Provides media definitions that are common between the Decoder and Player interfaces. ## Macros ### kSbMediaBitsPerPixelInvalid Value used when a video's bits per pixel is not known. ### kSbMediaVideoResolutionDimensionInvalid Value used when a video's resolution is not known. ## Enums ### SbMediaAudioCodec Types of audio elementary streams that can be supported. #### Values - `kSbMediaAudioCodecNone` - `kSbMediaAudioCodecAac` - `kSbMediaAudioCodecAc3` - `kSbMediaAudioCodecEac3` - `kSbMediaAudioCodecOpus` - `kSbMediaAudioCodecVorbis` - `kSbMediaAudioCodecMp3` - `kSbMediaAudioCodecFlac` - `kSbMediaAudioCodecPcm` ### SbMediaAudioCodingType Possible audio coding types. #### Values - `kSbMediaAudioCodingTypeNone` - `kSbMediaAudioCodingTypeAac` - `kSbMediaAudioCodingTypeAc3` - `kSbMediaAudioCodingTypeAtrac` - `kSbMediaAudioCodingTypeBitstream` - `kSbMediaAudioCodingTypeDolbyDigitalPlus` - `kSbMediaAudioCodingTypeDts` - `kSbMediaAudioCodingTypeMpeg1` - `kSbMediaAudioCodingTypeMpeg2` - `kSbMediaAudioCodingTypeMpeg3` - `kSbMediaAudioCodingTypePcm` ### SbMediaAudioConnector Possible audio connector types. #### Values - `kSbMediaAudioConnectorNone` - `kSbMediaAudioConnectorAnalog` - `kSbMediaAudioConnectorBluetooth` - `kSbMediaAudioConnectorHdmi` - `kSbMediaAudioConnectorNetwork` - `kSbMediaAudioConnectorSpdif` - `kSbMediaAudioConnectorUsb` ### SbMediaAudioFrameStorageType Possible audio frame storage types. #### Values - `kSbMediaAudioFrameStorageTypeInterleaved` The samples of a multi-channel audio stream are stored in one continuous buffer. Samples at the same timestamp are stored one after another. For example, for a stereo stream with channels L and R that contains samples with timestamps 0, 1, 2, etc., the samples are stored in one buffer as "L0 R0 L1 R1 L2 R2 ...". - `kSbMediaAudioFrameStorageTypePlanar` The samples of each channel are stored in their own continuous buffer. For example, for a stereo stream with channels L and R that contains samples with timestamps 0, 1, 2, etc., the samples are stored in two buffers "L0 L1 L2 ..." and "R0 R1 R2 ...". ### SbMediaAudioSampleType Possible audio sample types. #### Values - `kSbMediaAudioSampleTypeInt16Deprecated` - `kSbMediaAudioSampleTypeFloat32` ### SbMediaRangeId This corresponds to the WebM Range enum which is part of WebM color data (see ). H.264 only uses a bool, which corresponds to the LIMITED/FULL values. Chrome- specific values start at 1000. #### Values - `kSbMediaRangeIdUnspecified` Range is not explicitly specified / unknown. - `kSbMediaRangeIdLimited` Limited Rec. 709 color range with RGB values ranging from 16 to 235. - `kSbMediaRangeIdFull` Full RGB color range with RGB values from 0 to 255. - `kSbMediaRangeIdDerived` Range is defined by TransferId/MatrixId. - `kSbMediaRangeIdLast` ### SbMediaSupportType Indicates how confident the device is that it can play media resources of the given type. The values are a direct map of the canPlayType() method specified at the following link: #### Values - `kSbMediaSupportTypeNotSupported` The media type cannot be played. - `kSbMediaSupportTypeMaybe` Cannot determine if the media type is playable without playing it. - `kSbMediaSupportTypeProbably` The media type seems to be playable. ### SbMediaType Types of media component streams. #### Values - `kSbMediaTypeAudio` Value used for audio streams. - `kSbMediaTypeVideo` Value used for video streams. ### SbMediaVideoCodec Types of video elementary streams that could be supported. #### Values - `kSbMediaVideoCodecNone` - `kSbMediaVideoCodecH264` - `kSbMediaVideoCodecH265` - `kSbMediaVideoCodecMpeg2` - `kSbMediaVideoCodecTheora` - `kSbMediaVideoCodecVc1` - `kSbMediaVideoCodecAv1` - `kSbMediaVideoCodecVp8` - `kSbMediaVideoCodecVp9` ## Structs ### SbMediaAudioConfiguration A structure describing the audio configuration parameters of a single audio output. #### Members - `int index` The platform-defined index of the associated audio output. - `SbMediaAudioConnector connector` The type of audio connector. Will be the empty `kSbMediaAudioConnectorNone` if this device cannot provide this information. - `int64_t latency` The expected latency of audio over this output, in microseconds, or `0` if this