search for: codebooks

The VQ codebook generation utilities are more or less ready to go. Minor things are left to do, but those will have to be handled as I to them :-) The next thing to do is complete the interface to get compression modes and codebooks to the library for encoding (minor stuff), and then arrange how exactly the MDCT residue is filtered through the codebooks. VQ codebook util instructions: *********** Input data: First, ya gotta have a data set to train a codebook on. Training data files are text files of comma delimited value...

The following has been committed to the Vorbis I spec as of r19445: Errata 20150226: Single entry codebooks A ?single-entry codebook? is a codebook with one active codeword entry. A single-entry codebook may be either a fully populated codebook with only one declared entry, or a sparse codebook with only one entry marked used. The Vorbis I spec provides no means to specify a codeword length of zero, an...

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

...nfortunately, 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 them for further decode. And this is the dominant factor in decoder memory usage, am I right? There are two structures in this code to hold the codebooks, static_codebook and codebook. But in low mem code, there are only one structure - codebook. It seems static_codebook...

Hi guys, This is my first post, I?m a brazilian programmer and I think speex is a great project. :) I'm working on a free software project and I was planning to use speex on it. I have used the java speex version in another project and that worked well, and this time I was planning to use a JNI version to get the latest features. ok, lets get to the point. :) I would need to mix some audio

Hi, Please brace yourselves for some possibly stupid questions. Why are there only 2 codebooks for floors and many more for residue values? What makes the encoding of floor values fundamentally different from encoding residue values? I have a basic understanding of VQ, and looking at the floor decode function, it all makes sense 1) Read the codebook index from the stream 2) D...

...n Vorbis (for now) is used to encode both the LSP coefficients (for the spectral envelope) and the MDCT coefficient residue after removing the spectral envelope. Either/both may be VQ/Huffman/etc; Vorbis does not distinguish between the special cases of the codebook mechanism. On the decode side, codebooks all look alike (and strictly speaking, the proper route is only to spec a decoder and let the encoder do anything it wants to produce a valid stream). *** 3) It just so turns out that to keep complexity down for now, the encoder will use VQ (with fixed or variable length codewords) for all encodin...

Hi, Am I correct in understanding that the codebooks are *not* adaptive during compression? I see that Packet #3 is written to the stream in the beginning of the encode process with no modification. If the codebooks are not adaptive, then why are codebooks included in the stream at all? Why not pass the mode type (A or B or C...) instead of all th...

Anexed is my function for reading codebooks and the Vq Table. My problem is: I read a codeBook number of 41, so i called this function above 41 times. The firtst time, the sync patterns (BCV) is alligned correctly, so it reads correctly. the sencond time it is executed, the patter is not there anymore and there are only 8 BCV in my file....

heh...:) maybe I?ll just answer "the number is 42". ;) well... some guys did mixing using *G.722 *encoded frames... maybe we could ask them: 8P http://ieeexplore.ieee.org/Xplore/login.jsp?url=/iel5/4054516/4054517/04054870.pdf?isnumber=4054517&prod=CNF&arnumber=4054870&arSt=2045&ared=2048&arAuthor=G.+Agnello%3B+R.+M.+Dansereau and a little off-topic, but fun for

Often it is useful to keep a "codebook" to document the contents of a dataset. (By "dataset" I mean a rectangular structure such as a dataframe.) The codebook has as many rows as the dataset has columns (variables, fields). The columns (fields) of the codebook may include: ? variable name ? type (character, factor, integer, etc) ? variable label

...e statistics * combining this information with metadata (such as item labels and labelled values) derived from attributes To do so, the package relies on 'rmarkdown' partials, so you can generate HTML, PDF, and Word documents, and embed the codebook in a larger document providing context. Codebooks are also generated as tables (CSV, Excel, etc.) and are invisibly embedded as JSON-LD in generated HTML files. JSON-LD for datasets is not yet supported by search engines, but hopefully will be. Critiques, bug reports and enhancement requests are welcome as GitHub issues. I'm a social scientis...

...e statistics * combining this information with metadata (such as item labels and labelled values) derived from attributes To do so, the package relies on 'rmarkdown' partials, so you can generate HTML, PDF, and Word documents, and embed the codebook in a larger document providing context. Codebooks are also generated as tables (CSV, Excel, etc.) and are invisibly embedded as JSON-LD in generated HTML files. JSON-LD for datasets is not yet supported by search engines, but hopefully will be. Critiques, bug reports and enhancement requests are welcome as GitHub issues. I'm a social scientis...

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 and th...

The codebase sets up ogg_int32_t, etc, but then uses long directly in several structures. Unfortunately for me longs are 64 bits on my platform, not 32, and I end up getting hammered by unnecessary software math routine calls. Should I be able to just search/replace 'long' with 'ogg_int32_t' in the code or would that cause more problems than it fixes? -Dave --- >8 ---- List

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, Vorbis uses codebooks, for example to do vectorquantization and huffman-encoding. My question is - are all these codebook dynamicly generated ("trained") or are there also static codebooks used ? If yes, what specific tasks are these 2 types used for, during encoding ? Thanks Stoffke <p>--- &g...

I'm having trouble decoding the number of codebooks out of an ogg file, and was wondering if anyone here could lend a hand? I read in the sync pattern, and I think the codebook dimensions properly, but when I try and read in the number of codebook entries, I get a number larger than the number of bytes in the file, which I have to assume is wrong :...

...a brick shit-house, asserts all over the place because I'm paranoid that I'll forget something subtle during any early-stage code production. Lots of XXX paranoia comments still to verify/clean up too. Edit rtvorb.h to enable debug code Soon to be added: link with libcurl to get .sdp or codebooks via http. Right now it just attemps fopen. (at some point, probably build in a 'standard' set of codebooks into the player, so normal folks don't have to have the decoder do anything special to retrieve codebooks. Codebook packets are checked by md5 sum) http://vorbis.on2.com/libvo...

...ying to write a Vorbis decoder (just as a hobby) but I've got a problem with reading the setup header. According to the Vorbis documentation the first data that should be read after the initial 'vorbis' string is an eight bit integer which when incremented by one, contains the number of codebooks in the header. My problem is that whenever I read this number it seems to be wrong! For example, I created a very small Ogg Vorbis file and in this file the first byte of the setup header is 29 (hex). This means that 42 (dec) codebooks should follow. However this is not the case - in the entire fil...