[FFmpeg-devel] Scale filter bug
openworld at uralweb.ru
Fri Dec 9 22:22:16 CET 2011
On 10.12.2011, at 1:12, Michael Niedermayer wrote:
> On Fri, Dec 09, 2011 at 08:01:26PM +0500, Alexander Bokovikov wrote:
>> Hi, All,
>> The scale filer being applied to produce M4V or MP4 file format
>> inserts wrong pixel aspect ratio box, and incorrectly sets the frame
>> size in the track header box. As a result target aspect ratio is the
>> same as source file aspect ratio, though I've defined target width
>> and height explicitly. The same effect appears if I use -s WxH
>> parameter instead of -vf scale=W:H one.
>> As I believe the problem is here:
>> [SAR 25:36 DAR 5:3]
>> instead of
>> [SAR 1:1 DAR 12:5]
>> Changing the values by manual boxes editing I get correct movie.
>> I.e. the problem isn't in a wrong stream encoding, but just in wrong
>> MP4 boxes writing. Taking into account that 12:5 = (36x5)/(25x3)
>> (see digits above), I believe the bug is in these calculations -
>> wrong digits are at wrong places. Something like that.
>> Here is the source FLV file:
> wget http://home.bokovikov.com/ffmpeg/video5.flv
> --2011-12-09 21:09:11-- http://home.bokovikov.com/ffmpeg/video5.flv
> Resolving home.bokovikov.com... 188.8.131.52
> Connecting to home.bokovikov.com|184.108.40.206|:80... connected.
> HTTP request sent, awaiting response... 404 Not Found
> 2011-12-09 21:09:12 ERROR 404: Not Found.
I'm so sorry! It's case-sensitive... Please try again, it should work
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