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1 /*
2  * Copyright (C) 2012 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 package android.media;
18 
19 import android.annotation.IntDef;
20 import android.annotation.NonNull;
21 import android.annotation.Nullable;
22 import android.content.ContentResolver;
23 import android.content.Context;
24 import android.content.res.AssetFileDescriptor;
25 import android.media.metrics.LogSessionId;
26 import android.net.Uri;
27 import android.os.IBinder;
28 import android.os.IHwBinder;
29 import android.os.PersistableBundle;
30 
31 import com.android.internal.util.Preconditions;
32 
33 import java.io.FileDescriptor;
34 import java.io.IOException;
35 import java.lang.annotation.Retention;
36 import java.lang.annotation.RetentionPolicy;
37 import java.nio.ByteBuffer;
38 import java.nio.ByteOrder;
39 import java.util.Arrays;
40 import java.util.HashMap;
41 import java.util.List;
42 import java.util.Map;
43 import java.util.Objects;
44 import java.util.UUID;
45 import java.util.stream.Collectors;
46 
47 /**
48  * MediaExtractor facilitates extraction of demuxed, typically encoded,  media data
49  * from a data source.
50  * <p>It is generally used like this:
51  * <pre>
52  * MediaExtractor extractor = new MediaExtractor();
53  * extractor.setDataSource(...);
54  * int numTracks = extractor.getTrackCount();
55  * for (int i = 0; i &lt; numTracks; ++i) {
56  *   MediaFormat format = extractor.getTrackFormat(i);
57  *   String mime = format.getString(MediaFormat.KEY_MIME);
58  *   if (weAreInterestedInThisTrack) {
59  *     extractor.selectTrack(i);
60  *   }
61  * }
62  * ByteBuffer inputBuffer = ByteBuffer.allocate(...)
63  * while (extractor.readSampleData(inputBuffer, ...) &gt;= 0) {
64  *   int trackIndex = extractor.getSampleTrackIndex();
65  *   long presentationTimeUs = extractor.getSampleTime();
66  *   ...
67  *   extractor.advance();
68  * }
69  *
70  * extractor.release();
71  * extractor = null;
72  * </pre>
73  *
74  * <p>This class requires the {@link android.Manifest.permission#INTERNET} permission
75  * when used with network-based content.
76  */
77 public final class MediaExtractor {
MediaExtractor()78     public MediaExtractor() {
79         native_setup();
80     }
81 
82     /**
83      * Sets the data source (MediaDataSource) to use.
84      *
85      * @param dataSource the MediaDataSource for the media you want to extract from
86      *
87      * @throws IllegalArgumentException if dataSource is invalid.
88      */
setDataSource(@onNull MediaDataSource dataSource)89     public native final void setDataSource(@NonNull MediaDataSource dataSource)
90         throws IOException;
91 
92     /**
93      * Sets the data source as a content Uri.
94      *
95      * @param context the Context to use when resolving the Uri
96      * @param uri the Content URI of the data you want to extract from.
97      *
98      * <p>When <code>uri</code> refers to a network file the
99      * {@link android.Manifest.permission#INTERNET} permission is required.
100      *
101      * @param headers the headers to be sent together with the request for the data.
102      *        This can be {@code null} if no specific headers are to be sent with the
103      *        request.
104      */
setDataSource( @onNull Context context, @NonNull Uri uri, @Nullable Map<String, String> headers)105     public final void setDataSource(
106             @NonNull Context context, @NonNull Uri uri, @Nullable Map<String, String> headers)
107         throws IOException {
108         String scheme = uri.getScheme();
109         if (scheme == null || scheme.equals("file")) {
110             setDataSource(uri.getPath());
111             return;
112         }
113 
114         AssetFileDescriptor fd = null;
115         try {
116             ContentResolver resolver = context.getContentResolver();
117             fd = resolver.openAssetFileDescriptor(uri, "r");
118             if (fd == null) {
119                 return;
120             }
121             // Note: using getDeclaredLength so that our behavior is the same
122             // as previous versions when the content provider is returning
123             // a full file.
