| Re: [hatari-users] AVI Record problem -> ODML 64 bit support added |
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Le 11/07/2017 à 15:50, Nicolas Pomarède a écrit :
I see AVI specs 2.0 can have extra AVIX chunks to have > 2GB in the end.
I will try to look at this someday (but it might not be soon)
Hi,
good news, Hatari now support the "OpenDML AVI File Format Extensions
Specification" which extends the basic AVI format limited to 32 bit file
size to handle file size of any size > 4GB.
I made some tests and successfully recorded a 7 GB file which I could
read using VLC (including seeking anywhere using the indexes), some avi
validation programs also reported a correct structure of the file.
For the technical details, the ODML format divides the AVI file in
several RIFF AVI or RIFF AVIX (X=extension) chunks. Each chunks should
be < 4GB but you can have as many as you like and some new "super
indexes" are added to allow referencing position using 64 bit offset.
In Hatari, I arbitrarily fixed the super index size to 256 entries, each
entries would then reference a 1 GB 'movi' chunk.
This requires an OS capable of handling 64 bit file offset, but all
modern OSes will do it.
This means the current limit for an AVI file will now be 256 GB in Hatari :)
Nicolas