Re: Problem while converting back to PCM

From: aihaug (aihaug_at_att.net)
Date: 03/23/04 

Date: Mon, 22 Mar 2004 21:15:04 -0500

I'm not sure that is the problem. I routinely use "0" for
acmConvertStream().
Rather, if your posted code is correct, you are passing an incorrect buffer
size
back into the GSM -> PCM conversion.

Look at the results of the first acmStreamConvert() call. The
cbDstLengthUsed
field tells you what the resulting output buffer size is. Whatever that
value is,
it should be your INPUT size to the decompress call, not 10240.
The decompression fails because this isn't a valid decompression frame size.

dan haug

"Chris P. [MVP]" <msdn@chrisnet.net> wrote in message
news:OTij27CEEHA.3080@TK2MSFTNGP10.phx.gbl...
> Mujtaba wrote:
> > hi we r working on internet telephony, where we have to to some data
> > format conversion from PCM to GSM and back. We r facing problem stated
> > below...
> >
> >
> >
> > We are using same buffers for conversion that is first we convert from
> > PCM to GSM and then back to the PCM from the resultant GSM buffer.
> > First conversion (PCM to GSM ) woks fine, while coverting back the
> > same buffer to PCM it return error code 512
> >
> > mr2 = acmStreamConvert (acmstream, &acmstreamhdr, 0);
> > //--------------------------------------------------------
> >
> >
> >
> > Could any body plz guide us about this problem
>
>
> Reading the documentation usually helps.
>
> Flags are important.
> ACM_STREAMCONVERTF_START
> ACM_STREAMCONVERTF_END
>
>

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