Image Artifacts in 12MP Capture with i.MX8MP GStreamer Pipeline

[malik_cisse]

Hello,

I'm developing a Qt application for the i.MX8MP targeting a 12MP image capture device and encountering image artifacts in the captured PNG images.

Hardware/Software Environment:

• SoC: NXP i.MX8MP
• Camera: 12MP sensor via MIPI CSI-2 (CSI1)
• Framework: Qt with GStreamer
• Capture resolution: 4048x3040

GStreamer Pipeline:

c

descr = g_strdup_printf("v4l2src name=video_source "
                        "device=/dev/video-isp-csi1 "
                        "io-mode=dmabuf ! "
                        "video/x-raw, width=4048,height=3040 ! tee name=t "
                        "t. ! queue max-size-buffers=1 leaky=downstream ! imxvideoconvert_g2d "
                        "name=g2d rotation=3 ! video/x-raw, width=480, height=800 ! appsink "
                        "name=app_sink_live max-buffers=1 drop=True "
                        "t. ! queue ! appsink name=app_sink_snapshot max-buffers=1 drop=True");

Issue: The captured PNG images frequently contain visual artifacts (see attached image). The artifacts appear as corrupted regions or visual distortions in the final image.

Observations:

• MIPI CSI debug logs indicate the CSI signal appears to be stable and correct
• The issue occurs intermittently but frequently enough to be problematic
• Both the live preview path (with rotation and scaling) and snapshot path are affected

Questions:

1. Could this be a buffer synchronization issue between the ISP and the downstream elements?
2. Are there recommended buffer settings or pipeline configurations for high-resolution capture on i.MX8MP?
3. Could the dmabuf io-mode be causing memory coherency issues?
4. Are there any known issues with the ISP driver at this resolution?

Any guidance would be greatly appreciated!

Image: