J721EXCPXEVM: Surround View display is dirty

Hello,

To remove the partial view of license plate, you have to camera position or orientation.

The poor output quality can be due to multiple reasons. First of all, you need to check your camera (intrinsic) parameters are accurate enough. I see the output images have large distortion in the left and right sides. The line in the left side is not even straight, which may come from inaccurate camera parameters. 

In the last bird's eye view image, two rear charts are completely from the rear camera. It is better to adjust cameras' poses or charts' position so that a chart is reconstructed from two cameras. (i.e. the stitching line goes though the center (or close to center) of a chart.

Dear Do-Kyoung Kwon,

I provide the original image of my test. From the picture, you can find that the installation position of these fisheye lenses is the installation position of general fisheye lenses.

Moreover, when I tested these pictures in Surround View on other platforms, there was no such obvious license plate afterimage.

Can't these afterimages be corrected through Surround View when doing puzzles?
I removed the car view and the afterimages of the front and rear license plates were even more obvious!!

Best regard,
George Lin

Hello George,

I cannot comment on the output image on another platform. But the car image here looks relatively larger than the car image in TI platform. You will be able to hide license plate by increasing the car image size. However, the calibration doesn't look right. So I recommend you to adjust camera poses and recalibrate.

Dear Do-Kyoung Kwon,

Regarding TI Surround View, I currently only have the file PSDK_RTOS_UserGuide_3D_SurroundView_Manual_CalibTool.pdf. So regarding "adjust camera poses", does TI have documentation to provide installation suggestions? Otherwise, the installation engineer can only install it based on previous experience, and the results will be similar to the current results.
Also, I have uploaded the original image taken by our fisheye camera, and it looks normal. I wonder if you have any specific suggestions for "adjust camera poses" after reading this?

Best regard,
George Lin

Dear Do-Kyoung Kwon,
about
"In the last bird's eye view image, two rear charts are completely from the rear camera. It is better to adjust cameras' poses or charts' position so that a chart is reconstructed from two cameras. (i.e. the stitching line goes though the center (or close to center) of a chart."
I test the second set of patterns. And this time the position of the pattern has indeed been adjusted to be closer to the car. But the problem you mentioned still occurs.
<Original test>

<The second test>

So the problem may not be related to the position of the pattern, but to the position of the camera settings. However, the position of the left and right cameras is originally set below the left and right rear view mirrors, so of course it is more forward.

Do you recommend setting the left and right cameras in the middle of both sides of the car?

Best regard,

George Lin

George,

I think it is normal to install left and right cameras at mirrors. In my opinion, it is better to make the distance between pattern1/2 and pattern 4/3 (i.e. horizontal distance between patterns). And the original test looks better in terms of charts placement. (In the second test, chart space is smaller and car space (garbage output) takes up too much area in the output. I think it is related to internal config). Please make sure that all chart measurements are correct and camera parameters are accurate. 

Btw, are you working with TI FAE?

Erick Narvaez In the 3D SRV output George shared, we can see garbage data from front and rear cameras. There artifacts look weird.  Where do you think they are from? 

George,

We will need to study the algorithm, currently I don't have any suggestions to remove these artifacts. At a first glance it seems as a result of camera position, but hopefully it can be tuned to avoid this.

Regards,

Erick

Dear Erick Narvaez,

3d_calibration_tool seems very complicated at first glance, but after operating it once, I found that there are very few places that can be adjusted.
I have two examples:
1. I expected that increasing the focal length would avoid the problem of seeing the license plate. But this only works with "Test Lens Correction".
In "Test Surround Calibration", the YUV of "Input images" is still used to stitch the Surround View.
2. I want to adjust the size of the bottom of the Surround View bowl, but I can't find a place to adjust it.
In addition, is the algorithm for Surround View included in ti-processor-sdk-rtos-j721e-evm-09_00_00_02?
Or in Git Hub? Can you tell me where I can download the source code?

Best regard.
George Lin

George,

george lin said:

2. I want to adjust the size of the bottom of the Surround View bowl, but I can't find a place to adjust it.
In addition, is the algorithm for Surround View included in ti-processor-sdk-rtos-j721e-evm-09_00_00_02?
Or in Git Hub? Can you tell me where I can download the source code?

The source code is part of the vision_apps project, you can find the SRV kernel here:

/home/a0226667/sdk/ti-processor-sdk-rtos-j721e-evm-09_00_00_02/vision_apps/kernels/srv/gpu/3dsrv

You can also find the different apps here:

/home/a0226667/sdk/ti-processor-sdk-rtos-j721e-evm-09_00_00_02/vision_apps/apps/srv_demos

We are working on better documenting this, but for now you can take a look at the source code there.

Regards,

Erick

george lin said:

1. I expected that increasing the focal length would avoid the problem of seeing the license plate. But this only works with "Test Lens Correction".
In "Test Surround Calibration", the YUV of "Input images" is still used to stitch the Surround View

Camera parameters including the focal length and distortion parameter should be accurate for SRV calibration. There could be another cause for this artifact, but I think incorrect camera parameters could be a root cause of this artifact. 

Best regards,

Do-Kyoung

Hello George,

There hasn't been no further discussion for the last 2 months. Can we close this thread? For further question, you can reopen it or post a new question.

Best regards,

Do-Kyoung