waveform80 / picamera

A pure Python interface to the Raspberry Pi camera module
https://picamera.readthedocs.io/
BSD 3-Clause "New" or "Revised" License
1.57k stars 355 forks source link

How to turn off GPU Color Processing #635

Open JosepRelat opened 4 years ago

JosepRelat commented 4 years ago

Hi,

I'm trying to use PiCamera to reliably read color levels from paper samples. For this purposes, I need to know that the RGB channels between different images is constant (otherwise the data analysis turns useless). I take care that light levels and environment are in a controlled conditions.

I have explored the option of using the Bayer layer. This does the job, but CPU de-mosaicing it is very long for my application.

I have also explored using the unencoded RGB capture. I have turned off exposure mode and awb_mode. I control iso and other parameters. However, I'm unsure of what does brightness do the image. Could anyone help me understand how to 'turn it off' or at least understand how it changes the colors of the sample. With that working, all my problems would be gone :D

KR,

Josep