124             if (fd.getDeclaredLength() < 0) {
125                 setDataSource(fd.getFileDescriptor());
126             } else {
127                 setDataSource(
128                         fd.getFileDescriptor(),
129                         fd.getStartOffset(),
130                         fd.getDeclaredLength());
131             }
132             return;
133         } catch (SecurityException ex) {
134         } catch (IOException ex) {
135         } finally {
136             if (fd != null) {
137                 fd.close();
138             }
139         }
140 
141         setDataSource(uri.toString(), headers);
142     }
143 
144     /**
145      * Sets the data source (file-path or http URL) to use.
146      *
147      * @param path the path of the file, or the http URL
148      *
149      * <p>When <code>path</code> refers to a network file the
150      * {@link android.Manifest.permission#INTERNET} permission is required.
151      *
152      * @param headers the headers associated with the http request for the stream you want to play.
153      *        This can be {@code null} if no specific headers are to be sent with the
154      *        request.
155      */
setDataSource(@onNull String path, @Nullable Map<String, String> headers)156     public final void setDataSource(@NonNull String path, @Nullable Map<String, String> headers)
157         throws IOException {
158         String[] keys = null;
159         String[] values = null;
160 
161         if (headers != null) {
162             keys = new String[headers.size()];
163             values = new String[headers.size()];
164 
165             int i = 0;
166             for (Map.Entry<String, String> entry: headers.entrySet()) {
167                 keys[i] = entry.getKey();
168                 values[i] = entry.getValue();
169                 ++i;
170             }
171         }
172 
173         nativeSetDataSource(
174                 MediaHTTPService.createHttpServiceBinderIfNecessary(path),
175                 path,
176                 keys,
177                 values);
178     }
179 
nativeSetDataSource( @onNull IBinder httpServiceBinder, @NonNull String path, @Nullable String[] keys, @Nullable String[] values)180     private native final void nativeSetDataSource(
181             @NonNull IBinder httpServiceBinder,
182             @NonNull String path,
183             @Nullable String[] keys,
184             @Nullable String[] values) throws IOException;
185 
186     /**
187      * Sets the data source (file-path or http URL) to use.
188      *
189      * @param path the path of the file, or the http URL of the stream
190      *
191      * <p>When <code>path</code> refers to a local file, the file may actually be opened by a
192      * process other than the calling application.  This implies that the pathname
193      * should be an absolute path (as any other process runs with unspecified current working
194      * directory), and that the pathname should reference a world-readable file.
195      * As an alternative, the application could first open the file for reading,
196      * and then use the file descriptor form {@link #setDataSource(FileDescriptor)}.
197      *
198      * <p>When <code>path</code> refers to a network file the
199      * {@link android.Manifest.permission#INTERNET} permission is required.
200      */
setDataSource(@onNull String path)201     public final void setDataSource(@NonNull String path) throws IOException {
202         nativeSetDataSource(
203                 MediaHTTPService.createHttpServiceBinderIfNecessary(path),
204                 path,
205                 null,
206                 null);
207     }
208 
209     /**
210      * Sets the data source (AssetFileDescriptor) to use. It is the caller's
211      * responsibility to close the file descriptor. It is safe to do so as soon
212      * as this call returns.
213      *
214      * @param afd the AssetFileDescriptor for the file you want to extract from.
215      */
setDataSource(@onNull AssetFileDescriptor afd)216     public final void setDataSource(@NonNull AssetFileDescriptor afd)
217             throws IOException, IllegalArgumentException, IllegalStateException {
218         Preconditions.checkNotNull(afd);
219         // Note: using getDeclaredLength so that our behavior is the same
220         // as previous versions when the content provider is returning
221         // a full file.
222         if (afd.getDeclaredLength() < 0) {
223             setDataSource(afd.getFileDescriptor());
224         } else {
225             setDataSource(afd.getFileDescriptor(), afd.getStartOffset(), afd.getDeclaredLength());
226         }
227     }
228 
229     /**
230      * Sets the data source (FileDescriptor) to use. It is the caller's responsibility
231      * to close the file descriptor. It is safe to do so as soon as this call returns.
232      *
233      * @param fd the FileDescriptor for the file you want to extract from.
234      */
setDataSource(@onNull FileDescriptor fd)235     public final void setDataSource(@NonNull FileDescriptor fd) throws IOException {
236         setDataSource(fd, 0, 0x7ffffffffffffffL);
237     }
238 
239     /**
240      * Sets the data source (FileDescriptor) to use.  The FileDescriptor must be
241      * seekable (N.B. a LocalSocket is not seekable). It is the caller's responsibility
242      * to close the file descriptor. It is safe to do so as soon as this call returns.
