247 lines
7.3 KiB
Markdown
247 lines
7.3 KiB
Markdown
---
|
|
title:
|
|
- Multimedia using Rust and GStreamer
|
|
author:
|
|
- Sanchayan Maity
|
|
aspectratio:
|
|
- 169
|
|
fontsize:
|
|
- 14pt
|
|
papersize:
|
|
- "presentation-16-9"
|
|
---
|
|
|
|
## Who?
|
|
|
|
- Consultant Software Engineer @ [asymptotic](https://asymptotic.io/)
|
|
- Open source consulting firm based out of Toronto, Bangalore & Hyderabad
|
|
- Work on low level systems software centred around multimedia
|
|
- GStreamer, PipeWire, PulseAudio
|
|
- Embedded Systems background
|
|
- C, Rust and Haskell
|
|
- Organizing Rust and Haskell meetup Bangalore since 2018
|
|
|
|
## Agenda
|
|
|
|
- Introduction to GStreamer
|
|
- Why Rust
|
|
- Rust and GStreamer
|
|
|
|
## GStreamer
|
|
|
|
- Multiplatform Pipeline based multimedia framework
|
|
- Bindings for various languages
|
|
- Supported on Linux, macOS, Android and Windows
|
|
- Allows building complex media processing workflows
|
|
- Some applications
|
|
* GstLAL (gravitational wave data analysis)
|
|
* PiTiVi (Video Editor)
|
|
* amaroK, Banshee, Clementine (audio players)
|
|
* Empathy (VOIP and video conferencing)
|
|
* Rygel (DLNA streaming server and renderer)
|
|
* Showtime, Clapper, Totem (Media players for desktop)
|
|
|
|
## Simple pipeline
|
|
|
|
```bash
|
|
gst-launch-1.0 videotestsrc ! autovideosink
|
|
gst-launch-1.0 audiotestsrc ! autoaudiosink
|
|
```
|
|
|
|
## Media pipeline[^1]
|
|
|
|
{width=80%}
|
|
|
|
[^1]: [Dynamic Pipelines](https://gstreamer.freedesktop.org/documentation/tutorials/basic/dynamic-pipelines.html?gi-language=c)
|
|
|
|
## Playback pipeline
|
|
|
|
```bash
|
|
gst-play-1.0 https://devstreaming-cdn.apple.com/videos/streaming/examples/img_bipbop_adv_example_ts/master.m3u8
|
|
```
|
|
|
|
## Playback pipeline graph
|
|
|
|
|
|
|
|
## Custom elements
|
|
|
|
{width=58%}
|
|
|
|
```bash
|
|
gst-launch-1.0 filesrc location=bunny.mp4 ! decodebin ! videoconvert ! roundedcorners border-radius-px=100 ! videoconvert ! gtksink
|
|
```
|
|
|
|
## Why Rust?
|
|
|
|
- Codec implementations in pure Rust (Rust Audio, Xiph AV1, Symphonia)
|
|
- Things we care about
|
|
* **Low cognitive overhead**
|
|
* Immutability
|
|
* Expressive type system
|
|
* Memory safety and concurrency
|
|
* Foreign Function Interface
|
|
|
|
## Why Rust?
|
|
|
|
- Bindings/abstractions over GLib/GObject and for GStreamer[^2]
|
|
- Provides a root for the object hierarchy tree filed in by the GStreamer library
|
|
- Gives basic reference counting, parenting functionality and locking.
|
|
- GObject
|
|
- GstObject
|
|
- GstAllocator
|
|
- GstBufferPool
|
|
- GstBus
|
|
- GstClock
|
|
- GstDevice
|
|
- GstDeviceMonitor
|
|
- GstDeviceProvider
|
|
- GstElement
|
|
- GstPad
|
|
|
|
[^2]: [GstObject](https://gstreamer.freedesktop.org/documentation/gstreamer/gstobject.html?gi-language=c)
|
|
|
|
## Why immutability and types matter?
|
|
|
|
```c
|
|
let caps: gst::Caps = gst::Caps::builder("video/x-raw")
|
|
.field("width", crop_w)
|
|
.field("height", crop_h)
|
|
.field("pixel-aspect-ratio", gst::Fraction::new(1, 1))
|
|
.build();
|
|
let s = caps.remove_structure(0);
|
|
```
|
|
|
|
## Why immutability and types matter?
|
|
|
|
```bash
|
|
warning: unused variable: `s`
|
|
--> video-bin/src/imp.rs:152:13
|
|
|
|
|
152 | let s = caps.remove_structure(0);
|
|
| ^ help: if this is intentional, prefix it with an
|
|
underscore: `_s`
|
|
|
|
|
= note: `#[warn(unused_variables)]` on by default
|
|
error[E0596]: cannot borrow data in dereference of `gstreamer::Caps`
|
|
as mutable
|
|
--> video-bin/src/imp.rs:152:17
|
|
|
|
|
152 | let s = caps.remove_structure(0);
