[FFmpeg-devel] [PATCH] Write Pixel Aspect Ratio tag to QuickTime files

Tim Dewhirst tim
Thu Jul 8 10:10:53 CEST 2010


Baptiste Coudurier wrote:
> On 07/07/2010 02:17 PM, Daniel Kristjansson wrote:
>> On Wed, 2010-07-07 at 13:37 -0700, Baptiste Coudurier wrote:
>>> Hi,
>>> On 07/07/2010 10:24 AM, Daniel Kristjansson wrote:
>>>> This allows for non-square pixels in QT containers regardless
>>>> of codec. 'pasp' is also a required tag in Apple QT when the
>>>> pixels are not square.
>>> I doubt this is required.
>>> How does quicktime do with mp4 that did only define pasp until 
>>> recently ?
>> It's required in the spec, p118 of qtfs.pdf, "Pixel aspect ratio. This
>> extension is mandatory for video formats that use non-square pixels."
> My specs say MPEG-4 and uncompresed YCbCr. Dated 2007-09-04
>> The QuickTime player (shows 1440x1080 MPEG-2 material at 36:27 rather
>> than 16:9 without this. I did not test whether NTSC/PAL material is
>> played correctly.
> What kind of mpeg-2 using which codec ?
> Can you share a sample ?

XDCAM-HD 35Mb/s is 1440x1080 (as opposed to XDCAM-EX 35Mb/s which is 


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