[Libav-user] API usage of the overlay avfilter

[Alex Cohn]

On Tue, Apr 17, 2012 at 17:19, Adolfo Bulfoni <abulfoni at h-art.it> wrote:
> Hi,
>
> I've started using FFMPEG library for an Android project.
> I've successfully compiled it for armv7 architecture, also including the avfilter library.
> My target is to develop  a JNI function that uses the overlay filter to overlay two .mp4 videos together.
> this is the filter:
>
> Do you know any API examples of usage of overlay filter or similar filters? In the official samples I've found only two examples, encoding-example.c and muxing-example.c but they don't use filters.
>
> Thanks everybody in advance
>
> Adolfo

I would consider using OpenGL for overlaying the videos, using
semi-transparent textures. I believe that OpenGL gives you a lot of
effects without using too much CPU. Also, Android has built-in
stagefright library to decode mp4 videos which may use hardware codec
if available (typically, for h264). This also saves CPU consumption
and extends battery life.

BR,
Alex Cohn