Image corruption

[hjetschko]

I have the same problem as another issue that was closed. The image gets corrupted but it is blocked that are out of place. Sometimes the blocks have different brightness, suggesting that the blocks comes from different frames. A corrupted image can be seen at: http://www.i2cchip.com/fswebcam/lastImage.jpg Initially I thought the voltage dips while taking an image. I used a powered hub and used an oscilloscope to confirm that the voltage does not dip but it still happens. I am using fswebcom on a TP Link WR703N running Openwrt.

[fsphil]

There may not be enough bandwidth on the USB bus (shared with other devices?) or something on the host interrupting the transfer. Are there any warnings or errors in dmesg?

[hjetschko]

Hi Philip

Thank you for the help. There are other devices we communicate with on the USB. I stop all other communication when requesting an image transfer and solved the problem. dmesg does not give me any error messages when the image gets corrupted. Thanks again for the help.

I was hoping you could give me advice about another problem. With some webcams, when I specify the resolution then it resets the device. I assume that the resolution I requested is not supported by the device. Is there a way to detect what resolutions are supported by the webcam using fswebcam? The default resolution is fairly small.

Thanks and regards
Hubert Jetschko

From: Philip Heron
Sent: Wednesday, May 22, 2013 8:46 PM
To: fsphil/fswebcam
Cc: hjetschko
Subject: Re: [fswebcam] Image corruption (#7)

There may not be enough bandwidth on the USB bus (shared with other devices?) or something on the host interrupting the transfer. Are there any warnings or errors in dmesg?

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[drng]

I had similar problem and no amount of turning off the USB devices helped, but when i erased an option, then the image was ok.

Example using /usr/bin/fswebcam --no-title --no-banner -i 0 -F 1 -S 5 -D 3 --jpeg 95 -d /dev/video0 -r 800x60

Example using /usr/bin/fswebcam --no-title --no-banner -i 0 -F 1 -S 5 -D 3 --jpeg 95 -d /dev/video (-r option erased)

As you can see, I am Using OpenWRT AA (12.09) on SX763 router (lantiq, danube).
...hope it helps.

[fsphil]

You may be able to list resolutions by running:

$ v4l2-ctl --list-formats-ext

I'm closing this for now as I don't believe the image corruption is an fswebcam issue.

[hiveww]

I have the same issues (pic is corrupted and reboot at resolution higher then 400x400), using arduino yun, openwrt.

At the same time if I use ffmpeg to take a single pic, everything is fine. That's why I think problem is in fswebcam