The PSNR definition provided by wikipedia is often quoted in discussions regarding PSNR and other similarity metrics.
Essentially the PSNR calculation has two components: the mean squared error and the "maximum possible pixel value of the image" (as per the wikipedia definition).
For arrays (or images) containing 8 bit integer values (e.g. .bmp images), the maximum possible pixel value of the image is 255, since this is the largest 8-bit integer possible.
For arrays (or images) with floating point values (e.g. some .tiff images) the wikipedia definition suggests "the maximum possible pixel value of the image" = 1. Why is this value of 1 chosen?
This would make sense for data that has been min/max normalised, such that the range of the data is 1. However generally, arrays containing floats would not be normalised.
Any insight into what is the generally accepted, correct value for "the maximum possible pixel value of the image" in calculating the PSNR would be appreciated.