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The characteristic UUID shall be set to: TBD
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Both G.726 and IMA/DVI ADPCM Frames shall be 100 octets in length; consisting of 96 octets of encoded audio sample data and 4 octets of metadata.
Figure 5 shows the layout of an audio frame and the how it is sent in 20 octet GATT notifications.
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The 4 octet meta data header contains information to be used by the decoder, Table below shows the format of the meta data.
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Figure below shows the layout of the start of an ADPCM audio frame.
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Audio data is always buffered in 100 octet frames, and the device shall ensure that only complete frames are sent (as 5 x 20 octet GATT notifications). No partial frames shall ever be transferred. This ensures that the STB host can always determine where an audio frame starts and ends. The RVS Server shall be able to buffer a minimum of 2 audio frames. If frame buffers are exhausted then the complete frame shall be discarded, however the frame sequence number should still be incremented for the next encoded frame. All buffered content shall be purged when either a disconnection event occurs, audio streaming is disabled via the Audio Control Characteristic or notifications are disabled for the characteristic.
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