Captions can read subtitles of various formats, modify them and convert the subtitle to other formats. Currently captions supports SRT
, WebVTT
files.
- Read subtitles
- Move subtitles
- Increase duration
- Filter subtitles
- Change frame rate
- Convert to other format (SRT, WebVTT)
- Read subtitle properties (Font Style, Aligment, Position etc.)
- Delete subtitles
- Change subtitle fonts
- Command Line Interface
- Spell Check
- And More...
Read subtitle file:
s = Captions::SRT.new('test.srt')
s.parse
s = Captions::VTT.new('test.vtt')
s.parse
Filter subtitles:
Once the subtitle file has been parsed. Every subtitle will get start_time, end_time, duration and text. All the values are stored in milliseconds. Captions::InvalidSubtitle
error will be thown if start-time or end-time cannot be found for a subtitle.
View all subtitle text:
s.cues.map { |c| c.text }
Filter subtitles based on condition:
s.cues { |c| c.start_time > 1000 }
s.cues { |c| c.end_time > 1000 }
s.cues { |c| c.duration > 1000 }
To get all subtitles:
s.cues.each { |c| puts c }
Move Subtitle:
s.move_by(1000)
s.move_by(1000) { |c| c.start_time > 3000 }
Former command moves all subtitles by 1 second. Later moves the subtitles which are starting after 3 seconds by 1 second.
Increase Duration:
s.increase_duration_by(1000)
s.increase_duration_by(1000) { |c| c.start_time > 3000 }
Former command increases duration of all subtitles by 1 second. Later increases the duration of subtitles which are starting after 3 seconds by 1 second.
Change Frame Rate:
All subtitles are parsed based on 25 frames/second by default. This can be changed by passing frame rate at the time of reading the subtitle file.
s = Captions::SRT.new('test.srt', 29.97)
s.parse
Frame rate can also be changed after parsing. This command changes all the subtitles which are parsed in different frame-rate to new frame-rate.
s.set_frame_rate(29.97)
Convert to Other Format:
Subtitles parsed in one format can be converted to other format. Currently export is supported for SRT and WebVTT. Other formats will be added soon.
s = Captions::SRT.new('test.srt')
s.parse
s.export_to_vtt('test.vtt')
Subtitles can also be filtered and those filtered subtitles can be written to a file.
s = Captions::SRT.new('test.srt')
s.parse
new_cues = s.cues { |c| c.start_time > 2000 }
s.export_to_vtt('test.vtt', new_cues)
Filter subtiltes and Export:
Subtitles can be filtered with filter option. This returns a new Captions
object. Once filters new object is created and cues for that becomes the result of the filter. This can be exported to other formats easily.
new_obj = s.filter { |c| c.start_time > 2000 }
new_obj.export_to_vtt('test.vtt')
Add this line to your application's Gemfile:
gem 'captions'
Or install it yourself as:
$ gem install captions
After checking out the repo, run bin/setup
to install dependencies. You can also run bin/console
for an interactive prompt that will allow you to experiment.
To install this gem onto your local machine, run bundle exec rake install
. To release a new version, update the version number in version.rb
, and then run bundle exec rake release
, which will create a git tag for the version, push git commits and tags, and push the .gem
file to rubygems.org.
Bug reports and pull requests are welcome on GitHub at https://github.com/navinre/captions.
The gem is available as open source under the terms of the MIT License.