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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 "include/MPEG2TSExtractor.h"
24 #include "include/NuCachedSource2.h"
25 
26 #include <media/stagefright/foundation/ABuffer.h>
27 #include <media/stagefright/foundation/ADebug.h>
28 #include <media/stagefright/foundation/ALooper.h>
29 #include <media/stagefright/foundation/AUtils.h>
30 #include <media/stagefright/DataSource.h>
31 #include <media/stagefright/MediaDefs.h>
32 #include <media/stagefright/MediaErrors.h>
33 #include <media/stagefright/MediaSource.h>
34 #include <media/stagefright/MetaData.h>
35 #include <media/IStreamSource.h>
36 #include <utils/String8.h>
37 
38 #include "AnotherPacketSource.h"
39 #include "ATSParser.h"
40 
41 namespace android {
42 
43 static const size_t kTSPacketSize = 188;
44 static const int kMaxDurationReadSize = 250000LL;
45 static const int kMaxDurationRetry = 6;
46 
47 struct MPEG2TSSource : public MediaSource {
48     MPEG2TSSource(
49             const sp<MPEG2TSExtractor> &extractor,
50             const sp<AnotherPacketSource> &impl,
51             bool doesSeek);
52 
53     virtual status_t start(MetaData *params = NULL);
54     virtual status_t stop();
55     virtual sp<MetaData> getFormat();
56 
57     virtual status_t read(
58             MediaBuffer **buffer, const ReadOptions *options = NULL);
59 
60 private:
61     sp<MPEG2TSExtractor> mExtractor;
62     sp<AnotherPacketSource> mImpl;
63 
64     // If there are both audio and video streams, only the video stream
65     // will signal seek on the extractor; otherwise the single stream will seek.
66     bool mDoesSeek;
67 
68     DISALLOW_EVIL_CONSTRUCTORS(MPEG2TSSource);
69 };
70 
MPEG2TSSource(const sp<MPEG2TSExtractor> & extractor,const sp<AnotherPacketSource> & impl,bool doesSeek)71 MPEG2TSSource::MPEG2TSSource(
72         const sp<MPEG2TSExtractor> &extractor,
73         const sp<AnotherPacketSource> &impl,
74         bool doesSeek)
75     : mExtractor(extractor),
76       mImpl(impl),
77       mDoesSeek(doesSeek) {
78 }
79 
start(MetaData * params)80 status_t MPEG2TSSource::start(MetaData *params) {
81     return mImpl->start(params);
82 }
83 
stop()84 status_t MPEG2TSSource::stop() {
85     return mImpl->stop();
86 }
87 
getFormat()88 sp<MetaData> MPEG2TSSource::getFormat() {
89     return mImpl->getFormat();
90 }
91 
read(MediaBuffer ** out,const ReadOptions * options)92 status_t MPEG2TSSource::read(
93         MediaBuffer **out, const ReadOptions *options) {
94     *out = NULL;
95 
96     int64_t seekTimeUs;
97     ReadOptions::SeekMode seekMode;
98     if (mDoesSeek && options && options->getSeekTo(&seekTimeUs, &seekMode)) {
99         // seek is needed
100         status_t err = mExtractor->seek(seekTimeUs, seekMode);
101         if (err != OK) {
102             return err;
103         }
104     }
105 
106     if (mExtractor->feedUntilBufferAvailable(mImpl) != OK) {
107         return ERROR_END_OF_STREAM;
108     }
109 
110     return mImpl->read(out, options);
111 }
112 
113 ////////////////////////////////////////////////////////////////////////////////
114 
MPEG2TSExtractor(const sp<DataSource> & source)115 MPEG2TSExtractor::MPEG2TSExtractor(const sp<DataSource> &source)
116     : mDataSource(source),
117       mParser(new ATSParser),
118       mLastSyncEvent(0),
119       mOffset(0) {
120     init();
121 }
122 
countTracks()123 size_t MPEG2TSExtractor::countTracks() {
124     return mSourceImpls.size();
125 }
126 
getTrack(size_t index)127 sp<IMediaSource> MPEG2TSExtractor::getTrack(size_t index) {
128     if (index >= mSourceImpls.size()) {
129         return NULL;
130     }
131 
132     // The seek reference track (video if present; audio otherwise) performs
133     // seek requests, while other tracks ignore requests.
