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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 java.nio.ByteBuffer;
     20 import java.util.HashMap;
     21 import java.util.Map;
     22 
     23 /**
     24  * Encapsulates the information describing the format of media data,
     25  * be it audio or video.
     26  *
     27  * The format of the media data is specified as string/value pairs.
     28  *
     29  * Keys common to all audio/video formats, <b>all keys not marked optional are mandatory</b>:
     30  *
     31  * <table>
     32  * <tr><th>Name</th><th>Value Type</th><th>Description</th></tr>
     33  * <tr><td>{@link #KEY_MIME}</td><td>String</td><td>The type of the format.</td></tr>
     34  * <tr><td>{@link #KEY_MAX_INPUT_SIZE}</td><td>Integer</td><td>optional, maximum size of a buffer of input data</td></tr>
     35  * <tr><td>{@link #KEY_BIT_RATE}</td><td>Integer</td><td><b>encoder-only</b>, desired bitrate in bits/second</td></tr>
     36  * </table>
     37  *
     38  * Video formats have the following keys:
     39  * <table>
     40  * <tr><th>Name</th><th>Value Type</th><th>Description</th></tr>
     41  * <tr><td>{@link #KEY_WIDTH}</td><td>Integer</td><td></td></tr>
     42  * <tr><td>{@link #KEY_HEIGHT}</td><td>Integer</td><td></td></tr>
     43  * <tr><td>{@link #KEY_COLOR_FORMAT}</td><td>Integer</td><td>set by the user
     44  *         for encoders, readable in the output format of decoders</b></td></tr>
     45  * <tr><td>{@link #KEY_FRAME_RATE}</td><td>Integer or Float</td><td><b>encoder-only</b></td></tr>
     46  * <tr><td>{@link #KEY_CAPTURE_RATE}</td><td>Integer</td><td></td></tr>
     47 * <tr><td>{@link #KEY_I_FRAME_INTERVAL}</td><td>Integer</td><td><b>encoder-only</b></td></tr>
     48  * <tr><td>{@link #KEY_MAX_WIDTH}</td><td>Integer</td><td><b>decoder-only</b>, optional, max-resolution width</td></tr>
     49  * <tr><td>{@link #KEY_MAX_HEIGHT}</td><td>Integer</td><td><b>decoder-only</b>, optional, max-resolution height</td></tr>
     50  * <tr><td>{@link #KEY_REPEAT_PREVIOUS_FRAME_AFTER}</td><td>Long</td><td><b>video encoder in surface-mode only</b></td></tr>
     51  * <tr><td>{@link #KEY_PUSH_BLANK_BUFFERS_ON_STOP}</td><td>Integer(1)</td><td><b>video decoder rendering to a surface only</b></td></tr>
     52  * </table>
     53  * Specify both {@link #KEY_MAX_WIDTH} and {@link #KEY_MAX_HEIGHT} to enable
     54  * adaptive playback (seamless resolution change) for a video decoder that
     55  * supports it ({@link MediaCodecInfo.CodecCapabilities#FEATURE_AdaptivePlayback}).
     56  * The values are used as hints for the codec: they are the maximum expected
     57  * resolution to prepare for.  Depending on codec support, preparing for larger
     58  * maximum resolution may require more memory even if that resolution is never
     59  * reached.  These fields have no effect for codecs that do not support adaptive
     60  * playback.<br /><br />
     61  *
     62  * Audio formats have the following keys:
     63  * <table>
     64  * <tr><th>Name</th><th>Value Type</th><th>Description</th></tr>
     65  * <tr><td>{@link #KEY_CHANNEL_COUNT}</td><td>Integer</td><td></td></tr>
     66  * <tr><td>{@link #KEY_SAMPLE_RATE}</td><td>Integer</td><td></td></tr>
     67  * <tr><td>{@link #KEY_IS_ADTS}</td><td>Integer</td><td>optional, if <em>decoding</em> AAC audio content, setting this key to 1 indicates that each audio frame is prefixed by the ADTS header.</td></tr>
     68  * <tr><td>{@link #KEY_AAC_PROFILE}</td><td>Integer</td><td><b>encoder-only</b>, optional, if content is AAC audio, specifies the desired profile.</td></tr>
     69  * <tr><td>{@link #KEY_AAC_SBR_MODE}</td><td>Integer</td><td><b>encoder-only</b>, optional, if content is AAC audio, specifies the desired SBR mode.</td></tr>
