similar to: data reduction on Vorbis

Comments? ---------------------------------------- "Mark Taylor" <mt@sulaco.org> wrote: [...] > This is related to one minor objection I have to vector quantization > based codecs like Vorbis and the MPEG4 VQ codec: they do not compute > the quantization noise during the encoding process. The choice of > codebooks (use a big codebook: low quantization noise, use a

[Apologies if this gets through twice. I sent it first without subscribing, but it seems like it got stuck in the moderation queue, so I subscribed and re-sent it.] I'm doing some work on audio fingerprinting for a school project (more precisely, my master's thesis. I got a hint on #vorbis that I might want to look into the internal floor representations in libvorbisenc to get out audio

Hi, I'd like to contribute to Vorbis and I think this may be of some interest for low bitrate coding. I have been experimenting with low bit-rate coding for the high-band (11 kHz to 22 kHz) and, though I haven't yet started quantizing my coefficients (a gain and an LPC filter), I expect to be able to approximate the whole 11-22 kHz band with around 1000 bits/s per channel (maybe even 500

Hi I have gone through the document available in the net regarding the Vorbis encoder /Decoder. Based on that i have prepared a understanding document on the encoder/decoder block. I would like to know whether my understanding of the coder is OK. If there are any other additional block /information pl. provide me with the same. Thanks and regards S.Padmashri <HR NOSHADE> <UL>

[ I'm not in the list because I didn't find a digested version; please move the lists to sourceforge.net, and we would have the digested version. I read the replies from the archive. ] Hello. Would it be possible to allow Vorbis use the same codebook for multiple files? I could keep a 650 MB codebook on CD-R and use that for all my audiofiles. If that is possible, how much the

I've made a block diagram of the encoder because I tried to find out, how it works http://stoffke.freeshell.65535.net/ogg/block.html Although there are specifiation docs, that give very detailed information about single aspects of the encoding (or decoding) , I'm missing documenations that give a more general overview, about how the encoder works. (Vorbis Illuminated seems a bit

Hello vorbis developer! I'm not very experienced in informatics, cause i'm only an audio engineer and sorry for my broken english but i have an idea... After the filterbank the maximum aplitude in each band decides about the nessesary bits, then the psychoacoustic model decides how much of the signal can be truncated without hearable noise. What do you think about quantising the

Hi. I have been talking with Psytel MPEG-4 AAC developer (www.psytel.com) about various compression formats, and to make it short he said that one of the main drawbacks of Vorbis is its vector quantization - it introduces more error then other quantization methods (like non-uniform scalar quantization, if I got it right), probably used in AAC and other similar codecs. I know vector quantization

(This is almost out of topic but anyway...) It is surprising how little research effort have been put into psy-acou models for CELP. The basic problem lies in that it is not easy to alter the LP model without distroying the minimum-phase property (ie. the stability of the predictor). That leaves us with psy-acou modelling of the noise-part only. However, my own research is in constrained

Hello! I'm an Italian student in computer engineering (University "Federico II" of Naples) and I have to write my graduation thesis in the field of signal processing. My teacher (Prof. Giovanni Poggi http://www.diet.unina.it/giovanni.poggi/) has published a research about multiple description vector quantizers by means of the self organizing maps, applying his idea to the images and

Hi, Check it out-- another update in the space of a week: http://home.pcisys.net/~melanson/codecs/vp3-format.txt v0.4: March 2, 2004 - renamed and expanded section "Initializing The Quantization Matrices" - outlined section "Reconstructing The Frame" - moved Theora Differences Appendix to its own section entitled "Theora Specification" - added Appendix:

On Mar 29, 2007, at 12:44, Harry Sack wrote: > 2007/3/29, Josh Green <josh@resonance.org>: > As far as I know 24 bit FLAC support is broken. It often doesn't > compress the audio at all, but instead stores the chunks as verbatim > type (although the FLAC format supports 24 bit). Perhaps this is > fixed? > If so, do let me know. > > I also want to know if this

We've implemented a vorbis decoder based on Tremor and as part of the documentation we're also writing about psycho acoustic models and encoding. We're quite up to date with the decoding process and psycho acoustics in general but unfortunately not on the psycho acoustic encoding used in Vorbis. We have a few questions that would we would be very thankful to have answer to: Which

I intend to finish my Vorbis document on Monday so I will leave it over the weekend to see if there are any more modifications suggested. Although the document will be internal I will put a copy of the final version at the same address - I know firsthand how annoying it is to find loads of dead links when trying to find background info on Vorbis (I know google has probably already got a link

-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 Dear Celts, I've become intrigued by the problem of spherical quantizers, so I decided to see if I could come up with something better than PVQ. What I wound up writing is something I call an "octagon quantizer. In two dimensions, PVQ uses a "diamond" (square) shape. An octagon code (OVQ) uses an octagon, which is a much better

Hi, I am using speex 1.2beta2 on a 24bit DSP that has a severe program and data space limitations. I am only interested in the speex decoder for 11kbps narrowband implementation. I am using the following parameters and structures 160, /*frameSize*/ 40, /*subframeSize*/ 10, /*lpcSize*/ 17, /*pitchStart*/ 144, /*pitchEnd*/ /* 11 kbps medium bit-rate

I have some data measured with a coarsely-quantized clock. Let's say the real data are q<- sort(rexp(100,.5)) The quantized form is floor(q), so a simple quantile plot of one against the other can be calculated using: plot(q,type="l"); points(floor(q),col="red") which of course shows the characteristic stair-step. I would like to smooth the quantized

Hello, I have finally added 2 lower quality settings for the NHW codec: -l1 (-5Ko) and -l2 (-10Ko).I use a quantization of 0.935 and 0.88 (kind of quantization), and I decrease residual coding on the first order wavelet image. I have updated the demo page: http://nhwcodec.blogspot.com/ . These 2 lower quality settings are still experimental.If you could find time, would be interested in any

-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 So you're the encoder. Tou get two vectors in (for some band), L and R. One thing you could do with this is compute M = L+R and S = L-R. (Yes, I know, this is not how the encoder actually works. Bear with me.) Then let m = normalize(M) and s = normalize(S). You transmit, m, s, |L|, and |R|. The decoder needs to find unknown positive constants

Hello people, Looks like Santa Claus thinks I've been a good boy this year. Here's the third in my performance patch series: d.m.l Apply after applying d.o.n and d.n.m; I don't know how much of those got applied to the CVS tree. What's inside: Request for help! Look in os.h if you're using a compiler or processor I don't use (I use gcc on K5, K7, G3). New MDCT! Now we