134     return new MPEG2TSSource(this, mSourceImpls.editItemAt(index),
135             (mSeekSyncPoints == &mSyncPoints.editItemAt(index)));
136 }
137 
getTrackMetaData(size_t index,uint32_t)138 sp<MetaData> MPEG2TSExtractor::getTrackMetaData(
139         size_t index, uint32_t /* flags */) {
140     return index < mSourceImpls.size()
141         ? mSourceImpls.editItemAt(index)->getFormat() : NULL;
142 }
143 
getMetaData()144 sp<MetaData> MPEG2TSExtractor::getMetaData() {
145     sp<MetaData> meta = new MetaData;
146     meta->setCString(kKeyMIMEType, MEDIA_MIMETYPE_CONTAINER_MPEG2TS);
147 
148     return meta;
149 }
150 
151 //static
isScrambledFormat(const sp<MetaData> & format)152 bool MPEG2TSExtractor::isScrambledFormat(const sp<MetaData> &format) {
153     const char *mime;
154     return format->findCString(kKeyMIMEType, &mime)
155             && (!strcasecmp(MEDIA_MIMETYPE_VIDEO_SCRAMBLED, mime)
156                     || !strcasecmp(MEDIA_MIMETYPE_AUDIO_SCRAMBLED, mime));
157 }
158 
setMediaCas(const sp<ICas> & cas)159 status_t MPEG2TSExtractor::setMediaCas(const sp<ICas> &cas) {
160     ALOGD("setMediaCas: %p", cas.get());
161 
162     status_t err = mParser->setMediaCas(cas);
163     if (err == OK) {
164         ALOGI("All tracks now have descramblers");
165         init();
166     }
167     return err;
168 }
169 
addSource(const sp<AnotherPacketSource> & impl)170 void MPEG2TSExtractor::addSource(const sp<AnotherPacketSource> &impl) {
171     bool found = false;
172     for (size_t i = 0; i < mSourceImpls.size(); i++) {
173         if (mSourceImpls[i] == impl) {
174             found = true;
175             break;
176         }
177     }
178     if (!found) {
179         mSourceImpls.push(impl);
180     }
181 }
182 
init()183 void MPEG2TSExtractor::init() {
184     bool haveAudio = false;
185     bool haveVideo = false;
186     int64_t startTime = ALooper::GetNowUs();
187 
188     status_t err;
189     while ((err = feedMore(true /* isInit */)) == OK
190             || err == ERROR_DRM_DECRYPT_UNIT_NOT_INITIALIZED) {
191         if (haveAudio && haveVideo) {
192             addSyncPoint_l(mLastSyncEvent);
193             mLastSyncEvent.reset();
194             break;
195         }
196         if (!haveVideo) {
197             sp<AnotherPacketSource> impl =
198                 (AnotherPacketSource *)mParser->getSource(
199                         ATSParser::VIDEO).get();
200 
201             if (impl != NULL) {
202                 sp<MetaData> format = impl->getFormat();
203                 if (format != NULL) {
204                     haveVideo = true;
205                     addSource(impl);
206                     if (!isScrambledFormat(format)) {
207                         mSyncPoints.push();
208                         mSeekSyncPoints = &mSyncPoints.editTop();
209                     }
210                 }
211             }
212         }
213 
214         if (!haveAudio) {
215             sp<AnotherPacketSource> impl =
216                 (AnotherPacketSource *)mParser->getSource(
217                         ATSParser::AUDIO).get();
218 
219             if (impl != NULL) {
220                 sp<MetaData> format = impl->getFormat();
221                 if (format != NULL) {
222                     haveAudio = true;
223                     addSource(impl);
224                     if (!isScrambledFormat(format)) {
225                         mSyncPoints.push();
226                         if (!haveVideo) {
227                             mSeekSyncPoints = &mSyncPoints.editTop();
228                         }
229                     }
230                 }
231             }
232         }
233 
234         addSyncPoint_l(mLastSyncEvent);
235         mLastSyncEvent.reset();
236 
237         // ERROR_DRM_DECRYPT_UNIT_NOT_INITIALIZED is returned when the mpeg2ts
238         // is scrambled but we don't have a MediaCas object set. The extraction
239         // will only continue when setMediaCas() is called successfully.
