[MPlayer-users] splitting avi output

[vin.gui]

>>Always think in MPlayer and/or Mencoder.
>>Yes, you can split your avi file in two. Just look at the precise time
>>when you want the second part to begin (or the first to finish) and
>>write:   "mencoder -ovc copy -oac copy -ss 01:05:23 -o YourFile2.avi
>>YourFile.avi"
>>This for the case that you want the second part to begin after one hour,
>>five minutes and twenty three seconds (as read on your OSD)
>>
>>With that, you will have the second half. Now, lets go to the first
>>part. For that you must use (as long as I now and have done) the
>>"-frames" capability of mencoder. Play your file with mplayer and yo to
>>the place you want to cut your file (in the example: 01:05:23). Click
>>the space key to pause the movie and look to the frame-number in the
>>output of mplayer. Take a note and write:
>>"mencoder -ovc copy -oac copy -frames 98075 -o YouFile1.avi
>>YourFile.avi"
>>
>>The last number is the one that you must have noted. You can always
>>obtain it (as you have 25 frames per second if a standard avi) using:
>>(hours x 3600 + minutes x 60 + seconds) x 25 = your number of frames.
>>
>>With that, you must obtain your two files. Try it and if it doesn't
>>work, do not blame anyone of the MPlayer team. Just me. :-)
> 
> 
> For first chunk you can use:
> mencoder -oac copy -ovc copy -endpos 700mb -o first_chunk.avi bigfile.avi
> too.
> 

Many thanks for your suggestions.
I would actually like to make a SCRIPT cutting the bigfile.avi into 
700MB chunks.
This last suggestion is nice for that: it does not need human interaction.
But as far as I understand, the option -ss cannot be given a file size.
So the creation of the next chunk needs a computation of the time
corresponding to this 700MB point.

One could do that by looking at the time length of the first_chunk.avi.
How can one get this info (I mean with no human interation) ?

There is also the fact that it should start on a keyframe.
Is there a way to tell where is keyframe just before 700MB,
or just before time 1:23:45 ?

Many thanks

Vincent.