ask for help on Hi Fidelity Audio Compression with ADPCM

Started by Jessecw in comp.dsp11 years ago 3 replies

Hi all, Currently, I am studying on how to get Hi Fidelity effects with ADPCM related compression methods. But it seems that the...

Hi all, Currently, I am studying on how to get Hi Fidelity effects with ADPCM related compression methods. But it seems that the traditional IMA ADPCM and MS ADPCM will not get the satisfied results. Any one can give me some suggestions? 16 bit PCM to 5 bit PCM will be accepted by me. Thanks in advance. Jessecw


ask for help on Hi Fidelity Audio Compression with ADPCM

Started by jessecw in comp.dsp11 years ago 2 replies

Hi all, Currently, I am studying on how to get Hi Fidelity effects with ADPCM related compression methods. But it seems that the...

Hi all, Currently, I am studying on how to get Hi Fidelity effects with ADPCM related compression methods. But it seems that the traditional IMA ADPCM and MS ADPCM will not get the satisfied results. Any one can give me some suggestions? 16 bit PCM to 5 bit PCM will be accepted by me. Thanks in advance. Jesse


adpcm code

Started by jagadeesh676 in comp.dsp10 years ago 1 reply

Hi There, I have been searching for the Matlab code for 40, 32, 24, 16 KBits/s ADPCM code (G.726) for the last one week but could not find a...

Hi There, I have been searching for the Matlab code for 40, 32, 24, 16 KBits/s ADPCM code (G.726) for the last one week but could not find a good working/ compliant code. Can anyone tell me where to get free version of the ADPCM code in Matlab Thanks, jagadeesh


ADPCM Matlab Code

Started by Anonymous in comp.dsp11 years ago

Hi There, I have been searching for the Matlab code for 40, 32, 24, 16 KBits/s ADPCM code (G.726) for the last one week but could not find a...

Hi There, I have been searching for the Matlab code for 40, 32, 24, 16 KBits/s ADPCM code (G.726) for the last one week but could not find a good working/ compliant code. Can anyone tell me where to get free version of the ADPCM code in Matlab compliant to the G.726 standard? Thanks, Farhan


switched ADPCM

Started by Jessecw in comp.dsp11 years ago 3 replies

Hi All, I am preparing to develop an real time audio compression codec for high quality audio signals. Due to the heavy calculation burden, I...

Hi All, I am preparing to develop an real time audio compression codec for high quality audio signals. Due to the heavy calculation burden, I will not adopt MP3 as my compression algorithm. I get from google search engine that there is an algorithm called switched ADPCM that can code high quality audio signals. I would like to hear from some one that what switch ADPCM is or get some u...


ADPCM Wav File Specification

Started by dbell in comp.dsp10 years ago 4 replies

Hello Everybody, Does anyone know where to find a detailed algorithm description for Wav file compatible ADPCM? Thanks, Dirk

Hello Everybody, Does anyone know where to find a detailed algorithm description for Wav file compatible ADPCM? Thanks, Dirk


number of ADPCM channels in E1 ???

Started by sahar in comp.dsp12 years ago 4 replies

Hi fellows im newcomer . could anyone reply to my Question please .... How many ADPCM channels are transmitted in E1 (2mb) stream if the...

Hi fellows im newcomer . could anyone reply to my Question please .... How many ADPCM channels are transmitted in E1 (2mb) stream if the bitrate is 40kbps , 32kbps , 24kbps, 16kbps Is their any standard frame structure for it as their is for PCM . Kindly help me out With regards Sahar This message was sent using the Comp.DSP web interface on www.DSPRelated.com


G.722 ADPCM Help

Started by Al Clark in comp.dsp13 years ago 2 replies

We have an application that uses a sub band ADPCM (G.722) coder and decoder. Our goal is data reduction with good quality, minimal computation...

We have an application that uses a sub band ADPCM (G.722) coder and decoder. Our goal is data reduction with good quality, minimal computation overhead and extended speech bandwidth. We chose G.722 because we didn't want to reinvent the wheel and it appeared to be a good candidate. We have several examples in C (Embree) and asm (ADI 21xx) and none of them give answers that make sense (a...


.wav-> G.723

Started by learningdsp in comp.dsp13 years ago 3 replies

Hello, I am a beginner and trying to understand the working of G.723 ADPCM. I have been able to get all the C files from ITU for the G.723...

Hello, I am a beginner and trying to understand the working of G.723 ADPCM. I have been able to get all the C files from ITU for the G.723 ADPCM. I have a basic question. According to the documentation and block diagram the first block converts the input signal from linear or A-law or U-law to uniform PCM signal. Then come the next steps of finding the difference signal, etc.. I ha...


