Hi,
is it possible to zoom out a little bit in nvdewarper plugin?
When undistort via OpenCV we can see black bars on the image (top & bottom), but when we use nvdewarper plugin looks like the image is cropped.
So my question is: How to prevent that and is it possible at all? We’d like to see as much as possible.
This is the result video for point 1: test.mkv (6.1 MB)
This is the result video for point 2: test_nv.mkv (7.3 MB)
We use the following config file for this video for nvdewarper plugin: nvdwarp_config.txt (289 Bytes)
This is the result video for point 3: test_cv.mkv (4.8 MB)
We use common way via OpenCV to undistort the video and the camera matrix & distortion coeffs are calculated with OpenCV function calibrateCamera during calibration:
Hi,
We have tried to increase the output resolution to 1280x720 and we are able to zoom out a little bit but then the image is not undistorted correctly on the sides. Maybe we have wrong configuration values for nvdewarp plugin because with opencv we can undistort the image, e.g calculation of the focal length we use the following formula:
convert degrees of vertical FOV to radians = 61deg = 1.06465084
pixels per radian = 540px (vertical resolution) / 1.06465084rad (vertical fov in radians)
Try to set third coefficient half or double, and check the effect. If it has effect, please tweak it until the lines straighten out. If it becomes a little wiggly, you may need to tweak the second coefficient too.
Last two coefficients set to 0 & half of third coefficient - test_nv_last_two_coeffs_0_and_third_halfed.mkv (7.2 MB)
There is no big difference among the three videos and they are all not undistorted correctly on the sides.
Do we know the meaning of each of these coefficients, because probably there is a difference in implementations between nvdewarp plugin and opencv undistortion?
Thank you in advance!
Hi,
When we did some changes on all distortion coefficients, we have something similar to OpenCV results (it is not perfect, good combination of undistortion and visibility on the sides).