shithub: opus

Info  •  Files  •  Log  •  Branches

Ogg Opus draft: Address chair review comments.

1. Removed an inappropriate normative MAY.
2. Gave an explicit range of sample rates deemed to be "non-crazy".
3. Give explicit guidance on packet sizes that SHOULD and MAY be rejected.

--- a/doc/draft-ietf-codec-oggopus.xml

+++ b/doc/draft-ietf-codec-oggopus.xml

@@ -101,7 +101,7 @@

  stream, to aid seeking.

 A single page can contain up to 65,025 octets of packet data from up to 255

  different packets.

-Packets MAY be split arbitrarily across pages, and continued from one page to

+Packets can be split arbitrarily across pages, and continued from one page to

  the next (allowing packets much larger than would fit on a single page).

 Each page contains 'lacing values' that indicate how the data is partitioned

  into packets, allowing a demuxer to recover the packet boundaries without

@@ -667,6 +667,10 @@

  implementations which do something with this field SHOULD take care to behave

  sanely if given crazy values (e.g., do not actually upsample the output to

  10 MHz if requested).

+Input sample rates between 8 kHz and 192 kHz (inclusive) SHOULD be

+ supported.

+Rates outside this range MAY be ignored by falling back to the default rate of

+ 48 kHz instead.

 <vspace blankLines="1"/>

 </t>

 <t><spanx style="strong">Output Gain</spanx> (16 bits, signed, little

@@ -1262,10 +1266,10 @@

  bitrate (VBR) stream constant bitrate (CBR).

 Decoders SHOULD avoid attempting to allocate excessive amounts of memory when

  presented with a very large packet.

+Decoders SHOULD reject packets larger than 60 kB per channel, and display

+ a warning message, and MAY reject packets larger than 7.5 kB per channel.

 The presence of an extremely large packet in the stream could indicate a

  memory exhaustion attack or stream corruption.

-Decoders SHOULD reject a packet that is too large to process, and display a

- warning message.

 </t>

 <t>

 In an Ogg Opus stream, the largest possible valid packet that does not use