[FFmpeg-devel] [PATCH] mov tkhd' width and height usage

Maksym Veremeyenko verem
Thu Jan 20 12:55:13 CET 2011

Maksym Veremeyenko ???????(??):
> Hi,
> by default mov muxer setup width and height fields of *tkhd* atom as 
> visual representation of track that is mentioned in *ISO/IEC 14496-12* 
> (http://standards.iso.org/ittf/PubliclyAvailableStandards/c041828_ISO_IEC_14496-12_2005(E).zip) 
> [...]
> width and height specify the track's visual presentation size as 
> fixed-point 16.16 values. These
>    need not be the same as the pixel dimensions of the images, which is 
> documented in the sample
>    description(s); all images in the sequence are scaled to this size, 
> before any overall transformation of
>    the track represented by the matrix. The pixel dimensions of the 
> images are the default values.
> [...]
> but *QuickTime File Format Specification* do not mention about it:
> [...]
> Track width
>        A 32-bit fixed-point number that specifies the width of this 
> track in pixels.
> Track height
>        A 32-bit fixed-point number that indicates the height of this 
> track in pixels.
> [...]
> As result some software fault because of it want to read 768x576 plane 
> instead of 720x576. Furthermore QuickTime, FinalCut, Flipfactory set 
> width and height of *tkhd* equal to codec's width and height on exported 
> mov files.
> Would it be a solution to set width and height equal to codec parameter 
> for mov format only (not mp4 etc..), please find attached patch...


Maksym Veremeyenko

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