# ffmpeg-ruby

**Repository Path**: anycell/ffmpeg-ruby

## Basic Information

- **Project Name**: ffmpeg-ruby
- **Description**: Ruby interface to the ffmpeg C library. It is able to extract images from videos but do not allow to encode full video.
- **Primary Language**: C
- **License**: MIT
- **Default Branch**: master
- **Homepage**: None
- **GVP Project**: No

## Statistics

- **Stars**: 0
- **Forks**: 0
- **Created**: 2020-11-19
- **Last Updated**: 2020-12-19

## Categories & Tags

**Categories**: Uncategorized

**Tags**: None

## README

# ffmpeg-ruby

[project home on github](http://github.com/gwik/ffmpeg-ruby)

## Summary

ffmpeg-ruby is a ruby C extension binding to ffmpeg/libav* library.

It's main purpose is to extract frame in order to make video thumbnails.
It also give access to main video attributes (frame rate, bit rate, duration, codecs, ...)

So, it doesn't support encoding (at least for now).

## Installation

Download latest sources of ffmpeg from git:
  
    git clone git://source.ffmpeg.org/ffmpeg.git ffmpeg

Configure, optionally with some prefix :

    ./configure --prefix=/opt/ffmpeg --enable-pthreads --enable-shared --enable-gpl
    make
    sudo make install

You can now continue with ffmpeg-ruby.

    git clone git://github.com/kikokikoTHU/ffmpeg-ruby.git
    
    cd ffmpeg-ruby
    gem build ./ffmpeg-ruby.gemspec
    sudo gem install ./ffmpeg-ruby-0.1.0.gem -- --with-ffmpeg-dir=/opt/ffmpeg

You can now test it :

    irb
    >> require 'rubygems'
    => false
    >> require 'ffmpeg'
    => true
    >> FFMPEG
    => FFMPEG

## Tutorial

ffmpeg-ruby does not have real document YET (I promise it will change soom).
You can take a look a specs for in depth usage.

Here is basic usage.

## Video attributes

```ruby
require 'rubygems'
require 'ffmpeg'

video = FFMPEG::InputFormat.new('alligator.mp4')
# => #<FFMPEG::InputFormat:0x5fa3c0>

video.public_methods - Object.public_instance_methods
# => ["bit_rate", "filename", "duration", "has_stream_with_codec_type?", "first_video_stream", "human_duration", "has_video?", "video_stream_count", "streams", "has_audio?", "first_audio_stream", "audio_stream_count"]
```

## Streams

```ruby
video.first_video_stream.public_methods - Object.public_instance_methods
# => ["position", "duration", "index", "codec", "decode_frame", "seek"]
```

### Seeking in stream

```ruby
video.first_video_stream.seek(10)
video.first_video_stream.position
# => 10.2333333333333
```

As you can see, seeking is not very precise.

### Extracting frame

```ruby
frame = video.first_video_stream.decode_frame
# => #<FFMPEG::Frame:0x5c9874>

"frame size #{frame.width}x#{frame.height}"
# => "frame size 240x176"
```

### Animated GIF example with RMagick

    See animated_gif_example.rb