[gst-devel] Video mixing problems

[Josep Creus Portolés]

Hello there,

We are going to use Premier if I cannot solve this. I don't want it.
I'm trying to use videomixer, videoscale, videobox and ffdeinterlace to 
compose a video beginning with tree streams.

This is the actual script, obviously the xvimagesink filter is 
substituted by a codec compressor filter.

gst-launch-0.10 filesrc location="video1.mpg" \
{ ! decodebin2 ! ffdeinterlace ! queue2 ! videocrop left=6 right=8 top=2 
bottom=6 ! videoscale method=2 ! video/x-raw-yuv, width=454, height=358 
! videobox border-alpha=0 alpha=1 right=-266 top=-124 bottom=-94 ! 
ffmpegcolorspace ! videomixer name=mix ! xvimagesink } \
{ filesrc location="video2.mpg" ! decodebin2 ! ffdeinterlace ! queue2 ! 
videocrop left=6 right=8 top=2 bottom=6 ! videoscale method=2 ! 
video/x-raw-yuv, width=268, height=224 ! videobox border-alpha=0 alpha=1 
left=-452 top=-138 bottom=-214 ! ffmpegcolorspace ! mix. } \
{ multifilesrc location="backgorund.png" num-buffers=102959 ! image/png, 
framerate=25/1 ! pngdec ! queue2 ! ffmpegcolorspace ! mix. }

AFAIK, ffdeinterlace only works with I420 colorspace, videocrop, 
videoscale and videobox has no problem working with it, but it seams 
that there is no alpha channel, and that makes the chain unusable, only 
the second video stream is visible with all black bars around. Any ideas 
on how can I solve this? I've tried using alpha filter, but then the 
chain is not prerolling at all, whichever method I choose.

Besides that, I don't see GStreamer using the format property at all, 
how has it to be entered? In GStreamer 0.8 it was something like 
format=/fourcc/

And videobox 0.10.16 is supposed to have the autocrop properties, 
GStreamer web documentation says so, but it have not. To whom I have to 
report this?

Oh! I almost forget it, I'm using Ubuntu 9.10.

Greetings and thanks in advance for any help.
Josep