1 /*
2 * Copyright (C) 2010 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 * http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17 //#define LOG_NDEBUG 0
18 #define LOG_TAG "MPEG2TSExtractor"
19
20 #include <inttypes.h>
21 #include <utils/Log.h>
22
23 #include "MPEG2TSExtractor.h"
24
25 #include <media/DataSourceBase.h>
26 #include <media/IStreamSource.h>
27 #include <media/MediaTrack.h>
28 #include <media/stagefright/foundation/ABuffer.h>
29 #include <media/stagefright/foundation/ADebug.h>
30 #include <media/stagefright/foundation/ALooper.h>
31 #include <media/stagefright/foundation/AUtils.h>
32 #include <media/stagefright/foundation/MediaKeys.h>
33 #include <media/stagefright/MediaDefs.h>
34 #include <media/stagefright/MediaErrors.h>
35 #include <media/stagefright/MetaData.h>
36 #include <utils/String8.h>
37
38 #include "mpeg2ts/AnotherPacketSource.h"
39 #include "mpeg2ts/ATSParser.h"
40
41 #include <hidl/HybridInterface.h>
42 #include <android/hardware/cas/1.0/ICas.h>
43
44 namespace android {
45
46 using hardware::cas::V1_0::ICas;
47
48 static const size_t kTSPacketSize = 188;
49 static const int kMaxDurationReadSize = 250000LL;
50 static const int kMaxDurationRetry = 6;
51
52 struct MPEG2TSSource : public MediaTrack {
53 MPEG2TSSource(
54 MPEG2TSExtractor *extractor,
55 const sp<AnotherPacketSource> &impl,
56 bool doesSeek);
57 virtual ~MPEG2TSSource();
58
59 virtual status_t start(MetaDataBase *params = NULL);
60 virtual status_t stop();
61 virtual status_t getFormat(MetaDataBase &);
62
63 virtual status_t read(
64 MediaBufferBase **buffer, const ReadOptions *options = NULL);
65
66 private:
67 MPEG2TSExtractor *mExtractor;
68 sp<AnotherPacketSource> mImpl;
69
70 // If there are both audio and video streams, only the video stream
71 // will signal seek on the extractor; otherwise the single stream will seek.
72 bool mDoesSeek;
73
74 DISALLOW_EVIL_CONSTRUCTORS(MPEG2TSSource);
75 };
76
MPEG2TSSource(MPEG2TSExtractor * extractor,const sp<AnotherPacketSource> & impl,bool doesSeek)77 MPEG2TSSource::MPEG2TSSource(
78 MPEG2TSExtractor *extractor,
79 const sp<AnotherPacketSource> &impl,
80 bool doesSeek)
81 : mExtractor(extractor),
82 mImpl(impl),
83 mDoesSeek(doesSeek) {
84 }
85
~MPEG2TSSource()86 MPEG2TSSource::~MPEG2TSSource() {
87 }
88
start(MetaDataBase *)89 status_t MPEG2TSSource::start(MetaDataBase *) {
90 return mImpl->start(NULL); // AnotherPacketSource::start() doesn't use its argument
91 }
92
stop()93 status_t MPEG2TSSource::stop() {
94 return mImpl->stop();
95 }
96
getFormat(MetaDataBase & meta)97 status_t MPEG2TSSource::getFormat(MetaDataBase &meta) {
98 sp<MetaData> implMeta = mImpl->getFormat();
99 meta = *implMeta;
100 return OK;
101 }
102
read(MediaBufferBase ** out,const ReadOptions * options)103 status_t MPEG2TSSource::read(
104 MediaBufferBase **out, const ReadOptions *options) {
105 *out = NULL;
106
107 int64_t seekTimeUs;
108 ReadOptions::SeekMode seekMode;
109 if (mDoesSeek && options && options->getSeekTo(&seekTimeUs, &seekMode)) {
110 // seek is needed
111 status_t err = mExtractor->seek(seekTimeUs, seekMode);
112 if (err != OK) {
113 return err;
114 }
115 }
116
117 if (mExtractor->feedUntilBufferAvailable(mImpl) != OK) {
118 return ERROR_END_OF_STREAM;
119 }
120
121 return mImpl->read(out, options);
122 }
123
124 ////////////////////////////////////////////////////////////////////////////////
125
MPEG2TSExtractor(DataSourceBase * source)126 MPEG2TSExtractor::MPEG2TSExtractor(DataSourceBase *source)
127 : mDataSource(source),
128 mParser(new ATSParser),
129 mLastSyncEvent(0),
130 mOffset(0) {
131 init();
132 }
133
countTracks()134 size_t MPEG2TSExtractor::countTracks() {
135 return mSourceImpls.size();
136 }
137
getTrack(size_t index)138 MediaTrack *MPEG2TSExtractor::getTrack(size_t index) {
139 if (index >= mSourceImpls.size()) {
140 return NULL;
141 }
142
143 // The seek reference track (video if present; audio otherwise) performs
144 // seek requests, while other tracks ignore requests.
