[FFmpeg-devel] [PATCH] OpenEXR decoder rev-3

Jimmy Christensen jimmy
Thu Jul 2 07:54:32 CEST 2009

On 2009-07-01 23:24, Reimar D?ffinger wrote:
> On Wed, Jul 01, 2009 at 11:00:14PM +0200, Jimmy Christensen wrote:
>> It's stated in the documentation for the fileformat :
>> The line offset table allows random access to scan line blocks. The
>> table is a sequence of scan line offsets, with one offset per scan line
>> block. A scan line offset, of type unsigned long, indicates the
>> distance, in bytes, between the start of the file and the start of the
>> scan line block. In the table, scan line offsets are ordered according
>> to increasing scan line y coordinates.
>> I would suspect that the idea perhaps is that on 64-bit systems it can
>> use the full range, but not on 32-bit systems.
> unsigned long is also 32 bit on 64 bit Windows systems.
> Either the documentation does not use the C meaning of that (what else?),
> the part you quoted lacks context, or the documentation is just braindead.
> Since you're probably not going to work with asm code, just remember the
> simple rule: if you are using "long" you are doing something wrong.

The documentation is here :

After re-reading it, I found that it does say what it means exactly with 
"unsigned long", so will change it specifically to that. Didn't know 
there were such a difference in Windows (not surprised either).

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