Displaying 20 results from an estimated 400 matches similar to: "Theora decode problem"
2006 Oct 06
0
V4L + Theora small app...
Hi all.
I post a small app I made that create 2 clips using a V4L device.
I would like to get every tips you think it's useful...
Some notes:
- I make 2 clips because in our project we create series of clips and
it's important to check that the all the resources ( memory,
descriptors, etc. ) are freed correctly and to reuse all the resources
that can be reused
- the clips are not well
2004 Nov 20
0
ffmpeg2theora start and end time support
For last few days I was trying to learn ffmpeg and libtheora API. In the
process, I have modified ffmpeg2theora code to include support for start
time and end time.
ffmpeg2theora -s 60 -e 130 file.avi
will produce file.ogg which will be from 60th to 130th second of input
file (something like -ss and -endpos in mencoder). This is a useful
feature for someone who wants to cut a part of video
2005 Oct 05
1
Simple encodig sample...
Hi all.
I'm Mat & I'm new :)
I'm testing libtheora + libogg perhaps for a commercial product.
I started watching encoder_example.c ... I simplified it for testing
it easier.
It seems ok to me but I have no experience with theora so I would like
to know if my code is correct.
I tried to debug it with Valgrind and I found 4 possible memory leaks...
but I think they can be
2005 Feb 09
1
Trying to do windows encoding dll
Hi everybody, me again.
I'm trying to write my own VFW-like dll... It doesn't need to do much.
1.) compress a single frame and give it back to the host application
2.) host applications sends the frame
3.) client application receives frame
4.) client application tells the dll to decompress the data
So if I try to do this, something is going wrong...
Perhaps someone could have a look at my
2005 Nov 03
1
CPU usage while encoding...
Hi all.
In my test application I saw that the encoding process with Theora is
too CPU expensive ( compared to FFmpeg - MP4 ) ...
Perhaps I'm using wrong parameters:
ti.fps_numerator = fps * 11 + 1; // var framerate
ti.fps_denominator = 11;
ti.aspect_numerator = 1;
ti.aspect_denominator = 1;
ti.colorspace = OC_CS_ITU_REC_470BG; //
2005 Sep 07
1
encoder settings
Hi!
Some background: I am trying to create an application that would
encode video taken by USB camera using Theora and then send it
to the client. I have almost succeeded, but I have one problem.
When I grab video frames from the camera and encode them they
form 4KB OGG pages, then I send them over TCP/IP to the client
application. Since I want to achieve as small latency as possible I
2010 Jun 14
4
Live Stream Encoding
Hi There,
i want to stream some pictures out of my application using the Theora
codec. I can stream to a socket or a file. The current work based on the
png2theora example. Something while enconding went wrong: I can see the
whole video in VLC, but the complete duration of the file will not be
displayed. If i play the video in Firefox, the first 2 seconds will not
be played. I think the
2004 May 20
0
theora header bitmap for alpha3
below is an rfc-style bitmap of the initial theora header. I've checked
it against the spec and the code in libtheora; please double check :)
I'm posting it here for those implementing demux stages (which necessarily
don't use libtheora), and hence offering it for the spec. A typical
demux stage just needs to pick out the FRN, FRD and KFGSHIFT fields,
without going through the whole
2009 Jul 08
2
Theora 1.1 rate controller
Hello everyone,
I'm currently developing an adaptive videoconferencing application based on
Ekiga which uses TFRC as a congestion control mechanism to adapt the video
encoding rate according to the quality of the network experienced. My goal
was to use the open-source Theora codec for video transmission.
Unfortunately, it seemed that Theora 1.0 did not properly implement any
correct CBR mode.
2006 Oct 04
3
Encoding - CPU usage ...
Hi all.
I would really like to use Theora for the commercial product I work on...
It's a Linux based DVR. Actually we use ffmpeg to produce MPeg4 short
clips from 4 BNC channels in CIF resolution.
