search for: granpos

Displaying 20 results from an estimated 24 matches for "granpos".

2010 Apr 23
2
Ogg Index A-mod
...a prefix > code, so no additional delimeters are needed to separate values. Am I right to assume that the binary value of the remainder is encoded in a fixed width field of log2(Golomb_Rice_parameter)? e.g. log2(16)=4 bits in this example? > Note that it is not always safe to > round granpos down after division: if rounding down would cause the > granpos > to move too early, then it must be rounded up. Can you give an example of this? Is it the case when you divide the granulepos such that it moves to before the previous keypoint's granulepos? > 9. 'n' key poi...
2009 Jun 05
2
Ogg Skeleton
Hi, I got a short question regarding the ogg skeleton. As far as I understand it, the skeleton information helps to decode the timeing from the granule position, that is available in every ogg page, so that I can say, what is the end time of the last full ogg packet within an ogg page. So but it does not help me finding out the timing information about the other packets in between? -Yorn
2004 Feb 16
1
Ogg mux design
Monty, Thanks for writing up your thoughts on the mux design (ogg/doc/ogg-multiplex.html in cvs) Now that there's something to argue with, I'd like to comment. To recap, the documented proposal is that we make two categories of streams within the OggFile multiplexing library. Pages are sorted chronologically by the timestamp equivalent of their granulepos fields. Normal data like
2010 Jun 01
3
Fwd: Skeleton 4.0 draft, help with Dirac fields please!
...to include extra granulepos > fields to Skeleton 4. Given the underwhelming discussion regarding this, > I'm guessing the need and/or desire for these fields isn't really there. I haven't commented mostly because I don't know what Monty's plans for a "grand unified granpos scheme" are. All of this is mostly in his head right now, and he needs to be the one to provide feedback.
2010 May 11
4
Fwd: Skeleton 4.0 draft, help with Dirac fields please!
On 10 May 2010 23:20, Chris Pearce <chris at pearce.org.nz> wrote: > The granulepos radix was something that Conrad and Ralph were talking about > at FOMS2010. I don't know how it's supposed to be used, or why we need it. > It was supposed to be needed for Dirac? Maybe Ralph or Conrad can remember? > If not, we should remove it. There's no point in adding a poorly
2008 Feb 28
2
Re: Updating the Ogg mapping for Dirac
...ly out of le32 > > fields in the bos page, there would be less room for error. > > How is this better than reading he same info out of a fishbone packet? The 'shim' paradigm does not use fishbone. The Ogg spec currently needs information necessary to interpret granulepos and granpos indexing in the initial header... Monty
2009 Jun 05
2
Ogg Skeleton
...2009 at 4:30 AM, ogg.k.ogg.k at googlemail.com <ogg.k.ogg.k at googlemail.com> wrote: > It holds the granulerate, so it'd allow this for those codecs that use the > granule shift way of encoding their granules (except for those pages > where no packet ends, as these will have no granpos set). BTW, we need to add another field out of the remaining reserved bits to accommodate reordering codecs like dirac. -r
2009 Feb 05
2
Pages with granulepos = -1 while encoding..
Hi all ! Following my recent issued with my encoder, I've narrowed the issue to the fact that, when encoding, for some returned pages, the granulepos returned by the libogg is -1. Is that normal ? How should I intepret it if I want to order the pages ? Romain
2009 Feb 16
2
Theora packets with granulepos of -1
Hello, I'm just totally confused. In my theora streams encoded using ffmpeg2theora (but also when using my own encoder) I have packets with a granulepos of -1 so I can't identify the packet during a seeking operation correctly. I can also see those strange value when I just print the packet granulepos before sending it to the Theora decoder. I know why there are PAGES with granularpos of
2008 Aug 15
0
Fwd: Fwd: New Ogg Dirac mapping draft
On Wed, Aug 13, 2008 at 3:05 AM, ogg.k.ogg.k at googlemail.com wrote: > And that's the canonical way AFAIK. Comparing times computed from > the granpos you get from pages you get from a bsearch requires good > knowledge of the codec, whereas comparing granpos can seek within > any codec. No. it's in general impossible to calculate the granulepos that corresponds to a particular time in a theora stream; only the reverse is possible. That...
