diff options
Diffstat (limited to 'vendor/github.com/pion/rtp/audiolevelextension.go')
-rw-r--r-- | vendor/github.com/pion/rtp/audiolevelextension.go | 60 |
1 files changed, 60 insertions, 0 deletions
diff --git a/vendor/github.com/pion/rtp/audiolevelextension.go b/vendor/github.com/pion/rtp/audiolevelextension.go new file mode 100644 index 0000000..f8701e1 --- /dev/null +++ b/vendor/github.com/pion/rtp/audiolevelextension.go @@ -0,0 +1,60 @@ +package rtp + +import ( + "errors" +) + +const ( + // audioLevelExtensionSize One byte header size + audioLevelExtensionSize = 1 +) + +var errAudioLevelOverflow = errors.New("audio level overflow") + +// AudioLevelExtension is a extension payload format described in +// https://tools.ietf.org/html/rfc6464 +// +// Implementation based on: +// https://chromium.googlesource.com/external/webrtc/+/e2a017725570ead5946a4ca8235af27470ca0df9/webrtc/modules/rtp_rtcp/source/rtp_header_extensions.cc#49 +// +// One byte format: +// 0 1 +// 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 +// +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +// | ID | len=0 |V| level | +// +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +// +// Two byte 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) | +// +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +type AudioLevelExtension struct { + Level uint8 + Voice bool +} + +// Marshal serializes the members to buffer +func (a *AudioLevelExtension) Marshal() ([]byte, error) { + if a.Level > 127 { + return nil, errAudioLevelOverflow + } + voice := uint8(0x00) + if a.Voice { + voice = 0x80 + } + buf := make([]byte, audioLevelExtensionSize) + buf[0] = voice | a.Level + return buf, nil +} + +// Unmarshal parses the passed byte slice and stores the result in the members +func (a *AudioLevelExtension) Unmarshal(rawData []byte) error { + if len(rawData) < audioLevelExtensionSize { + return errTooSmall + } + a.Level = rawData[0] & 0x7F + a.Voice = rawData[0]&0x80 != 0 + return nil +} |