How to tweak a mov file with LC?

Tiemo Hollmann TB toolbook at kestner.de
Thu Sep 24 04:31:46 EDT 2015


Hello,

I have 19000 old MOV videos, which were compressed with Sorenson squeeze. I
used the “Sorenson Video 3” codec, which is “basically” a h.264 codec. The
AVFoundation doesn’t supports the “Sorenson Video 3” codec, only a pure
h.264. Up to now, I don’t know, if this “Sorenson Video 3” is only a
proprietary name of a h.264 codec in the MOV container, which bothers
AVFoundation, or if the codec itself was tweaked by Sorenson, so that it
isn’t compatible with AVF, even if the name would be “h.264”.

 

Mark Waddingham brought up the idea, before recoding all videos with a
current h.264 codec, I could perhaps tweak the “Sorenson Video 3” codec name
in the MOV container on the fly within my LC program, so that my customers
can go on using my old videos with the new AVFoundation. With my limited
knowledge I just tested to read the mov file as binary, search for the
“Sorenson Video 3” string, replace it against “h.264” and write back the
binary file. Probably this isn’t enough to just tweak a text string in the
binary MOV file, at least when I try to play this tweaked video, the
QT-player tells me, that a part of the video file is broken and it can’t be
played.

 

Now I don’t know, if this broken file is because of my naïve approach of
tweaking the codec name in the mov file and there are much more things to
tweak, or because the tweak would be ok, but the used codec actually is so
much different from a h.264, that is doesn’t matches anymore to the tweaked
codec name.

 

Can anybody shed some light on the approach on how to tweak a binary video
file?

 

Thanks

Tiemo

 

 




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