Device implementations:
SHOULD aim for minimum codec latency, in other words, they:
SHOULD NOT consume and store input buffers and return input buffers only
once processed.
SHOULD NOT hold onto decoded buffers for longer than as specified by the
standard (e.g. SPS).
SHOULD NOT hold onto encoded buffers longer than required by the GOP
structure.
All of the codecs listed in the section below are provided as software implementations in the
preferred Android implementation from the Android Open Source Project.
Please note that neither Google nor the Open Handset Alliance make any representation that these
codecs are free from third-party patents. Those intending to use this source code in hardware or
software products are advised that implementations of this code, including in open source software
or shareware, may require patent licenses from the relevant patent holders.
5.1. Media Codecs
5.1.1. Audio Encoding
See more details in
5.1.3. Audio Codecs Details
.
If device implementations declare
android.hardware.microphone
, they MUST support the following audio
encoding:
[C-1-1] PCM/WAVE
5.1.2. Audio Decoding
See more details in
5.1.3. Audio Codecs Details
.
If device implementations declare support for the
android.hardware.audio.output
feature, they must
support decoding the following audio formats:
[C-1-1] MPEG-4 AAC Profile (AAC LC)
[C-1-2] MPEG-4 HE AAC Profile (AAC+)
[C-1-3] MPEG-4 HE AACv2 Profile (enhanced AAC+)
[C-1-4] AAC ELD (enhanced low delay AAC)
[C-1-11] xHE-AAC (ISO/IEC 23003-3 Extended HE AAC Profile, which includes the USAC
Baseline Profile, and ISO/IEC 23003-4 Dynamic Range Control Profile)
[C-1-5] FLAC
[C-1-6] MP3
[C-1-7] MIDI
[C-1-8] Vorbis
[C-1-9] PCM/WAVE
[C-1-10] Opus
If device implementations support the decoding of AAC input buffers of multichannel streams (i.e.
more than two channels) to PCM through the default AAC audio decoder in the
android.media.MediaCodec
API, the following MUST be supported:
[C-2-1] Decoding MUST be performed without downmixing (e.g. a 5.0 AAC stream must be
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