/**
* {@inheritdoc}
*/
public function read()
{
$chunkID = BinaryReader::read($this->resource, 'a*', 4);
if ($chunkID !== 'RIFF') {
return false;
}
$this->riff->setChunkID($chunkID);
$this->riff->setChunkSize(BinaryReader::read($this->resource, 'V', 4));
$this->riff->setFormat(BinaryReader::read($this->resource, 'a*', 4));
$this->fmt->setSubchunk1ID(BinaryReader::read($this->resource, 'a*', 4));
$this->fmt->setSubchunk1Size(BinaryReader::read($this->resource, 'V', 4));
$this->fmt->setAudioFormat(BinaryReader::read($this->resource, 'v', 2));
$this->fmt->setNumChannels(BinaryReader::read($this->resource, 'v', 2));
$this->fmt->setSampleRate(BinaryReader::read($this->resource, 'V', 4));
$this->fmt->setByteRate(BinaryReader::read($this->resource, 'V', 4));
$this->fmt->setBlockAlign(BinaryReader::read($this->resource, 'v', 2));
$this->fmt->setBitsPerSample(BinaryReader::read($this->resource, 'v', 2));
$this->fmt->setExtraParamSize(0);
$this->fmt->setExtraParams(null);
if ($this->fmt->getAudioFormat() != 1) {
$this->fmt->setExtraParamSize(BinaryReader::read($this->resource, 'v', 2));
$this->fmt->setExtraParams(BinaryReader::read($this->resource, 'a*', $this->fmt->getExtraParamSize()));
}
$this->data->setSubchunk2ID(BinaryReader::read($this->resource, 'a*', 4));
$this->data->setSubchunk2Size(BinaryReader::read($this->resource, 'V', 4));
switch ($this->fmt->getAudioFormat()) {
case 1:
$this->fmt->setAudioFormat('PCM');
break;
case 2:
$this->fmt->setAudioFormat('Microsoft ADPCM');
break;
case 6:
$this->fmt->setAudioFormat('ITU G.711 a-law');
break;
case 7:
$this->fmt->setAudioFormat('ITU G.711 ยต-law');
break;
case 17:
$this->fmt->setAudioFormat('IMA ADPCM');
break;
case 20:
$this->fmt->setAudioFormat('ITU G.723 ADPCM (Yamaha)');
break;
case 49:
$this->fmt->setAudioFormat('GSM 6.10');
break;
case 64:
$this->fmt->setAudioFormat('ITU G.721 ADPCM');
break;
case 80:
$this->fmt->setAudioFormat('MPEG');
break;
case 65536:
$this->fmt->setAudioFormat('Experimental');
break;
}
return $this;
}
