From both the OpenCV documentation and the V4L2 documentation, it is unclear how all the CAP_PROP_... parameters are mapped to v4l2 controls such as exposure_absolute.
However, you can easily look in the source code (int capPropertyToV4L2(int prop) in cap_v4l.cpp) in order to see how the parameters are mapped internally. Github link to the source code
The following table is based on OpenCV 4.x Git revision a001ab3a445b8e1f8f4004a816c1a0232a90bd05.
| OpenCV parameter | V4L2 parameter |
|---|---|
| CAP_PROP_FRAME_COUNT | V4L2_CID_MPEG_VIDEO_B_FRAMES |
| CAP_PROP_BRIGHTNESS | V4L2_CID_BRIGHTNESS |
| CAP_PROP_CONTRAST | V4L2_CID_CONTRAST |
| CAP_PROP_SATURATION | V4L2_CID_SATURATION |
| CAP_PROP_HUE | V4L2_CID_HUE |
| CAP_PROP_GAIN | V4L2_CID_GAIN |
| CAP_PROP_EXPOSURE | V4L2_CID_EXPOSURE_ABSOLUTE |
| CAP_PROP_WHITE_BALANCE_BLUE_U | V4L2_CID_BLUE_BALANCE |
| CAP_PROP_SHARPNESS | V4L2_CID_SHARPNESS |
| CAP_PROP_AUTO_EXPOSURE | V4L2_CID_EXPOSURE_AUTO |
| CAP_PROP_GAMMA | V4L2_CID_GAMMA |
| CAP_PROP_TEMPERATURE | V4L2_CID_WHITE_BALANCE_TEMPERATURE |
| CAP_PROP_WHITE_BALANCE_RED_V | V4L2_CID_RED_BALANCE |
| CAP_PROP_ZOOM | V4L2_CID_ZOOM_ABSOLUTE |
| CAP_PROP_FOCUS | V4L2_CID_FOCUS_ABSOLUTE |
| CAP_PROP_ISO_SPEED | V4L2_CID_ISO_SENSITIVITY |
| CAP_PROP_BACKLIGHT | V4L2_CID_BACKLIGHT_COMPENSATION |
| CAP_PROP_PAN | V4L2_CID_PAN_ABSOLUTE |
| CAP_PROP_TILT | V4L2_CID_TILT_ABSOLUTE |
| CAP_PROP_ROLL | V4L2_CID_ROTATE |
| CAP_PROP_IRIS | V4L2_CID_IRIS_ABSOLUTE |
| CAP_PROP_AUTOFOCUS | V4L2_CID_FOCUS_AUTO |
| CAP_PROP_SAR_NUM | V4L2_CID_MPEG_VIDEO_H264_VUI_EXT_SAR_HEIGHT |
| CAP_PROP_SAR_DEN | V4L2_CID_MPEG_VIDEO_H264_VUI_EXT_SAR_WIDTH |
| CAP_PROP_AUTO_WB | V4L2_CID_AUTO_WHITE_BALANCE |
| CAP_PROP_WB_TEMPERATURE | V4L2_CID_WHITE_BALANCE_TEMPERATURE |