[theora-dev] Suggestions and questions
philipj at telia.com
Wed Oct 2 11:48:59 PDT 2002
I'm not a developer but it takes one to answer my questions. I was just
thinking about how the command line encoder could work in the end (after
having played with encoder_example)
1. There could be the option of having a -q switch (just like oggenc)
controlling BOTH audio and video so that for each level of q the sum of
video and audio bitrates could be known (sort of like the nominal in
Vorbis). In this case there should also be some switch controlling how
much to prioritize audio and video respectively (for example: 0=top
audio priority, 1=equal, 2=top video priority). The point would be the
ease of predicting file size and perhaps more important the ease of
matching corresponding video and audio qualities.
2. Instead of this buisness of predicting file size, could there be an
option where you first deside file size? Is it possible to scan the
video and audio and to somehow register an "ease of compression" value
for bunches of audio samples and video frames? If yes, then these values
could then be used to determine exactly how many bits allowed for audio
and video while matching file size and still not using the same bitrate
for the entire file. (a 0-1-2 audio-video control like in previous
question should apply to this too).
3. Would it be possible to work into the theora framework the
possibility that a portion of a video file could be played from an
external file? Example: I want my Star Trek TNG episodes from DVD to
drive. The opening and titles are the same in each episode (almost) and
therefore I want to save space by forking them in like I said. Is this
possibly not the job of theora but rather some higher level mechanism,
or am I just being stupid? Perhaps something like those strange text
files that hide in front of wmv streams are what should do this, sort of
a playlist only one clip is forked into another. If the ogg had 2
logical streams there wouldn't be a problem putting something in
between, would there?
4. Could there a standard "aspect ratio" (like DVDs and mpegs have) tag
in the ogg file that would allow for any future players to prescale the
video (otherwise, you must resize video prior to encoding, hence losing
data or creating more data).
Bye! (sorry if I'm off-topic, non-developer here)
<p>--- >8 ----
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