HDR Video Evaluation Framework (Python)

A Python port of the HDR Video Evaluation Framework, originally developed in MATLAB during PhD research at the University of Warwick.

Overview

This framework provides a complete pipeline for evaluating HDR (High Dynamic Range) video compression methods. It supports multiple HDR transfer-function methods, codec integration (x264/x265), and a comprehensive set of perceptual quality metrics.

Features

• Multiple HDR methods: PQ (ITU-R BT.2100), HLG (Hybrid Log-Gamma), HDRV, Fraunhofer, Gamma, GoHDR, HDR-JPEG, HDR-MPEG, PQ-IPT, Rate-Distortion
• Codec support: x264, x265 via ffmpeg
• Quality metrics: PSNR, Log-PSNR, SSIM, PU2-PSNR, PU2-SSIM, Weber RMSE, HDR-VDP
• CLI-driven: Three top-level commands for encode, decode, and evaluate
• Config-file or flag driven: Use YAML config files or pass flags directly

Installation

Requires Python 3.12+ and Poetry.

git clone https://github.com/ratnajitmukherjee/hdr-evaluation-framework-python
cd hdr-evaluation-framework-python
poetry install

External encoders (x264, x265, ffmpeg) must be installed separately and available on PATH.

Usage

Encode HDR frames to a compressed bitstream

# Using a config file
hdr-encode --config configs/example_encode.yaml

# Using CLI flags directly
hdr-encode --input /path/to/exr_frames --method pq --output /path/to/output --qp 22

Decode a bitstream back to HDR frames

hdr-decode --config configs/example_decode.yaml

# Or with flags
hdr-decode --input output.265 --aux /path/to/aux --method pq --output /path/to/decoded

Evaluate quality metrics

hdr-evaluate --config configs/example_evaluate.yaml

# Or with flags
hdr-evaluate --original /path/to/original --decoded /path/to/decoded --output results/

Results are printed to the terminal, saved as CSV, and plotted as PNG figures.

Project Structure

src/hdr_framework/
├── cli/               # argparse entry points (encode, decode, evaluate)
├── methods/           # HDR transfer-function methods (one subpackage each)
│   ├── base.py        # Abstract base class
│   ├── pq/
│   ├── bbc_hlg/
│   └── ...
├── metrics/           # Quality metric implementations
├── encoders/          # x264/x265/ffmpeg subprocess wrappers
├── util/              # Shared utilities (luminance, CSF, image I/O)
├── space_transform/   # Colour space conversions (sRGB↔XYZ, YUV, LUV, IPT)
└── results/           # Matplotlib plotting and CSV export

License

BSD 3-Clause License. Copyright 2018–2025, Ratnajit Mukherjee.