Frequent Horizontal Lines in IMX214 Sensor (SKU: MSU-M0024 ).

[Jeremy Frederick]

I've been using the IMX214 4k High-Resolution sensor for the past few days and I've noticed some fairly severe horizontal lines crowding the frame in dark environments. Any thoughts as to why this is? Is there anything I can do in the camera settings to limit this?

VOXL 2 , SDK 1.3

Horizontal Lines in IMX214 Modal AI Camera

Horizontal Lines in IMX214 Modal AI Camera

Vimeo (vimeo.com)

[Alex Kushleyev]

@Jeremy-Frederick , I definitely see the issue in the video.

Sometimes it is possible for another camera to interfere with IMX214 (add noise on power). In dark scenarios, the analog gain increases, which generally increases the pixel noise, but this is not a normal behavior to see such stripes.

Can you please describe what cameras you have connected to VOXL2 and where they are connected (which conector J6,7,8 upper / lower).

Alex

[Jeremy Frederick]

@Alex-Kushleyev We have IMX214 connected to J7 Upper through the m0084 cable. Alongside it is a ARR0144 Tracking Camera connected to J7 Lower.

[Alex Kushleyev]

@Jeremy-Frederick , thanks for sharing. Is AR0144 running at 30 fps?

If you can share your voxl-camera-server.conf file, that would be helpful - i can test it directly.

I believe the workaround for this issue is to connect the AR0144 camera to another Jx port - this will help isolate the ripple on the power rail coming from AR0144 camera.

I will confirm this after testing and hopefully this is possible to do in your hardware configuration. There is no software fix for this issue, other than keeping the gain lower, but you kind of have to raise the gain to see things in the dark..

Alex

[Jeremy Frederick]

@Alex-Kushleyev

{
"version": 0.1,
"fsync_en": false,
"fsync_gpio": 109,
"cameras": [{
"type": "ar0144",
"name": "tracking",
"enabled": true,
"camera_id": 0,
"fps": 30,
"en_rotate": false,
"en_preview": true,
"preview_width": 1280,
"preview_height": 800,
"en_raw_preview": true,
"ae_mode": "lme_msv",
"ae_desired_msv": 60,
"exposure_min_us": 20,
"exposure_max_us": 33000,
"gain_min": 54,
"gain_max": 8000,
"exposure_soft_min_us": 5000,
"ae_filter_alpha": 0.600000023841858,
"ae_ignore_fraction": 0.20000000298023224,
"ae_slope": 0.05000000074505806,
"ae_exposure_period": 1,
"ae_gain_period": 1
}, {
"type": "imx214",
"name": "hires",
"enabled": true,
"camera_id": 1,
"fps": 30,
"en_preview": false,
"preview_width": 640,
"preview_height": 480,
"en_raw_preview": false,
"en_small_video": true,
"small_video_width": 1024,
"small_video_height": 768,
"small_venc_mode": "h265",
"small_venc_br_ctrl": "cqp",
"small_venc_Qfixed": 30,
"small_venc_Qmin": 15,
"small_venc_Qmax": 40,
"small_venc_nPframes": 9,
"small_venc_mbps": 2,
"en_large_video": true,
"large_video_width": 4208,
"large_video_height": 3120,
"large_venc_mode": "h265",
"large_venc_br_ctrl": "cqp",
"large_venc_Qfixed": 38,
"large_venc_Qmin": 15,
"large_venc_Qmax": 50,
"large_venc_nPframes": 29,
"large_venc_mbps": 30,
"en_snapshot": true,
"en_snapshot_width": 4208,
"en_snapshot_height": 3120,
"exif_focal_length": 0,
"exif_focal_length_in_35mm_format": 0,
"exif_fnumber": 0,
"ae_mode": "isp"
}]
}

[Alex Kushleyev]

@Jeremy-Frederick , thank you! i will try to set this up this week.

Alex

[Alex Kushleyev]

I was able to replicate your issue and also confirmed that the issue goes away if I move the AR0144 camera from the M0084 cable (connected to J7L) to J6L using M0076 interposer.

I believe the issue is related to potentially insufficient decoupling capacitance in the IMX214 camera, so running it on the same flex with another camera causes noisy pixels.

I hope you can work around the issue by moving the AR0144 camera to another port.

Sorry about that!

Alex