protected function _createAudio()
{
if (is_null($this->_key)) {
throw new \Exception('Key must be generated');
}
// TODO need get IT, DE and ES audio files
//http://www.gilles-joyeux.fr/MP3/NEn.mp3 letters
//http://www.gilles-joyeux.fr/MP3/ten.mp3 numbers
// revoir les sons S et F en anglais ...
try {
$globalWavFile = new \WavFile();
// Set sample rate, bits/sample, and Num of channels // TODO setter and getter this params ?
$globalWavFile->setSampleRate(8000);
$globalWavFile->setBitsPerSample(8);
$globalWavFile->setNumChannels(1);
$letters = str_split(strtoupper($this->_key));
foreach ($letters as $letter) {
if (!file_exists($this->_audioLangDirectory . $letter . '.wav')) {
throw new \Exception('Audio file : "' . $this->_audioLangDirectory . $letter . '.wav' . '" miss');
}
$l = new \WavFile($this->_audioLangDirectory . $letter . '.wav');
// append letter to the captcha audio
$globalWavFile->appendWav($l);
// random silence between letters
$globalWavFile->insertSilence(mt_rand($this->_audioLettersGapMin, $this->_audioLettersGapMax) / 1000.0);
//rand min and max
}
// Add filters
$filters = array();
// noise by sound file
if ($this->_audioNoise) {
// use background audio
$wavNoise = new \WavFile($this->_audioNoiseFile, false);
$wavNoise->setSampleRate($globalWavFile->getSampleRate())->setBitsPerSample($globalWavFile->getBitsPerSample())->setNumChannels($globalWavFile->getNumChannels());
// start at a random offset from the beginning of the wav file in order to add more randomness
$randOffset = 0;
if ($wavNoise->getNumBlocks() > 2 * $globalWavFile->getNumBlocks()) {
$randBlock = rand(0, $wavNoise->getNumBlocks() - $globalWavFile->getNumBlocks());
$wavNoise->readWavData($randBlock * $wavNoise->getBlockAlign(), $globalWavFile->getNumBlocks() * $wavNoise->getBlockAlign());
} else {
$wavNoise->readWavData();
$randOffset = rand(0, $wavNoise->getNumBlocks() - 1);
}
$mixOpts = array('wav' => $wavNoise, 'loop' => true, 'blockOffset' => $randOffset);
$filters[\WavFile::FILTER_MIX] = $mixOpts;
$filters[\WavFile::FILTER_NORMALIZE] = $this->_audioNoiseMixNormalization;
}
// add random noise. Any noise level below 95% is intensely distorted and not pleasing to the ear
if ($this->_audioDegrade) {
$filters[\WavFile::FILTER_DEGRADE] = rand(95, 98) / 100.0;
}
// apply filters to audio file
if (count($filters) > 0) {
$globalWavFile->filter($filters);
}
// save
$this->_audioContents = $globalWavFile->makeHeader();
$this->_audioContents .= $globalWavFile->getDataSubchunk();
unset($globalWavFile);
} catch (\Exception $e) {
Logger::getInstance()->debug('Security captcha generate audio file for form : "' . $this->getFormName() . '" error : "' . $e . '"', 'security');
if (file_exists($this->_audioLangDirectory . 'error.wav')) {
$this->_audioContents = file_get_contents($this->_audioLangDirectory . 'error.wav');
}
}
}