145 return new MPEG2TSSource(this, mSourceImpls.editItemAt(index),
146 (mSeekSyncPoints == &mSyncPoints.editItemAt(index)));
147 }
148
getTrackMetaData(MetaDataBase & meta,size_t index,uint32_t)149 status_t MPEG2TSExtractor::getTrackMetaData(
150 MetaDataBase &meta,
151 size_t index, uint32_t /* flags */) {
152 sp<MetaData> implMeta = index < mSourceImpls.size()
153 ? mSourceImpls.editItemAt(index)->getFormat() : NULL;
154 if (implMeta == NULL) {
155 return UNKNOWN_ERROR;
156 }
157 meta = *implMeta;
158 return OK;
159 }
160
getMetaData(MetaDataBase & meta)161 status_t MPEG2TSExtractor::getMetaData(MetaDataBase &meta) {
162 meta.setCString(kKeyMIMEType, MEDIA_MIMETYPE_CONTAINER_MPEG2TS);
163
164 return OK;
165 }
166
167 //static
isScrambledFormat(MetaDataBase & format)168 bool MPEG2TSExtractor::isScrambledFormat(MetaDataBase &format) {
169 const char *mime;
170 return format.findCString(kKeyMIMEType, &mime)
171 && (!strcasecmp(MEDIA_MIMETYPE_VIDEO_SCRAMBLED, mime)
172 || !strcasecmp(MEDIA_MIMETYPE_AUDIO_SCRAMBLED, mime));
173 }
174
setMediaCas(const uint8_t * casToken,size_t size)175 status_t MPEG2TSExtractor::setMediaCas(const uint8_t* casToken, size_t size) {
176 HalToken halToken;
177 halToken.setToExternal((uint8_t*)casToken, size);
178 sp<ICas> cas = ICas::castFrom(retrieveHalInterface(halToken));
179 ALOGD("setMediaCas: %p", cas.get());
180
181 status_t err = mParser->setMediaCas(cas);
182 if (err == OK) {
183 ALOGI("All tracks now have descramblers");
184 init();
185 }
186 return err;
187 }
188
addSource(const sp<AnotherPacketSource> & impl)189 void MPEG2TSExtractor::addSource(const sp<AnotherPacketSource> &impl) {
190 bool found = false;
191 for (size_t i = 0; i < mSourceImpls.size(); i++) {
192 if (mSourceImpls[i] == impl) {
193 found = true;
194 break;
195 }
196 }
197 if (!found) {
198 mSourceImpls.push(impl);
199 }
200 }
201
init()202 void MPEG2TSExtractor::init() {
203 bool haveAudio = false;
204 bool haveVideo = false;
205 int64_t startTime = ALooper::GetNowUs();
206
207 status_t err;
208 while ((err = feedMore(true /* isInit */)) == OK
209 || err == ERROR_DRM_DECRYPT_UNIT_NOT_INITIALIZED) {
210 if (haveAudio && haveVideo) {
211 addSyncPoint_l(mLastSyncEvent);
212 mLastSyncEvent.reset();
213 break;
214 }
215 if (!haveVideo) {
216 sp<AnotherPacketSource> impl = mParser->getSource(ATSParser::VIDEO);
217
218 if (impl != NULL) {
219 sp<MetaData> format = impl->getFormat();
220 if (format != NULL) {
221 haveVideo = true;
222 addSource(impl);
223 if (!isScrambledFormat(*(format.get()))) {
224 mSyncPoints.push();
225 mSeekSyncPoints = &mSyncPoints.editTop();
226 }
227 }
228 }
229 }
230
231 if (!haveAudio) {
232 sp<AnotherPacketSource> impl = mParser->getSource(ATSParser::AUDIO);
233
234 if (impl != NULL) {
235 sp<MetaData> format = impl->getFormat();
236 if (format != NULL) {
237 haveAudio = true;
238 addSource(impl);
239 if (!isScrambledFormat(*(format.get()))) {
240 mSyncPoints.push();
241 if (!haveVideo) {
242 mSeekSyncPoints = &mSyncPoints.editTop();
243 }
244 }
245 }
246 }
247 }
248
249 addSyncPoint_l(mLastSyncEvent);
250 mLastSyncEvent.reset();
251
252 // ERROR_DRM_DECRYPT_UNIT_NOT_INITIALIZED is returned when the mpeg2ts
253 // is scrambled but we don't have a MediaCas object set. The extraction
254 // will only continue when setMediaCas() is called successfully.