I made a small module for our project that uses Theora... but I see that
it gets a lot of CPU :(
So I'm here to ask for any kind tips to reduce the CPU usage.
- Hardware... do you think there
2009 Jul 07
1
Estimate bytes per second from th_info-settings
Hi
Is there a way to estimate the number of bytes per second from the information passed in the th_info-struct to the Theora encoder's th_encode_alloc()? I'm trying to be able to give users a rough estimate of the file size needed to encode with the setting provided to th_info-struct (frame width/height, fps_numerator/fps_denominator, target_bitrate and quality).
-- Bjoern
2004 Apr 01
1
Theora MVect not defined in coding mode 0
Just wondering if someone can help me out...
I'm testing the core of my decoder filter (win32)... and when i get into this function:
tatic void DecodeMVectors ( PB_INSTANCE *pbi,ogg_uint32_t SBRows,ogg_uint32_t SBCols )
The decoding mode is 0.
When it attempts to do these lines....
pbi->FragMVect[FragIndex + 1].x = MVect[1].x;pbi->FragMVect[FragIndex + 1].y = MVect[1].y;
2006 Aug 06
0
Newbie: How to rewind a videostream (long)
Hello, I'm new to this list, and pretty much also to the codec universe.
In a computer game I'm working on, there is an 3D TV-screen onto which I
project the frames of a movie. The movie is of course stored as theora, no
audio as it's not needed yet. I have it working so far, extracting a frame
and uploading it to the graphics card when the scene is drawn. The example
file
2010 Mar 25
2
Questions about encoder parameters.
I have almost finished integration of Theora into our videoconferencing
program. Since a videoconferencing program is realtime, it is UDP-based
and wraps the Theora stream in RTP (More on that later). The problem
here is that most examples I could find, wraps the theora stream in ogg,
and used over tcp or files. I send over UDP and clients need to be able
to start in the middle of the stream.
2004 Sep 15
1
Theora mcomp tuning...
Hi there.
This patch changes the block selection to quantify error
based on the sum of the squared differences of the pixel
values rather than the sum of the absolute differences,
the former conventionally and statistically seeming like
the preferable thing to do.
The patch also const'ifies some parameters (which doesn't
affect code quality on recent GCCs but might help on older/
other
2004 Dec 19
0
[patch] more ffmpeg2theora improvements
Hi,
the attached patch (against current SVN) adds three new options to
ffmpeg2theora: --keyint (set keyframe interval) --smoothness (set the
theora_info::sharpness encoding parameter) and --noautosync (disable the
new frame dropping/duplicating code).
It also fixes a bug with the processing of --cropright that sometimes
segfaulted. The sync adjustment code is now tuned to be more reliable.
BTW
2004 Jul 26
1
theora_info struct question
Hi
I'm evaluating Theora for a video communication system and would like some
info as to what the following struct members (from the theora_info structure)
do and what values one should pass to them:
If there is some documentation somewhere that I've missed, please direct me to
it.
===== Extract from theora.h =====
int quality;
int quick_p; /* quick encode/decode */
2007 Jan 23
0
Bitrate expectations for encoding or decoding
Hey Folks.
I'm currently working on implementing Theora Video playback for the
Unity engine (http://www.unity3d.com). So far everything works fine,
But I have a small question:
Is there a reliable way to predict what bitrate a stream will have
when encoding or decoding?
Of course, there's the target_bitrate parameter in the Theora Info
structure, but somehow, I always get quite
2008 Nov 04
1
[PATCH] liboggz: Update Dirac granulepos definition
The definition of granule position for an OggDirac elementary stream
isn't the same as theora.
Index: tools/oggz_tools.c
===================================================================
--- tools/oggz_tools.c (revision 3759)
+++ tools/oggz_tools.c (working copy)
@@ -454,7 +454,15 @@
iframe = granulepos >> granuleshift;
pframe = granulepos - (iframe << granuleshift);
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;