X-Git-Url: http://p2p-next.cs.pub.ro/gitweb/?a=blobdiff_plain;f=application%2Fhelpers%2Fvideo_helper.php;h=aa7c3841c2dd8469234a50c2ef9e7e61bfa84d0a;hb=HEAD;hp=64efee576f7a433fb1daf85584e8aa69d18b5162;hpb=211dc651c32bb8998b3eb2fdd3a3b85fc31921ec;p=living-lab-site.git

diff --git a/application/helpers/video_helper.php b/application/helpers/video_helper.php
index 64efee5..aa7c384 100644
--- a/application/helpers/video_helper.php
+++ b/application/helpers/video_helper.php
@@ -100,5 +100,190 @@ function get_closest_res($haystack, $needle, $access_function = NULL)
 	return $i_min;
 }
 
+/**
+ * "Private" function used by get_av_info which returns the value from a
+ * "key=value" formatted string.
+ * 
+ * @param string $str_key_value a string formatted as key=value
+ * @return string
+ */
+function _parse_value($str_key_value)
+{
+	return trim(substr(
+			$str_key_value, 
+			strpos($str_key_value, '=') + 1,
+			strlen($str_key_value)
+			));
+}
+
+/**
+ * Formats the floating number of seconds to a string with format [HH:]mm:ss .
+ * 
+ * @param float $secs
+ * @return string 
+ */
+function format_duration($secs)
+{
+	$secs = intval(round($secs));
+	
+	$h = intval(floor($secs / 3600));
+	$m = intval(floor(($secs % 3600) / 60));
+	$s = $secs % 3600 % 60;
+	
+	$duration = sprintf('%02d', $m) . ':' . sprintf('%02d', $s);
+	
+	if ($h > 0)
+		return sprintf('%02d', $h) . ':' . $duration;
+	
+	return $duration;
+}
+
+/**
+ * Returns information about an Audio/Video file.
+ * 
+ * @param string $file_name Audio/Video file
+ * @return dictionary FALSE on error or a dictionary of audio/video properties
+ * with the following keys otherwise:
+ * <ul>
+ *   <li>width</li>
+ *   <li>height</li>
+ *   <li>dar (display aspect ratio)</li>
+ *   <li>duration (formated as [HH:]mm:ss)</li>
+ *   <li>size (in bytes)</li>
+ * </ul>
+ */
+function get_av_info($file_name)
+{
+	$h = popen('ffprobe -show_streams -show_format "'
+			. $file_name . '" 2> /dev/null', 'r');
+
+	$tag = NULL;
+	$codec_type = NULL;
+	
+	while ( ($r = fgets($h, 512)) !== FALSE)
+	{
+		// Match tags.
+		if (preg_match('/^\[FORMAT\]/', $r))
+		{
+			$tag = 'FORMAT';	
+			continue;
+		}
+		if (preg_match('/^\[STREAM\]/', $r))
+		{
+			$tag = 'STREAM';
+			continue;
+		}
+		
+		if ($tag == 'FORMAT')
+		{
+			// Size
+			if (preg_match('/^size=/', $r))
+				$size = intval(_parse_value ($r));
+		}
+		
+		if ($tag == 'STREAM')
+		{
+			// Width
+			if (preg_match('/^width=/', $r))
+				$width = intval(_parse_value($r));
+			
+			// Height
+			if (preg_match('/^height=/', $r))
+				$height = intval(_parse_value($r));
+			
+			// DAR
+			if (preg_match('/^display_aspect_ratio=/', $r))
+				$dar = _parse_value($r);
+			
+			// Codec Type
+			if (preg_match('/^codec_type=/', $r))
+				$codec_type = _parse_value($r);
+			
+			// Duration
+			if (preg_match('/^duration=/', $r)
+					&& strcmp($codec_type, 'video') == 0)
+				$duration = format_duration(floatval(_parse_value($r)));
+		}
+	}
+	
+	if (pclose($h) > 0)
+		return FALSE;
+	
+	return array('width'=>$width, 'height'=>$height, 'dar'=>$dar,
+		'duration'=>$duration, 'size'=>$size);
+	
+//	return array('width'=> 1440, 'height'=> 1080, 'dar'=> '16:9',
+//			'duration'=> '00:10', 'size'=> 5568748);
+}
+
+/**
+ * Return a dictionary with formats compliant for DB and CIS and computes
+ * resolutions such that an uploaded video will not be converted to a higher
+ * resolution.
+ * 
+ * @param type $formats formats as in content_ingestion config file
+ * @param type $av_info structure as returned by get_av_info function from this
+ * helper
+ * @param type $elim_dupl_res eliminate consecutive formats with the same
+ * resolution
+ * @return array a dictionary with DB format at key 'db_formats' and CIS format
+ * at key 'transcode_configs' 
+ */
+function prepare_formats($formats, $av_info, $elim_dupl_res=FALSE)
+{
+	$transcode_configs = array();
+	$db_formats = array();
+	
+	for ($i = 0; $i < count($formats); $i++)
+	{
+		$transcode_configs[$i]['container'] = $formats[$i]['container'];
+		$transcode_configs[$i]['extension'] = $formats[$i]['extension'];
+		$db_formats[$i]['ext'] = $formats[$i]['extension'];
+		$transcode_configs[$i]['a_codec'] = $formats[$i]['audio_codec'];
+		$transcode_configs[$i]['a_bitrate'] = $formats[$i]['audio_bit_rate'];
+		$transcode_configs[$i]['a_samplingrate'] = $formats[$i]['audio_sampling_rate'];
+		$transcode_configs[$i]['a_channels'] = $formats[$i]['audio_channels'];
+		$transcode_configs[$i]['v_codec'] = $formats[$i]['video_codec'];
+		$transcode_configs[$i]['v_bitrate'] = $formats[$i]['video_bit_rate'];
+		$transcode_configs[$i]['v_framerate'] = $formats[$i]['video_frame_rate'];
+		$transcode_configs[$i]['v_dar'] = $av_info['dar'];
+		$db_formats[$i]['dar'] = $av_info['dar'];
+
+		$sar = $av_info['width'] / $av_info['height'];
+		
+		if ($av_info['height'] < $formats[$i]['video_height'])
+		{
+			$width = $av_info['width'];
+			$height = $av_info['height'];
+		}
+		else
+		{
+			$height = $formats[$i]['video_height'];
+			$width = round($sar * $height);
+		}
+		
+		$transcode_configs[$i]['v_resolution'] = "${width}x${height}";
+		$db_formats[$i]['res'] = "${width}x${height}";
+	}
+	
+	// Eliminate formats with duplicate resolutions.
+//	if ($elim_dupl_res)
+//	{
+//		for ($i = 1; $i < count($transcode_configs); $i++)
+//		{
+//			if ($transcode_configs[$i]['v_resolution']
+//					=== $transcode_configs[$i - 1]['v_resolution'])
+//			{
+//				unset($transcode_configs[$i - 1]);
+//				unset($db_formats[$i - 1]);
+//				$i--;
+//			}
+//		}
+//	}
+	
+	return array('transcode_configs'=>$transcode_configs,
+		'db_formats'=>$db_formats);
+}
+
 /* End of file video_helper.php */
 /* Location: ./application/helpers/video_helper.php */
\ No newline at end of file