My aim is to use the newer THX colouring (on the DC/Face LD and GOUT DVD) as a reference to automatically correct the pre-THX colours. Here is the same shot from the GOUT DVD:
Previous threads discussing colour matching:
Here Laserman posted a scientific paper describing a method of automatic colur grading using N-dimensional probability density function transfer. As far as I know this has not been implemented into anything useful yet, and the mathematics behind the method is a little over my head.
Here superrune described a method of correcting the 2004 DVD version by combining the luma information from the 2004 DVD with the chroma information from the GOUT DVD. The drawback with this method that the two sources need to be lined up in every shot, which involves quite a lot of manual work.
Near the end of the second thread, someone mentioned the AviSynth filter ColourLike. This is effectively a 1D PDF transfer, as described in the paper linked in the first thread, carried out separately on each channel. (I confirmed this by following that method, and obtained results almost identical to ColourLike). The results look like this:
A bit grainy and washed out, although apparently better results can be achieved using RGB colourspace instead of YUV (would prefer to stick with YUV, though).
Here's my attempt using a similar "semi-automatic" method, but approximating the lookup values to a smooth curve to reduce the graininess of the image. The colours aren't as accurate, though:
Anyone know of any other methods that could be implemented into AviSynth?