     70  * <tr><td>{@link #KEY_AAC_DRC_TARGET_REFERENCE_LEVEL}</td><td>Integer</td><td><b>decoder-only</b>, optional, if content is AAC audio, specifies the target reference level.</td></tr>
     71  * <tr><td>{@link #KEY_AAC_ENCODED_TARGET_LEVEL}</td><td>Integer</td><td><b>decoder-only</b>, optional, if content is AAC audio, specifies the target reference level used at encoder.</td></tr>
     72  * <tr><td>{@link #KEY_AAC_DRC_BOOST_FACTOR}</td><td>Integer</td><td><b>decoder-only</b>, optional, if content is AAC audio, specifies the DRC boost factor.</td></tr>
     73  * <tr><td>{@link #KEY_AAC_DRC_ATTENUATION_FACTOR}</td><td>Integer</td><td><b>decoder-only</b>, optional, if content is AAC audio, specifies the DRC attenuation factor.</td></tr>
     74  * <tr><td>{@link #KEY_AAC_DRC_HEAVY_COMPRESSION}</td><td>Integer</td><td><b>decoder-only</b>, optional, if content is AAC audio, specifies whether to use heavy compression.</td></tr>
     75  * <tr><td>{@link #KEY_AAC_MAX_OUTPUT_CHANNEL_COUNT}</td><td>Integer</td><td><b>decoder-only</b>, optional, if content is AAC audio, specifies the maximum number of channels the decoder outputs.</td></tr>
     76  * <tr><td>{@link #KEY_CHANNEL_MASK}</td><td>Integer</td><td>optional, a mask of audio channel assignments</td></tr>
     77  * <tr><td>{@link #KEY_FLAC_COMPRESSION_LEVEL}</td><td>Integer</td><td><b>encoder-only</b>, optional, if content is FLAC audio, specifies the desired compression level.</td></tr>
     78  * </table>
     79  *
     80  * Subtitle formats have the following keys:
     81  * <table>
     82  * <tr><td>{@link #KEY_MIME}</td><td>String</td><td>The type of the format.</td></tr>
     83  * <tr><td>{@link #KEY_LANGUAGE}</td><td>String</td><td>The language of the content.</td></tr>
     84  * </table>
     85  */
     86 public final class MediaFormat {
     87     public static final String MIMETYPE_VIDEO_VP8 = "video/x-vnd.on2.vp8";
     88     public static final String MIMETYPE_VIDEO_VP9 = "video/x-vnd.on2.vp9";
     89     public static final String MIMETYPE_VIDEO_AVC = "video/avc";
     90     public static final String MIMETYPE_VIDEO_HEVC = "video/hevc";
     91     public static final String MIMETYPE_VIDEO_MPEG4 = "video/mp4v-es";
     92     public static final String MIMETYPE_VIDEO_H263 = "video/3gpp";
     93     public static final String MIMETYPE_VIDEO_MPEG2 = "video/mpeg2";
     94     public static final String MIMETYPE_VIDEO_RAW = "video/raw";
     95 
     96     public static final String MIMETYPE_AUDIO_AMR_NB = "audio/3gpp";
     97     public static final String MIMETYPE_AUDIO_AMR_WB = "audio/amr-wb";
     98     public static final String MIMETYPE_AUDIO_MPEG = "audio/mpeg";
     99     public static final String MIMETYPE_AUDIO_AAC = "audio/mp4a-latm";
    100     public static final String MIMETYPE_AUDIO_QCELP = "audio/qcelp";
    101     public static final String MIMETYPE_AUDIO_VORBIS = "audio/vorbis";
    102     public static final String MIMETYPE_AUDIO_OPUS = "audio/opus";
    103     public static final String MIMETYPE_AUDIO_G711_ALAW = "audio/g711-alaw";
    104     public static final String MIMETYPE_AUDIO_G711_MLAW = "audio/g711-mlaw";
    105     public static final String MIMETYPE_AUDIO_RAW = "audio/raw";
    106     public static final String MIMETYPE_AUDIO_FLAC = "audio/flac";
    107     public static final String MIMETYPE_AUDIO_MSGSM = "audio/gsm";
    108     public static final String MIMETYPE_AUDIO_AC3 = "audio/ac3";
    109     public static final String MIMETYPE_AUDIO_EAC3 = "audio/eac3";
    110 
    111     /**
    112      * MIME type for WebVTT subtitle data.
    113      */
    114     public static final String MIMETYPE_TEXT_VTT = "text/vtt";
    115 
    116     /**
    117      * MIME type for CEA-608 closed caption data.
