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May 26, 2020 16:55
May 26, 2020 16:55
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RealSR ncnn Vulkan

CI download

ncnn implementation of Real-World Super-Resolution via Kernel Estimation and Noise Injection super resolution.

realsr-ncnn-vulkan uses ncnn project as the universal neural network inference framework.


Download Windows/Linux/MacOS Executable for Intel/AMD/Nvidia GPU

This package includes all the binaries and models required. It is portable, so no CUDA or Caffe runtime environment is needed :)

About RealSR

Real-World Super-Resolution via Kernel Estimation and Noise Injection (CVPRW 2020)

Xiaozhong Ji, Yun Cao, Ying Tai, Chengjie Wang, Jilin Li, and Feiyue Huang

Tencent YouTu Lab

Our solution is the winner of CVPR NTIRE 2020 Challenge on Real-World Super-Resolution in both tracks.


Example Command

realsr-ncnn-vulkan.exe -i input.jpg -o output.png -s 4

Full Usages

Usage: realsr-ncnn-vulkan -i infile -o outfile [options]...

  -h                   show this help
  -v                   verbose output
  -i input-path        input image path (jpg/png/webp) or directory
  -o output-path       output image path (jpg/png/webp) or directory
  -s scale             upscale ratio (4, default=4)
  -t tile-size         tile size (>=32/0=auto, default=0) can be 0,0,0 for multi-gpu
  -m model-path        realsr model path (default=models-DF2K_JPEG)
  -g gpu-id            gpu device to use (-1=cpu, default=0) can be 0,1,2 for multi-gpu
  -j load:proc:save    thread count for load/proc/save (default=1:2:2) can be 1:2,2,2:2 for multi-gpu
  -x                   enable tta mode
  -f format            output image format (jpg/png/webp, default=ext/png)
  • input-path and output-path accept either file path or directory path
  • scale = scale level, 4 = upscale 4x
  • tile-size = tile size, use smaller value to reduce GPU memory usage, default selects automatically
  • load:proc:save = thread count for the three stages (image decoding + realsr upscaling + image encoding), using larger values may increase GPU usage and consume more GPU memory. You can tune this configuration with "4:4:4" for many small-size images, and "2:2:2" for large-size images. The default setting usually works fine for most situations. If you find that your GPU is hungry, try increasing thread count to achieve faster processing.
  • format = the format of the image to be output, png is better supported, however webp generally yields smaller file sizes, both are losslessly encoded

If you encounter crash or error, try to upgrade your GPU driver

Build from Source

  1. Download and setup the Vulkan SDK from
  • For Linux distributions, you can either get the essential build requirements from package manager
dnf install vulkan-headers vulkan-loader-devel
apt-get install libvulkan-dev
pacman -S vulkan-headers vulkan-icd-loader
  1. Clone this project with all submodules
git clone
cd realsr-ncnn-vulkan
git submodule update --init --recursive
  1. Build with CMake
  • You can pass -DUSE_STATIC_MOLTENVK=ON option to avoid linking the vulkan loader library on MacOS
mkdir build
cd build
cmake ../src
cmake --build . -j 4

Sample Images

Original Image


Upscale 4x with ImageMagick Lanczo4 Filter

convert origin.jpg -resize 400% output.png


Upscale 4x with srmd scale=4 noise=-1

srmd-ncnn-vulkan.exe -i origin.jpg -o 4x.png -s 4 -n -1


Upscale 4x with realsr model=DF2K scale=4 tta=1

realsr-ncnn-vulkan.exe -i origin.jpg -o output.png -s 4 -x -m models-DF2K


Original RealSR Project

Other Open-Source Code Used