255 if (err == ERROR_DRM_DECRYPT_UNIT_NOT_INITIALIZED) {
256 ALOGI("stopped parsing scrambled content, "
257 "haveAudio=%d, haveVideo=%d, elaspedTime=%" PRId64,
258 haveAudio, haveVideo, ALooper::GetNowUs() - startTime);
259 return;
260 }
261
262 // Wait only for 2 seconds to detect audio/video streams.
263 if (ALooper::GetNowUs() - startTime > 2000000ll) {
264 break;
265 }
266 }
267
268 off64_t size;
269 if (mDataSource->getSize(&size) == OK && (haveAudio || haveVideo)) {
270 sp<AnotherPacketSource> impl = haveVideo
271 ? mParser->getSource(ATSParser::VIDEO)
272 : mParser->getSource(ATSParser::AUDIO);
273 size_t prevSyncSize = 1;
274 int64_t durationUs = -1;
275 List<int64_t> durations;
276 // Estimate duration --- stabilize until you get <500ms deviation.
277 while (feedMore() == OK
278 && ALooper::GetNowUs() - startTime <= 2000000ll) {
279 if (mSeekSyncPoints->size() > prevSyncSize) {
280 prevSyncSize = mSeekSyncPoints->size();
281 int64_t diffUs = mSeekSyncPoints->keyAt(prevSyncSize - 1)
282 - mSeekSyncPoints->keyAt(0);
283 off64_t diffOffset = mSeekSyncPoints->valueAt(prevSyncSize - 1)
284 - mSeekSyncPoints->valueAt(0);
285 int64_t currentDurationUs = size * diffUs / diffOffset;
286 durations.push_back(currentDurationUs);
287 if (durations.size() > 5) {
288 durations.erase(durations.begin());
289 int64_t min = *durations.begin();
290 int64_t max = *durations.begin();
291 for (auto duration : durations) {
292 if (min > duration) {
293 min = duration;
294 }
295 if (max < duration) {
296 max = duration;
297 }
298 }
299 if (max - min < 500 * 1000) {
300 durationUs = currentDurationUs;
301 break;
302 }
303 }
304 }
305 }
306 status_t err;
307 int64_t bufferedDurationUs;
308 bufferedDurationUs = impl->getBufferedDurationUs(&err);
309 if (err == ERROR_END_OF_STREAM) {
310 durationUs = bufferedDurationUs;
311 }
312 if (durationUs > 0) {
313 const sp<MetaData> meta = impl->getFormat();
314 meta->setInt64(kKeyDuration, durationUs);
315 impl->setFormat(meta);
316 } else {
317 estimateDurationsFromTimesUsAtEnd();
318 }
319 }
320
321 ALOGI("haveAudio=%d, haveVideo=%d, elaspedTime=%" PRId64,
322 haveAudio, haveVideo, ALooper::GetNowUs() - startTime);
323 }
324
feedMore(bool isInit)325 status_t MPEG2TSExtractor::feedMore(bool isInit) {
326 Mutex::Autolock autoLock(mLock);
327
328 uint8_t packet[kTSPacketSize];
329 ssize_t n = mDataSource->readAt(mOffset, packet, kTSPacketSize);
330
331 if (n < (ssize_t)kTSPacketSize) {
332 if (n >= 0) {
333 mParser->signalEOS(ERROR_END_OF_STREAM);
334 }
335 return (n < 0) ? (status_t)n : ERROR_END_OF_STREAM;
336 }
337
338 ATSParser::SyncEvent event(mOffset);
339 mOffset += n;
340 status_t err = mParser->feedTSPacket(packet, kTSPacketSize, &event);
341 if (event.hasReturnedData()) {
342 if (isInit) {
343 mLastSyncEvent = event;
344 } else {
345 addSyncPoint_l(event);
346 }
347 }
348 return err;
349 }
350
addSyncPoint_l(const ATSParser::SyncEvent & event)351 void MPEG2TSExtractor::addSyncPoint_l(const ATSParser::SyncEvent &event) {
352 if (!event.hasReturnedData()) {
353 return;
354 }
355
356 for (size_t i = 0; i < mSourceImpls.size(); ++i) {
357 if (mSourceImpls[i].get() == event.getMediaSource().get()) {
358 KeyedVector<int64_t, off64_t> *syncPoints = &mSyncPoints.editItemAt(i);
359 syncPoints->add(event.getTimeUs(), event.getOffset());
360 // We're keeping the size of the sync points at most 5mb per a track.
