AV1 Encoding with libsvtav1 on Qencode

Description

The libsvtav1 encoder (SVT-AV1) is an AV1 implementation tuned for both compression efficiency and parallel performance. This guide covers the preset scale from 0 to 13 and its speed-versus-efficiency trade-off, CRF selection in the 20-40 range, MP4 versus WebM output, and advanced controls including tune, aq_mode, film_grain, fast_decode, enable_dlf, enable_restoration, hierarchical_levels and pred_struct. It gives concrete starting points: preset 3 for archival, preset 8 for fast turnaround, preset 5 with CRF 30-35 for web streaming, and fast_decode when targeting low-power devices such as set-top boxes and budget phones. On why AV1 at all: roughly 30-40% bitrate savings versus H.264 and 20-30% versus HEVC or VP9 at equivalent quality, royalty-free under the Alliance for Open Media, with decode support in Chrome, Firefox and Edge.

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