Class: Audio::MPEG::Decoder

Inherits:
Object
  • Object
show all
Defined in:
lib/icanhasaudio/version.rb,
lib/icanhasaudio/mpeg/decoder.rb,
ext/icanhasaudio/audio_mpeg_decoder.c,
ext/icanhasaudio/audio_mpeg_decoder_mp3data.c

Defined Under Namespace

Classes: MP3Data

Constant Summary collapse

VERSION = 
'0.1.3'

Instance Attribute Summary collapse

Class Method Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize {|_self| ... } ⇒ Decoder

Returns a new instance of Decoder.

Yields:

  • (_self)

Yield Parameters:



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# File 'lib/icanhasaudio/mpeg/decoder.rb', line 8

def initialize
  @bits       = 16
  @raw        = false
  @mp3data    = MP3Data.new
  yield self if block_given?
end

Instance Attribute Details

#bits ⇒ Object

Number of bits, 8 or 16



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# File 'lib/icanhasaudio/mpeg/decoder.rb', line 5

def bits
  @bits
end

#mp3data ⇒ Object (readonly)

Returns the value of attribute mp3data.



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# File 'lib/icanhasaudio/mpeg/decoder.rb', line 6

def mp3data
  @mp3data
end

Class Method Details

.Audio::MPEG::Decoder.lame_version ⇒ Object

Returns the version of lame you are using.



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# File 'ext/icanhasaudio/audio_mpeg_decoder.c', line 42

static VALUE method_lame_version(VALUE klass) {
  const char * version = get_lame_version();
  return rb_str_new(version, strlen(version));
}

Instance Method Details

#decode(input, output) ⇒ Object 



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# File 'lib/icanhasaudio/mpeg/decoder.rb', line 15

def decode input, output
  buf = skip_id3_header(input)

  decode_headers_for(buf)
  while !mp3data.header_parsed?
    decode_headers_for(input.read(100))
  end
  mp3data.nsamp = MP3Data::MAX_U_32_NUM unless mp3data.total_frames > 0
  wav = WAV::File.new(output)
  wav.write_header(0x7FFFFFFF, 0, num_channels, in_samplerate) if !@raw
  native_decode(input, wav)
  if !@raw && attempt_rewind(wav)
    wav.write_header(@wavsize + 44, 0, num_channels, in_samplerate)
  end
end

#in_samplerate ⇒ Object

Get the input samplerate



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# File 'ext/icanhasaudio/audio_mpeg_decoder.c', line 195

static VALUE get_in_samplerate(VALUE self)
{
  lame_global_flags * gfp;
  Data_Get_Struct(self, lame_global_flags, gfp);
  return INT2NUM(lame_get_in_samplerate(gfp));
}

#num_samples=(number) ⇒ Object

Set the number of samples



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# File 'ext/icanhasaudio/audio_mpeg_decoder.c', line 181

static VALUE set_num_samples(VALUE self, VALUE sample_count)
{
  lame_global_flags * gfp;
  Data_Get_Struct(self, lame_global_flags, gfp);
  lame_set_num_samples(gfp, NUM2INT(sample_count));
  return sample_count;
}