Comment by orbital-decay
2 hours ago
That's exactly what I'm talking about, how do you imagine that working? Metadata is not compatible by design, because processing pipelines are all subtly different and your result will always look different in your editor. Trying to match some basic parameters with the JPEG is possible and some RAW software can do that, but the result is going to be subtly different for the same reason.
Search over all values of all parameters and choose the ones the minimise the mean square error of pixel values.
Obviously that will be slow, so probably do some kind of gradient descent, or perhaps depending on what the parameters are there may be a closed-form solution, I don't know.
Yes the result will be subtly different but it's just a starting point.
Isn't that what the "auto" button does, and then you can tweak from there?
I've never had to write such software but in my imagination there is the sensor data, potentially from several exposures, and some static data about the camera, and a list of edits and parameters that the photo app is using to produce the in-camera JPEG. And I just want a way to intervene in that list of edits and parameters to produce my own result. There must be SOME way to do this otherwise how do I edit raws from my real camera? The starting point for camera raw in my photo editor always looks great if the file came from my camera, and always looks ghastly if it came from my mobile.