* streamType: Select the type of audio stream this track is attached to
* (e.g. AUDIO_STREAM_MUSIC).
* sampleRate: Data source sampling rate in Hz.
- * format: Audio format (e.g AUDIO_FORMAT_PCM_16_BIT for signed
- * 16 bits per sample).
+ * format: Audio format. For mixed tracks, any PCM format supported by server is OK
+ * or AUDIO_FORMAT_PCM_8_BIT which is handled on client side. For direct
+ * and offloaded tracks, the possible format(s) depends on the output sink.
* channelMask: Channel mask, such that audio_is_output_channel(channelMask) is true.
* frameCount: Minimum size of track PCM buffer in frames. This defines the
* application's contribution to the
flags = (audio_output_flags_t)(flags &~AUDIO_OUTPUT_FLAG_DEEP_BUFFER);
}
- if (audio_is_linear_pcm(format)) {
- mFrameSize = channelCount * audio_bytes_per_sample(format);
- mFrameSizeAF = channelCount * sizeof(int16_t);
+ if (flags & AUDIO_OUTPUT_FLAG_DIRECT) {
+ if (audio_is_linear_pcm(format)) {
+ mFrameSize = channelCount * audio_bytes_per_sample(format);
+ } else {
+ mFrameSize = sizeof(uint8_t);
+ }
+ mFrameSizeAF = mFrameSize;
} else {
- mFrameSize = sizeof(uint8_t);
- mFrameSizeAF = sizeof(uint8_t);
+ ALOG_ASSERT(audio_is_linear_pcm(format));
+ mFrameSize = channelCount * audio_bytes_per_sample(format);
+ mFrameSizeAF = channelCount * audio_bytes_per_sample(
+ format == AUDIO_FORMAT_PCM_8_BIT ? AUDIO_FORMAT_PCM_16_BIT : format);
+ // createTrack will return an error if PCM format is not supported by server,
+ // so no need to check for specific PCM formats here
}
// Make copy of input parameter offloadInfo so that in the future:
// Ensure that buffer alignment matches channel count
// 8-bit data in shared memory is not currently supported by AudioFlinger
- size_t alignment = /* mFormat == AUDIO_FORMAT_PCM_8_BIT ? 1 : */ 2;
+ size_t alignment = audio_bytes_per_sample(
+ mFormat == AUDIO_FORMAT_PCM_8_BIT ? AUDIO_FORMAT_PCM_16_BIT : mFormat);
+ if (alignment & 1) {
+ alignment = 1;
+ }
if (mChannelCount > 1) {
// More than 2 channels does not require stronger alignment than stereo
alignment <<= 1;
// there's no frameCount parameter.
// But when initializing a shared buffer AudioTrack via set(),
// there _is_ a frameCount parameter. We silently ignore it.
- frameCount = mSharedBuffer->size()/mChannelCount/sizeof(int16_t);
+ frameCount = mSharedBuffer->size() / mFrameSizeAF;
} else if (!(mFlags & AUDIO_OUTPUT_FLAG_FAST)) {