240         if (err == ERROR_DRM_DECRYPT_UNIT_NOT_INITIALIZED) {
241             ALOGI("stopped parsing scrambled content, "
242                   "haveAudio=%d, haveVideo=%d, elaspedTime=%" PRId64,
243                     haveAudio, haveVideo, ALooper::GetNowUs() - startTime);
244             return;
245         }
246 
247         // Wait only for 2 seconds to detect audio/video streams.
248         if (ALooper::GetNowUs() - startTime > 2000000ll) {
249             break;
250         }
251     }
252 
253     off64_t size;
254     if (mDataSource->getSize(&size) == OK && (haveAudio || haveVideo)) {
255         sp<AnotherPacketSource> impl = haveVideo
256                 ? (AnotherPacketSource *)mParser->getSource(
257                         ATSParser::VIDEO).get()
258                 : (AnotherPacketSource *)mParser->getSource(
259                         ATSParser::AUDIO).get();
260         size_t prevSyncSize = 1;
261         int64_t durationUs = -1;
262         List<int64_t> durations;
263         // Estimate duration --- stabilize until you get <500ms deviation.
264         while (feedMore() == OK
265                 && ALooper::GetNowUs() - startTime <= 2000000ll) {
266             if (mSeekSyncPoints->size() > prevSyncSize) {
267                 prevSyncSize = mSeekSyncPoints->size();
268                 int64_t diffUs = mSeekSyncPoints->keyAt(prevSyncSize - 1)
269                         - mSeekSyncPoints->keyAt(0);
270                 off64_t diffOffset = mSeekSyncPoints->valueAt(prevSyncSize - 1)
271                         - mSeekSyncPoints->valueAt(0);
272                 int64_t currentDurationUs = size * diffUs / diffOffset;
273                 durations.push_back(currentDurationUs);
274                 if (durations.size() > 5) {
275                     durations.erase(durations.begin());
276                     int64_t min = *durations.begin();
277                     int64_t max = *durations.begin();
278                     for (auto duration : durations) {
279                         if (min > duration) {
280                             min = duration;
281                         }
282                         if (max < duration) {
283                             max = duration;
284                         }
285                     }
286                     if (max - min < 500 * 1000) {
287                         durationUs = currentDurationUs;
288                         break;
289                     }
290                 }
291             }
292         }
293         status_t err;
294         int64_t bufferedDurationUs;
295         bufferedDurationUs = impl->getBufferedDurationUs(&err);
296         if (err == ERROR_END_OF_STREAM) {
297             durationUs = bufferedDurationUs;
298         }
299         if (durationUs > 0) {
300             const sp<MetaData> meta = impl->getFormat();
301             meta->setInt64(kKeyDuration, durationUs);
302             impl->setFormat(meta);
303         } else {
304             estimateDurationsFromTimesUsAtEnd();
305         }
306     }
307 
308     ALOGI("haveAudio=%d, haveVideo=%d, elaspedTime=%" PRId64,
309             haveAudio, haveVideo, ALooper::GetNowUs() - startTime);
310 }
311 
feedMore(bool isInit)312 status_t MPEG2TSExtractor::feedMore(bool isInit) {
313     Mutex::Autolock autoLock(mLock);
314 
315     uint8_t packet[kTSPacketSize];
316     ssize_t n = mDataSource->readAt(mOffset, packet, kTSPacketSize);
317 
318     if (n < (ssize_t)kTSPacketSize) {
319         if (n >= 0) {
320             mParser->signalEOS(ERROR_END_OF_STREAM);
321         }
322         return (n < 0) ? (status_t)n : ERROR_END_OF_STREAM;
323     }
324 
325     ATSParser::SyncEvent event(mOffset);
326     mOffset += n;
327     status_t err = mParser->feedTSPacket(packet, kTSPacketSize, &event);
328     if (event.hasReturnedData()) {
329         if (isInit) {
330             mLastSyncEvent = event;
331         } else {
332             addSyncPoint_l(event);
333         }
334     }
335     return err;
336 }
337 
addSyncPoint_l(const ATSParser::SyncEvent & event)338 void MPEG2TSExtractor::addSyncPoint_l(const ATSParser::SyncEvent &event) {
339     if (!event.hasReturnedData()) {
340         return;
341     }
342 
343     for (size_t i = 0; i < mSourceImpls.size(); ++i) {
344         if (mSourceImpls[i].get() == event.getMediaSource().get()) {
345             KeyedVector<int64_t, off64_t> *syncPoints = &mSyncPoints.editItemAt(i);
346             syncPoints->add(event.getTimeUs(), event.getOffset());
347             // We're keeping the size of the sync points at most 5mb per a track.
