Packets and m-blocks

GNU Radio
1

Greetings. Some time ago created a number of GNURadio signal
processing blocks for audio codecs, and have recently gotten around to
finishing them up for public release (Speex and CELT, along with the
speex acoustic echo canceler). Constant bitrate support was a piece
of cake (and wow does Speex sound better than GSM FR, I forgot how bad
GSM was… :wink: )

However, I’m stuck on supporting variable bitrate mode. I basically
want to present a variable sized packet interface for the coded side.
It seems that the m-block code is what I want to use for that … but
I can’t find any examples of m-block code that I could emulate. Can
someone kick me in the right direction?

2

Gregory M. wrote:

I can’t find any examples of m-block code that I could emulate. Can
someone kick me in the right direction?

Hi Gregory,

I don’t know if there is any way around this using the regular GNU Radio
blocks, m-blocks do allow variable sized messages in between blocks,
however there is no support for m-block->gr-block connections yet. I
believe Eric is scheduled to work on this soon. So in summary, yes the
m-blocks could solve your problem, but they are not ready for use with
the rest of the GNU Radio code base yet.

  • George