Comments on: Speech Codecs Library http://alax.info/blog/51 Software Production Line Thu, 20 Nov 2008 18:48:35 +0000 http://wordpress.org/?v=2.6.3 By: alax http://alax.info/blog/51#comment-5629 alax Tue, 20 May 2008 09:18:33 +0000 http://alax.info/blog/51#comment-5629 Jaisonkim, as far as I remember, DirectShow wold provide ACM conversion filter to convert to/from PCM 16 KHz sample rate if hardware does not support this format. I wold rather say that the problem is in AM_MEDIA_TYPE you enumerate and/or accept on the pins of your filter. Can you re-check everything is OK there? Jaisonkim, as far as I remember, DirectShow wold provide ACM conversion filter to convert to/from PCM 16 KHz sample rate if hardware does not support this format. I wold rather say that the problem is in AM_MEDIA_TYPE you enumerate and/or accept on the pins of your filter. Can you re-check everything is OK there?

]]> By: jaisonkim http://alax.info/blog/51#comment-5628 jaisonkim Tue, 20 May 2008 08:54:59 +0000 http://alax.info/blog/51#comment-5628 i am trying to make G.722.1 DMO filter according to your example. But the problem is audio capture filter. The input pin of G.722.1 DMO filter should be 16KHz, 16Bit, mono. I can not set the audio capture filter output pin to that value. Mostly audio capture filter in Window doesn't provide 16KHz, 16Bit audio, does it ? Your comment is highly appreciated. i am trying to make G.722.1 DMO filter according to your example. But the problem is audio capture filter.
The input pin of G.722.1 DMO filter should be 16KHz, 16Bit, mono.
I can not set the audio capture filter output pin to that value.
Mostly audio capture filter in Window doesn’t provide 16KHz, 16Bit audio, does it ?
Your comment is highly appreciated.

]]> By: alax http://alax.info/blog/51#comment-5620 alax Wed, 02 Apr 2008 17:11:07 +0000 http://alax.info/blog/51#comment-5620 It was over two years ago and I used IPP 5.1 AFAIR which was quite different in interface from IPP 5.2 and 5.3 released later (hopefully there will be no major changes in coming IPP 6.0). So my speech codecs code does not compile right now with IPP 5.3 installed. The idea was that IPP implemented codecs use common USC interface implemeted by Intel. From you description it looks like you are losing some data buffers and receive noise instead of data. In IMediaObject::ProcessInput I saved a reference to provided buffer and in IMediaObject::ProcessOutput I used the buffer to pass atomic data buffers to IPP and use returned data to fill output buffers. I suggest that you put a breakpoint on USC_Fxns* Decode function call and check what are you pushing as input and what you are getting as output. P.S. I edited your post to hide email. It was over two years ago and I used IPP 5.1 AFAIR which was quite different in interface from IPP 5.2 and 5.3 released later (hopefully there will be no major changes in coming IPP 6.0). So my speech codecs code does not compile right now with IPP 5.3 installed.

The idea was that IPP implemented codecs use common USC interface implemeted by Intel.

From you description it looks like you are losing some data buffers and receive noise instead of data.

In IMediaObject::ProcessInput I saved a reference to provided buffer and in IMediaObject::ProcessOutput I used the buffer to pass atomic data buffers to IPP and use returned data to fill output buffers.

I suggest that you put a breakpoint on USC_Fxns* Decode function call and check what are you pushing as input and what you are getting as output.

P.S. I edited your post to hide email.

]]> By: hannes.lippet http://alax.info/blog/51#comment-5619 hannes.lippet Wed, 02 Apr 2008 12:12:41 +0000 http://alax.info/blog/51#comment-5619 forgot my email: h***@l***.de forgot my email: h***@l***.de

]]> By: hannes.lippet http://alax.info/blog/51#comment-5618 hannes.lippet Wed, 02 Apr 2008 11:25:43 +0000 http://alax.info/blog/51#comment-5618 Hi there, i am doing almost the same thing right now and i am running in some problems here. I need to Decode G726 Data in Directshow. So i wrote a DMO that uses the Intel IPP (5.3) in C# with Visual Studion 2005. That worked quite ok, but the calls to the IPP just dont seem to do the right thing.No Errormessage, but only noise in the speaker. Can you give me some advice how you used the IPP g.726 gecoder? thank you hannes Hi there,

i am doing almost the same thing right now and i am running in some problems here.

I need to Decode G726 Data in Directshow. So i wrote a DMO that uses the Intel IPP (5.3) in C# with Visual Studion 2005. That worked quite ok, but the calls to the IPP just dont seem to do the right thing.No Errormessage, but only noise in the speaker. Can you give me some advice how you used the IPP g.726 gecoder?

thank you
hannes

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