348             size_t size = syncPoints->size();
349             if (size >= 327680) {
350                 int64_t firstTimeUs = syncPoints->keyAt(0);
351                 int64_t lastTimeUs = syncPoints->keyAt(size - 1);
352                 if (event.getTimeUs() - firstTimeUs > lastTimeUs - event.getTimeUs()) {
353                     syncPoints->removeItemsAt(0, 4096);
354                 } else {
355                     syncPoints->removeItemsAt(size - 4096, 4096);
356                 }
357             }
358             break;
359         }
360     }
361 }
362 
estimateDurationsFromTimesUsAtEnd()363 status_t MPEG2TSExtractor::estimateDurationsFromTimesUsAtEnd()  {
364     if (!(mDataSource->flags() & DataSource::kIsLocalFileSource)) {
365         return ERROR_UNSUPPORTED;
366     }
367 
368     off64_t size = 0;
369     status_t err = mDataSource->getSize(&size);
370     if (err != OK) {
371         return err;
372     }
373 
374     uint8_t packet[kTSPacketSize];
375     const off64_t zero = 0;
376     off64_t offset = max(zero, size - kMaxDurationReadSize);
377     if (mDataSource->readAt(offset, &packet, 0) < 0) {
378         return ERROR_IO;
379     }
380 
381     int retry = 0;
382     bool allDurationsFound = false;
383     int64_t timeAnchorUs = mParser->getFirstPTSTimeUs();
384     do {
385         int bytesRead = 0;
386         sp<ATSParser> parser = new ATSParser(ATSParser::TS_TIMESTAMPS_ARE_ABSOLUTE);
387         ATSParser::SyncEvent ev(0);
388         offset = max(zero, size - (kMaxDurationReadSize << retry));
389         offset = (offset / kTSPacketSize) * kTSPacketSize;
390         for (;;) {
391             if (bytesRead >= kMaxDurationReadSize << max(0, retry - 1)) {
392                 break;
393             }
394 
395             ssize_t n = mDataSource->readAt(offset, packet, kTSPacketSize);
396             if (n < 0) {
397                 return n;
398             } else if (n < (ssize_t)kTSPacketSize) {
399                 break;
400             }
401 
402             offset += kTSPacketSize;
403             bytesRead += kTSPacketSize;
404             err = parser->feedTSPacket(packet, kTSPacketSize, &ev);
405             if (err != OK) {
406                 return err;
407             }
408 
409             if (ev.hasReturnedData()) {
410                 int64_t durationUs = ev.getTimeUs();
411                 ATSParser::SourceType type = ev.getType();
412                 ev.reset();
413 
414                 int64_t firstTimeUs;
415                 sp<AnotherPacketSource> src =
416                     (AnotherPacketSource *)mParser->getSource(type).get();
417                 if (src == NULL || src->nextBufferTime(&firstTimeUs) != OK) {
418                     continue;
419                 }
420                 durationUs += src->getEstimatedBufferDurationUs();
421                 durationUs -= timeAnchorUs;
422                 durationUs -= firstTimeUs;
423                 if (durationUs > 0) {
424                     int64_t origDurationUs, lastDurationUs;
425                     const sp<MetaData> meta = src->getFormat();
426                     const uint32_t kKeyLastDuration = 'ldur';
427                     // Require two consecutive duration calculations to be within 1 sec before
428                     // updating; use MetaData to store previous duration estimate in per-stream
429                     // context.