device cannot provide this information. - `SbMediaAudioCodingType coding_type` The type of audio coding used over this connection. - `int number_of_channels` The number of audio channels currently supported by this device output, or `0` if this device cannot provide this information, in which case the caller can probably assume stereo output. ### SbMediaAudioSampleInfo An audio sample info, which is a description of a given audio sample. This acts as a set of instructions to the audio decoder. The audio sample info consists of information found in the `WAVEFORMATEX` structure, as well as other information for the audio decoder, including the Audio-specific configuration field. The `WAVEFORMATEX` structure is specified at . #### Members - `SbMediaAudioCodec codec` The audio codec of this sample. - `const char * mime` The mime of the audio stream when `codec` isn't kSbMediaAudioCodecNone. It may point to an empty string if the mime is not available, and it can only be set to NULL when `codec` is kSbMediaAudioCodecNone. - `uint16_t format_tag` The waveform-audio format type code. - `uint16_t number_of_channels` The number of audio channels in this format. `1` for mono, `2` for stereo. - `uint32_t samples_per_second` The sampling rate. - `uint32_t average_bytes_per_second` The number of bytes per second expected with this format. - `uint16_t block_alignment` Byte block alignment, e.g., 4. - `uint16_t bits_per_sample` The bit depth for the stream this represents, e.g. `8` or `16`. - `uint16_t audio_specific_config_size` The size, in bytes, of the audio_specific_config. - `const void * audio_specific_config` The AudioSpecificConfig, as specified in ISO/IEC-14496-3, section 1.6.2.1. ### SbMediaColorMetadata HDR (High Dynamic Range) Metadata common for HDR10 and WebM/VP9-based HDR formats, together with the ColorSpace. HDR reproduces a greater dynamic range of luminosity than is possible with standard digital imaging. #### Members - `unsigned int bits_per_channel` Number of decoded bits per channel. A value of 0 indicates that the BitsPerChannel is unspecified. - `unsigned int chroma_subsampling_horizontal` The amount of pixels to remove in the Cr and Cb channels for every pixel not removed horizontally. Example: For video with 4:2:0 chroma subsampling, the `chroma_subsampling_horizontal` should be set to 1. - `unsigned int chroma_subsampling_vertical` The amount of pixels to remove in the Cr and Cb channels for every pixel not removed vertically. Example: For video with 4:2:0 chroma subsampling, the `chroma_subsampling_vertical` should be set to 1. - `unsigned int cb_subsampling_horizontal` The amount of pixels to remove in the Cb channel for every pixel not removed horizontally. This is additive with ChromaSubsamplingHorz. Example: For video with 4:2:1 chroma subsampling, the `chroma_subsampling_horizontal` should be set to 1 and `cb_subsampling_horizontal` should be set to 1. - `unsigned int cb_subsampling_vertical` The amount of pixels to remove in the Cb channel for every pixel not removed vertically. This is additive with `chroma_subsampling_vertical`. - `unsigned int chroma_siting_horizontal` How chroma is subsampled horizontally. (0: Unspecified, 1: Left Collocated, 2: Half). - `unsigned int chroma_siting_vertical` How chroma is subsampled vertically. (0: Unspecified, 1: Top Collocated, 2: Half). - `SbMediaMasteringMetadata mastering_metadata` \[HDR Metadata field\] SMPTE 2086 mastering data. - `unsigned int max_cll` \[HDR Metadata field\] Maximum brightness of a single pixel (Maximum Content Light Level) in candelas per square meter (cd/m\^2). - `unsigned int max_fall` \[HDR Metadata field\] Maximum brightness of a single full frame (Maximum Frame-Average Light Level) in candelas per square meter (cd/m\^2). - `SbMediaPrimaryId primaries` \[Color Space field\] The colour primaries of the video. For clarity, the value and meanings for Primaries are adopted from Table 2 of ISO/IEC 23001-8:2013/DCOR1. (0: Reserved, 1: ITU-R BT.709, 2: Unspecified, 3: Reserved, 4: ITU-R BT.470M, 5: ITU-R BT.470BG, 6: SMPTE 170M, 7: SMPTE 240M, 8: FILM, 9: ITU-R BT.2020, 10: SMPTE ST 428-1, 22: JEDEC P22 phosphors). - `SbMediaTransferId transfer` \[Color Space