Add "8x_NMKD-Typescale model" (best to upscale text)

[Disonantemus]

I want to use the model 8x_NMKD-Typescale, because is the best to upscale text.

I was able to convert and use many ESRGAN models to NCNN using ChaiNNer.

I was able to convert 8x_NMKD-Typescale to NCNN in the same way, but Real-ESRGAN-ncnn-vulkan doesn't support 8x scaling, I did This Issue there, but project has no activity (since 3 years).

I'm no programmer, and I don't know how to do this.
Maybe I'm wrong asking for this here, but I don't know where else to ask.

Thanks in advance,
Nice project!

[TransparentLC]

Both Real-ESRGAN-ncnn-vulkan and upscayl-ncnn only support 2-4x for now, maybe I could have a try of adding 8x by some copy-and-pasting in realesrgan.{h,cpp} and then make a custom build by myself?

I'll try it when I have enough spare time. It should help if you can attach the converted NCNN model.

[TransparentLC]

Can you attach some converted 8x (or even 16x?) NCNN model (bin and param file) for me to do some testing?

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Take some note about upscayl-ncnn's code related to scaling at here.

There exists auto detection for 8x and 16x in upscayl-ncnn. But I don't know why it is disabled in Windows.

https://github.com/upscayl/upscayl-ncnn/blob/8f8babf3ec9a2eefe92892ccdbbb55afc0243284/src/main.cpp#L1023-L1089

Why use seperate layers for alpha channel scaling for 2x, 3x and 4x...?

https://github.com/upscayl/upscayl-ncnn/blob/8f8babf3ec9a2eefe92892ccdbbb55afc0243284/src/realesrgan.cpp#L166-L202
https://github.com/upscayl/upscayl-ncnn/blob/8f8babf3ec9a2eefe92892ccdbbb55afc0243284/src/realesrgan.cpp#L376-L395