430                     if (!meta->findInt64(kKeyDuration, &origDurationUs)
431                             || !meta->findInt64(kKeyLastDuration, &lastDurationUs)
432                             || (origDurationUs < durationUs
433                              && abs(durationUs - lastDurationUs) < 60000000)) {
434                         meta->setInt64(kKeyDuration, durationUs);
435                     }
436                     meta->setInt64(kKeyLastDuration, durationUs);
437                 }
438             }
439         }
440 
441         if (!allDurationsFound) {
442             allDurationsFound = true;
443             for (auto t: {ATSParser::VIDEO, ATSParser::AUDIO}) {
444                 sp<AnotherPacketSource> src = (AnotherPacketSource *)mParser->getSource(t).get();
445                 if (src == NULL) {
446                     continue;
447                 }
448                 int64_t durationUs;
449                 const sp<MetaData> meta = src->getFormat();
450                 if (!meta->findInt64(kKeyDuration, &durationUs)) {
451                     allDurationsFound = false;
452                     break;
453                 }
454             }
455         }
456 
457         ++retry;
458     } while(!allDurationsFound && offset > 0 && retry <= kMaxDurationRetry);
459 
460     return allDurationsFound? OK : ERROR_UNSUPPORTED;
461 }
462 
flags() const463 uint32_t MPEG2TSExtractor::flags() const {
464     return CAN_PAUSE | CAN_SEEK_BACKWARD | CAN_SEEK_FORWARD;
465 }
466 
seek(int64_t seekTimeUs,const MediaSource::ReadOptions::SeekMode & seekMode)467 status_t MPEG2TSExtractor::seek(int64_t seekTimeUs,
468         const MediaSource::ReadOptions::SeekMode &seekMode) {
469     if (mSeekSyncPoints == NULL || mSeekSyncPoints->isEmpty()) {
470         ALOGW("No sync point to seek to.");
471         // ... and therefore we have nothing useful to do here.
472         return OK;
473     }
474 
475     // Determine whether we're seeking beyond the known area.
476     bool shouldSeekBeyond =
477             (seekTimeUs > mSeekSyncPoints->keyAt(mSeekSyncPoints->size() - 1));
478 
479     // Determine the sync point to seek.
480     size_t index = 0;
481     for (; index < mSeekSyncPoints->size(); ++index) {
482         int64_t timeUs = mSeekSyncPoints->keyAt(index);
483         if (timeUs > seekTimeUs) {
484             break;
485         }
486     }
487 
488     switch (seekMode) {
489         case MediaSource::ReadOptions::SEEK_NEXT_SYNC:
490             if (index == mSeekSyncPoints->size()) {
491                 ALOGW("Next sync not found; starting from the latest sync.");
492                 --index;
493             }
494             break;
495         case MediaSource::ReadOptions::SEEK_CLOSEST_SYNC:
496         case MediaSource::ReadOptions::SEEK_CLOSEST:
497             ALOGW("seekMode not supported: %d; falling back to PREVIOUS_SYNC",
498                     seekMode);
499             // fall-through
500         case MediaSource::ReadOptions::SEEK_PREVIOUS_SYNC:
501             if (index == 0) {
502                 ALOGW("Previous sync not found; starting from the earliest "
503                         "sync.");
504             } else {
505                 --index;
506             }
507             break;
508     }
509     if (!shouldSeekBeyond || mOffset <= mSeekSyncPoints->valueAt(index)) {
510         int64_t actualSeekTimeUs = mSeekSyncPoints->keyAt(index);
511         mOffset = mSeekSyncPoints->valueAt(index);
512         status_t err = queueDiscontinuityForSeek(actualSeekTimeUs);
513         if (err != OK) {
514             return err;
515         }
516     }
517 
518     if (shouldSeekBeyond) {
519         status_t err = seekBeyond(seekTimeUs);
520         if (err != OK) {
521             return err;
522         }
523     }
524 
525     // Fast-forward to sync frame.
526     for (size_t i = 0; i < mSourceImpls.size(); ++i) {
527         const sp<AnotherPacketSource> &impl = mSourceImpls[i];
528         status_t err;
529         feedUntilBufferAvailable(impl);
530         while (impl->hasBufferAvailable(&err)) {
531             sp<AMessage> meta = impl->getMetaAfterLastDequeued(0);
532             sp<ABuffer> buffer;
533             if (meta == NULL) {
534                 return UNKNOWN_ERROR;
535             }
536             int32_t sync;
537             if (meta->findInt32("isSync", &sync) && sync) {
538                 break;
539             }
540             err = impl->dequeueAccessUnit(&buffer);
541             if (err != OK) {
542                 return err;
543             }
544             feedUntilBufferAvailable(impl);
545         }
546     }
547 
548     return OK;
549 }
550 
queueDiscontinuityForSeek(int64_t actualSeekTimeUs)551 status_t MPEG2TSExtractor::queueDiscontinuityForSeek(int64_t actualSeekTimeUs) {
552     // Signal discontinuity
553     sp<AMessage> extra(new AMessage);
554     extra->setInt64(IStreamListener::kKeyMediaTimeUs, actualSeekTimeUs);
555     mParser->signalDiscontinuity(ATSParser::DISCONTINUITY_TIME, extra);
556 
557     // After discontinuity, impl should only have discontinuities
558     // with the last being what we queued. Dequeue them all here.