243      *
244      * @param fd the FileDescriptor for the file you want to extract from.
245      * @param offset the offset into the file where the data to be extracted starts, in bytes
246      * @param length the length in bytes of the data to be extracted
247      */
setDataSource( @onNull FileDescriptor fd, long offset, long length)248     public native final void setDataSource(
249             @NonNull FileDescriptor fd, long offset, long length) throws IOException;
250 
251     /**
252      * Sets the MediaCas instance to use. This should be called after a successful setDataSource()
253      * if at least one track reports mime type of
254      * {@link android.media.MediaFormat#MIMETYPE_AUDIO_SCRAMBLED} or
255      * {@link android.media.MediaFormat#MIMETYPE_VIDEO_SCRAMBLED}. Stream parsing will not proceed
256      * until a valid MediaCas object is provided.
257      *
258      * @param mediaCas the MediaCas object to use.
259      * @deprecated Use the {@code Descrambler} system API instead, or DRM public APIs like
260      *             {@link MediaDrm}.
261      */
262     @Deprecated
setMediaCas(@onNull MediaCas mediaCas)263     public final void setMediaCas(@NonNull MediaCas mediaCas) {
264         mMediaCas = mediaCas;
265         nativeSetMediaCas(mediaCas.getBinder());
266     }
267 
nativeSetMediaCas(@onNull IHwBinder casBinder)268     private native final void nativeSetMediaCas(@NonNull IHwBinder casBinder);
269 
270     /**
271      * Describes the conditional access system used to scramble a track.
272      */
273     public static final class CasInfo {
274         private final int mSystemId;
275         private final MediaCas.Session mSession;
276         private final byte[] mPrivateData;
277 
CasInfo(int systemId, @Nullable MediaCas.Session session, @Nullable byte[] privateData)278         CasInfo(int systemId, @Nullable MediaCas.Session session, @Nullable byte[] privateData) {
279             mSystemId = systemId;
280             mSession = session;
281             mPrivateData = privateData;
282         }
283 
284         /**
285          * Retrieves the system id of the conditional access system.
286          *
287          * @return CA system id of the CAS used to scramble the track.
288          */
getSystemId()289         public int getSystemId() {
290             return mSystemId;
291         }
292 
293         /**
294          * Retrieves the private data in the CA_Descriptor associated with a track.
295          * Some CAS systems may need this to initialize the CAS plugin object. This
296          * private data can only be retrieved before a valid {@link MediaCas} object
297          * is set on the extractor.
298          * <p>
299          * @see MediaExtractor#setMediaCas
300          * <p>
301          * @return a byte array containing the private data. A null return value
302          *         indicates that the private data is unavailable. An empty array,
303          *         on the other hand, indicates that the private data is empty
304          *         (zero in length).
305          */
306         @Nullable
getPrivateData()307         public byte[] getPrivateData() {
308             return mPrivateData;
309         }
310 
311         /**
312          * Retrieves the {@link MediaCas.Session} associated with a track. The
313          * session is needed to initialize a descrambler in order to decode the
314          * scrambled track. The session object can only be retrieved after a valid
315          * {@link MediaCas} object is set on the extractor.
316          * <p>
317          * @see MediaExtractor#setMediaCas
318          * @see MediaDescrambler#setMediaCasSession
319          * <p>
320          * @return a {@link MediaCas.Session} object associated with a track.
321          */
getSession()322         public MediaCas.Session getSession() {
323             return mSession;
324         }
325     }
326 
327     /**
328      * Retrieves the information about the conditional access system used to scramble
329      * a track.
330      *
331      * @param index of the track.
332      * @return an {@link CasInfo} object describing the conditional access system.
