[CELT-dev] Raw CELT Bytes from the Command Line Interface

Bob Bang bob.bang2 at gmail.com
Wed Jun 1 10:34:55 PDT 2011

Well, my idea was to dump the input file's worth of CELT frames to a text
file, then parse the data given the known Packetsize number of bytes per
frame.  Since you know, for example, 40 bytes are in a frame, you could take
the first 40, then the next 40, etc etc.  This way I could model my
packetization, FEC and RF channel in Matlab.

My other option is to buffer up a much smaller amount of frames on a DSP and
dump those from memory to a text file. I was just hoping the command line
could get me to an easier solution with a larger number of frames available
to test.

I started looking into Ogg a bit more. I apologize, I assumed it was an Ogg
Vorbis file.  Now it makes more sense. I may try to go this route.

However, I will contest your statement that "raw CELT bytes" do not exist.
I've seen them with my own eyes.  :)

On Wed, Jun 1, 2011 at 12:13 PM, Benjamin M. Schwartz <
bmschwar at fas.harvard.edu> wrote:

> In a sense, there's no such thing as a stream of "raw CELT bytes".
> CELT can only be decoded after it's been broken into frames, and the frame
> boundaries cannot be determined by looking at the CELT data itself.  A
> transport layer such as Ogg or RTP is required to provide this framing
> information.
> In your case, the easiest solution might be to process the Ogg stream in
> order to retrieve the CELT frame data.  This is meant to be very easy;
> every Ogg player has to do it.  The obvious alternative would be to modify
> the command-line tools to export CELT using your own nonstandard framing
> scheme.
> --Ben
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