How to get Monochrome video in STM32N6570-DK board using MB1854B camera

[athern27]

Hi everyone,

I am trying to capture monochrome video using the MB1854B camera module on the STM32N6570-DK board. I am following this tutorial .

My task is to obtain monochrome video at a resolution of 320 × 320 pixels at 60fps

Currently, I am able to capture RGB video at 2592 × 1944 pixels. After checking the imx335.c file, I found only one available resolution (2592 × 1944) at 30fps and a pixel format set to IMX335_RAW_RGGB10.

Is there any way to obtain my desired image resolution without any processing, just by changing register values? If so, where can I find those values? I was able to find the datasheet for the IMX335LQN, in which it was written that it can work at 60fps but it did not contain any details about the registers.

[VABRI]

Dear @athern27,

STM32N6 embedde a new camera pipeline called DCMIPP.

the DCMIPP embedded an ISP to support Rawbayer sensor such as the IMX335.

That's why the IMX335 driver output a RAW10 pixel format that need then to be converted using the ISP of the DCMIPP.

 

In the example you mention, the application is using the ISP Midleware to control the ISP to have RGB output preview. In you case, you want to have a monochrome output, you need to change the configuration of the DCMIPP pixel packer into DCMIPP_PIXEL_PACKER_FORMAT_MONO_Y8_G8_1.

pPipeConf.PixelPackerFormat = DCMIPP_PIXEL_PACKER_FORMAT_RGB565_1;

 

Regarding the fps of the IMX335 sensor, you need to update the IMX335 sensor driver to allow a 60fps configuration but I am sorry to not help further on this point since I don't have knowledge on how to do that.

 

BR

Vincnet

[athern27]

Thank you for replying @VABRI 
I tried changing PixelPackerFormat as you said but it is still not working. 
Earlier I was getting -

in RGB565_1 mode which is nice for RGB images
But after changing to MONO_Y8_G8_1 I am getting - 

 

So this is not working as intended.

Kindly help

[VABRI]

Dear @athern27,

The monochrome picture is 1 bytes per pixel and the preview size is 800x480.

The pitch must be updated as follow:

pPipeConf.PixelPackerFormat = DCMIPP_PIXEL_PACKER_FORMAT_MONO_Y8_G8_1;

 

/* Set Pitch for Main and Ancillary Pipes */

pPipeConf.PixelPipePitch = 800; /* Number of bytes */

 

Further, the display LTDC layer must be updated to warn the display that now the

preview is monochrome. In LCD_Init function replace:

 

pLayerCfg.PixelFormat = LTDC_PIXEL_FORMAT_RGB565;

by

pLayerCfg.PixelFormat = LTDC_PIXEL_FORMAT_L8;

 

Preview should be now monochrome.

 

Vincent