usb_cam_test: explicitly configure contrast and saturation #17
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In commit ros-drivers/usb_cam@b25c2938, contrast and saturation parameters were added to usb_cam. Unfortunately these were hard-coded to somewhat strange values. Both were turned down towards the bottom of the range explaining the low-contrast, low-saturation images. In the same commit, the default focus was set at a very near value leading to blurry images. The combination of these factors lead to the appearance of a very broken webcam indeed. Set the contrast, saturation and focus explicitly in the launch file and add a comment explaining their presence. Launch files which use the usb_cam node should probably explicitly set contrast and saturation from now on.
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@hutchinsonjack, @DuongLe, this should fix the webcam issue. Could you confirm if this is the case and, if so, merge? Thanks. |
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Note that the commit which added this problem is only 21 days old. This probably explains why the problem does not happen on the desktop. Since the Docker image on that machine is older than 21 days and has not been invalidated via the --no-cache option, the version of the usb_cam node on that machine is too old to exhibit this problem. Should this PR address our issue, I suggest than an issue be opened upstream explaining our problem, pointing them to this PR and asking that, at the very least, their documentation be updated to note the presence of these parameters. I only discovered them by poking at the source code. |
The contrast, saturation, brightness, sharpness and focus parameters were recently added to usb_cam. This caused a regression (sigproc/robotic_surgery#17) whereby the default settings for a webcam are overridden in all cases by the hard-coded defaults in usb_cam. In the absence of a know good set of "default" values, leave the parameters unset unless the user has explicitly set them in the launch file.
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I fixed the documentation at http://wiki.ros.org/usb_cam to actually mention these parameters. I opened ros-drivers/usb_cam#24 to stop this happening to anyone else. |
usb_cam_test: explicitly configure contrast and saturation
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It works nice and perfectly 😃 |
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Excellent. |
In commit ros-drivers/usb_cam@b25c2938, contrast and saturation
parameters were added to usb_cam. Unfortunately these were hard-coded to
somewhat strange values. Both were turned down towards the bottom of the
range explaining the low-contrast, low-saturation images.
In the same commit, the default focus was set at a very near value
leading to blurry images.
The combination of these factors lead to the appearance of a very broken
webcam indeed.
Set the contrast, saturation and focus explicitly in the launch file and
add a comment explaining their presence. Launch files which use the
usb_cam node should probably explicitly set contrast and saturation from
now on.