Image Quality Metrics

This library provides Vulkan implementations of SSIM, FSIM, FLIP, PSNR, LPIPS image quality metrics.

Prerequisites

• C++ 20
• Vulkan 1.2+
• VkFFT (only for FSIM)

Binary Usage

Main executable is IQM:

IQM --method METHOD --input INPUT --ref REF [--output OUTPUT]

Arguments:

• --method <METHOD> : selects method to compute, one of SSIM, FSIM, FLIP, PSNR, LPIPS
• --input <INPUT> : path to tested image
• --ref <REF> : path to reference image
• --output <OUTPUT> : path to output image, optional
• -v, --verbose : enables more detailed output
• -c, --colorize : colorize final output
• -h, --help : prints help

Method specific arguments:

PSNR:

• --psnr-variant <VAR> : One of rgb, luma or yuv

FLIP:

• --flip-width <WIDTH> : Width of display in meters
• --flip-res <RES> : Resolution of display in pixels
• --flip-distance <DISTANCE> : Distance to display in meters

Library Usage

Example library usage can be found in /bin/shared/wrappers folder for each implemented method. Simplified it can look like this:

IQM::FLIP flip(device); // init method with `vk::raii::Device`

// populate input structure with Vulkan objects and arguments to method
auto flipInput = IQM::FLIPInput {
    .args = flipArgs,
    ....
};

commandBuffer->begin();
flip.computeMetric(flipInput);
commandBuffer->end();

Compilation

• needs properly configured Vulkan SDK (Tested on Ubuntu 25.04), or packages from system (Arch Linux)
  • in case of bad setup, link errors or missing includes will appear
• for FSIM, git submodule with VkFFT must be fetched
• before C++ compilation compile shaders by ./compile_shaders.sh
• after compilation copy lpips.dat next to executable