Tinyavif is a proof-of-concept project to test how simple an AV1 encoder can be while still generating spec-compliant, AVIF-format output.
Disclaimer: This is not intended as a serious production encoder, and should not be relied upon as such. However, if you wish to use this project as a starting point to further explore AV1 encoding, please do! We'd love to hear about it!
For more details, please see the accompanying blog post series.
As a proof of concept, tinyavif does not have any formal packaging. Therefore,
to build, download the repository and run cargo build --release. This
generates a statically-linked executable target/release/tinyavif.
Then to run, either copy this executable somewhere and run tinyavif ARGS...,
or combine the two steps as cargo run release -- ARGS... (the -- is
required).
Either way, the basic usage is:
tinyavif <INPUT> [-o <OUTPUT>] [--qindex <QINDEX>]
The input file must be in the Y4M format, and must use 8 bits per pixel with
4:2:0 downsampling (yuv420p format if using ffmpeg for conversion).
The output file can be either a raw AV1 stream (filename ending in .obu) or
an AVIF file (filename ending in .avif).
qindex acts as the quality setting, and ranges from 1 (near-lossless) to 255
(extremely low quality). The default is 35, which should be a decent starting
point for high-quality encodes.
If coming from other AV1 encoders which expect a qp value, start from
qindex = 4 * qp and adjust from there.
Tinyavif does not read colour space information from its input yet. By default it sets all output colour space parameters to "unspecified"; other tools will then make a best guess at the appropriate parameters.
If you want to set specific parameters, these can be set using the
--color-primaries, --transfer-function, and --matrix-coefficients
arguments. Each argument takes a numerical index; see the excellent
Codec Wiki pages on
colorimetry for what these correspond to.
The source code for tinyavif is distributed under the BSD 2-clause license. In addition, tinyavif is subject to the AOMedia Patent License 1.0.