Harsha- > U mean to say ITU test vectors will be having headders. I have to read that and > confirm which rate it is?? right.. > But,I did not found headder for g726 ITU test vector,, it is just straight forward > encoded data.. Microsoft has assigned several unique codes that identify compressed data stored in WAV files; these codes are stored at offset 2 in the WAV file header. Examples include G.711, G.723 ADPCM, GSM 6.10, etc. The idea is that Win Media player or other standard Win-compatible players (e.g. WinAmp) will play compressed WAV files correctly -- as long as the correct codec plug-in has been installed and matches with the assigned Microsoft IDs. Below is a web page below that lists some current codec ID assignments. As you can see, a number of speech codecs are included (scroll down to "fmt " section or search page for 'compression'): http://www.sonicspot.com/guide/wavefiles.html -Jeff > -----Original Message----- > From: Shrikanth Chandrashekar [mailto:] > Sent: Friday, July 02, 2004 8:55 PM > To: ; > Subject: Re: [speechcoding] G726 Header > > Harsha- > in general, the codec kernels are invoked with the following parameters, > 1. pointer's to in_ buffer, out_buffer > 2. Bitrate to be decoded/encoded. > 3. Frame_type > 4. Headers(for enc.-maybe) etc. > Most ITU testcases are categorized using bit-rates and frame-types andt > one common method is to use a simple wrapper function to read in the > header information from the first few-bytes of test-vectors and then > passing them on to the dec/enc kernel as distinct fields such as those > above. > > Ofcourse, multi-channel versions might demand more care especially > with memory allocation for the channel-specific data, workingbuffers > as they are generally assumed to be created and initialized appropriately > before the calling the codec. > > -Shrikanth > > ----- Original Message ----- > From: "Harsha H M" <> > To: <> > Sent: Friday, July 02, 2004 12:22 AM > Subject: [speechcoding] G726 Header > > > Hi > > > > I have implemented g726 decoder, but the thing is i do't have an header > for > > this i.e my thinking is if i give any encoded data it has to identify > to > > which rate it is encoded and it has to decode it.. I did not found this > info > > in ITU standard.mY CONFUSION IS LIKE DO I NEED TO WRITE MY WON HEADER > OR > > standard its self gives this info,, pls clarify my doubt.. i badly need > > this.. > > > > Thanks. > > Harsha |