361 size_t size = syncPoints->size();
362 if (size >= 327680) {
363 int64_t firstTimeUs = syncPoints->keyAt(0);
364 int64_t lastTimeUs = syncPoints->keyAt(size - 1);
365 if (event.getTimeUs() - firstTimeUs > lastTimeUs - event.getTimeUs()) {
366 syncPoints->removeItemsAt(0, 4096);
367 } else {
368 syncPoints->removeItemsAt(size - 4096, 4096);
369 }
370 }
371 break;
372 }
373 }
374 }
375
estimateDurationsFromTimesUsAtEnd()376 status_t MPEG2TSExtractor::estimateDurationsFromTimesUsAtEnd() {
377 if (!(mDataSource->flags() & DataSourceBase::kIsLocalFileSource)) {
378 return ERROR_UNSUPPORTED;
379 }
380
381 off64_t size = 0;
382 status_t err = mDataSource->getSize(&size);
383 if (err != OK) {
384 return err;
385 }
386
387 uint8_t packet[kTSPacketSize];
388 const off64_t zero = 0;
389 off64_t offset = max(zero, size - kMaxDurationReadSize);
390 if (mDataSource->readAt(offset, &packet, 0) < 0) {
391 return ERROR_IO;
392 }
393
394 int retry = 0;
395 bool allDurationsFound = false;
396 int64_t timeAnchorUs = mParser->getFirstPTSTimeUs();
397 do {
398 int bytesRead = 0;
399 sp<ATSParser> parser = new ATSParser(ATSParser::TS_TIMESTAMPS_ARE_ABSOLUTE);
400 ATSParser::SyncEvent ev(0);
401 offset = max(zero, size - (kMaxDurationReadSize << retry));
402 offset = (offset / kTSPacketSize) * kTSPacketSize;
403 for (;;) {
404 if (bytesRead >= kMaxDurationReadSize << max(0, retry - 1)) {
405 break;
406 }
407
408 ssize_t n = mDataSource->readAt(offset, packet, kTSPacketSize);
409 if (n < 0) {
410 return n;
411 } else if (n < (ssize_t)kTSPacketSize) {
412 break;
413 }
414
415 offset += kTSPacketSize;
416 bytesRead += kTSPacketSize;
417 err = parser->feedTSPacket(packet, kTSPacketSize, &ev);
418 if (err != OK) {
419 return err;
420 }
421
422 if (ev.hasReturnedData()) {
423 int64_t durationUs = ev.getTimeUs();
424 ATSParser::SourceType type = ev.getType();
425 ev.reset();
426
427 int64_t firstTimeUs;
428 sp<AnotherPacketSource> src = mParser->getSource(type);
429 if (src == NULL || src->nextBufferTime(&firstTimeUs) != OK) {
430 continue;
431 }
432 durationUs += src->getEstimatedBufferDurationUs();
433 durationUs -= timeAnchorUs;
434 durationUs -= firstTimeUs;
435 if (durationUs > 0) {
436 int64_t origDurationUs, lastDurationUs;
437 const sp<MetaData> meta = src->getFormat();
438 const uint32_t kKeyLastDuration = 'ldur';
439 // Require two consecutive duration calculations to be within 1 sec before
440 // updating; use MetaData to store previous duration estimate in per-stream
441 // context.
