Class: WaveFile::CachingWriter

Inherits:
Writer
  • Object
show all
Defined in:
lib/wavefile/cachingwriter.rb

Overview

Implementation of Writer that caches the raw wave data for each buffer that it has written. If the Buffer is written again, it will write the version from cache instead of re-doing a String.pack() call.

Instance Method Summary collapse

Constructor Details

#initialize(file_name, format) ⇒ CachingWriter

Returns a new instance of CachingWriter.



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# File 'lib/wavefile/cachingwriter.rb', line 6

def initialize(file_name, format)
  super

  @buffer_cache = {}
end

Instance Method Details

#write(buffer) ⇒ Object 



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# File 'lib/wavefile/cachingwriter.rb', line 12

def write(buffer)
  packed_buffer_data = {}
  
  key = buffer.hash
  if @buffer_cache.member?(key)
    packed_buffer_data = @buffer_cache[key]
  else
    samples = buffer.convert(@format).samples

    if @format.channels > 1
      data = samples.flatten.pack(@pack_code)
    else
      # Flattening an already flat array is a waste of time.
      data = samples.pack(@pack_code)
    end

    packed_buffer_data = { :data => data, :sample_count => samples.length }
    @buffer_cache[key] = packed_buffer_data
  end

  @file.syswrite(packed_buffer_data[:data])
  @total_sample_frames += packed_buffer_data[:sample_count]
end