    118      */
    119     public static final String MIMETYPE_TEXT_CEA_608 = "text/cea-608";
    120 
    121     private Map<String, Object> mMap;
    122 
    123     /**
    124      * A key describing the mime type of the MediaFormat.
    125      * The associated value is a string.
    126      */
    127     public static final String KEY_MIME = "mime";
    128 
    129     /**
    130      * A key describing the language of the content, using either ISO 639-1
    131      * or 639-2/T codes.  The associated value is a string.
    132      */
    133     public static final String KEY_LANGUAGE = "language";
    134 
    135     /**
    136      * A key describing the sample rate of an audio format.
    137      * The associated value is an integer
    138      */
    139     public static final String KEY_SAMPLE_RATE = "sample-rate";
    140 
    141     /**
    142      * A key describing the number of channels in an audio format.
    143      * The associated value is an integer
    144      */
    145     public static final String KEY_CHANNEL_COUNT = "channel-count";
    146 
    147     /**
    148      * A key describing the width of the content in a video format.
    149      * The associated value is an integer
    150      */
    151     public static final String KEY_WIDTH = "width";
    152 
    153     /**
    154      * A key describing the height of the content in a video format.
    155      * The associated value is an integer
    156      */
    157     public static final String KEY_HEIGHT = "height";
    158 
    159     /**
    160      * A key describing the maximum expected width of the content in a video
    161      * decoder format, in case there are resolution changes in the video content.
    162      * The associated value is an integer
    163      */
    164     public static final String KEY_MAX_WIDTH = "max-width";
    165 
    166     /**
    167      * A key describing the maximum expected height of the content in a video
    168      * decoder format, in case there are resolution changes in the video content.
    169      * The associated value is an integer
    170      */
    171     public static final String KEY_MAX_HEIGHT = "max-height";
    172 
    173     /** A key describing the maximum size in bytes of a buffer of data
    174      * described by this MediaFormat.
    175      * The associated value is an integer
    176      */
    177     public static final String KEY_MAX_INPUT_SIZE = "max-input-size";
    178 
    179     /**
    180      * A key describing the bitrate in bits/sec.
    181      * The associated value is an integer
    182      */
    183     public static final String KEY_BIT_RATE = "bitrate";
    184 
    185     /**
    186      * A key describing the color format of the content in a video format.
    187      * Constants are declared in {@link android.media.MediaCodecInfo.CodecCapabilities}.
    188      */
    189     public static final String KEY_COLOR_FORMAT = "color-format";
    190 
    191     /**
    192      * A key describing the frame rate of a video format in frames/sec.
    193      * The associated value is an integer or a float.
    194      */
    195     public static final String KEY_FRAME_RATE = "frame-rate";
    196 
    197     /**
    198      * A key describing the capture rate of a video format in frames/sec.
    199      * <p>
    200      * When capture rate is different than the frame rate, it means that the
    201      * video is acquired at a different rate than the playback, which produces
    202      * slow motion or timelapse effect during playback. Application can use the
    203      * value of this key to tell the relative speed ratio between capture and
    204      * playback rates when the video was recorded.
    205      * </p>
    206      * <p>
    207      * The associated value is an integer or a float.
    208      * </p>
    209      */
    210     public static final String KEY_CAPTURE_RATE = "capture-rate";
    211 
    212     /**
    213      * A key describing the frequency of I frames expressed in secs
    214      * between I frames.
    215      * The associated value is an integer.
    216      */
    217     public static final String KEY_I_FRAME_INTERVAL = "i-frame-interval";
    218 
    219     /**
    220      * A key describing the temporal layering schema.  This is an optional parameter
    221      * that applies only to video encoders.  Use {@link MediaCodec#getInputFormat}
    222      * after {@link MediaCodec#configure configure} to query if the encoder supports
    223      * the desired schema. Supported values are {@code webrtc.vp8.1-layer},
    224      * {@code webrtc.vp8.2-layer}, {@code webrtc.vp8.3-layer}, and {@code none}.
    225      * If the encoder does not support temporal layering, the input format will
    226      * not have an entry with this key.
    227      * The associated value is a string.
    228      */
    229     public static final String KEY_TEMPORAL_LAYERING = "ts-schema";
    230 
    231     /**
    232      * A key describing the stride of the video bytebuffer layout.
    233      * Stride (or row increment) is the difference between the index of a pixel
    234      * and that of the pixel directly underneath. For YUV 420 formats, the
    235      * stride corresponds to the Y plane; the stride of the U and V planes can
    236      * be calculated based on the color format.
