TDA4VM: Color change problem

Hi,

Both of the images look wrong to me.

Could you please share the raw and yuv images?

Hello,

Here are the raw and yuv images: raw and yuv images.zip

And I found the integration time value is 0x64 (value of sensor register 3012) when the color of image is abnormal, while this value is 0x4 in the case of  the color of image is normal under the same scene. When I change the value of the integration time of the abnormal color image to 0x4 (write register 3012), the image color becomes normal. It looks like unstable AE control cause the change of image color.

Could you please help me analyze this problem?

Hi Zhili,

Yes, the exposure is too high with 0x64.

AR0820 support in PSDK is tuned and tested with the Leopard Imaging camera with fisheye lens.

What camera/lens module do you use and have you made any changes to PSDK for AR0820?

Best,
Gang

Hi Gang,

The module I use is developed by ourselves, and there are three lenses with fov of 30°/60°/120°. Do different lenses need to be calibrated accordingly?

We added the Set_AwbParams function in AR0820 driver according to AR0233, please see https://e2e.ti.com/support/processors-group/processors/f/processors-forum/1063800/tda4vm-absence-of-0820-setawb-code?version=2.5.40002.154&platform=win.

And we applied two patches for AE and AWB respectively, see https://e2e.ti.com/support/processors-group/processors/f/processors-forum/1065532/tda4vm-problem-of-ae-control-algorithm-in-sdk-7-03 and https://e2e.ti.com/support/processors-group/processors/f/processors-forum/1072148/tda4vm-how-to-apply-pre-gain-awb-in-tda4-with-0820-sensor. Now the AWB gains set in the sensor.

Hi Zhili,

Yes, different lenses may require different calibration.
The most important differences are lens aperture (may affect exposure) and lens color response (affects AWB and color correction).

Do you have any local TI FAE supporting your work?

Best,
Gang

Hi Gang，

I don't have any local TI FAE supporting my work.

Could you please share me the method and tool for lens calibration?

Regards,

Zhili

Hi Zhili,

We have TDA4 ISP (VPAC) documents and tuning tool under NDA which cannot be shared publicly.

Could you please contact your local TI sales representative?

Best,
Gang

Hi Gang,

Can you tell me the NDA status you mentioned?

(PS: I am wondering where is your workplace, if you are in China, can we use more convenient communication methods such as phone calls or WeChat?)

Regards,

Zhili.

Hi Gang,

Thanks for your help very much. 

I would like to know that will they contact me by email? And how long will I wait?

Regards,

Zhili

Hi Zhili,

I don't know the arrangement details in TI China.
We have FAEs in Beijing supporting HiRain.
They should be able to verify HiRain's NDA status and request access to tuning tool for you.

Best,
Gang

Hi Gang,

I get it. Thank you very much.

Regards,

Zhili