COMPARE.md

More about Backends

Backend	About
Waifu2x Caffe	Waifu2x Caffe does great with Anime and Manga style images. Both the Image output quality and the Alpha quality are top-notch, on the appropriate image type.
Waifu2x Vulkan	Waifu2x Vulkan approaches the quality of Caffe, while slashing the computational and memory requirements. The image quality is good, but the Alpha handling can be a little fuzzy around the edges (can be defringed to great effect.)
RealSR Vulkan	RealSR's image output is great for more realistic images. The Alpha can be a little dark around the edges, but the detail produced on images is fantastic.
SRMD Vulkan	SRMD excels at upscaling poor-quality material. Great for reworking a bad upscale, and also good for upscaling realistic images.
Waifu2x CPP	Waifu2x CPP's output is visually close to Caffe's (if, a little muddier), but is quite fast with low requirements. It does poorly on images with Alpha (but the results are acceptable with defringing turned on and calibrated).
Anime4K CPP	Anime4K CPP is the fastest of the supported backends. It has a high range of input settings, and is intended for Anime or Manga style images. Visual quality has quite a bit of variance, but can look quite good once the settings are dialed in.

Reference Images:

Images for comparison. The source is not mine, and these images exist purely for edification.

Source

Caffe 4x	Waifu2x Vulkan 4x

Waifu2x CPP 4x	Anime4K 4x

RealSR 4x	SRMD 4x

ESRGAN (4xBox)	ESRGAN (4x_FireAlpha)