I would like to make lpcSize a multiple of 4. In the current library for narrow band mode lpcSize is currently set to 10. I would like to increase this 12 for optimization reasons. Is it a simple matter of just changing lpcSize in the structures in mode.c or are there other implications to doing this? I did try and change the value but I seem to be getting some runtime errors indicating a stack corruption. This seems to indicate that I am not allowed to just change the value in the struct. Is there a way for me to alter the lpcSize without having to rewrite sections of code? Thanks, Vasant Shridhar -------------- next part -------------- An HTML attachment was scrubbed... URL: http://lists.xiph.org/pipermail/speex-dev/attachments/20110411/77fbdb4f/attachment.htm
On 11-04-11 11:05 AM, Shridhar, Vasant wrote:> I would like to make lpcSize a multiple of 4. In the current library for > narrow band mode lpcSize is currently set to 10. I would like to > increase this 12 for optimization reasons. Is it a simple matter of just > changing lpcSize in the structures in mode.c or are there other > implications to doing this?Nothing major except you'd need to rewrite the LSP quantizer, retrain half the codebooks, change the bit-allocation and break compatibility with the format. Cheers, Jean-Marc
Okay, Not exactly the answer I was looking for. This sounds like a big change. I don't mind re-writing the LSP quantizer but re-training code books and breaking compatibility is not what I want to do. I am working on an optimization for an ARM cortex-A8. It is desirable to process things in 4 element blocks. Is there a simpler approach you could recommend? Vasant Shridhar ________________________________________ From: Jean-Marc Valin [jmvalin at jmvalin.ca] Sent: Monday, April 11, 2011 5:29 PM To: Shridhar, Vasant Cc: speex-dev at xiph.org Subject: Re: [Speex-dev] lpcSize On 11-04-11 11:05 AM, Shridhar, Vasant wrote:> I would like to make lpcSize a multiple of 4. In the current library for > narrow band mode lpcSize is currently set to 10. I would like to > increase this 12 for optimization reasons. Is it a simple matter of just > changing lpcSize in the structures in mode.c or are there other > implications to doing this?Nothing major except you'd need to rewrite the LSP quantizer, retrain half the codebooks, change the bit-allocation and break compatibility with the format. Cheers, Jean-Marc