4 ms·

As I understand it, colorimeter expect the display to output a particular colour or shade and measure it precisely. You probably couldn't run colorimeter softwa

As I understand it, colorimeter expect the display to output a particular colour or shade and measure it precisely. You probably couldn't run colorimeter software on a GBA, but you could write homebrew that let the user manually cycle to the correct patterns at the right times. Some issues would be: - There's at least three models of GBA display: the original front-lit display, the GBA SP back/front-lit display, and the later GBA SP backlit-only display, and they probably all have different profiles - It's probably not possible to use a colorimeter on the original front-lit GBA display, because with a colorimeter clamped on top of it, it would always look black - Colour-correction software that works with ICC profiles is typically built for print/still image work, so it expects a single high-resolution image with high-precision output, not a 60fps stream of very-low-resolution images. Maybe it's fast enough to run in real-time, who knows?

rossy 7y ago
Yeah, writing homebrew to get the GBA screen to display whatever a screen displays under a colourimeter, and getting that to work with the actual colourimeter might not be so easy. I think getting a device profile for the frontlit SP would be the most interesting, since I've heard it produces colours more like the original GBA than the backlit one, but maybe a colourimeter designed for backlit PC monitors would have trouble with it. I don't think performance would be an issue though. mpv can do colour management in real time by generating a LUT from the ICC profile and applying it to each frame with GPU shaders.
- MartijnBraam 7y ago
  Most colorimeters also have a projector mode for measuring beamer screens. You can just point the colorimeter to the gba screen bar an angle and shine a high quality light source at it
  - rossy 7y ago
    That's cool. I didn't know that (I've never used one before.) Maybe it would make more sense to do the original GBA then. The SP frontlight has a bit of a blueish tinge to it.
DoctorOetker 7y ago
I think relaying the image with a lens onto the colorimeter should work assuming you modify the game so the hardware displays a full screen equivalent of all possible variations of a single pixel. it might be necessary to switch to a color cube with 3 photodiodes, and perhaps read in with 3 DC-coupled audio channels, or alternatively use an arduino's ADC (I know ...) but with a proper antialiasing filter capacitor for the sample rate used.

rossy 7y ago

Yeah, writing homebrew to get the GBA screen to display whatever a screen displays under a colourimeter, and getting that to work with the actual colourimeter might not be so easy. I think getting a device profile for the frontlit SP would be the most interesting, since I've heard it produces colours more like the original GBA than the backlit one, but maybe a colourimeter designed for backlit PC monitors would have trouble with it. I don't think performance would be an issue though. mpv can do colour management in real time by generating a LUT from the ICC profile and applying it to each frame with GPU shaders.

MartijnBraam 7y ago
Most colorimeters also have a projector mode for measuring beamer screens. You can just point the colorimeter to the gba screen bar an angle and shine a high quality light source at it
- rossy 7y ago
  That's cool. I didn't know that (I've never used one before.) Maybe it would make more sense to do the original GBA then. The SP frontlight has a bit of a blueish tinge to it.

DoctorOetker 7y ago

I think relaying the image with a lens onto the colorimeter should work assuming you modify the game so the hardware displays a full screen equivalent of all possible variations of a single pixel. it might be necessary to switch to a color cube with 3 photodiodes, and perhaps read in with 3 DC-coupled audio channels, or alternatively use an arduino's ADC (I know ...) but with a proper antialiasing filter capacitor for the sample rate used.