public static function webvtt2subrip(WebvttFile $_vtt)
{
$srt = new SubripFile();
foreach ($_vtt->getCues() as $cue) {
$srt->addCue($cue->getText(), SubripCue::ms2tc($cue->getStartMS()), SubripCue::ms2tc($cue->getStopMS()));
}
return $srt;
}
public function testWebvtt2SubripConversion()
{
// example file from W3C spec
$filename = __DIR__ . '/../Fixtures/example-1.vtt';
$file = new WebvttFile($filename);
$content = "1\n00:00:00,000 --> 00:00:20,000\n<v Fred>Hi, my name is Fred,\nnice to meet you.\n\n2\n00:00:02,500 --> 00:00:22,500\n<v Bill>Hi, I'm Bill.\n\n3\n00:00:05,000 --> 00:00:25,000\n<v Fred>Would you like to get a coffee?\n\n4\n00:00:07,500 --> 00:00:27,500\n<v Bill>Sure! I've only had one today.\n\n5\n00:00:10,000 --> 00:00:30,000\n<v Fred>This is my fourth!\n\n6\n00:00:12,500 --> 00:00:32,500\n<v Fred>OK, let's go.\n\n";
$this->assertEquals($content, $file->convertTo('subrip')->build()->getFileContent());
}
/**
* Generates sprite and WebVTT for selected video
*
* @throws \Exception
*/
public function generate()
{
// create temporay directory
$tempDir = new Tempdir('sprite');
$tempDir->addPlugin(new ListFiles());
// get basic info about video
$ffprobe = FFProbe::create()->format($this->getSource());
$duration = floatval($ffprobe->get('duration'));
// check if sample rate is high enough to reach desired minimum amount of thumbnails
if ($duration <= $this->getMinThumbs()) {
// we only have a 1 second resolution, so we can't get lower than 1 obviously
$this->setRate(1);
} else {
if ($duration / $this->getRate() < $this->getMinThumbs()) {
// sample rate too high, let's adjust rate a little
$this->setRate(floor($duration / $this->getMinThumbs()));
}
}
// capture images to tempdir
for ($i = 0; $i <= $duration; $i += $this->getRate()) {
$cmd = sprintf('ffmpeg -y -ss %d -i %s -frames:v 1 -filter:v scale=%d:-1 %s/%04d.jpg', $i, $this->getSource(), $this->getWidth(), $tempDir->getPath(), floor($i / $this->getRate()));
$proc = new Process($cmd);
$proc->setTimeout(null);
$proc->run();
if (!$proc->isSuccessful()) {
throw new \RuntimeException($cmd . ":" . $proc->getErrorOutput());
}
}
// combine all images to one sprite with quadratic tiling
$gridSize = ceil(sqrt(count($tempDir->listFiles())));
$firstImage = Image::make(sprintf('%s/0001.jpg', $tempDir->getPath()));
$spriteFile = sprintf('%s/%s.jpg', $this->getOutputDirectory(), $this->getPrefix());
$spriteUrl = empty($this->getUrlPrefix()) ? basename($spriteFile) : sprintf('%s/%s', $this->getUrlPrefix(), basename($spriteFile));
$cmd = sprintf('montage %1$s/*.jpg -tile %2$dx -geometry %3$dx%4$d+0+0 %5$s', $tempDir->getPath(), $gridSize, $firstImage->width(), $firstImage->height(), $spriteFile);
$proc = new Process($cmd);
$proc->run();
if (!$proc->isSuccessful()) {
throw new RuntimeException($proc->getErrorOutput());
}
// create WebVTT output
$vttFile = sprintf('%s/%s.vtt', $this->getOutputDirectory(), $this->getPrefix());
$vtt = new WebvttFile();
for ($i = 0; $i < count($tempDir->listFiles()); $i++) {
$start = $i * $this->getRate();
$end = ($i + 1) * $this->getRate();
$x = $i % $gridSize * $firstImage->width();
$y = floor($i / $gridSize) * $firstImage->height();
$vtt->addCue(new WebvttCue($this->secondsToCue($start), $this->secondsToCue($end), sprintf('%s#xywh=%d,%d,%d,%d', $spriteUrl, $x, $y, $firstImage->width(), $firstImage->height())));
}
$vtt->build();
$vtt->save($vttFile);
}