field\] The transfer characteristics of the video. For clarity, the value and meanings for TransferCharacteristics 1-15 are adopted from Table 3 of ISO/IEC 23001-8:2013/DCOR1. TransferCharacteristics 16-18 are proposed values. (0: Reserved, 1: ITU-R BT.709, 2: Unspecified, 3: Reserved, 4: Gamma 2.2 curve, 5: Gamma 2.8 curve, 6: SMPTE 170M, 7: SMPTE 240M, 8: Linear, 9: Log, 10: Log Sqrt, 11: IEC 61966-2-4, 12: ITU-R BT.1361 Extended Colour Gamut, 13: IEC 61966-2-1, 14: ITU-R BT.2020 10 bit, 15: ITU-R BT.2020 12 bit, 16: SMPTE ST 2084, 17: SMPTE ST 428-1 18: ARIB STD-B67 (HLG)). - `SbMediaMatrixId matrix` \[Color Space field\] The Matrix Coefficients of the video used to derive luma and chroma values from red, green, and blue color primaries. For clarity, the value and meanings for MatrixCoefficients are adopted from Table 4 of ISO/IEC 23001-8:2013/DCOR1. (0:GBR, 1: BT709, 2: Unspecified, 3: Reserved, 4: FCC, 5: BT470BG, 6: SMPTE 170M, 7: SMPTE 240M, 8: YCOCG, 9: BT2020 Non- constant Luminance, 10: BT2020 Constant Luminance). - `SbMediaRangeId range` \[Color Space field\] Clipping of the color ranges. (0: Unspecified, 1: Broadcast Range, 2: Full range (no clipping), 3: Defined by MatrixCoefficients/TransferCharacteristics). - `float custom_primary_matrix` \[Color Space field\] Only used if primaries == kSbMediaPrimaryIdCustom. This a row-major ordered 3 x 4 submatrix of the 4 x 4 transform matrix. The 4th row is completed as (0, 0, 0, 1). ### SbMediaMasteringMetadata SMPTE 2086 mastering data This standard specifies the metadata items to specify the color volume (the color primaries, white point, and luminance range) of the display that was used in mastering video content. The metadata is specified as a set of values independent of any specific digital representation. Also see the WebM container guidelines: #### Members - `float primary_r_chromaticity_x` Red X chromaticity coordinate as defined by CIE 1931. In range \[0, 1\]. - `float primary_r_chromaticity_y` Red Y chromaticity coordinate as defined by CIE 1931. In range \[0, 1\]. - `float primary_g_chromaticity_x` Green X chromaticity coordinate as defined by CIE 1931. In range \[0, 1\]. - `float primary_g_chromaticity_y` Green Y chromaticity coordinate as defined by CIE 1931. In range \[0, 1\]. - `float primary_b_chromaticity_x` Blue X chromaticity coordinate as defined by CIE 1931. In range \[0, 1\]. - `float primary_b_chromaticity_y` Blue Y chromaticity coordinate as defined by CIE 1931. In range \[0, 1\]. - `float white_point_chromaticity_x` White X chromaticity coordinate as defined by CIE 1931. In range \[0, 1\]. - `float white_point_chromaticity_y` White Y chromaticity coordinate as defined by CIE 1931. In range \[0, 1\]. - `float luminance_max` Maximum luminance. Shall be represented in candelas per square meter (cd/m\^2). In range \[0, 9999.99\]. - `float luminance_min` Minimum luminance. Shall be represented in candelas per square meter (cd/m\^2). In range \[0, 9999.99\]. ### SbMediaVideoSampleInfo The set of information required by the decoder or player for each video sample. #### Members - `SbMediaVideoCodec codec` The video codec of this sample. - `const char * mime` The mime of the video stream when `codec` isn't kSbMediaVideoCodecNone. It may point to an empty string if the mime is not available, and it can only be set to NULL when `codec` is kSbMediaVideoCodecNone. - `const char * max_video_capabilities` Indicates the max video capabilities required. The web app will not provide a video stream exceeding the maximums described by this parameter. Allows the platform to optimize playback pipeline for low quality video streams if it knows that it will never adapt to higher quality streams. The string uses the same format as the string passed in to SbMediaCanPlayMimeAndKeySystem(), for example, when it is set to "width=1920; height=1080; framerate=15;", the video will never adapt to resolution higher than 1920x1080 or frame per second higher than 15 fps. When the maximums are unknown, this will be set to an empty string. It can only be set to NULL when `codec` is kSbMediaVideoCodecNone. - `bool is_key_frame` Indicates whether the associated sample is a key frame (I-frame). Video