Video format ofVideoGrabber

Hello,

I started to use webcam with openframeworks. I downloaded a good openframeworks example in this link.

http://vormplus.be/blog/article/mirroring-video-with-openframeworks

I try it but It didn’t work. I looked at terminal and I couldn’t see this error:

[warning] ofGstVideoUtils not loaded.

So, I changed the webcam (less powerful) and It worked!
After I saw that program selects RGB-format with the old camera and the program with new camera selects

[notice] ofGstUtils: selected defice: UVC Camera (…)
[notice] ofGstUtils: selected format: 640x480 image/jpeg framerate: 60/1
[notice] gstramer pipeline: v42lsrc name=video_source device=/dev/video0 ! image/jpg,width=640,height=480,framerate=60/1 ! videoconvert ! appsick name=ofappsick caps=“video/x-raw, format=RGB, with=640, height=480”
[error] couldnt create pipeline: no se puede enlazar video_source a videconvert0
([error] coulnt create pipeline: It can’t link video_source to videoconvert0)

So, I changed the with and height to 1280x960 and the program with new camera works.

[notice] ofGstUtils: selected defice: UVC Camera (…)
[notice] ofGstUtils: selected format: 1280x960 video/x-raw RGB framerate: 15/1
[notice] gstramer pipeline: v42lsrc name=video_source device=/dev/video0 ! image/jpg,width=1280,height=960,framerate=15/1 ! videoconvert ! appsick name=ofappsick caps=“video/x-raw, format=RGB, with=1280, height=960”
[ofVideoGrabber:warning] setPixelFormat - can’t be called while the grabber is running

But I want the program to use the 640x480 in the new camera so I looked for the config class. I found this method:
setPixelFormat(…)
But the parameter only can be:
enum ofPixelFormat{
OF_PIXELS_MONO = 0,
OF_PIXELS_RGB,
OF_PIXELS_RGBA,
OF_PIXELS_BGRA,
OF_PIXELS_RGB565
};

How can I select image/jpg format?
or:
How can I force the program to select vide/x-raw RGB format from the camera?

Thank you!