[mythtv-users] transcoded nuv/mpeg4: really mpeg4?

Brian J. Murrell brian at interlinx.bc.ca
Thu Aug 18 17:30:40 UTC 2005

On Thu, 2005-08-18 at 13:43 -0400, Isaac Richards wrote:
> AVI assumes that audio + video data is at a constant framerate.

Ahhh.  OK.

> It doesn't 
> have any concept of timestamps.  For regular TV, that's just not true.  For 
> stuff recorded by a soundcard, that's even less true - the soundcard's clock 
> varies over time.


> You ask for 48000 samples per second, and what you get 
> won't be that exactly, and will change over time as well.


> In a nuv file, each frame of video, and each packet of audio has a timestamp 
> associated with it.

I don't know much about OGG either, but would NUV re-contain into an OGG
container any better?

> There are also additional constructs for dealing with 
> skipping individual frames (for exact frame-level cuts during a transcode 
> without reencoding), and other various things that make it rather ideal for 
> dealing with stuff recorded from a tuner card.

Are those in the MPEG4 stream or the NUV container?  They probably could
be dropped assuming OGG were better suited to re-containing (i.e. if it
has timestamps, etc.)


My other computer is your Microsoft Windows server.

Brian J. Murrell
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