2004 Jun 18
5
Patch to stop vcut from generating broken streams
Skipped content of type multipart/mixed-------------- next part -------------- A non-text attachment was scrubbed... Name: not available Type: application/pgp-signature Size: 189 bytes Desc: Digital signature Url : http://westfish.xiph.org/pipermail/vorbis-dev/attachments/20040618/e7bee431/attachment.pgp
2008 Feb 22
2
Seeking to granules in discontinuous streams
Hi, do you still think you need all this, if you are allowed to have equal granulepos on subsequent pages? Conrad. On 18/02/2008, ogg.k.ogg.k@googlemail.com <ogg.k.ogg.k@googlemail.com> wrote: > Hi, > > I've now got another way of encoding granule (oh, not *again*, I hear > you cry). I believe it's an improvement over the existing "generic" > method, so
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 19
4
non-decreasing granulepos
Hi all, something which came up recently in relation to the design of Kate's granulepos was whether or not the granulepos of successive Ogg pages is allowed to be the same, ie. whether or not granulepos must be strictly increasing. As this question is more generally about Ogg granulepos, how about we answer it first and then get back to the discussion of Kate's granulepos ... Here is
2008 Apr 11
1
Ogg/Spots and Ogg/MNG
...ugh paletted ones only are supported, as I originally intended to let more complex images, if some were needed, to a separate Ogg/MNG or Ogg/Spots stream). Category set to "album-art" or something. Then add each still image. There still is a question of what to do with the timing. Set the granpos to zero, and rely on the client code to interpret a category of "album-art" to be "timeless" is the obvious idea that comes to mind. Hmm, a bit too hardcoded though. Maybe setting granulerate to zero. Hmm, no, that'd cause a lot of divides by zero would it. MNG does look co...
2008 Mar 18
2
Determining the duration of an ogg vorbis file
Hi all, I've got a question on regarding how to find out the duration of an ogg vorbis file. Sorry if it should already be mentioned somewhere in the docs, but I couldn't find out how to do it the best way. So, I can read the [bitrate_nominal] field from the identification header (if it is set), find out the size of the audio data (by subtracting the size of the three headers from the
2008 Mar 21
0
AW: Determining the duration of an ogg vorbis file
...vorbis stream should tell > you the duration in samples, divide it by the samplerate to get the > duration in seconds. ...that tells you the end time. In the event that the beginning time is at a positive offset (like in a typical live stream) you also need to subtract the starting time (granpos on the first audio page) Monty Lesen Sie Ihre E-Mails auf dem Handy. www.yahoo.de/go
2009 Apr 08
1
How can I get the precise play time of the ogg vorbis file?
Hi all, ? I have a?question about the ogg vorbis decoder.?As far as I know, there are?three?vorbis headers -- ID, Comment and Codebook. And in?ID header, I can get the sample rate, maximum bitrate, nominal bitrate and minimum bitrate. Now, I want to get the play time of the file, so I use the file length to divide the nominal bitrate, and get the play time, but it is always shorter than the real
2010 Jun 01
2
Fwd: Skeleton 4.0 draft, help with Dirac fields please!
...fields to Skeleton 4. Given the underwhelming discussion regarding this, >>> I'm guessing the need and/or desire for these fields isn't really there. >> >> I haven't commented mostly because I don't know what Monty's plans for a >> "grand unified granpos scheme" are. All of this is mostly in his head >> right now, and he needs to be the one to provide feedback. > > I've been trying to write it down such that it is clear or not if I > understand everything I need to (especially in the case of dirac). ?Up > to this point I...
2009 Aug 24
2
oggz reading & seeking
??????? I've rewritten my theora player using liboggz. I've stumbled upon a few issues though. First of all liboggz exposes oggz_read and oggz_run, but how can i read only sound data, or only video data using liboggz, say something like this: oggz_read_sound(1024), oggz_read_video(1024). ? ? ? ?? Second of all i tried using liboggz's seek function. Immediately after the seek i get some