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Subject: Re: how to merge fixed point wma decoder to libav 0.7.6

Re: how to merge fixed point wma decoder to libav 0.7.6

From: Diaz Soho <>
Date: Fri, 12 Sep 2014 11:32:25 +0800

Hi Mike,

Thanks a lot for your input!!
I have merge the code into ffmpeg libavcodec, and the flow is refered from
wma.c that you mentioned.
but I got a problem.
the function ff_imdct_calc cause SIGSEGV error (memory access error in
linux )when decode audio data ,
do you have any idea?

2014-09-12 3:29 GMT+08:00 Mike <>:

> Could you explain more detail about your idea?
> since I have question about how to decode wma file.
> the container used for wma file is ASF, how to demux asf in Rockbox?
> the data that read by asf_read_packet (to read an ASF packet) can be put
> into decode ,right?
> that does not include container data?
> Could you kindly give the hints?
> You can demux an ASF packet by calling asf_read_packet, which will give
> you (IIRC) enough compressed data to decode at least one superframe.
> If you haven't already, take a look at wma.c. I didn't write most of that
> code, but the logic looks fairly clear (call asf_read_packet, pass data
> to the decoder, repeat until out of data).
> Mike
Received on 2014-09-12

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