559     for (size_t i = 0; i < mSourceImpls.size(); ++i) {
560         const sp<AnotherPacketSource> &impl = mSourceImpls.itemAt(i);
561         sp<ABuffer> buffer;
562         status_t err;
563         while (impl->hasBufferAvailable(&err)) {
564             if (err != OK) {
565                 return err;
566             }
567             err = impl->dequeueAccessUnit(&buffer);
568             // If the source contains anything but discontinuity, that's
569             // a programming mistake.
570             CHECK(err == INFO_DISCONTINUITY);
571         }
572     }
573 
574     // Feed until we have a buffer for each source.
575     for (size_t i = 0; i < mSourceImpls.size(); ++i) {
576         const sp<AnotherPacketSource> &impl = mSourceImpls.itemAt(i);
577         sp<ABuffer> buffer;
578         status_t err = feedUntilBufferAvailable(impl);
579         if (err != OK) {
580             return err;
581         }
582     }
583 
584     return OK;
585 }
586 
seekBeyond(int64_t seekTimeUs)587 status_t MPEG2TSExtractor::seekBeyond(int64_t seekTimeUs) {
588     // If we're seeking beyond where we know --- read until we reach there.
589     size_t syncPointsSize = mSeekSyncPoints->size();
590 
591     while (seekTimeUs > mSeekSyncPoints->keyAt(
592             mSeekSyncPoints->size() - 1)) {
593         status_t err;
594         if (syncPointsSize < mSeekSyncPoints->size()) {
595             syncPointsSize = mSeekSyncPoints->size();
596             int64_t syncTimeUs = mSeekSyncPoints->keyAt(syncPointsSize - 1);
597             // Dequeue buffers before sync point in order to avoid too much
598             // cache building up.
599             sp<ABuffer> buffer;
600             for (size_t i = 0; i < mSourceImpls.size(); ++i) {
601                 const sp<AnotherPacketSource> &impl = mSourceImpls[i];
602                 int64_t timeUs;
603                 while ((err = impl->nextBufferTime(&timeUs)) == OK) {
604                     if (timeUs < syncTimeUs) {
605                         impl->dequeueAccessUnit(&buffer);
606                     } else {
607                         break;
608                     }
609                 }
610                 if (err != OK && err != -EWOULDBLOCK) {
611                     return err;
612                 }
613             }
614         }
615         if (feedMore() != OK) {
616             return ERROR_END_OF_STREAM;
617         }
618     }
619 
620     return OK;
621 }
622 
feedUntilBufferAvailable(const sp<AnotherPacketSource> & impl)623 status_t MPEG2TSExtractor::feedUntilBufferAvailable(
624         const sp<AnotherPacketSource> &impl) {
625     status_t finalResult;
626     while (!impl->hasBufferAvailable(&finalResult)) {
627         if (finalResult != OK) {
628             return finalResult;
629         }
630 
631         status_t err = feedMore();
632         if (err != OK) {
633             impl->signalEOS(err);
634         }
635     }
636     return OK;
637 }
638 
639 ////////////////////////////////////////////////////////////////////////////////
640 
SniffMPEG2TS(const sp<DataSource> & source,String8 * mimeType,float * confidence,sp<AMessage> *)641 bool SniffMPEG2TS(
642         const sp<DataSource> &source, String8 *mimeType, float *confidence,
643         sp<AMessage> *) {
644     for (int i = 0; i < 5; ++i) {
645         char header;
646         if (source->readAt(kTSPacketSize * i, &header, 1) != 1
647                 || header != 0x47) {
648             return false;
649         }
650     }
651 
652     *confidence = 0.1f;
653     mimeType->setTo(MEDIA_MIMETYPE_CONTAINER_MPEG2TS);
654 
655     return true;
656 }
657 
658 }  // namespace android
659