No high-level duration info

[Phrogz]

Feature request: I'd love to be able to ask some high-level questions about a file, like:

sound = WaveFile::Reader.new('StartUp.wav')
puts "Duration in milliseconds: #{sound.duration}",
     "Stereo? #{sound.channels==2}"

[jstrait]

Thanks for opening the issue! (And sorry for the delay in responding!)

To get the duration of a file you should be able to do:

Reader.new('file.wav').total_duration

This will return a Duration object. However, the data it returns will be like what you'd see on a stopwatch. E.g. fields for the hours, mintues, seconds, milliseconds equivalent to "01:20:25.543" on a stopwatch. So if you wanted to know the total milliseconds you would have to calculate it manually by multiply the milliseconds x seconds x minutes x hours.

This will give a Format object describing the format of the data being read:

format = WaveFile::Reader.new('file.wav').format
puts format.channels   # For example, '2'
puts format.stereo?     # For example, true
puts format.bits_per_sample   # For example, 16
etc.

However, note that it will return the format the sample data is being read out as, which might be different from the actual format in the file.

For example, this will read that sample data in the same format as what's actually in the file:

Reader.new('file.wav')

While this will read out as mono 16-bit PCM, regardless of the sample format in the file:

Reader.new('file.wav', Format.new(:mono, :pcm_16, 44100))

So in the 2nd case, calling .format would return a Format object that indicates 1 channel, 16 bits per sample, etc.

Hope this helps!

[Phrogz]

Oh…how embarrassing. How could I have missed those? While IMHO they might be better served mixed into the top-level class itself, and perhaps Duration could have a method that does the math itself, it seems that my requests are fully handled already. Kudos! :)