<titleabbrev="Interactive Audio Codec">Definition of the Opus Audio Codec</title>
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</author>
<dateday="14"month="March"year="2011"/>
<dateday="31"month="March"year="2011"/>
<area>General</area>
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<t>3: arbitrary number of frames in the packet</t>
</list>
For code 2, the TOC byte is followed by the length of the first frame, encoded as described below.
For code 3, the TOC byte is followed by a byte encoding the number of frames in the packet, with the MSB indicating VBR. In the VBR case, the byte indicating the number of frames is followed by N-1 frame
For code 3, the TOC byte is followed by a byte encoding the number of frames in the packet, with
bit 7 indicating VBR and bit 6 indicating that padding is inserted. In the VBR case, the byte
indicating the number of frames is followed by N-1 frame
lengths encoded as described below. As an additional limit, the audio duration contained
within a packet MUST NOT exceed 120 ms.
</t>
<t>
When padding is used, the number of bytes of padding is encoded in the following bytes. Values
from 0-254 indicate that 0-254 bytes of padding are included at the end. If the value is 255,
then the padding is 254 bytes, plus the padding value encoded in the next byte. By using code
255 multiple times, it is possible to add any amount of padding. The padding bytes produced by
the encoder MUST be zero, but the decoder MUST accept any value for the padding bytes.
</t>
<t>
The compressed size of the frames (if needed) is indicated -- usually -- with one byte, with the following meaning:
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<t>
Thanks to all other developers, including Raymond Chen, Soeren Skak Jensen, Gregory Maxwell,
Christopher Montgomery, Karsten Vandborg Soerensen, and Timothy Terriberry. We would also
like to thank Igor Dyakonov, Jan Skoglund and Keith Yan for their help in testing the
codec.
like to thank Igor Dyakonov, Jan Skoglund for their help with subjective testing of the
Opus codec. Thanks to John Ridges, Keith Yan and many others on the Opus and CELT mailing lists