Added video transcription

app/Services/FileTools/VideoDescriptor/AbstractLLMVideoDescriptor.php

@@ -56,4 +56,33 @@ abstract class AbstractLLMVideoDescriptor implements IVideoDescriptor
         }
         return $array;
     }
+
+    /**
+     * Extract audio from the video file.
+     * Using ffmpeg to extract audio from the video file.
+     * The audio will be saved in a temporary directory as an MP3 file.
+     * If the audio extraction fails, it will return null.
+     * @param string $filePath
+     * @return string|null
+     */
+    protected function extractAudioFromVideo(string $filePath): ?string
+    {
+        $tempDir = sys_get_temp_dir() . '/video_audio';
+        if (!is_dir($tempDir)) {
+            mkdir($tempDir, 0777, true);
+        }
+        else {
+            // Clear the directory if it already exists
+            array_map('unlink', glob($tempDir . '/*'));
+        }
+
+        $outputFile = $tempDir . '/audio.mp3';
+        $command = "ffmpeg -i " . escapeshellarg($filePath) . " " . escapeshellarg($outputFile);
+        exec($command);
+
+        if (file_exists($outputFile)) {
+            return $outputFile;
+        }
+        return null;
+    }
 }