333      */
getCasInfo(int index)334     public CasInfo getCasInfo(int index) {
335         Map<String, Object> formatMap = getTrackFormatNative(index);
336         if (formatMap.containsKey(MediaFormat.KEY_CA_SYSTEM_ID)) {
337             int systemId = ((Integer)formatMap.get(MediaFormat.KEY_CA_SYSTEM_ID)).intValue();
338             MediaCas.Session session = null;
339             byte[] privateData = null;
340             if (formatMap.containsKey(MediaFormat.KEY_CA_PRIVATE_DATA)) {
341                 ByteBuffer buf = (ByteBuffer) formatMap.get(MediaFormat.KEY_CA_PRIVATE_DATA);
342                 buf.rewind();
343                 privateData = new byte[buf.remaining()];
344                 buf.get(privateData);
345             }
346             if (mMediaCas != null && formatMap.containsKey(MediaFormat.KEY_CA_SESSION_ID)) {
347                 ByteBuffer buf = (ByteBuffer) formatMap.get(MediaFormat.KEY_CA_SESSION_ID);
348                 buf.rewind();
349                 final byte[] sessionId = new byte[buf.remaining()];
350                 buf.get(sessionId);
351                 session = mMediaCas.createFromSessionId(sessionId);
352             }
353             return new CasInfo(systemId, session, privateData);
354         }
355         return null;
356     }
357 
358     @Override
finalize()359     protected void finalize() {
360         native_finalize();
361     }
362 
363     /**
364      * Make sure you call this when you're done to free up any resources
365      * instead of relying on the garbage collector to do this for you at
366      * some point in the future.
367      */
release()368     public native final void release();
369 
370     /**
371      * Count the number of tracks found in the data source.
372      */
getTrackCount()373     public native final int getTrackCount();
374 
375     /**
376      * Extract DRM initialization data if it exists
377      *
378      * <p>If the media contains a PSSH box, only PSSH version 0 is supported. The result for media
379      * with other PSSH versions is undefined.
380      *
381      * @return DRM initialization data in the content, or {@code null}
382      * if no recognizable DRM format is found;
383      * @see DrmInitData
384      */
getDrmInitData()385     public DrmInitData getDrmInitData() {
386         Map<String, Object> formatMap = getFileFormatNative();
387         if (formatMap == null) {
388             return null;
389         }
390         if (formatMap.containsKey("pssh")) {
391             Map<UUID, byte[]> psshMap = getPsshInfo();
392             DrmInitData.SchemeInitData[] schemeInitDatas =
393                     psshMap.entrySet().stream().map(
394                             entry -> new DrmInitData.SchemeInitData(
395                                     entry.getKey(), /* mimeType= */ "cenc", entry.getValue()))
396                             .toArray(DrmInitData.SchemeInitData[]::new);
397             final Map<UUID, DrmInitData.SchemeInitData> initDataMap =
398                     Arrays.stream(schemeInitDatas).collect(
399                             Collectors.toMap(initData -> initData.uuid, initData -> initData));
400             return new DrmInitData() {
401                 public SchemeInitData get(UUID schemeUuid) {
402                     return initDataMap.get(schemeUuid);
403                 }
404 
405                 @Override
406                 public int getSchemeInitDataCount() {
407                     return schemeInitDatas.length;
408                 }
409 
410                 @Override
411                 public SchemeInitData getSchemeInitDataAt(int index) {
412                     return schemeInitDatas[index];
413                 }
414             };
415         } else {
416             int numTracks = getTrackCount();
417             for (int i = 0; i < numTracks; ++i) {
418                 Map<String, Object> trackFormatMap = getTrackFormatNative(i);
419                 if (!trackFormatMap.containsKey("crypto-key")) {
420                     continue;
421                 }
422                 ByteBuffer buf = (ByteBuffer) trackFormatMap.get("crypto-key");
423                 buf.rewind();
424                 final byte[] data = new byte[buf.remaining()];
425                 buf.get(data);
426                 // Webm scheme init data is not uuid-specific.
427                 DrmInitData.SchemeInitData webmSchemeInitData =
428                         new DrmInitData.SchemeInitData(
429                                 DrmInitData.SchemeInitData.UUID_NIL, "webm", data);
430                 return new DrmInitData() {
431                     public SchemeInitData get(UUID schemeUuid) {
432                         return webmSchemeInitData;
433                     }
434 
435                     @Override
436                     public int getSchemeInitDataCount() {
437                         return 1;
438                     }
439 
440                     @Override
441                     public SchemeInitData getSchemeInitDataAt(int index) {
442                         return webmSchemeInitData;
443                     }
444                 };
445             }
446         }
447         return null;
448     }
449 
450     /**
451      * Get the list of available audio presentations for the track.
