Here´s an update. I tried around removing and adding the variuos changes you made to the cmdline.txt - but I must say it does not make so much of a difference. I can say that the latest firmware made a huge difference - the webcam runs smoother since then. But still, it does not run properly: With xawtv I see image distortions every few seconds. When I add further USB traffic, like moving the mouse, things go from bad to worse - the image distortions are much more frequent.
Next try I gave motion. This produces a CPU load of about 30% max. But I get image errors every few seconds also:
Code: Select all
[1] Started stream webcam server in port 8081
Corrupt JPEG data: premature end of data segment
[1] File of type 8 saved to: /tmp/motion/01-20130225221351.swf
[1] File of type 1 saved to: /tmp/motion/01-20130225221351-00.jpg
[1] File of type 1 saved to: /tmp/motion/01-20130225221351-01.jpg
[1] File of type 1 saved to: /tmp/motion/01-20130225221352-00.jpg
[1] File of type 1 saved to: /tmp/motion/01-20130225221352-01.jpg
[1] File of type 1 saved to: /tmp/motion/01-20130225221353-00.jpg
[1] File of type 1 saved to: /tmp/motion/01-20130225221353-01.jpg
[1] File of type 1 saved to: /tmp/motion/01-20130225221354-00.jpg
[1] File of type 1 saved to: /tmp/motion/01-20130225221354-01.jpg
[1] File of type 1 saved to: /tmp/motion/01-20130225221355-00.jpg
[1] File of type 1 saved to: /tmp/motion/01-20130225221355-01.jpg
Corrupt JPEG data: premature end of data segment
[1] File of type 1 saved to: /tmp/motion/01-20130225221356-00.jpg
[1] File of type 1 saved to: /tmp/motion/01-20130225221356-01.jpg
Corrupt JPEG data: premature end of data segment
[1] File of type 1 saved to: /tmp/motion/01-20130225221357-00.jpg
[1] File of type 1 saved to: /tmp/motion/01-20130225221357-01.jpg
[1] File of type 1 saved to: /tmp/motion/01-20130225221358-00.jpg
[1] File of type 1 saved to: /tmp/motion/01-20130225221358-01.jpg
[1] File of type 1 saved to: /tmp/motion/01-20130225221359-00.jpg
[1] File of type 1 saved to: /tmp/motion/01-20130225221359-01.jpg
[1] File of type 1 saved to: /tmp/motion/01-20130225221400-00.jpg
[1] File of type 1 saved to: /tmp/motion/01-20130225221400-01.jpg
[1] File of type 1 saved to: /tmp/motion/01-20130225221401-00.jpg
[1] File of type 1 saved to: /tmp/motion/01-20130225221401-01.jpg
[1] File of type 1 saved to: /tmp/motion/01-20130225221402-00.jpg
[1] File of type 1 saved to: /tmp/motion/01-20130225221402-01.jpg
[1] File of type 1 saved to: /tmp/motion/01-20130225221403-00.jpg
[1] File of type 1 saved to: /tmp/motion/01-20130225221404-00.jpg
Corrupt JPEG data: premature end of data segment
Corrupt JPEG data: premature end of data segment
Corrupt JPEG data: premature end of data segment
Corrupt JPEG data: premature end of data segment
Corrupt JPEG data: 14191 extraneous bytes before marker 0xd9
JPEG datastream contains no image
[1] Video device fatal error - Closing video device
[1] Closing video device /dev/video0
[1] Retrying until successful connection with camera
[1] cap.driver: "ov519"
[1] cap.card: "USB Camera"
[1] cap.bus_info: "usb-bcm2708_usb-1.2"
[1] cap.capabilities=0x85000001
[1] - VIDEO_CAPTURE
[1] - READWRITE
[1] - STREAMING
[1] Config palette index 8 (YU12) doesn't work.
[1] Supported palettes:
[1] 0: JPEG (JPEG)
[1] Selected palette JPEG
[1] Test palette JPEG (320x240)
[1] Using palette JPEG (320x240) bytesperlines 320 sizeimage 29390 colorspace 00000007
[1] found control 0x00980900, "Brightness", range 0,255
[1] "Brightness", default 127, current 127
[1] found control 0x00980902, "Saturation", range 0,255
[1] "Saturation", default 127, current 127
[1] mmap information:
[1] frames=4
[1] 0 length=32768
[1] 1 length=32768
[1] 2 length=32768
[1] 3 length=32768
[1] Using V4L2
Corrupt JPEG data: 6215 extraneous bytes before marker 0xd9
So one can see that there are data losses inbetween. At the end of the capture above it becomes so bad that motion restarts its connection to the camera. Again, I get more errors when adding USB traffic, CPU still well below 50%.
The USB Soundcard and TV card show the same behaviour as before.
I am not an expert (far from it), but to me it looks like the Pi is not quick enough to handle the interrupts from USB and does not grab data fast enough from the buffers so they get overwritten once in a while. But this is just a wild shot.
By the way: I fianlly measured my TP1/TP2 volatge: its stable at 4.87V - this should be fine according to the Wiki.