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- #include "rtp-ext.h"
-
- // https://datatracker.ietf.org/doc/html/rfc6465
- /*
- The audio level header extension carries the level of the audio in
- the RTP 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 2 and 3 show sample audio level encodings with
- each of these header formats.
-
- 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=2 |0| level 1 |0| level 2 |0| level 3 |
- +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
-
- Figure 2: 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=3 |0| level 1 |0| level 2 |
- +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
- |0| level 3 | 0 (pad) | ...
- +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
-
- Figure 3: Sample Audio Level Encoding Using the
- Two-Byte Header Format
- */
-
- int rtp_ext_csrc_audio_level_parse(const uint8_t* data, int bytes, uint8_t levels[], int num)
- {
- int i;
- if (bytes < 1)
- return 0;
-
- for(i = 0; i < bytes && i < num; i++)
- levels[i] = data[0] & 0x7f;
- return i;
- }
-
- int rtp_ext_csrc_audio_level_write(uint8_t* data, int bytes, const uint8_t levels[], int num)
- {
- int i;
- if (bytes < num)
- return -1;
-
- for(i = 0; i < num; i++)
- data[i] = levels[i] & 0x7f;
- return num;
- }
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