Added docs about one-phase (positive only) mode (#4)

Author: maximal

Waveform.php

@@ -16,6 +16,10 @@
 
 namespace maximal\audio;
 
+/**
+ * Waveform class allows you to get waveform data and images from audio files
+ * @package maximal\audio
+ */
 class Waveform
 {
 	protected $filename;
@@ -105,6 +109,15 @@ public function getDuration()
 		return $this->duration;
 	}
 
+	/**
+	 * Get waveform from the audio file.
+	 * @param string $filename Audio file name
+	 * @param int $width Width of the image file in pixels
+	 * @param int $height Height of the image file in pixels
+	 * @param bool $onePhase `true` to get positive values only, `false` to get both phases
+	 * @return bool Returns `true` on success or `false` on failure.
+	 * @throws \Exception
+	 */
 	public function getWaveform($filename, $width, $height, $onePhase = false)
 	{
 		// Calculating parameters
@@ -169,6 +182,13 @@ public function getWaveform($filename, $width, $height, $onePhase = false)
 		return imagepng($img, $filename);
 	}
 
+	/**
+	 * Get waveform data from the audio file.
+	 * @param int $width Desired width of the image file in pixels
+	 * @param bool $onePhase `true` to get positive values only, `false` to get both phases
+	 * @return array
+	 * @throws \Exception
+	 */
 	public function getWaveformData($width, $onePhase = false)
 	{
 		// Calculating parameters

one-phase-mono.png

@@ -48,6 +48,20 @@ $waveform = new Waveform('track.mp3');
 $success = $waveform->getWaveform('thumbnail.png', 1024, 512);
 ```
 
+### One Phase
+To get positive waveform only (i.e. one phase) pass `onePhase` parameter set to `true`:
+```php
+$waveform->getWaveform('one-phase.png', 800, 400, true);
+```
+
+Stereo source:
+
+![One phase stereo](one-phase-stereo.png)
+
+Mono source:
+
+![One phase stereo](one-phase-mono.png)
+
 
 ## Settings
 
@@ -116,6 +130,12 @@ $data = $waveform->getWaveformData($width);
 // $data['lines1'] and $data['lines2'] now have the waveform data for channels 1 and 2
 ```
 
+To get positive values only (i.e. one phase) pass `onePhase` parameter set to `true`:
+
+```php
+$data = $waveform->getWaveformData($width, true);
+```
+
 
 ## Contact the author