Displaying 20 results from an estimated 10000 matches similar to: "question about ogg mapping"
2003 May 24
5
Win32 experimental player/encoder
it appears your encoder/player do not yet reflece the changes rillian introduced wrt theora headers, which have been split into three parts -- header proper, comment, and tables (see toplevel.c).
It's strange that your code works at all linked against the new libs; presumably since the tables still have the hard-coded values, if you encode & decode from the same lib compile you won't
2002 Oct 29
3
Simple player and encoder binaries for Windows
--- Stephane wrote:
VP3 codec uses a lot of CPU for decoding. We will need some optimization
because now this codec is way too slow for home uses.
--- end of quote ---
Actually, the Windows VP3 QuickTime codec runs just fine on a 400MHz Pentium II box, with only occasional glitches on some dodgy Celeron systems. At work, we routinely test 320x240 full-color, full-motion video on low-end boxes.
2002 Sep 16
2
AW: Keyframe seeking in Ogg and spec
Hi all,
> One problem I see with your proposed implementation is that it does
not
> specify how audio and video would be synchronized, since there are no
> absolute time stamps for the video frames. So it is difficult to
account
> for
> audio latency on different systems, much like when you play an AVI
file.
> Ideally it would be wonderful to have timestamps that could be used
2002 Sep 13
6
Keyframe seeking in Ogg and spec
Folks have noticed that the documentation is semi-silent about how to
properly encode the granule position and interleave synchronization of
keyframe-based video. The primary reasons for this:
a) we at Xiph hadn't had to do it yet
b) there are several easy possibilities, and the longer we had to
think about it before mandating One True Spec, the better that spec
would likely be.
The
2002 Sep 16
2
Can't find the setup code
Well, I've been slamming my head against this all night, so it's time
to ask for help...
Having gotten together a reasonably decent port of what I thought was
the whole API to the Ogg Way, complete with Ogg mem management and
bitpacking, I started digging deeper in the code... only to find that
it looks like I only have a middle stream handler. The encode and decode
code both assume that
2003 Mar 18
6
bitstream changes
ok now I see why we need another packet in the header. The first one is basically for ID purposes (theora_decode_header()). I've jammed my huffman trees in there but it sucks because I need them later on when I actually build the huffman tree structs (theora_decode_init, calls InitHuffmanSet()). At that point the original header packet is gone so I've been keeping it around in a buffer.
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
2008 Nov 11
5
further debugging of my ogg/theora decoder
Hi,
I am continuing to try to debug my ogg/theora decoder.
The issue seems to be that not enough packets are being pulled from the
bitstream, here is some sample output from my player with some debugging
comments put in:
(playback began at first frame, this is from the middle of the clip)
get page at 1765027
got packet
frame++, skip is 0
frame decoded
page processed, kframe=414 : offs=442
get
2002 Oct 18
3
Quicktime Vs Windows encoding with VP3
I found out about vp3 from the new winamp and coincidentally i also happen to be trying to find a suitable solution to broadband streaming.
I have used flaskmpeg to create a 17mb .avi file from an 82mb Mpeg 1 file and it looks great it took about twenty minutes to encode. It runs for eight minutes and the audio is also fantastic using the lame encoder.
However when I try to do the same in
2002 Jul 17
1
Introduction, questions
First, an introduction: I work in a group that makes educational software. In the coming months, we're planning to release our entire Mac/Windows runtime under the GPL. We currently encode our audio with MP3 and our video with VP3. For playback, we rely on QuickTime 5 on MacOS and Windows.
In the short run, we'd like to help maintain the VP3 QuickTime codecs, preferably without
2006 Apr 04
2
ogg + theora + seeking
Hi all,
I'm actually learning how to use ogg, theora and vorbis. My idea is to create
a small program running, that is able to concatenate ogg video+audio files.
However I have some small questions. Here I will start with the first one:
I read the following for seeking in ogg for a theora key-frame:
---- snipp (http://www.xiph.org/ogg/doc/ogg-multiplex.html) ----
[...]The third point
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 Jul 07
2
Legalese. What is stride?
Hello all.
I've been playing around with theora since it first entered CVS, and I
like what I'm seeing. Today I've been fixing xine's theoraplugin to
understand theora_info.frame_{width,height} and
theora_info.offset_{x,y}. I only got it working after some experimenting
and basically copying the code from player_example. A few questions
related to this:
1. What are the legal
2002 Oct 22
1
compglobals.c
pls let me know if/when you have theora compiling & running on Windows.
-----Original Message-----
From: Tabuleiro [mailto:beta@tabuleiro.com]
Sent: Tue 10/22/2002 3:13 PM
To: theora-dev@xiph.org
Cc:
Subject: [theora-dev] compglobals.c
I believe this file is no longer used and contains functions that are no
2008 Aug 12
7
New Ogg Dirac mapping draft
David Flynn has proposed a new Ogg Dirac mapping. The draft is here:
http://davidf.woaf.net/dirac-mapping-ogg.pdf
This is a much bigger break from other codecs than my draft (at
http://wiki.xiph.org/index.php/OggDirac). We talked a bit about it on
IRC today. Below is my summary; hopefully David can correct anything
I got wrong or misleading. Comments?
There are two main differences
2008 Feb 07
2
Seeking to granules in discontinuous streams
> No particular answers, but I can at least point out that the way
> things were designed for CMML was to work with the existing Ogg
> seeking algorithm. The idea is that a generic seeking routine can work
> on any Ogg file, as long as it knows the granulepos->time mapping for
> the logical bitstreams in the file. That's why all the
> timestamp-related info is crammed into
2010 Jun 04
2
OGGZ Seeking in Theora
Dear all
I'm aware that there have been several discussions about the seeking
issue and I'm sorry to bring this up again.
To solve the problem with Inter-Frame garbage, a seek to the previous
keyframe has to be made. The keyframe number should be extracted from
the granulepos of the frame where we want to seek to. I hope I
understood the theory - unfortunately a few questions have
2008 Feb 12
2
Seeking to granules in discontinuous streams
Ups! Maybe it's time somebody corrected that statement then - the wiki seems
the right place to put the correct algorithm, IMHO.
Cheers,
Silvia.
On Feb 13, 2008 10:06 AM, Ralph Giles <ralph.giles@artifex.com> wrote:
>
> On 12-Feb-08, at 2:57 PM, Ralph Giles wrote:
>
>
> http://wiki.xiph.org/index.php/GranulePosAndSeeking
>
> I'm not sure it's helpful to
2010 Mar 11
4
Seek issue in cortado player
One of the issues I've consistently run into with the cortado player app is seek behavior, so I was curious to see how cortado handles video encoded with the latest ffmpeg2theora (0.26) and the new -seek-index option, so I tried converting an h.264 video:
ffmpeg2theora tronlegacy-tsr1_480p.mov --seek-index
This output the following advisory messages:
> Allocated 372 bytes for theora
2008 Feb 01
6
Dynamic Change Parameters..
I am going to improve theora codec with dynamically changing way. In this
case we want to change compression parameters like video_q, sharpness when a
keyframe is generated. When i set video quality parameter using cpi->
pb.info.quality in CommpressKeyFrame in encoder_toplevel it will not change
dynamically. Can you please help me to do this. Wich function should i cange
to achieve my