On Tue, 17 Oct 2006, Rumjantsev Egor wrote: > Hello. > I develop a driver for USB 2.0 camera. I need to transfer about 22 Mb/s > of video data from it. Also i need to know some information about > internal camera's state and i use for it usb_control_msg function. I > call usb_control_msg about 1-2 times per second. After starting of > stream of video data i noticed that some part of data is lost. I find > out that this loosing of data can be after call usb_control_msg. If i > didn't call it nothing is lost.
What do you mean, data is lost? Do you mean that some of the video data URBs fail? Or do you mean that the camera doesn't transfer as much data as you expect? Or do you mean something else? > I receive data with 4 urb in queue. I tried to change the size of urb > (4096...61440 bytes) but it didn't help - the data is lost > So i'd like to know why this happened. I understand that usb_control_msg > isn't finished until its callback function not called or timeout is not > finished but i though that data receive process not freeze in that moment. > I use Mandriva 2006; Kernel version 2.6.13.5 Maybe the camera doesn't like to handle control messages while it is transferring video data. Alan Stern ------------------------------------------------------------------------- Using Tomcat but need to do more? Need to support web services, security? Get stuff done quickly with pre-integrated technology to make your job easier Download IBM WebSphere Application Server v.1.0.1 based on Apache Geronimo http://sel.as-us.falkag.net/sel?cmd=lnk&kid=120709&bid=263057&dat=121642 _______________________________________________ [email protected] To unsubscribe, use the last form field at: https://lists.sourceforge.net/lists/listinfo/linux-usb-devel
