bitPickups/ad-aures_castoPod
1
0
Fork 0
mirror of https://github.com/ad-aures/castopod.git synced 2026-04-11 10:46:43 +02:00
Code Issues Projects Releases Packages Wiki Activity

feat: support VTT transcript file format in addition to SRT

Browse source 
closes #433
This commit is contained in:
Guy Martin 2024-02-09 16:34:50 +00:00 • committed by Yassine Doghri
commit 7071b4b6f4
5 changed files with 123 additions and 9 deletions
Download patch file Download diff file Expand all files Collapse all files

107
modules/Media/TranscriptParser.php
View file

@ -3,7 +3,7 @@
declare(strict_types=1);
/**
* Generates and renders a breadcrumb based on the current url segments
* Converts a SRT or VTT file to JSON
*
* @copyright 2022 Ad Aures
* @license https://www.gnu.org/licenses/agpl-3.0.en.html AGPL3
@ -107,9 +107,114 @@ class TranscriptParser
return $jsonString;
}
public function parseVtt(): string
{
if (! defined('VTT_STATE_HEADER')) {
define('VTT_STATE_HEADER', 0);
}
if (! defined('VTT_STATE_BLANK')) {
define('VTT_STATE_BLANK', 1);
}
if (! defined('VTT_STATE_TIME')) {
define('VTT_STATE_TIME', 2);
}
if (! defined('VTT_STATE_TEXT')) {
define('VTT_STATE_TEXT', 3);
}
$subs = [];
$state = VTT_STATE_HEADER;
$subNum = 0;
$subText = '';
$subTime = '';
$lines = explode(PHP_EOL, $this->transcriptContent);
// add a newline as last item, if it isn't already a newline
if ($lines[array_key_last($lines)] !== '') {
$lines[] = PHP_EOL;
}
foreach ($lines as $line) {
switch ($state) {
case VTT_STATE_HEADER:
$state = VTT_STATE_BLANK;
break;
case VTT_STATE_BLANK:
$state = VTT_STATE_TIME;
break;
case VTT_STATE_TIME:
$subTime = trim($line);
$state = VTT_STATE_TEXT;
break;
case VTT_STATE_TEXT:
if (trim($line) === '') {
$sub = new stdClass();
$sub->number = $subNum;
[$startTime, $endTime] = explode(' --> ', $subTime);
$sub->startTime = $this->getSecondsFromVTTTimeString($startTime);
$sub->endTime = $this->getSecondsFromVTTTimeString($endTime);
$sub->text = trim($subText);
if ($subSpeaker !== '') {
$sub->speaker = trim((string) $subSpeaker);
}
$subText = '';
$state = VTT_STATE_TIME;
$subs[] = $sub;
++$subNum;
} elseif ($subText !== '') {
$subText .= PHP_EOL . $line;
} else {
/** VTT includes a lot of information on the spoken line
* An example may look like this:
* <v.loud.top John>So this is it
* We need to break this down into it's components, namely:
* 1. The actual words for the caption
* 2. Who is speaking
* 3. Any styling cues encoded in the VTT (which we dump)
* More information: https://www.w3.org/TR/webvtt1/
*/
$vtt_speaker_pattern = '/^<.*>/';
$removethese = ['<', '>'];
preg_match($vtt_speaker_pattern, $line, $matches);
if (isset($matches[0])) {
$subVoiceCue = explode(' ', str_replace($removethese, '', $matches[0]));
$subSpeaker = $subVoiceCue[1];
} else {
$subSpeaker = '';
}
$subText .= preg_replace($vtt_speaker_pattern, '', $line);
}
break;
}
}
$jsonString = json_encode($subs, JSON_PRETTY_PRINT);
if (! $jsonString) {
throw new Exception('Failed to parse VTT to JSON.');
}
return $jsonString;
}
private function getSecondsFromTimeString(string $timeString): float
{
$timeString = explode(',', $timeString);
return (strtotime($timeString[0]) - strtotime('TODAY')) + (float) "0.{$timeString[1]}";
}
private function getSecondsFromVTTTimeString(string $timeString): float
{
$timeString = explode('.', $timeString);
return (strtotime($timeString[0]) - strtotime('TODAY')) + (float) "0.{$timeString[1]}";
}
}