452      * @param trackIndex index of the track.
453      * @return a list of available audio presentations for a given valid audio track index.
454      * The list will be empty if the source does not contain any audio presentations.
455      */
456     @NonNull
457     public List<AudioPresentation> getAudioPresentations(int trackIndex) {
458         return native_getAudioPresentations(trackIndex);
459     }
460 
461     @NonNull
462     private native List<AudioPresentation> native_getAudioPresentations(int trackIndex);
463 
464     /**
465      * Get the PSSH info if present.
466      *
467      * <p>This method only supports version 0 PSSH boxes. The result for other versions is
468      * undefined.
469      *
470      * @return a map of uuid-to-bytes, with the uuid specifying
471      * the crypto scheme, and the bytes being the data specific to that scheme.
472      * This can be {@code null} if the source does not contain PSSH info.
473      */
474     @Nullable
475     public Map<UUID, byte[]> getPsshInfo() {
476         Map<UUID, byte[]> psshMap = null;
477         Map<String, Object> formatMap = getFileFormatNative();
478         if (formatMap != null && formatMap.containsKey("pssh")) {
479             ByteBuffer rawpssh = (ByteBuffer) formatMap.get("pssh");
480             rawpssh.order(ByteOrder.nativeOrder());
481             rawpssh.rewind();
482             formatMap.remove("pssh");
483             // parse the flat pssh bytebuffer into something more manageable
484             psshMap = new HashMap<UUID, byte[]>();
485             while (rawpssh.remaining() > 0) {
486                 rawpssh.order(ByteOrder.BIG_ENDIAN);
487                 long msb = rawpssh.getLong();
488                 long lsb = rawpssh.getLong();
489                 UUID uuid = new UUID(msb, lsb);
490                 rawpssh.order(ByteOrder.nativeOrder());
491                 int datalen = rawpssh.getInt();
492                 byte [] psshdata = new byte[datalen];
493                 rawpssh.get(psshdata);
494                 psshMap.put(uuid, psshdata);
495             }
496         }
497         return psshMap;
498     }
499 
500     @NonNull
501     private native Map<String, Object> getFileFormatNative();
502 
503     /**
504      * Get the track format at the specified index.
505      *
506      * More detail on the representation can be found at {@link android.media.MediaCodec}
507      * <p>
508      * The following table summarizes support for format keys across android releases:
509      *
510      * <table style="width: 0%">
511      *  <thead>
512      *   <tr>
513      *    <th rowspan=2>OS Version(s)</th>
514      *    <td colspan=3>{@code MediaFormat} keys used for</th>
515      *   </tr><tr>
516      *    <th>All Tracks</th>
517      *    <th>Audio Tracks</th>
518      *    <th>Video Tracks</th>
519      *   </tr>
520      *  </thead>
521      *  <tbody>
522      *   <tr>
523      *    <td>{@link android.os.Build.VERSION_CODES#JELLY_BEAN}</td>
524      *    <td rowspan=8>{@link MediaFormat#KEY_MIME},<br>
525      *        {@link MediaFormat#KEY_DURATION},<br>
526      *        {@link MediaFormat#KEY_MAX_INPUT_SIZE}</td>
527      *    <td rowspan=5>{@link MediaFormat#KEY_SAMPLE_RATE},<br>
528      *        {@link MediaFormat#KEY_CHANNEL_COUNT},<br>
529      *        {@link MediaFormat#KEY_CHANNEL_MASK},<br>
530      *        gapless playback information<sup>.mp3, .mp4</sup>,<br>
531      *        {@link MediaFormat#KEY_IS_ADTS}<sup>AAC if streaming</sup>,<br>
