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- #include "rtp-ext.h"
-
- // https://datatracker.ietf.org/doc/html/rfc6464
- /*
- The audio level header extension carries the level of the audio in
- the RTP [RFC3550] payload of the packet with which it is associated.
- This information is carried in an RTP header extension element as
- defined by "A General Mechanism for RTP Header Extensions" [RFC5285].
-
- The payload of the audio level header extension element can be
- encoded using either the one-byte or two-byte header defined in
- [RFC5285]. Figures 1 and 2 show sample audio level encodings with
- each of these header formats.
-
- 0 1
- 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5
- +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
- | ID | len=0 |V| level |
- +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
-
- Figure 1: Sample Audio Level Encoding Using the
- One-Byte Header Format
-
-
- 0 1 2 3
- 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
- +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
- | ID | len=1 |V| level | 0 (pad) |
- +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
-
- Figure 2: Sample Audio Level Encoding Using the
- Two-Byte Header Format
- */
-
- int rtp_ext_ssrc_audio_level_parse(const uint8_t* data, int bytes, uint8_t *activity, uint8_t *level)
- {
- if (bytes < 1)
- return -1;
-
- *activity = (data[0] & 0x80) ? 1 : 0;
- *level = data[0] & 0x7f;
- return 0;
- }
-
- int rtp_ext_ssrc_audio_level_write(uint8_t* data, int bytes, uint8_t activity, uint8_t level)
- {
- if (bytes < 1)
- return -1;
-
- data[0] = (activity ? 0x80 : 0) | level;
- return 1;
- }
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