ADPCM g.722 old ADI Code

Started by Al Clark in comp.dsp13 years ago 6 replies

There is some g.722 ADPCM code in the Digital Signal Processing Applications Using the ADSP-2100 Family book. Does anyone know if it actually...

There is some g.722 ADPCM code in the Digital Signal Processing Applications Using the ADSP-2100 Family book. Does anyone know if it actually works? We are translating the code into a newer DSP and we think we have found some mistakes. Can anyone point to some working sample code, examples, etc. (I know where to buy the standard)? -- Al Clark Danville Signal Processing, Inc. ----...


Interpolated ADPCM

Started by zhoujinxi in comp.dsp10 years ago 2 replies

Hi all, I am developping an real time audio compression codec system.In my system I adopted 16-bit 48kHz to 5 bit 48kHz IMA-ADPCM algorithm,but...

Hi all, I am developping an real time audio compression codec system.In my system I adopted 16-bit 48kHz to 5 bit 48kHz IMA-ADPCM algorithm,but could not get the satisfied results,audio result was not good. I know from someone,there is an tech call "interpolated" will do the job. I would like to hear from some one how to work with interpolated or get some useful web URL for it. Thanks...


distinguishing file formats in libsndfile

Started by monteiro in comp.dsp13 years ago 3 replies

Hi, I was using libsndfile to read files encoded in g.726(is it alright to do so?) and write them to an oki adpcm at 6k. the problem is that...

Hi, I was using libsndfile to read files encoded in g.726(is it alright to do so?) and write them to an oki adpcm at 6k. the problem is that libsndfile only accepts a combo of au and g.721 and my encoded file are headerless. any ideas about how to work around this problem? Thanx in advance, Joy.M.Monteiro


G.729 with different sampling rates?

Started by Jack in comp.dsp13 years ago 12 replies

I'm trying to understand G.729. The only compression algorithm I've coded before is ADPCM, and it wasn't keyed to a certain sampling rate - that...

I'm trying to understand G.729. The only compression algorithm I've coded before is ADPCM, and it wasn't keyed to a certain sampling rate - that is, it would be just as happy with 8100 samples per second or 7900 samples per second as it would have been with 8000, just the quality would be slightly higher or lower. With G.729, all the documentation refers to a sampling rate of 8 KHz. Is it ...


VDVI and DVI4

Started by Steve Underwood in comp.dsp11 years ago

Hi all, RFC3551 defines the way in which the output from a number of codecs should be packed into RTP packets. Amongst these is the DVI ADPCM...

Hi all, RFC3551 defines the way in which the output from a number of codecs should be packed into RTP packets. Amongst these is the DVI ADPCM codec, commonly found on PCs. They refer to this as DVI4. Also, there is VDVI, which is a kind of run length encoded variable bit rate version of DVI. They quote some low potential numbers for its bit rate, which don't seem to make sense. The 4 ...


Channel Coding: approximation instead of correction

Started by dudelmann in comp.dsp8 years ago 8 replies

Hi all I am implementing an ADPCM codec for use in wireless transmissions (as frequent blog visitors may already know :). I have a question...

Hi all I am implementing an ADPCM codec for use in wireless transmissions (as frequent blog visitors may already know :). I have a question regarding channel coding for the wireless channel. All the codes I know have error detection and (some) error correction capabilities. So far so good. But for audio transmission I don't really need to get the exact transmitted values. I don't care if the...


[Q]Audio processing technique to increase speech quality?

Started by Anonymous in comp.dsp10 years ago 16 replies

Hi, I am in a process to improve the speech quality out of our current speech codec. Basically, our speech codec is an ADPCM codec with...

Hi, I am in a process to improve the speech quality out of our current speech codec. Basically, our speech codec is an ADPCM codec with bunch of interpolation and decimation filters and Sigma-Delta ADDA, and we have already adjusted all the filters so now it works just fine. However, we are still not 100% satisfied with the audio quality, we want to make the sound more clear so we are thin...


[Q]Audio processing technique to increase speech quality?

Started by Anonymous in comp.dsp10 years ago 1 reply

Hi, I am in a process to improve the speech quality out of our current speech codec. Basically, our speech codec is an ADPCM codec with...

Hi, I am in a process to improve the speech quality out of our current speech codec. Basically, our speech codec is an ADPCM codec with bunch of interpolation and decimation filters and Sigma-Delta ADDA, and we have already adjusted all the filters so now it works just fine. However, we are still not 100% satisfied with the audio quality, we want to make the sound more clear so we are thin...