532      *        codec-specific data<sup>AAC, Vorbis</sup></td>
533      *    <td rowspan=2>{@link MediaFormat#KEY_WIDTH},<br>
534      *        {@link MediaFormat#KEY_HEIGHT},<br>
535      *        codec-specific data<sup>AVC, MPEG4</sup></td>
536      *   </tr><tr>
537      *    <td>{@link android.os.Build.VERSION_CODES#JELLY_BEAN_MR1}</td>
538      *   </tr><tr>
539      *    <td>{@link android.os.Build.VERSION_CODES#JELLY_BEAN_MR2}</td>
540      *    <td rowspan=3>as above, plus<br>
541      *        Pixel aspect ratio information<sup>AVC, *</sup></td>
542      *   </tr><tr>
543      *    <td>{@link android.os.Build.VERSION_CODES#KITKAT}</td>
544      *   </tr><tr>
545      *    <td>{@link android.os.Build.VERSION_CODES#KITKAT_WATCH}</td>
546      *   </tr><tr>
547      *    <td>{@link android.os.Build.VERSION_CODES#LOLLIPOP}</td>
548      *    <td rowspan=2>as above, plus<br>
549      *        {@link MediaFormat#KEY_BIT_RATE}<sup>AAC</sup>,<br>
550      *        codec-specific data<sup>Opus</sup></td>
551      *    <td rowspan=2>as above, plus<br>
552      *        {@link MediaFormat#KEY_ROTATION}<sup>.mp4</sup>,<br>
553      *        {@link MediaFormat#KEY_BIT_RATE}<sup>MPEG4</sup>,<br>
554      *        codec-specific data<sup>HEVC</sup></td>
555      *   </tr><tr>
556      *    <td>{@link android.os.Build.VERSION_CODES#LOLLIPOP_MR1}</td>
557      *   </tr><tr>
558      *    <td>{@link android.os.Build.VERSION_CODES#M}</td>
559      *    <td>as above, plus<br>
560      *        gapless playback information<sup>Opus</sup></td>
561      *    <td>as above, plus<br>
562      *        {@link MediaFormat#KEY_FRAME_RATE} (integer)</td>
563      *   </tr><tr>
564      *    <td>{@link android.os.Build.VERSION_CODES#N}</td>
565      *    <td>as above, plus<br>
566      *        {@link MediaFormat#KEY_TRACK_ID},<br>
567      *        <!-- {link MediaFormat#KEY_MAX_BIT_RATE}<sup>#, .mp4</sup>,<br> -->
568      *        {@link MediaFormat#KEY_BIT_RATE}<sup>#, .mp4</sup></td>
569      *    <td>as above, plus<br>
570      *        {@link MediaFormat#KEY_PCM_ENCODING},<br>
571      *        {@link MediaFormat#KEY_PROFILE}<sup>AAC</sup></td>
572      *    <td>as above, plus<br>
573      *        {@link MediaFormat#KEY_HDR_STATIC_INFO}<sup>#, .webm</sup>,<br>
574      *        {@link MediaFormat#KEY_COLOR_STANDARD}<sup>#</sup>,<br>
575      *        {@link MediaFormat#KEY_COLOR_TRANSFER}<sup>#</sup>,<br>
576      *        {@link MediaFormat#KEY_COLOR_RANGE}<sup>#</sup>,<br>
577      *        {@link MediaFormat#KEY_PROFILE}<sup>MPEG2, H.263, MPEG4, AVC, HEVC, VP9</sup>,<br>
578      *        {@link MediaFormat#KEY_LEVEL}<sup>H.263, MPEG4, AVC, HEVC, VP9</sup>,<br>
579      *        codec-specific data<sup>VP9</sup></td>
580      *   </tr>
581      *   <tr>
582      *    <td colspan=4>
583      *     <p class=note><strong>Notes:</strong><br>
584      *      #: container-specified value only.<br>
585      *      .mp4, .webm&hellip;: for listed containers<br>
586      *      MPEG4, AAC&hellip;: for listed codecs
587      *    </td>
588      *   </tr><tr>
589      *    <td colspan=4>
590      *     <p class=note>Note that that level information contained in the container many times
591      *     does not match the level of the actual bitstream. You may want to clear the level using
592      *     {@code MediaFormat.setString(KEY_LEVEL, null)} before using the track format to find a
593      *     decoder that can play back a particular track.
