Clarify the difference between imaging and gift about imaging HOT 1 CLOSED

I want to keep the imaging package lightweight and simple. It has smaller API that provides basic image manipulations and a few helper functions like Open and Save. Note the return type of all the manipulation functions - *image.NRGBA. It's a 8 bit per channel image type. In fact any image type is first converted to NRGBA type, then direct pixel data access is used during processing. So if you need basic image manipulations and you don't need extra quality then imaging is a good choice.

The gift package is more apropriate for advanced image processing. It provides more functionality
like convolution filters, color adjustments, conversion to linear colorspace and back to sRGB and so on. I plan adding more filters in the future. The main ideas behind the gift package were to allow using different output image types and to provide easy-to-use API for chaining processing steps together. Here is the signature of core function of the gift package, that applies filters to the src image and outputs the result to the dst image:

func (g *GIFT) Draw(dst draw.Image, src image.Image)

Any image type that implements draw.Image interface can be used in place of dst. For example, 16 bit/channel image (*image.NRGBA64), which is useful for processing high-quality images.

from imaging.