Hallo james, Hallo njk, thanks for your responses.
It was also my first thought, that it is dropping a bit somewhere. But if that would be the case I don't see, why the peak would not be at 127 but is between 128 and 130.
It starts to get even wilder...
When I insert a full green test pattern with a defined pixel value like 2000 (aka 125 in 8bit) for green1 and 4000 (aka 250 in 8bit) for green 2. I get peeks at 149, 154 and 157. And a standard bar chart does not show black at all and the peak are non-linear shifted. I added the pictures and histograms at the end of the post.
It can absolutely be post-processing. But it can not be a wrong type being used. Since I use the same python code on the PNGs to generate the histograms.
Could you confirm that the media controller setting are correct? When comparing it to Jean-Michel description in https://lwn.net/Articles/881164/ I noticed that I have to call d3 not d0 like he does, but chalked that up to not important.:
It was also my first thought, that it is dropping a bit somewhere. But if that would be the case I don't see, why the peak would not be at 127 but is between 128 and 130.
It starts to get even wilder...
When I insert a full green test pattern with a defined pixel value like 2000 (aka 125 in 8bit) for green1 and 4000 (aka 250 in 8bit) for green 2. I get peeks at 149, 154 and 157. And a standard bar chart does not show black at all and the peak are non-linear shifted. I added the pictures and histograms at the end of the post.
It can absolutely be post-processing. But it can not be a wrong type being used. Since I use the same python code on the PNGs to generate the histograms.
Could you confirm that the media controller setting are correct? When comparing it to Jean-Michel description in https://lwn.net/Articles/881164/ I noticed that I have to call d3 not d0 like he does, but chalked that up to not important.:
Code:
media-ctl -d3 -pMedia controller API version 6.1.77Media device information------------------------driver unicammodel unicamserial bus info platform:fe801000.csihw revision 0x0driver version 6.1.77Device topology- entity 1: mfc520a 10-0010 (1 pad, 1 link) type V4L2 subdev subtype Sensor flags 0 device node name /dev/v4l-subdev0 pad0: Source [fmt:SGRBG12_1X12/1820x940 field:none colorspace:raw crop.bounds:(4,4)/1820x940 crop:(4,4)/1820x940] -> "unicam-image":0 [ENABLED,IMMUTABLE]- entity 3: unicam-image (1 pad, 1 link) type Node subtype V4L flags 1 device node name /dev/video0 pad0: Sink <- "mfc520a 10-0010":0 [ENABLED,IMMUTABLE]- Image may be NSFW.
Clik here to view.
- Image may be NSFW.
Clik here to view.
Statistics: Posted by 1820x940 — Thu May 09, 2024 9:19 pm