594      *    </td>
595      *   </tr><tr>
596      *    <td colspan=4>
597      *     <p class=note><strong>*Pixel (sample) aspect ratio</strong> is returned in the following
598      *     keys. The display width can be calculated for example as:
599      *     <p align=center>
600      *     display-width = display-height * crop-width / crop-height * sar-width / sar-height
601      *    </td>
602      *   </tr><tr>
603      *    <th>Format Key</th><th>Value Type</th><th colspan=2>Description</th>
604      *   </tr><tr>
605      *    <td>{@code "sar-width"}</td><td>Integer</td><td colspan=2>Pixel aspect ratio width</td>
606      *   </tr><tr>
607      *    <td>{@code "sar-height"}</td><td>Integer</td><td colspan=2>Pixel aspect ratio height</td>
608      *   </tr>
609      *  </tbody>
610      * </table>
611      *
612      */
613     @NonNull
614     public MediaFormat getTrackFormat(int index) {
615         return new MediaFormat(getTrackFormatNative(index));
616     }
617 
618     @NonNull
619     private native Map<String, Object> getTrackFormatNative(int index);
620 
621     /**
622      * Subsequent calls to {@link #readSampleData}, {@link #getSampleTrackIndex} and
623      * {@link #getSampleTime} only retrieve information for the subset of tracks
624      * selected.
625      * Selecting the same track multiple times has no effect, the track is
626      * only selected once.
627      */
628     public native void selectTrack(int index);
629 
630     /**
631      * Subsequent calls to {@link #readSampleData}, {@link #getSampleTrackIndex} and
632      * {@link #getSampleTime} only retrieve information for the subset of tracks
633      * selected.
634      */
635     public native void unselectTrack(int index);
636 
637     /**
638      * If possible, seek to a sync sample at or before the specified time
639      */
640     public static final int SEEK_TO_PREVIOUS_SYNC       = 0;
641     /**
642      * If possible, seek to a sync sample at or after the specified time
643      */
644     public static final int SEEK_TO_NEXT_SYNC           = 1;
645     /**
646      * If possible, seek to the sync sample closest to the specified time
647      */
648     public static final int SEEK_TO_CLOSEST_SYNC        = 2;
649 
650     /** @hide */
651     @IntDef({
652         SEEK_TO_PREVIOUS_SYNC,
653         SEEK_TO_NEXT_SYNC,
654         SEEK_TO_CLOSEST_SYNC,
655     })
656     @Retention(RetentionPolicy.SOURCE)
657     public @interface SeekMode {}
658 
659     /**
660      * All selected tracks seek near the requested time according to the
661      * specified mode.
662      */
663     public native void seekTo(long timeUs, @SeekMode int mode);
664 
665     /**
666      * Advance to the next sample. Returns false if no more sample data
667      * is available (end of stream).
668      *
669      * When extracting a local file, the behaviors of {@link #advance} and
670      * {@link #readSampleData} are undefined in presence of concurrent
671      * writes to the same local file; more specifically, end of stream
672      * could be signalled earlier than expected.
673      */
674     public native boolean advance();
675 
676     /**
677      * Retrieve the current encoded sample and store it in the byte buffer
678      * starting at the given offset.
679      * <p>
680      * <b>Note:</b>As of API 21, on success the position and limit of
681      * {@code byteBuf} is updated to point to the data just read.
682      * @param byteBuf the destination byte buffer
683      * @return the sample size (or -1 if no more samples are available).
684      */
685     public native int readSampleData(@NonNull ByteBuffer byteBuf, int offset);
686 
687     /**
688      * Returns the track index the current sample originates from (or -1
689      * if no more samples are available)
690      */
691     public native int getSampleTrackIndex();
692 
693     /**
694      * Returns the current sample's presentation time in microseconds.
695      * or -1 if no more samples are available.
696      */
697     public native long getSampleTime();
698 
699     /**
700      * @return size of the current sample in bytes or -1 if no more
701      * samples are available.
702      */
703     public native long getSampleSize();
704 
705     // Keep these in sync with their equivalents in NuMediaExtractor.h
706     /**
707      * The sample is a sync sample (or in {@link MediaCodec}'s terminology
708      * it is a key frame.)
709      *
710      * @see MediaCodec#BUFFER_FLAG_KEY_FRAME
711      */
712     public static final int SAMPLE_FLAG_SYNC      = 1;
713 
714     /**
715      * The sample is (at least partially) encrypted, see also the documentation
716      * for {@link android.media.MediaCodec#queueSecureInputBuffer}
717      */
718     public static final int SAMPLE_FLAG_ENCRYPTED = 2;
719 
720     /**
721      * This indicates that the buffer only contains part of a frame,
722      * and the decoder should batch the data until a buffer without
723      * this flag appears before decoding the frame.
