similar to: Cascading?

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

Go monty! jack. ----- To: cvs@xiph.org Subject: [xiph-cvs] cvs commit: vorbis/vq huffbuild.c latticetune.c make_residue_books.pl Date: Sun, 3 Jun 2001 22:50:13 -0700 (PDT) From: xiphmont@xiph.org (Monty) Precedence: bulk Reply-To: cvs@xiph.org xiphmont 01/06/03 22:50:12 Modified: lib codebook.c codebook.h floor0.c mapping0.c os.h res0.c vq

Hi folks, My wife and I are taking a long weekend to celibrate our anniversary. I won't be around again until Wednesday to answer email or do anything else on Vorbis. Yeah, I know, I usually answer my email once a month anyway (so likely no one would notice me being gone), but just so folks know if anything really juicy comes up :-) I'll be merging my latest branch with mainline

Hi, From the vorbis decoder specification, it is clear that the decoder needs to have all the codebooks before decoding can actually begin. I will appreciate if someone can clear the following questions: 1. I guess the codebooks are derived from the actual input data. Probably the encoder may be making two passes through the input. The first pass finds out the frequency of different symbols

Hi, Does anybody know how codebooks are generated in OggVorbis encoder? We are porting oggorbis encoder on embedded platform for which VQ codebook memory is hugeeee to imagine. How can we reduce that? Can we do VQ with less codebooks and if yes how? If any help available? Parul Embedded Engineer Einfochips Ltd

Hi, I am a bit confused on how code-words are derived from the codeword lengths. I will appreciate if someone can point me in the correct direction. I will take the example of an actual codebook that i found in a valid vorbis encoded file as shown below. [SK] +------Codebook [0] -------- [SK] Codebook Dimensions = 1 [SK] Codebook Entries = 8 [SK] Unordered [SK] 1, 6, 3, 7, 2, 5, 4, 7, [SK] NO

Hello, I am a grad student in the Music Engineering Technology program at the University of Miami. I am planning on doing thesis research on cascading audio encoding chains and how to eliminate or improve audible artifacts in future encoding generations and will potentially be using Ogg for this work. My specific question is, Has anyone done any prior work in cascading audio encoders? If so, it

Hello folks, The codebook infrastructure for Vorbis is now well underway. This is it! The last piece needed for *real* bitstreams. To that end, I have a decent VQ codebook generator running. I was originally using some farily typical merge/split algorithms and then decided that the right way to do this was to model a VQ codebook as an m-dimensional set of bubbles (like a foam). I know there

Hi, I am trying to implement ogg vorbis real time decoder on SHARC ADSP 21364 processor. I am writing my own version of the decoder using the documentation vorbis_I_spec.pdf from xiph.org. However I am facing certain hurdles in floor curve decoding during audio packet decode. In the spec it says that [cval] = read from packet using codebook number [so and so] in *scalar context*.(page no 43).

Hi, We are porting the Ogg Vorbis fixed point decoder to a 24 bit fixed point precision processor. We are trying to reduce the number of cycles for MIPS optimization. In this process we observed that most of the songs do not have "maximum codeword length" greater than 24 bits. We are planning to reduce most of the double word operations (in our case 32 bit data is stored as double

In my model I have a city_id. ON the form I am using a cascading select to select the state, which then does a remote_submit to get the list of cities (and hence the city_id) for the selected state. The problem that I am having is that if I make a selection, hit SUBMIT and validation fails, the original selected state/city is now reset (ie, the values aren''t saved). Since they

I was just somewhat curious as to what lossless compression is used... is it just huffman? Tony Arcieri --- >8 ---- List archives: http://www.xiph.org/archives/ Ogg project homepage: http://www.xiph.org/ogg/

Hello! First of all a question: When you make the encoder tables (ie: mode_e.h) do you use the mapping0_forward function? Because you made the encoder tables, and after this you did a minor correction in the final beta4 ... (this correction was: additional[0]=fabs(additional[0]*scale); in the mapping0_forward function) (I see this was a bug, and the modification was correct, but this correction

Hi, I would like to ask if someone couldhelp me. I am writing a decoder for ogg-vorbis. I am not using the libvorbis because we want a code using our memory functions and I am going to rip some of the decoder functionality as we want only to use mono, 44.100, 96-160kbs sound files. We want to write the fastest and cleanest code possible even using assembler functions where possible. I have

Hi all, I'm porting the Tremor code to an ARM platform. Unfortunately, we didn't use the low mem branch code for CPU performance consideration, and now I find the memory use in it is huge for the embedded system. After looking into the code, I found the header parse, especially, the codebook unpack part takes a lot of memory. Tremor decodes the codebooks to a cache to store

alpha. (that about sums it up) Will encode and play back via an sdp file and multicast on one computer (over the net if you transfer the sdp file over by hand). rc/rtenc3 and src/rtdec3 are in the style of encoder/decoder_example ...so this means you MUST edit it them to suit your system. For example, I specify my rtenc3 to multicast just on eth1 (to avoid pissing off my cable supplier on

Hi folks, I'm doing a merge of my current branch onto the mainline (for testing) today. I believe it to be stable. Just a little more vorbisfile testing. After the merge, I have a few more patches to apply, then onto cascading/coupling. New stuff: Floor backend 1 and residue backend 1; both are present, but the mainline modes won't use either yet. Naturally, both are enabled for

Hello Monty, Sorry for the wrong subject title last time. A little more clarification needed. When reading bit-by-bit, there is no MSb/LSb, just 'first bit' and 'last bit'. The Huffman tree is traversed from 'first bit' to last bit'. This is a conceptual layer above the bitpacker; all you need to know is what order the bits come out, which happens to be LSb-first.

I'm trying to understand the residuevqtrain program, and I have some questions for Monty, Erik, or anyone that understands how it's supposed to work. I captured TRAIN_RES data from an encoding of a single track (about 4:43), producing two files, residue_0.vqd (3727 lines, = 3727 points?) and residue_1.vqd (huge). I then did a run with the parameters from the usage message

hello all, we are developing and porting vorbis1decoder on a 24 bit platform. in the process we came across somedoubts about node bytes and leaf words. from the specification we got that we are arranging the huffman codeword tree into an array. the nodebytes are the number of bytes that are required to represent a node and leafwords are the no. of bytes required to represent the leaf i.e the