key frames must always start with SPS and PPS NAL units. - `int frame_width` The frame width of this sample, in pixels. Also could be parsed from the Sequence Parameter Set (SPS) NAL Unit. Frame dimensions must only change on key frames, but may change on any key frame. - `int frame_height` The frame height of this sample, in pixels. Also could be parsed from the Sequence Parameter Set (SPS) NAL Unit. Frame dimensions must only change on key frames, but may change on any key frame. - `SbMediaColorMetadata color_metadata` HDR metadata common for HDR10 and WebM/VP9-based HDR formats as well as the Color Space, and Color elements: MatrixCoefficients, BitsPerChannel, ChromaSubsamplingHorz, ChromaSubsamplingVert, CbSubsamplingHorz, CbSubsamplingVert, ChromaSitingHorz, ChromaSitingVert, Range, TransferCharacteristics, and Primaries described here: . This will only be specified on frames where the HDR metadata and color / color space might have changed (e.g. keyframes). ## Functions ### SbMediaCanPlayMimeAndKeySystem Returns information about whether the playback of the specific media described by `mime` and encrypted using `key_system` can be played. Note that neither `mime` nor `key_system` can be NULL. This function returns `kSbMediaSupportNotSupported` if either is NULL. `mime`: The mime information of the media in the form of `video/webm` or `video/mp4; codecs="avc1.42001E"`. It may include arbitrary parameters like "codecs", "channels", etc. Note that the "codecs" parameter may contain more than one codec, delimited by comma. `key_system`: A lowercase value in the form of "com.example.somesystem", and can be matched exactly with known DRM key systems of the platform. When `key_system` is an empty string, the return value is an indication for non-encrypted media. For more detail, refer to An implementation may choose to support `key_system` with extra attributes, separated by ';', like `com.example.somesystem; attribute_name1="value1"; attribute_name2=value1`. If `key_system` with attributes is not supported by an implementation, it should treat `key_system` as if it contains only the key system, and reject any input containing extra attributes, i.e. it can keep using its existing implementation. When an implementation supports `key_system` with attributes, it has to support all attributes defined by the Starboard version the implementation uses. An implementation should ignore any unknown attributes, and make a decision solely based on the key system and the known attributes. For example, if an implementation supports "com.widevine.alpha", it should also return `kSbMediaSupportTypeProbably` when `key_system` is `com.widevine.alpha; invalid_attribute="invalid_value"`. Currently the only attribute has to be supported is `encryptionscheme`. It reflects the value passed to `encryptionScheme` of MediaKeySystemMediaCapability. It can take value "cenc", "cbcs", or "cbcs-1-9". Empty string is not a valid value for `encryptionscheme` and the implementation should return `kSbMediaSupportTypeNotSupported` when `encryptionscheme` is set to "". The implementation should return `kSbMediaSupportTypeNotSupported` for unknown values of known attributes. For example, if an implementation supports "encryptionscheme" with value "cenc", "cbcs", or "cbcs-1-9", then it should return `kSbMediaSupportTypeProbably` when `key_system` is `com.widevine.alpha; encryptionscheme="cenc"`, and return `kSbMediaSupportTypeNotSupported` when `key_system` is `com.widevine.alpha; encryptionscheme="invalid"`. If an implementation supports key system with attributes on one key system, it has to support key system with attributes on all key systems supported. For more detail, refer to #### Declaration SbMediaSupportType SbMediaCanPlayMimeAndKeySystem(const char *mime, const char *key_system) ### SbMediaGetAudioBufferBudget Specifies the maximum amount of memory used by audio buffers of media source before triggering a garbage collection. A large value will cause more memory being used by audio buffers but will also make the app less likely to re- download audio data. Note that the app may experience significant difficulty if this value is too low. #### Declaration int