724      *
725      * @see MediaCodec#BUFFER_FLAG_PARTIAL_FRAME
726      */
727     public static final int SAMPLE_FLAG_PARTIAL_FRAME = 4;
728 
729     /** @hide */
730     @IntDef(
731         flag = true,
732         value = {
733             SAMPLE_FLAG_SYNC,
734             SAMPLE_FLAG_ENCRYPTED,
735             SAMPLE_FLAG_PARTIAL_FRAME,
736     })
737     @Retention(RetentionPolicy.SOURCE)
738     public @interface SampleFlag {}
739 
740     /**
741      * Returns the current sample's flags.
742      */
743     @SampleFlag
744     public native int getSampleFlags();
745 
746     /**
747      * If the sample flags indicate that the current sample is at least
748      * partially encrypted, this call returns relevant information about
749      * the structure of the sample data required for decryption.
750      * @param info The android.media.MediaCodec.CryptoInfo structure
751      *             to be filled in.
752      * @return true iff the sample flags contain {@link #SAMPLE_FLAG_ENCRYPTED}
753      */
754     public native boolean getSampleCryptoInfo(@NonNull MediaCodec.CryptoInfo info);
755 
756     /**
757      * Returns an estimate of how much data is presently cached in memory
758      * expressed in microseconds. Returns -1 if that information is unavailable
759      * or not applicable (no cache).
760      */
761     public native long getCachedDuration();
762 
763     /**
764      * Returns true iff we are caching data and the cache has reached the
765      * end of the data stream (for now, a future seek may of course restart
766      * the fetching of data).
767      * This API only returns a meaningful result if {@link #getCachedDuration}
768      * indicates the presence of a cache, i.e. does NOT return -1.
769      */
770     public native boolean hasCacheReachedEndOfStream();
771 
772     /**
773      * Sets the {@link LogSessionId} for MediaExtractor.
774      */
775     public void setLogSessionId(@NonNull LogSessionId logSessionId) {
776         mLogSessionId = Objects.requireNonNull(logSessionId);
777         native_setLogSessionId(logSessionId.getStringId());
778     }
779 
780     /**
781      * Returns the {@link LogSessionId} for MediaExtractor.
782      */
783     @NonNull
784     public LogSessionId getLogSessionId() {
785         return mLogSessionId;
786     }
787 
788     /**
789      *  Return Metrics data about the current media container.
790      *
791      * @return a {@link PersistableBundle} containing the set of attributes and values
792      * available for the media container being handled by this instance
793      * of MediaExtractor.
794      * The attributes are descibed in {@link MetricsConstants}.
795      *
796      *  Additional vendor-specific fields may also be present in
797      *  the return value.
798      */
799 
800     public PersistableBundle getMetrics() {
801         PersistableBundle bundle = native_getMetrics();
802         return bundle;
803     }
804 
805     private native void native_setLogSessionId(String logSessionId);
806     private native PersistableBundle native_getMetrics();
807 
808     private static native final void native_init();
809     private native final void native_setup();
810     private native final void native_finalize();
811 
812     static {
813         System.loadLibrary("media_jni");
814         native_init();
815     }
816 
817     private MediaCas mMediaCas;
818     @NonNull private LogSessionId mLogSessionId = LogSessionId.LOG_SESSION_ID_NONE;
819 
820     private long mNativeContext;
821 
822     public final static class MetricsConstants
823     {
824         private MetricsConstants() {}
825 
826         /**
827          * Key to extract the container format
828          * from the {@link MediaExtractor#getMetrics} return value.
829          * The value is a String.
830          */
831         public static final String FORMAT = "android.media.mediaextractor.fmt";
832 
833         /**
834          * Key to extract the container MIME type
835          * from the {@link MediaExtractor#getMetrics} return value.
836          * The value is a String.
837          */
838         public static final String MIME_TYPE = "android.media.mediaextractor.mime";
839 
840         /**
841          * Key to extract the number of tracks in the container
842          * from the {@link MediaExtractor#getMetrics} return value.
843          * The value is an integer.
844          */
845         public static final String TRACKS = "android.media.mediaextractor.ntrk";
846 
847     }
848 
849 }
850