Feature request: String input for device ID and no default device ID

[otl]

Feature request: String input for device ID and no default device ID

[falkoschindler]

I'd like to request this feature as well.

In order to distinguish multiple cameras I generate symlinks like /dev/logitech to /dev/video0 using /etc/udev/rules.d/. With an integer device id I can't be sure which camera is which device after rebooting. A string would allow to open the Logitech camera explicitly.

[OTL]

Hi

It seems possible to use ~file parameter to set device file.
(I have not tested yet, just read the code)

Could you try ~file param?

[falkoschindler]

Unfortunately, using the file parameter yields an error:

cv camera open failed: file /dev/logitech cannot be opened.

[OTL]

thanks!

below link shows that nobody answers the question "how to open with device file path".

http://stackoverflow.com/questions/20266743/using-device-name-instead-of-id-in-opencv-method-videocapture-open

If you find the answer, please let me know!

[falkoschindler]

Yes, I've also seen this post.

Don't you think one of the two answers might work in your case? If you follow the symbolic link /dev/logitech and get the path of the actual device /dev/video42, you might be able to extract the device id 42.

[OTL]

I really know what you want, why you want, because I also have experienced exactly same situation for several time.

My concern is

• Is it portable (at least, it should work on osx, possibly windows...)?
• I don't want to add dependencies like boost::filesystem, if possible.

Isn't it possible to use static video number using udev?

[falkoschindler]

I totally understand your concerns.

I'll look into assigning static video numbers using udev, as you suggest. It can take some time, since it's currently not my main focus. I just found cv_camera, liked it for its nodelet functionality, but struggled with the device id and, thus, quickly voted for this feature request. :)

[mgmeedendorp]

Hi,

It seems that the StackOverflow question linked earlier (here) has finally been answered, so this would resolve this issue.

[OTL]

It seems great. waiting PR. 2017/09/28 14:35 "Maurice Meedendorp" <[email protected]>:

…

Hi, It seems that the StackOverflow question linked earlier (here <https://stackoverflow.com/questions/20266743/using-device-name-instead-of-id-in-opencv-method-videocapture-open> has finally been answered, so this would resolve this issue. — You are receiving this because you commented. Reply to this email directly, view it on GitHub <#4 (comment)>, or mute the thread <https://github.com/notifications/unsubscribe-auth/AAMpJsTGtk2tLPNh4tKCJdc9zmTVGdNPks5smzAGgaJpZM4IVkG7> .

[mgmeedendorp]

I posted a PR on this issue #8

[OTL]

Thank you! Added some small comments. Could you fix them?

[OTL]

merged