|
|
| ^^^^^^^^^^^^^^^^^^^^^^^^ cannot borrow as mutable
|
|
|
|
|
= help: trait `DerefMut` is required to modify through a dereference,
|
|
but it is not implemented for `gstreamer::Caps`
|
|
```
|
|
|
|
## Why immutability and types matter?
|
|
|
|
```c
|
|
let mut caps: gst::Caps = gst::Caps::builder("video/x-raw")
|
|
.field("width", crop_w)
|
|
.field("height", crop_h)
|
|
.field("pixel-aspect-ratio", gst::Fraction::new(1, 1))
|
|
.build();
|
|
let _s = caps.remove_structure(0);
|
|
```
|
|
|
|
|
|
## Why immutability and types matter?
|
|
|
|
```bash
|
|
warning: variable does not need to be mutable
|
|
--> video-bin/src/imp.rs:147:13
|
|
|
|
|
147 | let mut caps: gst::Caps = gst::Caps::builder("video/x-raw")
|
|
| ----^^^^
|
|
| |
|
|
| help: remove this `mut`
|
|
|
|
|
= note: `#[warn(unused_mut)]` on by default
|
|
error[E0596]: cannot borrow data in dereference of `gstreamer::Caps`
|
|
as mutable
|
|
--> video-bin/src/imp.rs:152:18
|
|
|
|
|
152 | let _s = caps.remove_structure(0);
|
|
| ^^^^^^^^^^^^^^^^^^^^^^^^ cannot borrow as mutable
|
|
= help: trait `DerefMut` is required to modify through a dereference,
|
|
but it is not implemented for `gstreamer::Caps`
|
|
```
|
|
|
|
## Why immutability and types matter?
|
|
|
|
```c
|
|
let caps: gst::Caps = gst::Caps::builder("video/x-raw")
|
|
.field("width", crop_w)
|
|
.field("height", crop_h)
|
|
.field("pixel-aspect-ratio", gst::Fraction::new(1, 1))
|
|
.build();
|
|
let caps = caps.get_mut().unwrap();
|
|
let _s = caps.remove_structure(0);
|
|
```
|
|
|
|
## Why immutability and types matter?
|
|
|
|
```bash
|
|
error[E0596]: cannot borrow `caps` as mutable, as it is not declared
|
|
as mutable
|
|
--> video-bin/src/imp.rs:152:20
|
|
|
|
|
147 | let caps: gst::Caps = gst::Caps::builder("video/x-raw")
|
|
| ---- help: consider changing this to be mutable:
|
|
`mut caps`
|
|
...
|
|
152 | let caps = caps.get_mut().unwrap();
|
|
| ^^^^^^^^^^^^^^ cannot borrow as mutable
|
|
|
|
For more information about this error, try `rustc --explain E0596`.
|
|
```
|
|
|
|
## Why immutability and types matter?
|
|
|
|
```c
|
|
let mut caps: gst::Caps = gst::Caps::builder("video/x-raw")
|
|
.field("width", crop_w)
|
|
.field("height", crop_h)
|
|
.field("pixel-aspect-ratio", gst::Fraction::new(1, 1))
|
|
.build();
|
|
if let Some(caps) = caps.get_mut() {
|
|
let _s = caps.remove_structure(0);
|
|
}
|
|
```
|
|
|
|
## GStreamer & Rust
|
|
|
|
- Some stats[^3]
|
|
- gstreamer-rs: ~2700 commits, gst-plugins-rs: ~2600 commits
|
|
- gstreamer-rs: ~85 contributors, gst-plugins-rs: ~110 contributors
|
|
- gst-plugins-rs: ~ +180k SLOC / -37k SLOC
|
|
- gst-plugins-rs: Overall 47 plugins, 149 elements
|
|
- In relation to the GStreamer monorepo
|
|
- 1.22 cycle: ~33% commits / MRs in Rust modules
|
|
- 1.24 cycle: ~25% commits / MRs in Rust modules
|
|
|
|
[^3]: [GStreamer & Rust: What has happened over the last 5 years](https://gstconf.ubicast.tv/videos/gstreamer-rust-what-has-happened-over-the-last-5-years_f8qxhpuzi9/)
|
|
|
|
## Resources
|
|
|
|
- [GObject subclassing in Rust ](https://www.youtube.com/watch?v=TSf3rVyv7c8)
|
|
- [GStreamer bindings for Rust](https://gitlab.freedesktop.org/gstreamer/gstreamer-rs)
|
|
- [Rust GStreamer Plugins](https://gitlab.freedesktop.org/gstreamer/gst-plugins-rs)
|
|
- [Using GStreamer](https://www.youtube.com/watch?v=ZphadMGufY8)
|
|
- [How to get started with GStreamer](https://www.youtube.com/watch?v=OkOsm9FyzdM&t=2s)
|
|
- [GStreamer for your backend services](https://asymptotic.io/blog/gstreamer-for-your-backend-services/)
|
|
|
|
## Questions?
|
|
|
|
- Rust Bangalore
|
|
* Meetup: https://hasgeek.com/rustbangalore
|
|
* Telegram: t.me/RustIndia
|
|
- Reach out on
|
|
* email:
|
|
|
|
- me@sanchayanmaity.net
|
|
- sanchayan@asymptotic.io
|
|
- hello@asymptotic.io
|
|
* Mastodon: [sanchayanmaity.com](https://sanchayanmaity.com/@sanchayan)
|
|
* Blog: [sanchayanmaity.net](https://sanchayanmaity.net/)
|