5.2. Video Encoding

If device implementations support any video encoder and make it available to third-party apps, they:

  • SHOULD NOT be, over two sliding windows, more than ~15% over the bitrate between intraframe (I-frame) intervals.
  • SHOULD NOT be more than ~100% over the bitrate over a sliding window of 1 second.

If device implementations include an embedded screen display with the diagonal length of at least 2.5 inches or include a video output port or declare the support of a camera via the android.hardware.camera.any feature flag, they:

  • [C-1-1] MUST include the support of at least one of the VP8 or H.264 video encoders, and make it available for third-party applications.
  • SHOULD support both VP8 and H.264 video encoders, and make it available for third-party applications.

If device implementations support any of the H.264, VP8, VP9 or HEVC video encoders and make it available to third-party applications, they:

  • [C-2-1] MUST support dynamically configurable bitrates.
  • SHOULD support variable frame rates, where video encoder SHOULD determine instantaneous frame duration based on the timestamps of input buffers, and allocate its bit bucket based on that frame duration.

If device implementations support the MPEG-4 SP video encoder and make it available to third-party apps, they:

  • SHOULD support dynamically configurable bitrates for the supported encoder.

5.2.1. H.263

If device implementations support H.263 encoders and make it available to third-party apps, they:

  • [C-1-1] MUST support Baseline Profile Level 45.
  • SHOULD support dynamically configurable bitrates for the supported encoder.

5.2.2. H-264

If device implementations support H.264 codec, they:

  • [C-1-1] MUST support Baseline Profile Level 3. However, support for ASO (Arbitrary Slice Ordering), FMO (Flexible Macroblock Ordering) and RS (Redundant Slices) is OPTIONAL. Moreover, to maintain compatibility with other Android devices, it is RECOMMENDED that ASO, FMO and RS are not used for Baseline Profile by encoders.
  • [C-1-2] MUST support the SD (Standard Definition) video encoding profiles in the following table.
  • SHOULD support Main Profile Level 4.
  • SHOULD support the HD (High Definition) video encoding profiles as indicated in the following table.

If device implementations report support of H.264 encoding for 720p or 1080p resolution videos through the media APIs, they:

  • [C-2-1] MUST support the encoding profiles in the following table.

5.2.3. VP8

If device implementations support VP8 codec, they:

  • [C-1-1] MUST support the SD video encoding profiles.
  • SHOULD support the following HD (High Definition) video encoding profiles.
  • SHOULD support writing Matroska WebM files.
  • SHOULD use a hardware VP8 codec that meets the WebM project RTC hardware coding requirements, to ensure acceptable quality of web video streaming and video-conference services.

If device implementations report support of VP8 encoding for 720p or 1080p resolution videos through the media APIs, they:

  • [C-2-1] MUST support the encoding profiles in the following table.

5.2.4. VP9

If device implementations support VP9 codec, they:

  • SHOULD support writing Matroska WebM files.