[GnomeMeeting-list] Scaling video from 640x480 with the ov511 driver

[James Bunton <james delx cjb net>]

> I also have OV511 and here it does scale fine.. Maybe this is my camera
> or your driver is too old..
Nah, I'm using the latest 2.x driver (2.27 I think).
Maybe your camera only goes up to 352x288?


> try with the loopback v4l driver and effectv.. maybe you're lucky and
> can resize in the loopback.. that way you don't need to hack any code..
> (but if you do, please send in the patches to us instead of making them
> laying around the net and become forgotten about)

Thanks for the suggestion of vloopback!

I got it working fine, if a little bit of a hack. So I'll just post how I did 
it here for anybody to see later. (not sure if this is applicable to go in 
the GnomeMeeting docs?)

You need to download the vloopback module from here
http://motion.technolust.cx/vloopback/

Untar it to some place, and change to that directory
Check the Makefile to ensure that the INCLUDEDIR points to your kernel headers 
(usually /usr/src/linux)
Compile the module and insert it into the kernel. I had to provide the module 
options dev_offset=2 (I have two video4linux devices and it crashed when it 
didn't detect that). So..

make
insmod vloopback.o dev_offset=2

Then change to the examples directory
Edit resize.c to change wherever it says RGB24 to YUV420P (there should be 
two)
Run make again to compile the files in that directory.

Now run resize.

./resize /dev/video1 /dev/video2 640x480 352x288

The option is your camera's device (my tv card is video0), the second is the 
input stream that vloopback creates (it will be different if you didn't use 
dev_offset=2), the third is the max resolution of your camera, and the last 
is the highest resolution that GnomeMeeting will accept.


Hope that helps somebody later on..


---

James