# Video capture properties to UVC control mappings

**URL:** <https://forum.opencv.org/t/video-capture-properties-to-uvc-control-mappings/17673>\
**Category:** C++\
**Tags:** videoio\
**Created:** [May 17, 2024, 6:20am UTC](https://forum.opencv.org/t/video-capture-properties-to-uvc-control-mappings/17673 "2024-05-17T06:20:19Z")\
**Posts on this page:** 2\
**Page:** 1

<div class="post-metadata">

**Author:** ![shiva](https://sea2.discourse-cdn.com/flex020/user_avatar/forum.opencv.org/shiva/32/8483_2.png) [@shiva](https://forum.opencv.org/u/shiva)\
**Post date:** [May 17, 2024, 6:20am UTC](https://forum.opencv.org/t/video-capture-properties-to-uvc-control-mappings/17673/1 "2024-05-17T06:20:19Z")

</div>

Hello everyone,

I am a firmware engineer and quite new to OpenCV. Kindly bear with my limited expertise.

OpenCV version - 4.9.0  
IDE - Microsoft Visual studio 2022 17.9.6

I have a device which outputs USB video and I have an OpenCV application that is running on my host takes this video. USB video control interface provides 19 controls through which host can set hardware parameters.

From my OpenCV application, with video.set() I could set the following.  
CAP\_PROP\_BRIGHTNESS → UVC brightness  
CAP\_PROP\_GAIN → UVC gain  
CAP\_PROP\_BACKLIGHT → UVC backlight  
CAP\_PROP\_SATURATION → UVC saturation  
CAP\_PROP\_SHARPNESS → UVC sharpness  
CAP\_PROP\_GAMMA → UVC gamma  
CAP\_PROP\_HUE → UVC hue  
CAP\_PROP\_CONTRAST → UVC contrast

I couldn’t figure out how to adjust other controls such as  
D6: White Balance Temperature  
D7: White Balance Component  
D10: Power Line Frequency  
D11: Hue, Auto  
D12: White Balance Temperature, Auto  
D13: White Balance Component, Auto  
D14: Digital Multiplier  
D15: Digital Multiplier Limit  
D16: Analog Video Standard  
D17: Analog Video Lock Status  
D18: Contrast, Auto

I am not really using these controls to control what exactly they say, since I can program the USB device, I have customized them for some other purposes. So, I just want to know which of the video io flags in OpenCV map to actual UVC controls.

Thank you.

---

<div class="post-metadata">

**Author:** ![laurent.berger](https://avatars.discourse-cdn.com/v4/letter/l/ec9cab/32.png) [@laurent.berger](https://forum.opencv.org/u/laurent.berger)\
**Post date:** [May 17, 2024, 7:27am UTC](https://forum.opencv.org/t/video-capture-properties-to-uvc-control-mappings/17673/2 "2024-05-17T07:27:46Z")

</div>

I think you can find in doc :  
[https://docs.opencv.org/4.x/d4/d15/group\_\_videoio\_\_flags\_\_base.html#ga023786be1ee68a9105bf2e48c700294d](https://docs.opencv.org/4.x/d4/d15/group __videoio__ flags__base.html#ga023786be1ee68a9105bf2e48c700294d)

It does not mean all flags will set your camera