[FFmpeg-devel] [PATCH] Extract rotation in MOV metadata

[Baptiste Coudurier]

On 04/06/2011 03:19 AM, Michael Niedermayer wrote:
> On Wed, Apr 06, 2011 at 09:51:33AM +0200, Jean-Daniel Dupas wrote:
>>
>> Le 6 avr. 2011 à 02:50, James Zern a écrit :
>>
>>> On Tue, Apr 5, 2011 at 16:53, Baptiste Coudurier
>>> <baptiste.coudurier at gmail.com> wrote:
>>>> Hi Dave,
>>>>
>>>> On 04/05/2011 04:49 PM, Dave Badia wrote:
>>>>> On Wed, Mar 30, 2011 at 11:18 AM, Baptiste Coudurier
>>>>> <baptiste.coudurier at gmail.com> wrote:
>>>>>> Hi Dave,
>>>>> <snip>
>>>>>>
>>>>>> --
>>>>>> Baptiste COUDURIER
>>>>>> Key fingerprint                 8D77134D20CC9220201FC5DB0AC9325C5C1ABAAA
>>>>>> FFmpeg maintainer                                  http://www.ffmpeg.org
>>>>>> _______________________________________________
>>>>>> ffmpeg-devel mailing list
>>>>>> ffmpeg-devel at ffmpeg.org
>>>>>> http://ffmpeg.org/mailman/listinfo/ffmpeg-devel
>>>>>>
>>>>>
>>>>> Thanks for the feedback as I am very new to ffmpeg.
>>>>> I've revised my patch per you suggestions, hope I understood  properly.
>>>>>
>>>>>
>>>>> Interrogate MOV metadata for orientation of video so that software can
>>>>> determine if the video needs to be rotated.
>>>>> ---
>>>>>  libavformat/mov.c |    4 ++++
>>>>>  1 files changed, 4 insertions(+), 0 deletions(-)
>>>>>
>>>>> diff --git a/libavformat/mov.c b/libavformat/mov.c
>>>>> index 23ba1d4..b12890f 100644
>>>>> --- a/libavformat/mov.c
>>>>> +++ b/libavformat/mov.c
>>>>> @@ -1907,6 +1907,10 @@ static int mov_read_tkhd(MOVContext *c, AVIOContext *pb,
>>>>> MOVAtom atom)
>>>>>      sc->width = width >> 16;
>>>>>      sc->height = height >> 16;
>>>>>
>>>>> +    if (display_matrix[0][0] == -65536 && display_matrix[1][1] == -65536) {
>>>>> +         av_metadata_set2(&c->fc->metadata, "rotate", "180", 0);
>>>>> +    }
>>>>
>>>> Set the metadata on AVStream, not AVFormatContext.
>>>>
>>>> Are you sure that the check is 100% correct for the rotation ?
>>
>> why not extracting the whole affine transform matrix ?
> 
> +1
> 
> but that doesnt mean i have any objections to just extract the
> rotation

That would be nice, but I would apply Dave patch (plus the AVStream
metadata change) right now if it is 100% correct and won't cause side
effects. Is the check correct currently ?

-- 
Baptiste COUDURIER
Key fingerprint                 8D77134D20CC9220201FC5DB0AC9325C5C1ABAAA
FFmpeg maintainer                                  http://www.ffmpeg.org