[FFmpeg-devel] Need suggestion for ROTATION

[Tilak Adhya]

Hi All,

I am new to this list. I am trying to add one feature to the
ffmpeg code base regarding the rotation. FFmpeg does not have
any support for frame level rotation. My requirement is to
rotate(90, 180, 270 degrees ) a movie, before streaming.

Now, first we thought that, we would create a new AVPicture
with the new data and linesize fields and rearrange the data[0],
data[1] and data[2] pointers for the rotated movie. But while 
doing this, we faced lot of problems regarding the modification
of data and height and width fields. 
So we decided to first convert this YUV format to RGB format
using img_convert() fuction and then rotate the picture in the
RGB level and then again convert it to the YUV format. But in
this procedure the main concerns are how to rotate a picture in
RGB format and how much feasible this approach is. Actually in 
a 15fps movie the extra operations will be two image conversions
(YUV -> RGB and RGB -> YUV) and rotation in the RGB plane for each
frame. 

Now my question is, which procedure we will take to rotate a movie
and what is the concept of rotation in the YUV plane for a movie.
Need your suggestion in this regard...

Awaiting for your reply.
Thanks in advance...

Regards
litak


*--
tilak