https://github.com/asticode/go-astiav
Better C bindings for ffmpeg in GO
https://github.com/asticode/go-astiav
Last synced: 7 months ago
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Better C bindings for ffmpeg in GO
- Host: GitHub
- URL: https://github.com/asticode/go-astiav
- Owner: asticode
- License: mit
- Created: 2022-02-05T09:26:19.000Z (over 3 years ago)
- Default Branch: master
- Last Pushed: 2024-04-14T09:13:45.000Z (about 1 year ago)
- Last Synced: 2024-04-16T00:19:12.663Z (about 1 year ago)
- Language: Go
- Homepage:
- Size: 1.19 MB
- Stars: 169
- Watchers: 9
- Forks: 28
- Open Issues: 5
-
Metadata Files:
- Readme: README.md
- License: LICENSE
Awesome Lists containing this project
- awesome-go - asticode/go-astiav
- awesome-go - asticode/go-astiav
README
[](http://goreportcard.com/report/github.com/asticode/go-astiav)
[](https://godoc.org/github.com/asticode/go-astiav)
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[](https://coveralls.io/github/asticode/go-astiav)
`astiav` is a Golang library providing C bindings for [ffmpeg](https://github.com/FFmpeg/FFmpeg)
It's only compatible with `ffmpeg` `n7.0`.
Its main goals are to:
- [x] provide a better GO idiomatic API
- standard error pattern
- typed constants and flags
- struct-based functions
- ...
- [x] provide the GO version of [ffmpeg examples](https://github.com/FFmpeg/FFmpeg/tree/n7.0/doc/examples)
- [x] be fully tested
# Examples
Examples are located in the [examples](examples) directory and mirror as much as possible the [ffmpeg examples](https://github.com/FFmpeg/FFmpeg/tree/n7.0/doc/examples).
|name|astiav|ffmpeg|
|---|---|---|
|BitStream Filtering|[see](examples/bit_stream_filtering/main.go)|X
|Custom IO Demuxing|[see](examples/custom_io_demuxing/main.go)|[see](https://github.com/FFmpeg/FFmpeg/blob/n7.0/doc/examples/avio_reading.c)
|Custom IO Muxing|[see](examples/custom_io_muxing/main.go)|X
|Demuxing/Decoding|[see](examples/demuxing_decoding/main.go)|[see](https://github.com/FFmpeg/FFmpeg/blob/n7.0/doc/examples/demuxing_decoding.c)
|Filtering|[see](examples/filtering/main.go)|[see](https://github.com/FFmpeg/FFmpeg/blob/n7.0/doc/examples/filtering_video.c)
|Frame data manipulation|[see](examples/frame_data_manipulation/main.go)|X
|Hardware Decoding|[see](examples/hardware_decoding/main.go)|[see](https://github.com/FFmpeg/FFmpeg/blob/n7.0/doc/examples/hw_decode.c)
|Hardware Encoding|[see](examples/hardware_encoding/main.go)|[see](https://github.com/FFmpeg/FFmpeg/blob/n7.0/doc/examples/vaapi_encode.c)
|Remuxing|[see](examples/remuxing/main.go)|[see](https://github.com/FFmpeg/FFmpeg/blob/n7.0/doc/examples/remuxing.c)
|Scaling|[see](examples/scaling/main.go)|[see](https://github.com/FFmpeg/FFmpeg/blob/n7.0/doc/examples/scaling_video.c)
|Transcoding|[see](examples/transcoding/main.go)|[see](https://github.com/FFmpeg/FFmpeg/blob/n7.0/doc/examples/transcoding.c)
*Tip: you can use the video sample located in the `testdata` directory for your tests*
# Patterns
*NB: errors are not checked below for readibility purposes, however you should!*
First off, all use cases are different and it's impossible to provide patterns that work in every situation. That's why `ffmpeg`'s doc or source code should be your ultimate source of truth regarding how to use this library. That's why all methods of this library have been documented with a link referencing the documentation of the C function they use.
However it's possible to give rules of thumb and patterns that fit most use cases and can kickstart most people. Here's a few of them:
## When to call `Alloc()`, `.Unref()` and `.Free()`
Let's take the `FormatContext.ReadFrame()` pattern as an example. The pattern is similar with frames.
```go
// You can allocate the packet once and reuse the same object in the for loop below
pkt := astiav.AllocPacket()
// However, once you're done using the packet, you need to make sure to free it
defer pkt.Free()
// Loop
for {
// We'll use a closure to ease unreferencing the packet
func() {
// Read frame using the same packet every time
formatContext.ReadFrame(pkt)
// However make sure to unreference the packet once you're done with what
// have been "injected" by the .ReadFrame() method
defer pkt.Unref()
// Here you can do whatever you feel like with your packet
}()
}
```
# Breaking changes
You can see the list of breaking changes [here](BREAKING_CHANGES.md).
# Install ffmpeg from source
If you don't know how to install `ffmpeg`, you can use the following to install it from source:
```sh
$ make install-ffmpeg
```
`ffmpeg` will be built from source in a directory named `tmp` and located in you working directory
For your GO code to pick up `ffmpeg` dependency automatically, you'll need to add the following environment variables:
(don't forget to replace `{{ path to your working directory }}` with the absolute path to your working directory)
```sh
export CGO_LDFLAGS="-L{{ path to your working directory }}/tmp/n7.0/lib/",
export CGO_CFLAGS="-I{{ path to your working directory }}/tmp/n7.0/include/",
export PKG_CONFIG_PATH="{{ path to your working directory }}/tmp/n7.0/lib/pkgconfig",
```
## Building on Windows
Building on Windows requires msys2 / mingw64 gcc toolchain. Read the [Quickstart guide](https://www.msys2.org) to install Msys2.
Once complete run the Mingw64 shell from the installation folder, run the below commands:
```shell
# Update Packages
pacman -Syu
# Install Requirements to Build
pacman -S --noconfirm --needed git diffutils mingw-w64-x86_64-toolchain pkg-config make yasm
# Clone the repository using git
git clone https://github.com/asticode/go-astiav
cd go-astiav
```
Then once you clone this repository, follow along the build instructions above.
> **Notes:**
> For `pkg-config` use `pkgconfiglite` from choco.
> Remember to set `CGO` and `PKG_CONFIG` env vars properly to point to the folder where ffmpeg was built.
# Why astiav?
After maintaining for several years the most starred [fork](https://github.com/asticode/goav) of [goav](https://github.com/giorgisio/goav), I've decided to write from scratch my own C bindings to fix most of the problems I still encountered using `goav`.