AV1 or HEVC: tune for the frame
Use short encode sweeps and perceptual metrics to choose settings without losing sight of the source.
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Define the playback target
Start with the devices that need to play the release. Check container, bit depth, subtitle handling, and hardware decoding support using a short sample.
Build a small CRF sweep
Choose a fixed preset and vary the quality control. Keep source frames, color conversions, and filter settings identical between tests.
AV1 test command
SvtAv1EncApp -i sample.y4m -b sample.ivf --crf 22 --preset 4HEVC test command
x265 --input sample.y4m --y4m --crf 17 --preset slow --profile main10 --output sample.hevcCRF values are encoder-specific. AV1 CRF 22 and x265 CRF 22 do not imply equal fidelity or equal file size.
Read metrics with their limits
SSIMULACRA 2 and VMAF can help identify promising candidates. PSNR reports pixel error, while Butteraugli measures perceptual difference. Lower Butteraugli is better. FPS measures encoding speed rather than image fidelity.
Metrics are a screening tool. Always inspect fine lineart, intentional grain, and difficult motion directly.
Choose and document the result
Use the rate–distortion notebook to explore how bitrate and CRF change the view. Its sample values are illustrative and cannot establish an encoder ranking.
Record the exact encoder build, CPU, preset, test clip, filter chain, and metric implementation with your own measurements. Include the final command and playback notes in the release notebook.