Difference between revisions of "Bidirectional PAD communication protocol"
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For every audio frame, the ODR-AudioEnc checks if a block of PAD data is available by doing a nonblocking recv() on the UDP socket. If yes, it inserts it into the audio frame; if not, the audio frame will not contain PAD. In any case, it sends a request to ODR-PadEnc for new data: | For every audio frame, the ODR-AudioEnc checks if a block of PAD data is available by doing a nonblocking recv() on the UDP socket. If yes, it inserts it into the audio frame; if not, the audio frame will not contain PAD. In any case, it sends a request to ODR-PadEnc for new data: | ||
| − | UDP PAD Request | + | UDP PAD Request - message format |
| − | | | + | | type (1 byte) | |
| − | | 0x1 | + | | 0x1 (request) | |
ODR-PadEnc prepares the PAD block and answers with a UDP reply message: | ODR-PadEnc prepares the PAD block and answers with a UDP reply message: | ||
| − | UDP PAD Reply | + | UDP PAD Reply - message format |
| − | | | + | | type (1 byte) | PAD data (N bytes) | |
| − | | | + | | 0x2 (reply) | <PAD> | |
| + | |||
| + | Future versions of the messages as well as new types of messages shall use different values for the type field. | ||
| + | |||
| + | |||
| + | Multi-byte values (none yet) use network endianness (i.e. big-endian). | ||
TODO: | TODO: | ||
* Define the order of bytes for the PAD data | * Define the order of bytes for the PAD data | ||
| − | |||
| − | |||
Revision as of 13:59, 6 February 2017
The current ODR-PadEnc to ODR-AudioEnc communication is done through a nonblocking FIFO.
The proposal is to replace it by a UDP-based request/reply protocol.
For every audio frame, the ODR-AudioEnc checks if a block of PAD data is available by doing a nonblocking recv() on the UDP socket. If yes, it inserts it into the audio frame; if not, the audio frame will not contain PAD. In any case, it sends a request to ODR-PadEnc for new data:
UDP PAD Request - message format | type (1 byte) | | 0x1 (request) |
ODR-PadEnc prepares the PAD block and answers with a UDP reply message:
UDP PAD Reply - message format | type (1 byte) | PAD data (N bytes) | | 0x2 (reply) | <PAD> |
Future versions of the messages as well as new types of messages shall use different values for the type field.
Multi-byte values (none yet) use network endianness (i.e. big-endian).
TODO:
- Define the order of bytes for the PAD data