442 if (!meta->findInt64(kKeyDuration, &origDurationUs)
443 || !meta->findInt64(kKeyLastDuration, &lastDurationUs)
444 || (origDurationUs < durationUs
445 && abs(durationUs - lastDurationUs) < 60000000)) {
446 meta->setInt64(kKeyDuration, durationUs);
447 }
448 meta->setInt64(kKeyLastDuration, durationUs);
449 }
450 }
451 }
452
453 if (!allDurationsFound) {
454 allDurationsFound = true;
455 for (auto t: {ATSParser::VIDEO, ATSParser::AUDIO}) {
456 sp<AnotherPacketSource> src = mParser->getSource(t);
457 if (src == NULL) {
458 continue;
459 }
460 int64_t durationUs;
461 const sp<MetaData> meta = src->getFormat();
462 if (!meta->findInt64(kKeyDuration, &durationUs)) {
463 allDurationsFound = false;
464 break;
465 }
466 }
467 }
468
469 ++retry;
470 } while(!allDurationsFound && offset > 0 && retry <= kMaxDurationRetry);
471
472 return allDurationsFound? OK : ERROR_UNSUPPORTED;
473 }
474
flags() const475 uint32_t MPEG2TSExtractor::flags() const {
476 return CAN_PAUSE | CAN_SEEK_BACKWARD | CAN_SEEK_FORWARD;
477 }
478
seek(int64_t seekTimeUs,const MediaTrack::ReadOptions::SeekMode & seekMode)479 status_t MPEG2TSExtractor::seek(int64_t seekTimeUs,
480 const MediaTrack::ReadOptions::SeekMode &seekMode) {
481 if (mSeekSyncPoints == NULL || mSeekSyncPoints->isEmpty()) {
482 ALOGW("No sync point to seek to.");
483 // ... and therefore we have nothing useful to do here.
484 return OK;
485 }
486
487 // Determine whether we're seeking beyond the known area.
488 bool shouldSeekBeyond =
489 (seekTimeUs > mSeekSyncPoints->keyAt(mSeekSyncPoints->size() - 1));
490
491 // Determine the sync point to seek.
492 size_t index = 0;
493 for (; index < mSeekSyncPoints->size(); ++index) {
494 int64_t timeUs = mSeekSyncPoints->keyAt(index);
495 if (timeUs > seekTimeUs) {
496 break;
497 }
498 }
499
500 switch (seekMode) {
501 case MediaTrack::ReadOptions::SEEK_NEXT_SYNC:
502 if (index == mSeekSyncPoints->size()) {
503 ALOGW("Next sync not found; starting from the latest sync.");
504 --index;
505 }
506 break;
507 case MediaTrack::ReadOptions::SEEK_CLOSEST_SYNC:
508 case MediaTrack::ReadOptions::SEEK_CLOSEST:
509 ALOGW("seekMode not supported: %d; falling back to PREVIOUS_SYNC",
510 seekMode);
511 // fall-through
512 case MediaTrack::ReadOptions::SEEK_PREVIOUS_SYNC:
513 if (index == 0) {
514 ALOGW("Previous sync not found; starting from the earliest "
515 "sync.");
516 } else {
517 --index;
518 }
519 break;
520 default:
521 return ERROR_UNSUPPORTED;
522 }
523 if (!shouldSeekBeyond || mOffset <= mSeekSyncPoints->valueAt(index)) {
524 int64_t actualSeekTimeUs = mSeekSyncPoints->keyAt(index);
525 mOffset = mSeekSyncPoints->valueAt(index);
526 status_t err = queueDiscontinuityForSeek(actualSeekTimeUs);
527 if (err != OK) {
528 return err;
529 }
530 }
531
532 if (shouldSeekBeyond) {
533 status_t err = seekBeyond(seekTimeUs);
534 if (err != OK) {
535 return err;
536 }
537 }
538
539 // Fast-forward to sync frame.
