[MPlayer-users] Re: Can mencoder write partial files while encoding?

[Alban Bedel]

Hi Rainer Hantsch,

on Fri, 29 Aug 2003 11:42:21 +0200 (CEST) you wrote:

> [Automatic answer: RTFM (read DOCS, FAQ), also read
> DOCS/bugreports.html] On Fri, 29 Aug 2003, Alban Bedel wrote:
> 
> | Hi Ryan Voots,
> | > well since it is tv shows its too bad that you couldn't detect when
> | > commercials are going to break it apart then, but i think that is
> | > besides the point of your question
> | I got a little idea for this long ago. I have no idea how doable it is
> | but here it is: Most tv channel put their logo somewhere on the screen
> | but not during commercials. As these logo are small it shouldn't be
> | too cpu intensive to watch for them.
> 
> I surely have other priorities for the moment.
> Currently I feel myself fighting against windmills. I found now a _very_
> CPU intensive setup which compresses into DivX @ 640x400px. My Celeron
> 1700 is loaded to nearely 95%, but it works, so I get good image quality
> at a better compression. (I use now degauss3d again, pp=tn produces much
> bigger files because it lets more noise remain in the video.)
I also go for the best encoding quality and take care of the commercials
myself. Indeed a good commercial detector is in the dreams of all tv
encoders ;)

> | However this woudldn't be perfect as tv channels uselly show this logo
> | also during their "omn commercial" (the next show, film of tomorow,
> | etc). Until now it's the only idea i got wich seems both cpu friendly
> | and reliable (at least within its own limits).
> | Did someone got some other idea on this topic ? Perhaps that by
> | combining some other strange ideas we can get something good ;)
> | 	Albeu
> 
> The situation is more worse: Many TV stations (as RTL-II) have sometimes
> animated logos on the screen, also sometimes in different locations.
> Often, they also change their size when the film is in 16:9. How would
> you get this under control?
Yes you'r right it's not so simple and it depend a lot on the channel.
But as you said: "sometimes" Most of the time these logo just stay there
and the animations are always the same. So except if you start in middle
of an animation you don't need to check each frame of the animation.

I remeber somebody tried to do a filter wich looked for black frames.
This is just way too cpu intensive and imho too unreliable (at least here
in europe). However if you just need to check a small part of the screen
you can easily do more advanced checks. Getting some information from the
codec like quantizer and motion vectors of the macro block we are looking
at could probaly help a lot if the source is alredy encoded (or beeing
encoded ;)
	Albeu
-- 

Everything is controlled by a small evil group
to which, unfortunately, no one we know belongs.