    237      * The associated value is an integer, representing number of bytes.
    238      */
    239     public static final String KEY_STRIDE = "stride";
    240 
    241     /**
    242      * A key describing the plane height of a multi-planar (YUV) video bytebuffer layout.
    243      * Slice height (or plane height) is the number of rows that must be skipped to get
    244      * from the top of the Y plane to the top of the U plane in the bytebuffer. In essence
    245      * the offset of the U plane is sliceHeight * stride. The height of the U/V planes
    246      * can be calculated based on the color format.
    247      * The associated value is an integer, representing number of rows.
    248      */
    249     public static final String KEY_SLICE_HEIGHT = "slice-height";
    250 
    251     /**
    252      * Applies only when configuring a video encoder in "surface-input" mode.
    253      * The associated value is a long and gives the time in microseconds
    254      * after which the frame previously submitted to the encoder will be
    255      * repeated (once) if no new frame became available since.
    256      */
    257     public static final String KEY_REPEAT_PREVIOUS_FRAME_AFTER
    258         = "repeat-previous-frame-after";
    259 
    260     /**
    261      * If specified when configuring a video decoder rendering to a surface,
    262      * causes the decoder to output "blank", i.e. black frames to the surface
    263      * when stopped to clear out any previously displayed contents.
    264      * The associated value is an integer of value 1.
    265      */
    266     public static final String KEY_PUSH_BLANK_BUFFERS_ON_STOP
    267         = "push-blank-buffers-on-shutdown";
    268 
    269     /**
    270      * A key describing the duration (in microseconds) of the content.
    271      * The associated value is a long.
    272      */
    273     public static final String KEY_DURATION = "durationUs";
    274 
    275     /**
    276      * A key mapping to a value of 1 if the content is AAC audio and
    277      * audio frames are prefixed with an ADTS header.
    278      * The associated value is an integer (0 or 1).
    279      * This key is only supported when _decoding_ content, it cannot
    280      * be used to configure an encoder to emit ADTS output.
    281      */
    282     public static final String KEY_IS_ADTS = "is-adts";
    283 
    284     /**
    285      * A key describing the channel composition of audio content. This mask
    286      * is composed of bits drawn from channel mask definitions in {@link android.media.AudioFormat}.
    287      * The associated value is an integer.
    288      */
    289     public static final String KEY_CHANNEL_MASK = "channel-mask";
    290 
    291     /**
    292      * A key describing the AAC profile to be used (AAC audio formats only).
    293      * Constants are declared in {@link android.media.MediaCodecInfo.CodecProfileLevel}.
    294      */
    295     public static final String KEY_AAC_PROFILE = "aac-profile";
    296 
    297     /**
    298      * A key describing the AAC SBR mode to be used (AAC audio formats only).
    299      * The associated value is an integer and can be set to following values:
    300      * <ul>
    301      * <li>0 - no SBR should be applied</li>
    302      * <li>1 - single rate SBR</li>
    303      * <li>2 - double rate SBR</li>
    304      * </ul>
    305      * Note: If this key is not defined the default SRB mode for the desired AAC profile will
    306      * be used.
    307      * <p>This key is only used during encoding.
    308      */
    309     public static final String KEY_AAC_SBR_MODE = "aac-sbr-mode";
    310 
    311     /**
    312      * A key describing the maximum number of channels that can be output by the AAC decoder.
    313      * By default, the decoder will output the same number of channels as present in the encoded
    314      * stream, if supported. Set this value to limit the number of output channels, and use
    315      * the downmix information in the stream, if available.
    316      * <p>Values larger than the number of channels in the content to decode are ignored.
    317      * <p>This key is only used during decoding.
    318      */
    319     public static final String KEY_AAC_MAX_OUTPUT_CHANNEL_COUNT = "aac-max-output-channel_count";
    320 
    321     /**
    322      * A key describing a gain to be applied so that the output loudness matches the
    323      * Target Reference Level. This is typically used to normalize loudness across program items.
    324      * The gain is derived as the difference between the Target Reference Level and the
    325      * Program Reference Level. The latter can be given in the bitstream and indicates the actual
    326      * loudness value of the program item.
    327      * <p>The value is given as an integer value between
    328      * 0 and 127, and is calculated as -0.25 * Target Reference Level in dBFS.
    329      * Therefore, it represents the range of Full Scale (0 dBFS) to -31.75 dBFS.
    330      * <p>This key is only used during decoding.
