similar to: resolution issues

Displaying 20 results from an estimated 8000 matches similar to: "resolution issues"

2003 Mar 05
5
VP3 IDCT
Hi, Is there anything special I need to know about VP3's IDCT? I mean besides the fact that there are separate IDCTs to handle sparse coefficient matrices. Are the IDCT functions mathematically equivalent to any textbook IDCT functions? Thanks... -- -Mike Melanson --- >8 ---- List archives: http://www.xiph.org/archives/ Ogg project homepage: http://www.xiph.org/ogg/ To
2003 Mar 09
4
Proof of Concept
Hi, So it took a little while to get here but VP3 through ffmpeg is finally starting to achieve viewable results. It partially works right now. Keyframes only. And monochrome. Oh, and the picture is upside down (something I did not realize about VP3 until I let it fly just now). Anyway, here is a picture of ffmpeg's VP3 decoder in action using xine:
2003 Dec 06
5
What sort of math i required?
Hi, Keep up the good work! The file sizes of Theora's output is amazing! I have just joined the list, and would like to contribute to the
2007 Jan 06
7
FFmpeg Theora encoding patch
Hi, Attached is my patch to add theora encoding to ffmpeg's libavcodec (by using libtheora). I am requesting help to fix the bug I mention below and am seeking general comments before I submit the patch properly. Files encoded using this encoder have a problem playing in VLC. The files will not play unless "Drop late frames" has been unticked in the advanced video settings.
2004 Mar 02
1
VP3 Format Doc, v0.4
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:
2003 Feb 26
7
[OT] Just saying hi!
I hope this list is small enough for not beeing banned when introducing oneself. So... Hi, I just subscribed to the theora-lists. I'm from the XVID project, so I know a deal about video and MPEG-4 in particular, but nothing about Vorbis/Theora etc., That's why I'm here, because I'm interested in patent-free alternatives. I guess there is no documentation of the current status
2011 Mar 31
1
DCT-coefficients in
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
2011 Mar 22
5
FPGA encode stages flow diagram
Good day! I create diagram of encoder process. Using it i create implementation of encoder in FPGA (Xilinx/Altera). Please critique it. Is there missing stages? Here is blog http://developer-fpga.blogspot.com/ Here is picture of encoding stage 1 https://lh4.googleusercontent.com/-NV8o9DG3jvE/TYjYXr-dYGI/AAAAAAAAAos/U06O-YvhSI0/s1600/stage1.jpg Here is picture of encoding stage 2
2005 Feb 11
1
Changing the IDCT spec
So, in preparation for some decoder optimization work planned by Rudolf Marek, the subject of the size of the registers needed in the IDCT came up. The current spec language ensures that the result is exactly compatible with the C code for VP3. This language requires that some of the arguments to the multiplies be 17 or 18 bits, because they need to hold the sum or difference of two 16-bit
2003 May 28
2
autoconf problem
./configure: line 524: syntax error near unexpected token `AM_INIT_AUTOMAKE(libtheora,0.0)' ./configure: line 524: `AM_INIT_AUTOMAKE(libtheora,0.0)' I'm sure I'm doing something pro-stupid, but --- my setup works fine for ogg & vorbis. autoconf ver 2.13 automake (GNU automake) 1.4-p4 if that matters hey let's put tool version numbers into the README -dan
2002 Nov 11
3
Theora vs. Nullsoft NSV
How does the Theora project differ from Nullsofts NSV project? Other than the obvious fact they use mp3.... <p><p>--- >8 ---- List archives: http://www.xiph.org/archives/ Ogg project homepage: http://www.xiph.org/ogg/ To unsubscribe from this list, send a message to 'theora-request@xiph.org' containing only the word 'unsubscribe' in the body. No subject is
2010 May 04
2
Why Our Civilization's Video Art and Culture is Threatened by the MPEG-LA
http://www.osnews. com/story/ 23236/Why_ Our_Civilization _s_Video_ Art_and_Culture_ is_Threatened_ by_the_MPEG- LA it looking more and more like GIF/LZW/Unisys, but it called Microsoft/apple/ MPEG-LA/etc and I cant wait until there is a video camera that is not using codec from MPEG-LA
2002 Aug 05
3
Cross-Compiling VP3 lib on Linux
Hi, I have been working with VP3 for some time now. Dan Miller from On2 just told me about this list. A few months ago, I managed to get On2's VP3 source snapshot to compile under Linux, a feat that many have apparently attempted and quickly abandoned. I compiled a small console app and the results of the experiment are explained here:
2002 Aug 28
5
Analogue artifact estimation
Hi List, Just batting a few ideas around here, but would it be possible to include in to the codec, estimation for common video artifacts that occur in the analogue world? For example, anything that's gone through a composite stage will likely have dot-crawl and false colour - if we can recognise this effect in the encoder, we can treat it as a special case. Other artifacts that come to
2003 Jun 14
6
dead DCSearchPoints code
Dan, In reviewing the code, derf came across the DCSearchPoints array in QuadCodeDisplayFragments(), encode.c:696. It looks like it specifies a search order for nearby coded fragments for prediction if there isn't a nearest neighbor. However, the upper search bound is defined as *0*, so the search loop (line 917) is never executed and it always falls back to the last coded fragment.
2011 Mar 18
3
alghorithm of working encoder in libtheora
Hi, Is somewhere alghorithm description of encoder process implemented in libtheora? May be some drafts? May be frame dataflow throw encoder stages? PLEASE -------------- next part -------------- An HTML attachment was scrubbed... URL: http://lists.xiph.org/pipermail/theora/attachments/20110318/c3e8e109/attachment.htm
2003 Feb 23
6
More Missing Pieces
Hi, I am making good progress on understanding, documenting, and re-implementing VP3. I have found some more deadwood in the decoder code and I just wanted to verify that it really has no place: * Version 3.3 tables: There are 2 sets of VLCs: One for v3.1 and one for v3.3. The v3.1 set is always selected. Are the v3.3 tables in production, or will they ever be? * DC Search Points: VP3
2004 Jul 02
4
Encoding paramaters...
I've got my encoder working now... and i put a proeprty page interface to allow the user to set a few encoding paramters to start off with... but changing the paramters doesn't seem to make barely any difference... These are the defaults i'm using... mTheoraInfo.target_bitrate=400000; mTheoraInfo.quality=30; mTheoraInfo.dropframes_p=0; mTheoraInfo.quick_p=1;
2003 Oct 09
4
Updated VP3 Document
Hi, I have been on a documentation kick recently. I finally updated my VP3 format document tonight: http://www.pcisys.net/~melanson/codecs/vp3-format.txt v0.2: October 9, 2003 - expanded section "Reversing the DC Prediction" - added Appendix B: Theora Differences Feel free to look it over and point out any glaring mistakes. I can't wait to see how much sense it makes to
2002 Aug 06
1
VP3 Patch For xine
Hi, Since a number of people are eager to try out the native VP3 decoder in xine, I have made a patch available, bz2-compressed: http://www.pcisys.net/~melanson/codecs/xine-vp3-decoder-patch.bz2 To work with this patch: 1) Get the latest xine-lib from CVS. Visit this page for more details: http://sourceforge.net/cvs/?group_id=9655 The module name is xine-lib, but you will also need