SbMediaGetAudioBufferBudget() ### SbMediaGetAudioConfiguration Retrieves the current physical audio configuration of audio output `output_index` on this device and places it in `out_configuration`, which must not be NULL. This function returns `false` if nothing could be determined on this platform or if `output_index` does not exist on this device. `out_configuration`: The variable that holds the audio configuration information. #### Declaration bool SbMediaGetAudioConfiguration(int output_index, SbMediaAudioConfiguration *out_configuration) ### SbMediaGetAudioOutputCount Returns the number of audio outputs currently available on this device. Even if the number of outputs or their audio configurations can't be determined, it is expected that the platform will at least return a single output that supports at least stereo. #### Declaration int SbMediaGetAudioOutputCount() ### SbMediaGetBufferAlignment DEPRECATED with SB_API_VERSION 16 SbMediaGetBufferAlignment() was deprecated in Starboard 16, its return value is no longer used when allocating media buffers. This is verified explicitly in nplb tests by ensuring its return value is sizeof(void\*). The app MAY take best effort to allocate media buffers aligned to an optimal alignment for the platform, but not guaranteed. An implementation that has specific alignment requirement should check the alignment of the incoming buffer, and make a copy when necessary. The media buffer will be allocated using the returned alignment. Set this to a larger value may increase the memory consumption of media buffers. #### Declaration int SbMediaGetBufferAlignment() ### SbMediaGetBufferAllocationUnit When the media stack needs more memory to store media buffers, it will allocate extra memory in units returned by SbMediaGetBufferAllocationUnit. This can return 0, in which case the media stack will allocate extra memory on demand. When SbMediaGetInitialBufferCapacity and this function both return 0, the media stack will allocate individual buffers directly using malloc functions. #### Declaration int SbMediaGetBufferAllocationUnit() ### SbMediaGetBufferGarbageCollectionDurationThreshold Specifies the duration threshold of media source garbage collection in microseconds. When the accumulated duration in a source buffer exceeds this value, the media source implementation will try to eject existing buffers from the cache. This is usually triggered when the video being played has a simple content and the encoded data is small. In such case this can limit how much is allocated for the book keeping data of the media buffers and avoid OOM of system heap. This should return 170 seconds for most of the platforms. But it can be further reduced on systems with extremely low memory. #### Declaration int64_t SbMediaGetBufferGarbageCollectionDurationThreshold() ### SbMediaGetBufferPadding DEPRECATED with SB_API_VERSION 16 SbMediaGetBufferPadding() was deprecated in Starboard 16, its return value is no longer used when allocating media buffers. This is verified explicitly in nplb tests by ensuring its return value is 0. An implementation that has specific padding requirement should make a copy of the incoming buffer when necessary. Extra bytes allocated at the end of a media buffer to ensure that the buffer can be use optimally by specific instructions like SIMD. Set to 0 to remove any padding. #### Declaration int SbMediaGetBufferPadding() ### SbMediaGetBufferStorageType Returns SbMediaBufferStorageType of type `SbMediaStorageTypeMemory` or `SbMediaStorageTypeFile`. For memory storage, the media buffers will be stored in main memory allocated by malloc functions. For file storage, the media buffers will be stored in a temporary file in the system cache folder acquired by calling SbSystemGetPath() with "kSbSystemPathCacheDirectory". Note that when its value is "file" the media stack will still allocate memory to cache the buffers in use. #### Declaration SbMediaBufferStorageType SbMediaGetBufferStorageType() ### SbMediaGetInitialBufferCapacity The amount of memory that will be used to store media buffers allocated during system startup. To allocate a large chunk at startup helps with reducing fragmentation and can avoid failures