    331      */
    332     public static final String KEY_AAC_DRC_TARGET_REFERENCE_LEVEL = "aac-target-ref-level";
    333 
    334     /**
    335      * A key describing the target reference level that was assumed at the encoder for
    336      * calculation of attenuation gains for clipping prevention. This information can be provided
    337      * if it is known, otherwise a worst-case assumption is used.
    338      * <p>The value is given as an integer value between
    339      * 0 and 127, and is calculated as -0.25 * Target Reference Level in dBFS.
    340      * Therefore, it represents the range of Full Scale (0 dBFS) to -31.75 dBFS.
    341      * The default value is the worst-case assumption of 127.
    342      * <p>The value is ignored when heavy compression is used (see
    343      * {@link #KEY_AAC_DRC_HEAVY_COMPRESSION}).
    344      * <p>This key is only used during decoding.
    345      */
    346     public static final String KEY_AAC_ENCODED_TARGET_LEVEL = "aac-encoded-target-level";
    347 
    348     /**
    349      * A key describing the boost factor allowing to adapt the dynamics of the output to the
    350      * actual listening requirements. This relies on DRC gain sequences that can be transmitted in
    351      * the encoded bitstream to be able to reduce the dynamics of the output signal upon request.
    352      * This factor enables the user to select how much of the gains are applied.
    353      * <p>Positive gains (boost) and negative gains (attenuation, see
    354      * {@link #KEY_AAC_DRC_ATTENUATION_FACTOR}) can be controlled separately for a better match
    355      * to different use-cases.
    356      * <p>Typically, attenuation gains are sent for loud signal segments, and boost gains are sent
    357      * for soft signal segments. If the output is listened to in a noisy environment, for example,
    358      * the boost factor is used to enable the positive gains, i.e. to amplify soft signal segments
    359      * beyond the noise floor. But for listening late at night, the attenuation
    360      * factor is used to enable the negative gains, to prevent loud signal from surprising
    361      * the listener. In applications which generally need a low dynamic range, both the boost factor
    362      * and the attenuation factor are used in order to enable all DRC gains.
    363      * <p>In order to prevent clipping, it is also recommended to apply the attenuation factors
    364      * in case of a downmix and/or loudness normalization to high target reference levels.
    365      * <p>Both the boost and the attenuation factor parameters are given as integer values
    366      * between 0 and 127, representing the range of the factor of 0 (i.e. don't apply)
    367      * to 1 (i.e. fully apply boost/attenuation factors respectively).
    368      * <p>This key is only used during decoding.
    369      */
    370     public static final String KEY_AAC_DRC_BOOST_FACTOR = "aac-drc-boost-level";
    371 
    372     /**
    373      * A key describing the attenuation factor allowing to adapt the dynamics of the output to the
    374      * actual listening requirements.
    375      * See {@link #KEY_AAC_DRC_BOOST_FACTOR} for a description of the role of this attenuation
    376      * factor and the value range.
    377      * <p>This key is only used during decoding.
    378      */
    379     public static final String KEY_AAC_DRC_ATTENUATION_FACTOR = "aac-drc-cut-level";
    380 
    381     /**
    382      * A key describing the selection of the heavy compression profile for DRC.
    383      * Two separate DRC gain sequences can be transmitted in one bitstream: MPEG-4 DRC light
    384      * compression, and DVB-specific heavy compression. When selecting the application of the heavy
    385      * compression, one of the sequences is selected:
    386      * <ul>
    387      * <li>0 enables light compression,</li>
    388      * <li>1 enables heavy compression instead.
    389      * </ul>
    390      * Note that only light compression offers the features of scaling of DRC gains
    391      * (see {@link #KEY_AAC_DRC_BOOST_FACTOR} and {@link #KEY_AAC_DRC_ATTENUATION_FACTOR} for the
    392      * boost and attenuation factors, and frequency-selective (multiband) DRC.
    393      * Light compression usually contains clipping prevention for stereo downmixing while heavy
    394      * compression, if additionally provided in the bitstream, is usually stronger, and contains
    395      * clipping prevention for stereo and mono downmixing.
    396      * <p>The default is light compression.
    397      * <p>This key is only used during decoding.
    398      */
    399     public static final String KEY_AAC_DRC_HEAVY_COMPRESSION = "aac-drc-heavy-compression";
    400 
    401     /**
    402      * A key describing the FLAC compression level to be used (FLAC audio format only).
    403      * The associated value is an integer ranging from 0 (fastest, least compression)
    404      * to 8 (slowest, most compression).
