Hi Brandon, first thanks a lot for your work.
On 03/31/2010 08:22 AM, Brandon Mintern wrote:
On Wed, Mar 31, 2010 at 5:47 AM, Benoit Fouet<[email protected]> wrote:
Hi,
On Wed, 31 Mar 2010 00:43:50 -0400 Brandon Mintern wrote:
I am happy to present my first-ever open source code contribution, a
"fade" filter for libavfilter! Here is some example usage:
# Fade in first 30 frames of video
ffmpeg -i input.avi -vfilters fade=in:1:30 output.avi
# Fade out last 45 frames of a 200-frame video
ffmpeg -i input.avi -vfilters fade=out:156:45 output.avi
# Fade in first 25 frames and fade out last 25 frames of a 1000-frame video
ffmpeg -i input.avi -vfilters "fade=in:1:25, fade=out:976:25" output.avi
Would it be possible to (also ?) make it work as follow ?
ffmpeg -i input -vfilters "fade=in:25, fade=out:25"
That's to say: begin fade in at frame 0 and finish fade out at last frame.
Ben
The fade=in:25 is something I could do. Unfortunately the filter has
no information regarding total number of frames until it reaches the
end of the input stream (at least to my knowledge), so the fade=out:25
would not work without buffering frames. It should be
somewhat-trivial, however, to use ffprobe or something similar
beforehand in order to get the total duration and multiply that by the
FPS in order to get the total frames in the video. That's the way I
plan to do it.
>
Hmm... I just thought of an idea that should work. For fade=out we
could buffer frame_length frames until we hit the end of the video,
then start outputting the fading frames. Unfortunately, this is beyond
my knowledge of libavfilter at the moment, and I would rather get this
initial version accepted before adding more functionality to it. This
is definitely something I will keep in mind though, because this seems
to be how most people would like to use fade.
Indeed, I thought about that as well, that could be an idea, and would
help getting "buffering" mechanism implemented :)
--
Baptiste COUDURIER
Key fingerprint 8D77134D20CC9220201FC5DB0AC9325C5C1ABAAA
FFmpeg maintainer http://www.ffmpeg.org
_______________________________________________
FFmpeg-soc mailing list
[email protected]
https://lists.mplayerhq.hu/mailman/listinfo/ffmpeg-soc