to allocate incrementally. This can return 0. #### Declaration int SbMediaGetInitialBufferCapacity() ### SbMediaGetMaxBufferCapacity The maximum amount of memory that will be used to store media buffers. This must be larger than sum of the video budget and audio budget. This is a soft limit and the app will continue to allocate media buffers even if the accumulated memory used by the media buffers exceeds the maximum buffer capacity. The allocation of media buffers may only fail when there is not enough memory in the system to fulfill the request, under which case the app will be terminated as under other OOM situations. `codec`: the video codec associated with the buffer. `resolution_width`: the width of the video resolution. `resolution_height`: the height of the video resolution. `bits_per_pixel`: the bits per pixel. This value is larger for HDR than non-HDR video. #### Declaration int SbMediaGetMaxBufferCapacity(SbMediaVideoCodec codec, int resolution_width, int resolution_height, int bits_per_pixel) ### SbMediaGetProgressiveBufferBudget The memory used when playing mp4 videos that is not in DASH format. The resolution of such videos shouldn't go beyond 1080p. Its value should be less than the sum of SbMediaGetAudioBufferBudget and 'SbMediaGetVideoBufferBudget(..., 1920, 1080, ...) but not less than 8 MB. `codec`: the video codec associated with the buffer. `resolution_width`: the width of the video resolution. `resolution_height`: the height of the video resolution. `bits_per_pixel`: the bits per pixel. This value is larger for HDR than non-HDR video. #### Declaration int SbMediaGetProgressiveBufferBudget(SbMediaVideoCodec codec, int resolution_width, int resolution_height, int bits_per_pixel) ### SbMediaGetVideoBufferBudget Specifies the maximum amount of memory used by video buffers of media source before triggering a garbage collection. A large value will cause more memory being used by video buffers but will also make app less likely to re-download video data. Note that the app may experience significant difficulty if this value is too low. `codec`: the video codec associated with the buffer. `resolution_width`: the width of the video resolution. `resolution_height`: the height of the video resolution. `bits_per_pixel`: the bits per pixel. This value is larger for HDR than non-HDR video. #### Declaration int SbMediaGetVideoBufferBudget(SbMediaVideoCodec codec, int resolution_width, int resolution_height, int bits_per_pixel) ### SbMediaIsBufferPoolAllocateOnDemand When either SbMediaGetInitialBufferCapacity or SbMediaGetBufferAllocationUnit isn't zero, media buffers will be allocated using a memory pool. Set the following variable to true to allocate the media buffer pool memory on demand and return all memory to the system when there is no media buffer allocated. Setting the following value to false results in that Cobalt will allocate SbMediaGetInitialBufferCapacity bytes for media buffer on startup and will not release any media buffer memory back to the system even if there is no media buffers allocated. This is demonstrated to significantly reduce long-term memory fragmentation. #### Declaration bool SbMediaIsBufferPoolAllocateOnDemand() ### SbMediaIsBufferUsingMemoryPool DEPRECATED with SB_API_VERSION 16 This function is deprecated in Starboard 16 and no longer used. It's not fully removed, only to emit warnings at build and test time. #### Declaration bool SbMediaIsBufferUsingMemoryPool() ### SbMediaSetAudioWriteDuration Communicate to the platform how far past `current_playback_position` the app will write audio samples. The app will write all samples between `current_playback_position` and `current_playback_position` + `duration`, as soon as they are available (during is in microseconds). The app may sometimes write more samples than that, but the app only guarantees to write `duration` past `current_playback_position` in general. The platform is responsible for guaranteeing that when only `duration` audio samples are written at a time, no playback issues occur (such as transient or indefinite hanging). The platform may assume `duration` \>= 0.5 seconds. #### Declaration void SbMediaSetAudioWriteDuration(int64_t duration)