540 for (size_t i = 0; i < mSourceImpls.size(); ++i) {
541 const sp<AnotherPacketSource> &impl = mSourceImpls[i];
542 status_t err;
543 feedUntilBufferAvailable(impl);
544 while (impl->hasBufferAvailable(&err)) {
545 sp<AMessage> meta = impl->getMetaAfterLastDequeued(0);
546 sp<ABuffer> buffer;
547 if (meta == NULL) {
548 return UNKNOWN_ERROR;
549 }
550 int32_t sync;
551 if (meta->findInt32("isSync", &sync) && sync) {
552 break;
553 }
554 err = impl->dequeueAccessUnit(&buffer);
555 if (err != OK) {
556 return err;
557 }
558 feedUntilBufferAvailable(impl);
559 }
560 }
561
562 return OK;
563 }
564
queueDiscontinuityForSeek(int64_t actualSeekTimeUs)565 status_t MPEG2TSExtractor::queueDiscontinuityForSeek(int64_t actualSeekTimeUs) {
566 // Signal discontinuity
567 sp<AMessage> extra(new AMessage);
568 extra->setInt64(kATSParserKeyMediaTimeUs, actualSeekTimeUs);
569 mParser->signalDiscontinuity(ATSParser::DISCONTINUITY_TIME, extra);
570
571 // After discontinuity, impl should only have discontinuities
572 // with the last being what we queued. Dequeue them all here.
573 for (size_t i = 0; i < mSourceImpls.size(); ++i) {
574 const sp<AnotherPacketSource> &impl = mSourceImpls.itemAt(i);
575 sp<ABuffer> buffer;
576 status_t err;
577 while (impl->hasBufferAvailable(&err)) {
578 if (err != OK) {
579 return err;
580 }
581 err = impl->dequeueAccessUnit(&buffer);
582 // If the source contains anything but discontinuity, that's
583 // a programming mistake.
584 CHECK(err == INFO_DISCONTINUITY);
585 }
586 }
587
588 // Feed until we have a buffer for each source.
589 for (size_t i = 0; i < mSourceImpls.size(); ++i) {
590 const sp<AnotherPacketSource> &impl = mSourceImpls.itemAt(i);
591 sp<ABuffer> buffer;
592 status_t err = feedUntilBufferAvailable(impl);
593 if (err != OK) {
594 return err;
595 }
596 }
597
598 return OK;
599 }
600
seekBeyond(int64_t seekTimeUs)601 status_t MPEG2TSExtractor::seekBeyond(int64_t seekTimeUs) {
602 // If we're seeking beyond where we know --- read until we reach there.
603 size_t syncPointsSize = mSeekSyncPoints->size();
604
605 while (seekTimeUs > mSeekSyncPoints->keyAt(
606 mSeekSyncPoints->size() - 1)) {
607 status_t err;
608 if (syncPointsSize < mSeekSyncPoints->size()) {
609 syncPointsSize = mSeekSyncPoints->size();
610 int64_t syncTimeUs = mSeekSyncPoints->keyAt(syncPointsSize - 1);
611 // Dequeue buffers before sync point in order to avoid too much
612 // cache building up.
613 sp<ABuffer> buffer;
614 for (size_t i = 0; i < mSourceImpls.size(); ++i) {
615 const sp<AnotherPacketSource> &impl = mSourceImpls[i];
616 int64_t timeUs;
617 while ((err = impl->nextBufferTime(&timeUs)) == OK) {
618 if (timeUs < syncTimeUs) {
619 impl->dequeueAccessUnit(&buffer);
620 } else {
621 break;
622 }
623 }
624 if (err != OK && err != -EWOULDBLOCK) {
625 return err;
626 }
627 }
628 }
629 if (feedMore() != OK) {
630 return ERROR_END_OF_STREAM;
631 }
632 }
633
634 return OK;
635 }
636
feedUntilBufferAvailable(const sp<AnotherPacketSource> & impl)637 status_t MPEG2TSExtractor::feedUntilBufferAvailable(
638 const sp<AnotherPacketSource> &impl) {
639 status_t finalResult;
640 while (!impl->hasBufferAvailable(&finalResult)) {
641 if (finalResult != OK) {
642 return finalResult;
643 }
644
645 status_t err = feedMore();
646 if (err != OK) {
647 impl->signalEOS(err);
648 }
649 }
650 return OK;
651 }
652
653 ////////////////////////////////////////////////////////////////////////////////
654
SniffMPEG2TS(DataSourceBase * source,float * confidence)655 bool SniffMPEG2TS(DataSourceBase *source, float *confidence) {
656 for (int i = 0; i < 5; ++i) {
657 char header;
658 if (source->readAt(kTSPacketSize * i, &header, 1) != 1
659 || header != 0x47) {
660 return false;
661 }
662 }
663
664 *confidence = 0.1f;
665
666 return true;
667 }
668
669 } // namespace android
670