    405      */
    406     public static final String KEY_FLAC_COMPRESSION_LEVEL = "flac-compression-level";
    407 
    408     /**
    409      * A key describing the encoding complexity.
    410      * The associated value is an integer.  These values are device and codec specific,
    411      * but lower values generally result in faster and/or less power-hungry encoding.
    412      *
    413      * @see MediaCodecInfo.EncoderCapabilities#getComplexityRange()
    414      */
    415     public static final String KEY_COMPLEXITY = "complexity";
    416 
    417     /**
    418      * A key describing the desired encoding quality.
    419      * The associated value is an integer.  This key is only supported for encoders
    420      * that are configured in constant-quality mode.  These values are device and
    421      * codec specific, but lower values generally result in more efficient
    422      * (smaller-sized) encoding.
    423      *
    424      * @hide
    425      *
    426      * @see MediaCodecInfo.EncoderCapabilities#getQualityRange()
    427      */
    428     public static final String KEY_QUALITY = "quality";
    429 
    430     /**
    431      * A key describing the desired codec priority.
    432      * <p>
    433      * The associated value is an integer. Higher value means lower priority.
    434      * <p>
    435      * Currently, only two levels are supported:<br>
    436      * 0: realtime priority - meaning that the codec shall support the given
    437      *    performance configuration (e.g. framerate) at realtime. This should
    438      *    only be used by media playback, capture, and possibly by realtime
    439      *    communication scenarios if best effort performance is not suitable.<br>
    440      * 1: non-realtime priority (best effort).
    441      * <p>
    442      * This is a hint used at codec configuration and resource planning - to understand
    443      * the realtime requirements of the application; however, due to the nature of
    444      * media components, performance is not guaranteed.
    445      *
    446      */
    447     public static final String KEY_PRIORITY = "priority";
    448 
    449     /**
    450      * A key describing the desired operating frame rate for video or sample rate for audio
    451      * that the codec will need to operate at.
    452      * <p>
    453      * The associated value is an integer or a float representing frames-per-second or
    454      * samples-per-second
    455      * <p>
    456      * This is used for cases like high-speed/slow-motion video capture, where the video encoder
    457      * format contains the target playback rate (e.g. 30fps), but the component must be able to
    458      * handle the high operating capture rate (e.g. 240fps).
    459      * <p>
    460      * This rate will be used by codec for resource planning and setting the operating points.
    461      *
    462      */
    463     public static final String KEY_OPERATING_RATE = "operating-rate";
    464 
    465     /**
    466      * A key describing the desired profile to be used by an encoder.
    467      * The associated value is an integer.
    468      * Constants are declared in {@link MediaCodecInfo.CodecProfileLevel}.
    469      * This key is used as a hint, and is only supported for codecs
    470      * that specify a profile.
    471      *
    472      * @see MediaCodecInfo.CodecCapabilities#profileLevels
    473      */
    474     public static final String KEY_PROFILE = "profile";
    475 
    476     /**
    477      * A key describing the desired profile to be used by an encoder.
    478      * The associated value is an integer.
    479      * Constants are declared in {@link MediaCodecInfo.CodecProfileLevel}.
    480      * This key is used as a further hint when specifying a desired profile,
    481      * and is only supported for codecs that specify a level.
    482      * <p>
    483      * This key is ignored if the {@link #KEY_PROFILE profile} is not specified.
    484      *
    485      * @see MediaCodecInfo.CodecCapabilities#profileLevels
    486      */
    487     public static final String KEY_LEVEL = "level";
    488 
    489     /**
    490      * A key describing the desired clockwise rotation on an output surface.
    491      * This key is only used when the codec is configured using an output surface.
    492      * The associated value is an integer, representing degrees.
    493      *
    494      * @see MediaCodecInfo.CodecCapabilities#profileLevels
    495      */
    496     public static final String KEY_ROTATION = "rotation-degrees";
    497 
    498     /**
    499      * A key describing the desired bitrate mode to be used by an encoder.
    500      * Constants are declared in {@link MediaCodecInfo.CodecCapabilities}.
    501      *
    502      * @see MediaCodecInfo.EncoderCapabilities#isBitrateModeSupported(int)
    503      */
    504     public static final String KEY_BITRATE_MODE = "bitrate-mode";
    505 
    506     /**
    507      * A key describing the audio session ID of the AudioTrack associated
    508      * to a tunneled video codec.
    509      * The associated value is an integer.
