similar to: DCT in Theora

Why for white-pixel image, oc_enc_fdct8x8_c() returns the matrix with non-zero AC-coefficients? _x[64]: * 107 107 107 107 107 107 107 107 * 107 107 107 107 107 107 107 107 * 107 107 107 107 107 107 107 107 * 107 107 107 107 107 107 107 107 * 107 107 107 107 107 107 107 107 * 107 107 107 107 107 107 107 107 * 107 107 107 107 107 107 107 107 * 107 107 107 107 107 107 107 107 _y[64]: * 3426

Hi. I am trying to find calls of idct/fdct.c functions by tracing png2theora.c calls. But found only: analyze.c:oc_dct_cost2() Where and when idct/fdct/mmxidct/mmxfdct.c functions are used? Mentions of "dct" word: ==== pacify at optima-amd64:/usr/src/libtheora-1.2.0alpha1/lib$ grep dct *.c | cut -f1 -d":" | uniq -c ???? 19 analyze.c ???? 28 decode.c ???? 22 encode.c ????? 4

Hello, Here is my first speedup patch. Like 10-11%. No IDCT yet. Please feel free to comment my code or even better think about improvements. :) I belive my routines are not so bad, maybe one day they will be even more faster. What needs to be optimized is the loop filter fuction. I have no ideas now how to do it. It does not leave much space for parallel stuff, copying memory from lot of

Why in the procedure oc_enc_block_transform_quantize() is used function oc_idct8x8()? After all, Inverse DCT only need to decoding stage, rather than coding?

Hi, Attached is the first version of the DCT callback. It's still a bit WIP, but now you have something to refer to when I'm rambling :) Best Regards, Thorvald -------------- next part --------------

Looking for the DCT function, but don't see it in the signal pkg. http://rss.acs.unt.edu/Rdoc/library/signal/html/signal.package.html http://rss.acs.unt.edu/Rdoc/library/signal/html/00Index.html As I understand it, the 'signal' functions are ports of the corresponding matlab/octave code, where the DCT exists. Did I miss it (different name?) or is someone working on a port for

Good day! I'm creating HDL IP CORE (for using in FPGA) for theora encoder (now only I-frames). I don't undestand one moment. Now i develop such stages: 1. From RBG(byer) to YCbCr converter 2. DCT processing (8x8 pixels blocks) 3. Quantizator of DCT coeff. 4. Zig-Zag of quantized DCT coeff. and now i have uresolved last stage of compression - how i must send 8x8 blocks to huffman

Hi. I have been working on a tool whose goal is to reduce the bit rate of theora video by decoding to DCT coefficients, reducing the entropy of the coefficients, and re-tokenizing the stream. I have successfully used the decoder source to extract the DCT coefficients for each block, and I am able to capture any and all relevant information about where the block of coefficients falls in the

Dear all, I was wondering whether anyone knows about a program which converts (part of) a data definition file (such as a .dct file for stata, or .sas file for sas) into an R-script. Here is an example with a .sas file: <-- snipp VALUE HTYPE (default=32) 0 = "Not in household" 1 = "Married couple family household" 2 =

Hello, Here is my first speedup patch. Like 10-11%. No IDCT yet. Please feel free to comment my code or even better think about improvements. :) I belive my routines are not so bad, maybe one day they will be even more faster. What needs to be optimized is the loop filter fuction. I have no ideas now how to do it. It does not leave much space for parallel stuff, copying memory from lot of

Hello, I would like to announce the semi-optimized oc_state_loop_filter_frag_rows It gains like 7% speedup. Unfortunately it has some issues: 1) wont compile on 64bit (I will fix it later hopefully) 2) is not yet fully optimized (instruction stalls) Here are the results. CPU: Athlon, speed 1466.91 MHz (estimated) Counted CPU_CLK_UNHALTED events (Cycles outside of halt state) with a unit mask

Hello, I'm attaching IDCT MMX patch. I reused IDCT from theora-a3-MMXd.zip. It should work on 64bit X86 platform too. Here is most used functions when playing video with jet aircrafts (gripen) Ogg logical stream 310b2968 is Theora 720x480 29.97 fps video Encoded frame content is 720x480 with 0x0 offset I can play this video with like 200-300 frame drops on Athlon XP 1700+ CPU load (with

Hello, As we discussed with derf some time ago, it seems it is not neccessary to enforce "forward" order of dct_coeffs. This patch gains .99366902855226196000% so approx 1% speedup. Meausurement method: time nice -n -19 ./dump /mnt/disc4/theora/unix/gripen.ogg > /dev/null Ogg logical stream 310b2968 is Theora 720x480 29.97 fps video Encoded frame content is 720x480 with 0x0 offset

This probably qualifies as bikeshedding, but how strict are the style norms for TableGen? Some aspects of it, like individually and consecutively declaring all *_ENC variables in this manner: class ADDU_QB_ENC : ADDU_QB_FMT<0b00000>; To be used only once, in this manner: def ADDU_QB : ADDU_QB_ENC, ADDU_QB_DESC; Seem like avoidable clutter to me. The files tend to be pretty big,

Hi, I am very new to Theora, having just started working through the code a few weeks ago. I am working on a requantization tool to reduce bit rates, hopefully on the fly, for some video conferencing work. As I was working through the encoding phase I noticed this line in encode.c: for(ti=_enc->dct_token_offs[pli][zzi];ti<ndct_tokens;ti++){ It's around line 804, but I am

Hi, I'm new to Theora and would like to propose several performance optimization using advanced instructions in x86 CPUs (SSE2-SSE4.2). There are several source files in \x86 and \x86_vc which developed using inline assembler. However this cause several maintenance problems: 1) Need to sync gcc & msvc versions 2) Only 32bit environment is supported 3) No support for newer than MMX