TDA4AEN-Q1: NSF4

20250514_NSF4.rar

Hi Taylar,

Do you bypass NSF4 on the H/W?

https://software-dl.ti.com/jacinto7/esd/processor-sdk-rtos-jacinto7/07_03_00_07/exports/docs/tiovx/docs/user_guide/structtivx__vpac__viss__params__t.html#a55a1d8cdcd8997fe45f9b0f752e56979

I see that there is difference in the tuning tool project.

You may also check the app note below for NSF4 tuning section for SDR sensors.

https://www.ti.com/lit/an/sprad86a/sprad86a.pdf?ts=1747264564370&ref_url=https%253A%252F%252Fconfluence.itg.ti.com%252F

Hi Gang Hua,

Thanks for your advise and NSF4 can work normally now. However, the lowlight noise is still obvious even though I set the threshold to match noise level.

Could you recommend other method to reduce noise level in very dark environment. Is there temporal noise filter?

NSF4_20250519.rar

Hi Taylar,

Taylar Huang said:

However, the lowlight noise is still obvious even though I set the threshold to match noise level.

Could you please share the raw image as well?

Taylar Huang said:

Could you recommend other method to reduce noise level in very dark environment. Is there temporal noise filter?

Unfortunately, DA4 VPAC does not include temporal noise filter.
It can only be implemented in DSP S/W on TDA4.

Further reducing noise in very dark environment by VPAC or sensor may require some tradeoffs, e.g., increasing sensor exposure time (lowering frame rate), lower color saturation to reduce color noise, lower output image brightness (hide noise in dark) etc.

NSF4_20250519_raw.rar

Hi Taylar,

Thanks for sharing!

Noise level is quite high in the raw image especially in the blue channel (lighting may be yellowish at very dark conditions).
e.g., at the same location, SNR for R and G is around 2.4x ~ 2.7x, but only 1.6x for B.

One more thing you may try for this extreme condition is to use higher NSF4 thresholds for B and lower ones for R and G.
That may keep a little more details in the image.

Hi Gang Hua,

Do you mean the threshold from four rows correspond with R Gr Gb B? So, I need to adjust it manually?

//noise_thr_y
{
{ 16384, 16384, 16384, 16384, 16384, 16384, 16384, 16384, 16384, 16384, 16384, 16384 },   -> R
{ 16384, 16384, 16384, 16384, 16384, 16384, 16384, 16384, 16384, 16384, 16384, 16384 },   -> Gr
{ 16384, 16384, 16384, 16384, 16384, 16384, 16384, 16384, 16384, 16384, 16384, 16384 },    -> Gb
{ 16384, 16384, 16384, 16384, 16384, 16384, 16384, 16384, 16384, 16384, 16384, 16384 },     -> B