;
432
AVPacket hint_pkt;
433
AVPacket local_pkt;
434
int ret = 0, count;
435
436
if (!rtp_ctx)
437
return AVERROR(ENOENT);
438
if (!rtp_ctx->pb)
439
return AVERROR(ENOMEM);
440
441
sample_queue_push(&trk->sample_queue, pkt, sample);
442
443
/* Feed the packet to the RTP muxer */
444
local_pkt = *pkt;
445
local_pkt.stream_index = 0;
446
local_pkt.pts = av_rescale_q(pkt->pts,
447
s->streams[pkt->stream_index]->time_base,
448
rtp_ctx->streams[0]->time_base);
449
local_pkt.dts = av_rescale_q(pkt->dts,
450
s->streams[pkt->stream_index]->time_base,
451
rtp_ctx->streams[0]->time_base);
452
av_write_frame(rtp_ctx, &local_pkt);
453
454
/* Fetch the output from the RTP muxer, open a new output buffer
455
* for next time. */
456
size = url_close_dyn_buf(rtp_ctx->pb, &buf);
457
if ((ret = url_open_dyn_packet_buf(&rtp_ctx->pb,
458
RTP_MAX_PACKET_SIZE)) < 0)
459
goto done;
460
461
if (size <= 0)
462
goto done;
463
464
/* Open a buffer for writing the hint */
465
if ((ret = url_open_dyn_buf(&hintbuf)) < 0)
466
goto done;
467
av_init_packet(&hint_pkt);
468
count = write_hint_packets(hintbuf, buf, size, trk, &hint_pkt.dts);
469
av_freep(&buf);
470
471
/* Write the hint data into the hint track */
472
hint_pkt.size = size = url_close_dyn_buf(hintbuf, &buf);
473
hint_pkt.data = buf;
474
hint_pkt.pts = hint_pkt.dts;
475
hint_pkt.stream_index = track_index;
476
if (pkt->flags & AV_PKT_FLAG_KEY)
477
hint_pkt.flags |= AV_PKT_FLAG_KEY;
478
if (count > 0)
479
ff_mov_write_packet(s, &hint_pkt);
480
done:
481
av_free(buf);
482
sample_queue_retain(&trk->sample_queue);
483
return ret;
484
}
485
486
void ff_mov_close_hinting(MOVTrack *track) {
487
AVFormatContext* rtp_ctx = track->rtp_ctx;
488
uint8_t *ptr;
489
490
av_freep(&track->enc);
491
sample_queue_free(&track->sample_queue);
492
if (!rtp_ctx)
493
return;
494
if (rtp_ctx->pb) {
495
av_write_trailer(rtp_ctx);
496
url_close_dyn_buf(rtp_ctx->pb, &ptr);
497
av_free(ptr);
498
}
499
av_metadata_free(&rtp_ctx->streams[0]->metadata);
500
av_metadata_free(&rtp_ctx->metadata);
501
av_free(rtp_ctx->streams[0]);
502
av_freep(&rtp_ctx);
503
}
504
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