8cc7a22b0b
This extensive PR rewrites the internal mixing logic of the driver to use symphonia for parsing and decoding audio data, and rubato to resample audio. Existing logic to decode DCA and Opus formats/data have been reworked as plugins for symphonia. The main benefit is that we no longer need to keep yt-dlp and ffmpeg processes alive, saving a lot of memory and CPU: all decoding can be done in Rust! In exchange, we now need to do a lot of the HTTP handling and resumption ourselves, but this is still a huge net positive. `Input`s have been completely reworked such that all default (non-cached) sources are lazy by default, and are no longer covered by a special-case `Restartable`. These now span a gamut from a `Compose` (lazy), to a live source, to a fully `Parsed` source. As mixing is still sync, this includes adapters for `AsyncRead`/`AsyncSeek`, and HTTP streams. `Track`s have been reworked so that they only contain initialisation state for each track. `TrackHandles` are only created once a `Track`/`Input` has been handed over to the driver, replacing `create_player` and related functions. `TrackHandle::action` now acts on a `View` of (im)mutable state, and can request seeks/readying via `Action`. Per-track event handling has also been improved -- we can now determine and propagate the reason behind individual track errors due to the new backend. Some `TrackHandle` commands (seek etc.) benefit from this, and now use internal callbacks to signal completion. Due to associated PRs on felixmcfelix/songbird from avid testers, this includes general clippy tweaks, API additions, and other repo-wide cleanup. Thanks go out to the below co-authors. Co-authored-by: Gnome! <45660393+GnomedDev@users.noreply.github.com> Co-authored-by: Alakh <36898190+alakhpc@users.noreply.github.com>
Songbird
Songbird is an async, cross-library compatible voice system for Discord, written in Rust. The library offers:
- A standalone gateway frontend compatible with serenity and twilight using the
"gateway"and"[serenity/twilight]-[rustls/native]"features. You can even run driverless, to help manage your lavalink sessions. - A standalone driver for voice calls, via the
"driver"feature. If you can create aConnectionInfousing any other gateway, or language for your bot, then you can run the songbird voice driver. - And, by default, a fully featured voice system featuring events, queues, RT(C)P packet handling, seeking on compatible streams, shared multithreaded audio stream caches, and direct Opus data passthrough from DCA files.
Intents
Songbird's gateway functionality requires you to specify the GUILD_VOICE_STATES intent.
Codec support
Songbird supports all codecs and formats provided by Symphonia (pure-Rust), with Opus support provided by audiopus (an FFI wrapper for libopus).
By default, Songbird will not request any codecs from Symphonia. To change this, in your own project you will need to depend on Symphonia as well.
# Including songbird alone gives you support for Opus via the DCA file format.
[dependencies.songbird]
version = "0.4"
features = ["builtin-queue"]
# To get additional codecs, you *must* add Symphonia yourself.
# This includes the default formats (MKV/WebM, Ogg, Wave) and codecs (FLAC, PCM, Vorbis)...
[dependencies.symphonia]
# version = "0.5"
features = ["aac", "mp3", "isomp4", "alac"] # ...as well as any extras you need!
# **NOTE**: For now, please use this fork in pre-releases for a key fix to
# seeking on streamed MKV/WebM files.
git = "https://github.com/FelixMcFelix/Symphonia"
branch = "songbird-fixes"
Dependencies
Songbird needs a few system dependencies before you can use it.
- Opus - Audio codec that Discord uses.
audiopus will use installed libopus binaries if available via pkgconf on Linux/MacOS, otherwise you will need to install cmake to build opus from source.
This is always the case on Windows.
For Unix systems, you can install the library with
apt install libopus-devon Ubuntu orpacman -S opuson Arch Linux. If you do not have it installed it will be built for you. However, you will need a C compiler and the GNU autotools installed. Again, these can be installed withapt install build-essential autoconf automake libtool m4on Ubuntu orpacman -S base-develon Arch Linux.
This is a required dependency. Songbird cannot work without it.
- yt-dlp / youtube-dl / (similar forks) - Audio/Video download tool.
yt-dlp can be installed according to the installation instructions on the main repo.
You can install youtube-dl with Python's package manager, pip, which we recommend for youtube-dl. You can do it with the command
pip install youtube_dl. Alternatively, you can install it with your system's package manager,apt install youtube-dlon Ubuntu orpacman -S youtube-dlon Arch Linux.
This is an optional dependency for users, but is required as a dev-dependency. It allows Songbird to download audio/video sources from the Internet from a variety of webpages, which it will convert to the Opus audio format Discord uses.
Examples
Full examples showing various types of functionality and integrations can be found in this crate's examples directory.
Contributing
If you want to help out or file an issue, please look over our contributor guidelines!
Attribution
Songbird's logo is based upon the copyright-free image "Black-Capped Chickadee" by George Gorgas White.