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

[James Zern]

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
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>>
>> 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 ?
>
Couldn't this be more generically extracted as the acos of [0][0] then
verified against [1][1]?