    510      *
    511      * @see MediaCodecInfo.CodecCapabilities#FEATURE_TunneledPlayback
    512      */
    513     public static final String KEY_AUDIO_SESSION_ID = "audio-session-id";
    514 
    515     /**
    516      * A key for boolean AUTOSELECT behavior for the track. Tracks with AUTOSELECT=true
    517      * are considered when automatically selecting a track without specific user
    518      * choice, based on the current locale.
    519      * This is currently only used for subtitle tracks, when the user selected
    520      * 'Default' for the captioning locale.
    521      * The associated value is an integer, where non-0 means TRUE.  This is an optional
    522      * field; if not specified, AUTOSELECT defaults to TRUE.
    523      */
    524     public static final String KEY_IS_AUTOSELECT = "is-autoselect";
    525 
    526     /**
    527      * A key for boolean DEFAULT behavior for the track. The track with DEFAULT=true is
    528      * selected in the absence of a specific user choice.
    529      * This is currently only used for subtitle tracks, when the user selected
    530      * 'Default' for the captioning locale.
    531      * The associated value is an integer, where non-0 means TRUE.  This is an optional
    532      * field; if not specified, DEFAULT is considered to be FALSE.
    533      */
    534     public static final String KEY_IS_DEFAULT = "is-default";
    535 
    536 
    537     /**
    538      * A key for the FORCED field for subtitle tracks. True if it is a
    539      * forced subtitle track.  Forced subtitle tracks are essential for the
    540      * content and are shown even when the user turns off Captions.  They
    541      * are used for example to translate foreign/alien dialogs or signs.
    542      * The associated value is an integer, where non-0 means TRUE.  This is an
    543      * optional field; if not specified, FORCED defaults to FALSE.
    544      */
    545     public static final String KEY_IS_FORCED_SUBTITLE = "is-forced-subtitle";
    546 
    547     /** @hide */
    548     public static final String KEY_IS_TIMED_TEXT = "is-timed-text";
    549 
    550     /* package private */ MediaFormat(Map<String, Object> map) {
    551         mMap = map;
    552     }
    553 
    554     /**
    555      * Creates an empty MediaFormat
    556      */
    557     public MediaFormat() {
    558         mMap = new HashMap();
    559     }
    560 
    561     /* package private */ Map<String, Object> getMap() {
    562         return mMap;
    563     }
    564 
    565     /**
    566      * Returns true iff a key of the given name exists in the format.
    567      */
    568     public final boolean containsKey(String name) {
    569         return mMap.containsKey(name);
    570     }
    571 
    572     /**
    573      * A key prefix used together with a {@link MediaCodecInfo.CodecCapabilities}
    574      * feature name describing a required or optional feature for a codec capabilities
    575      * query.
    576      * The associated value is an integer, where non-0 value means the feature is
    577      * requested to be present, while 0 value means the feature is requested to be not
    578      * present.
    579      * @see MediaCodecList#findDecoderForFormat
    580      * @see MediaCodecList#findEncoderForFormat
    581      * @see MediaCodecInfo.CodecCapabilities#isFormatSupported
    582      *
    583      * @hide
    584      */
    585     public static final String KEY_FEATURE_ = "feature-";
    586 
    587     /**
    588      * Returns the value of an integer key.
    589      */
    590     public final int getInteger(String name) {
    591         return ((Integer)mMap.get(name)).intValue();
    592     }
    593 
    594     /**
    595      * Returns the value of an integer key, or the default value if the
    596      * key is missing or is for another type value.
    597      * @hide
    598      */
    599     public final int getInteger(String name, int defaultValue) {
    600         try {
    601             return getInteger(name);
    602         }
    603         catch (NullPointerException  e) { /* no such field */ }
    604         catch (ClassCastException e) { /* field of different type */ }
    605         return defaultValue;
    606     }
    607 
    608     /**
    609      * Returns the value of a long key.
    610      */
    611     public final long getLong(String name) {
    612         return ((Long)mMap.get(name)).longValue();
    613     }
    614 
    615     /**
    616      * Returns the value of a float key.
    617      */
    618     public final float getFloat(String name) {
    619         return ((Float)mMap.get(name)).floatValue();
    620     }
    621 
    622     /**
    623      * Returns the value of a string key.
    624      */
    625     public final String getString(String name) {
    626         return (String)mMap.get(name);
    627     }
    628 
    629     /**
    630      * Returns the value of a ByteBuffer key.
