NFLX CTC¶

Metrics¶

--nflx_ctc v1.0 registers the metrics below. The models are the 4K VMAF models, so the preset is meant for 3840x2160 content.

Metric	Registered as	Options set by the preset
VMAF	model `vmaf_4k_v0.6.1` (output `vmaf`)	none
VMAF NEG	model `vmaf_4k_v0.6.1neg` (output `vmaf_neg`)	none
PSNR, APSNR	`psnr`	`enable_chroma=true`, `enable_apsnr=true`
SSIM	`float_ssim`	`enable_db=true`, `clip_db=true`
CAMBI	`cambi`	none

Usage¶

Basic usage of the tool is described in the vmaf README. Use the versioned --nflx_ctc presets to register and configure all metrics according to the NFLX CTC. Basic usage is as follows:

./build/tools/vmaf \
    --reference reference.y4m \
    --distorted distorted.y4m \
    --nflx_ctc v1.0 \
    --json \
    --output output.json

There are also a few optional command-line settings you may find useful.

Use --threads to set the thread count to be used for multi-threaded computation. This will decrease the overall latency.

Output¶

The preset is intended for the JSON log (--json), which provides per-frame metrics, pooled metrics and aggregate metrics.

NFLX CTC Version History¶

v1.0: --nflx_ctc v1.0
2023-01-01
Initial CTC release