Why my camera gives only 8FPS in linux using v4l?

[Terminator3]

Resolution 320x240, but frame rate is very low - about 8FPS. Tried two cameras, two different ways: compiled FPC v4l demo source code and tried mplayer from command line. Same camera gives about 20FPS min in windows. Driver issue? What i can do to improve camera FPS under linux?

update: I tried other notebook with faster CPU and get 14 FPS. But still not >20FPS. Light condition are goood. As can be seen, FPS depends on CPU. How i can get high FPS on atom CPU? I want to attach camera to embedded PC with linux, and able to see good frame rate on low resolution image, like 320x240...

 

[Eight]

Which webcam (model) do you have? Also what linux do you use (type "uname -a" in a terminal and post the output)? Most of the recent cameras should be UVC-compatible, and linux uses a general UVC driver for all of them. It's strange that you don't get good framerate. Did you try out the camera at different light condidions? Some webcams will drop the framerate in dark areas, and speed up when there is sufficient light available. Try recording outside a window on a sunny day. Additionally you might want to download and try a program called guvcview (in debian based systems type "sudo apt-get install guvcview" to install it). It gives you various fine-tune options, so you might want to play with them. See, if it offers you to change the framerate to a higher value.


It's also useful to check, if your webcam is supported on linux, or it has some issues.
https://www.ideasonboard.org/uvc/

 

[andre_luis]

Some Webcams allow direct interface to its internal image configuration parameters, so that being the case you could disable the automatic exposure and frame rate and define a fixed one.

 

[Terminator3]

Thank for your replies, i tried guvcview, and it works surprisingly fast. I found out that it uses other image format that program source code i used before. Now when using some yuv or mjpeg it works fast. I guess it was frame skipping or something because of image format converting routines. I use linux mint 32bit, downloaded it recently.