Enum VideoCodec 

pub enum VideoCodec {
    H264,
    OpenH264,
    H265,
    Kvazaar,
    Vp8,
    Vp9,
    Av1,
    Svtav1,
    Mpeg4,
}

Which software encoder to open. Whatever’s picked, SwEncoder::new fails with SwEncoderError::CodecNotFound (not a panic) if the linked ffmpeg build doesn’t actually have it — this crate never vendors any of these, it’s whatever the local ffmpeg install was built with (check with ffmpeg -encoders).

GPL-licensed encoders need an ffmpeg build compiled with --enable-gpl (separate from — and unlike — FFmpeg’s own native h264/hevc decoders, which SwDecoder already uses and which carry no such requirement; GPL only enters the picture on the encode side, through these specific libraries): VideoCodec::H264 and VideoCodec::H265 are GPL. Every other variant here is a permissively-licensed (BSD/similar) alternative that needs no special build flag beyond being enabled at all.

Variants

H264

libx264 — H.264. GPL.

OpenH264

libopenh264 — H.264, Cisco’s BSD-2-Clause encoder (Cisco covers H.264 patent royalties for binary redistributions of it). The non-GPL alternative to VideoCodec::H264.

H265

libx265 — H.265/HEVC. GPL.

Kvazaar

libkvazaar — H.265/HEVC, BSD-2-Clause. The non-GPL alternative to VideoCodec::H265.

Vp8

libvpx — VP8, BSD-3-Clause.

Vp9

libvpx-vp9 — VP9, BSD-3-Clause (same libvpx project as VideoCodec::Vp8, different encoder name).

Av1

libaom-av1 — AV1’s reference encoder, BSD-2-Clause. Most broadly compatible AV1 output, but much slower than VideoCodec::Svtav1 — prefer that one unless you specifically need libaom’s own encoding behavior.

Svtav1

libsvtav1 — AV1 via Intel’s SVT-AV1, BSD-2-Clause-Patent. Far faster than VideoCodec::Av1 (libaom-av1) at a given quality target — the practical default for real-time AV1 encoding.

Mpeg4

mpeg4 — MPEG-4 Part 2, and the only encoder here that is FFmpeg’s own rather than a library it was linked against.

Which is the whole reason it is offered. Every variant above needs its library to have been enabled at build time, and an FFmpeg with none of them cannot encode video at all through this element. This one is in every build there is.

It is also the only always-present encoder that will emit B-frames (see SwEncoderOptions::max_b_frames) — libopenh264 emits none whatever it is asked for, and the H.264 encoders that would are the GPL ones. That makes it what a test reaches for when what it is testing is reordering.

Not a codec to choose for output anyone has to play: it predates H.264 and compresses far worse at the same quality.

Trait Implementations

impl Clone for VideoCodec

fn clone(&self) -> VideoCodec

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Copy for VideoCodec

impl Debug for VideoCodec

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Eq for VideoCodec

impl PartialEq for VideoCodec

fn eq(&self, other: &VideoCodec) -> bool

Equality operator ==.

fn ne(&self, other: &Rhs) -> bool

Inequality operator !=.

impl StructuralPartialEq for VideoCodec