    631      */
    632     public final ByteBuffer getByteBuffer(String name) {
    633         return (ByteBuffer)mMap.get(name);
    634     }
    635 
    636     /**
    637      * Returns whether a feature is to be enabled ({@code true}) or disabled
    638      * ({@code false}).
    639      *
    640      * @param feature the name of a {@link MediaCodecInfo.CodecCapabilities} feature.
    641      *
    642      * @throws IllegalArgumentException if the feature was neither set to be enabled
    643      *        nor to be disabled.
    644      */
    645     public boolean getFeatureEnabled(String feature) {
    646         Integer enabled = (Integer)mMap.get(KEY_FEATURE_ + feature);
    647         if (enabled == null) {
    648             throw new IllegalArgumentException("feature is not specified");
    649         }
    650         return enabled != 0;
    651     }
    652 
    653     /**
    654      * Sets the value of an integer key.
    655      */
    656     public final void setInteger(String name, int value) {
    657         mMap.put(name, Integer.valueOf(value));
    658     }
    659 
    660     /**
    661      * Sets the value of a long key.
    662      */
    663     public final void setLong(String name, long value) {
    664         mMap.put(name, Long.valueOf(value));
    665     }
    666 
    667     /**
    668      * Sets the value of a float key.
    669      */
    670     public final void setFloat(String name, float value) {
    671         mMap.put(name, new Float(value));
    672     }
    673 
    674     /**
    675      * Sets the value of a string key.
    676      */
    677     public final void setString(String name, String value) {
    678         mMap.put(name, value);
    679     }
    680 
    681     /**
    682      * Sets the value of a ByteBuffer key.
    683      */
    684     public final void setByteBuffer(String name, ByteBuffer bytes) {
    685         mMap.put(name, bytes);
    686     }
    687 
    688     /**
    689      * Sets whether a feature is to be enabled ({@code true}) or disabled
    690      * ({@code false}).
    691      *
    692      * If {@code enabled} is {@code true}, the feature is requested to be present.
    693      * Otherwise, the feature is requested to be not present.
    694      *
    695      * @param feature the name of a {@link MediaCodecInfo.CodecCapabilities} feature.
    696      *
    697      * @see MediaCodecList#findDecoderForFormat
    698      * @see MediaCodecList#findEncoderForFormat
    699      * @see MediaCodecInfo.CodecCapabilities#isFormatSupported
    700      */
    701     public void setFeatureEnabled(String feature, boolean enabled) {
    702         setInteger(KEY_FEATURE_ + feature, enabled ? 1 : 0);
    703     }
    704 
    705     /**
    706      * Creates a minimal audio format.
    707      * @param mime The mime type of the content.
    708      * @param sampleRate The sampling rate of the content.
    709      * @param channelCount The number of audio channels in the content.
    710      */
    711     public static final MediaFormat createAudioFormat(
    712             String mime,
    713             int sampleRate,
    714             int channelCount) {
    715         MediaFormat format = new MediaFormat();
    716         format.setString(KEY_MIME, mime);
    717         format.setInteger(KEY_SAMPLE_RATE, sampleRate);
    718         format.setInteger(KEY_CHANNEL_COUNT, channelCount);
    719 
    720         return format;
    721     }
    722 
    723     /**
    724      * Creates a minimal subtitle format.
    725      * @param mime The mime type of the content.
    726      * @param language The language of the content, using either ISO 639-1 or 639-2/T
    727      *        codes.  Specify null or "und" if language information is only included
    728      *        in the content.  (This will also work if there are multiple language
    729      *        tracks in the content.)
    730      */
    731     public static final MediaFormat createSubtitleFormat(
    732             String mime,
    733             String language) {
    734         MediaFormat format = new MediaFormat();
    735         format.setString(KEY_MIME, mime);
    736         format.setString(KEY_LANGUAGE, language);
    737 
    738         return format;
    739     }
    740 
    741     /**
    742      * Creates a minimal video format.
    743      * @param mime The mime type of the content.
    744      * @param width The width of the content (in pixels)
    745      * @param height The height of the content (in pixels)
    746      */
    747     public static final MediaFormat createVideoFormat(
    748             String mime,
    749             int width,
    750             int height) {
    751         MediaFormat format = new MediaFormat();
    752         format.setString(KEY_MIME, mime);
    753         format.setInteger(KEY_WIDTH, width);
    754         format.setInteger(KEY_HEIGHT, height);
    755 
    756         return format;
    757     }
    758 
    759     @Override
    760     public String toString() {
    761         return mMap.toString();
    762     }
    763 }
    764