Pixel encoder changed to raw pixel encoder

Author: andrewdalpino

CHANGELOG.md

@@ -1,4 +1,4 @@
-- Unreleased
+- 0.0.4-alpha
     - Added Dropout hidden layer
     - Added K-d Neighbors classifier and regressor
     - Added Extra Tree Regressor
@@ -14,6 +14,8 @@
     - Added min dimensionality estimation on random projectors
     - Added Gaussian Random Projector
     - Removed Ellipsoidal distance kernel
+    - Added Thresholded ReLU activation function
+    - Changed API of Raw Pixel Encoder
 
 - 0.0.3-alpha
     - Added Extra Tree classifier

README.md

@@ -37,7 +37,7 @@ MIT
 			- [Unlabeled](#unlabeled)
 	- [Feature Extractors](#feature-extractors)
     	- [Word Count Vectorizer](#word-count-vectorizer)
-		- [Pixel Encoder](#pixel-encoder)
+		- [Raw Pixel Encoder](#raw-pixel-encoder)
 	- [Estimators](#estimators)
 		- [Anomaly Detectors](#anomaly-detectors)
 			- [Isolation Forest](#isolation-forest)
@@ -765,16 +765,15 @@ use Rubix\ML\Extractors\Tokenizers\Word;
 $extractor = new WordCountVectorizer(5000, ['the', 'what', 'has'], true, new Word());
 ```
 
-### Pixel Encoder
-Images must first be converted to color channel values in order to be passed to an Estimator. The Pixel Encoder takes an array of images (as [PHP Resources](http://php.net/manual/en/language.types.resource.php)) and converts them to a flat vector of color channel data. Image scaling and cropping is handled automatically by [Intervention Image](http://image.intervention.io/). The GD extension is required to use this feature.
+### Raw Pixel Encoder
+The Raw Pixel Encoder takes an array of images (as [PHP Resources](http://php.net/manual/en/language.types.resource.php)) and converts them to a flat vector of raw color channel data. Scaling and cropping is handled automatically by [Intervention Image](http://image.intervention.io/) for PHP. Note that the GD extension is required to use this feature.
 
 ##### Parameters:
 | # | Param | Default | Type | Description |
 |--|--|--|--|--|
 | 1 | size | [32, 32] | array | A tuple of width and height values denoting the resolution of the encoding. |
 | 2 | rgb | true | bool | True to use RGB color channel data and False to use Greyscale. |
-| 3 | sharpen | 0 | int | A value between 0 and 100 indicating the amount of sharpness to add to each sample. |
-| 4 | driver | 'gd' | string | The PHP extension to use for image processing ('gd' *or* 'imagick'). |
+| 3 | driver | 'gd' | string | The PHP extension to use for image processing ('gd' *or* 'imagick'). |
 
 ##### Additional Methods:
 This Extractor does not have any additional methods.
@@ -783,7 +782,7 @@ This Extractor does not have any additional methods.
 ```php
 use Rubix\ML\Extractors\PixelEncoder;
 
-$extractor = new PixelEncoder([28, 28], false, 'imagick');
+$extractor = new PixelEncoder([28, 28], true, 'gd');
 ```
 
 ---

programs/MushroomClassifier.php

@@ -46,7 +46,7 @@
 
 $hidden = [
     new Dense(20, new ThresholdedReLU(0.0)),
-    new Dense(20, new ThresholdedReLU(0.0)),
+    new Dense(25, new ThresholdedReLU(0.0)),
     new Dense(20, new ThresholdedReLU(0.0)),
 ];
 

src/Extractors/PixelEncoder.php renamed to src/Extractors/RawPixelEncoder.php

@@ -8,19 +8,18 @@
 use RuntimeException;
 
 /**
- * Pixel Encoder
+ * Raw Pixel Encoder
  *
- * Images must first be converted to color channel values in order to be passed
- * to an Estimator. The Pixel Encoder takes an array of images (as PHP Resources)
- * and converts them to a flat vector of color channel data. Image scaling and
- * cropping is handled automatically by Intervention Image. The GD extension is
- * required to use this feature.
+ * The Raw Pixel Encoder takes an array of images (as PHP Resources)
+ * and converts them into a flat vector of raw color channel data. Scaling and
+ * cropping is handled automatically by Intervention Image for PHP. Note that
+ * the GD extension is required to use this feature.
  *
  * @category    Machine Learning
  * @package     Rubix/ML
  * @author      Andrew DalPino
  */
-class PixelEncoder implements Extractor
+class RawPixelEncoder implements Extractor
 {
     /**
      * The image will be scaled and cropped according to the setting of this
@@ -31,21 +30,12 @@ class PixelEncoder implements Extractor
     protected $size;
 
     /**
-     * The number of channels to encode. Each channel requires width x height
-     * number of features.
+     * The number of color channels to encode.
      *
      * @var int
      */
     protected $channels;
 
-    /**
-     * The amount of sharpness to apply to the image before vectorization.
-     * 0 - 100.
-     *
-     * @var int
-     */
-    protected $sharpen;
-
     /**
      * The Intervention image manager instance.
      *
@@ -60,29 +50,25 @@ class PixelEncoder implements Extractor
      * @throws \InvalidArgumentException
      * @return void
      */
-    public function __construct(array $size = [32, 32], bool $rgb = true,
-                                int $sharpen = 0, string $driver = 'gd')
+    public function __construct(array $size = [32, 32], bool $rgb = true, string $driver = 'gd')
     {
         if (count($size) !== 2) {
             throw new InvalidArgumentException('Size must have a width and a'
                 . ' height.');
         }
 
-        foreach ($size as $dimension) {
-            if ($dimension < 1) {
-                throw new InvalidArgumentException('Width and height must be'
-                    . ' greater than 1 pixel.');
-            }
+        if (!is_int($size[0]) and !is_int($size[1])) {
+            throw new InvalidArgumentException('Width and height must be'
+                . ' integers.');
         }
 
-        if ($sharpen < 0 or $sharpen > 100) {
-            throw new InvalidArgumentException('Sharpness factor must be'
-                . ' between 0 and 100');
+        if ($size[0] < 1 or $size[1] < 1) {
+            throw new InvalidArgumentException('Width and height must be'
+                . ' greater than 1 pixel.');
         }
 
         $this->size = $size;
         $this->channels = $rgb ? 3 : 1;
-        $this->sharpen = $sharpen;
         $this->intervention = new ImageManager(['driver' => $driver]);
     }
 
@@ -115,8 +101,7 @@ public function extract(array $samples) : array
                     $image = $image->greyscale();
                 }
 
-                $image->fit(...$this->size)
-                    ->sharpen($this->sharpen);
+                $image->fit(...$this->size);
 
                 $vectors[] = $this->vectorize($image);
             }
@@ -139,11 +124,11 @@ public function vectorize(Image $image) : array
 
         for ($x = 0; $x < $this->size[0]; $x++) {
             for ($y = 0; $y < $this->size[1]; $y++) {
-                $rgba = imagecolorsforindex($image,
-                    imagecolorat($image, $x, $y));
+                $rgba = imagecolorsforindex($image, imagecolorat($image, $x, $y));
 
-                $vector = array_merge($vector,
-                    array_values(array_slice($rgba, 0, $this->channels)));
+                foreach (array_slice($rgba, 0, $this->channels) as $value) {
+                    $vector[] = $value;
+                };
             }
         }
 

tests/Extractors/PixelEncoderTest.php renamed to tests/Extractors/RawPixelEncoderTest.php

@@ -3,10 +3,10 @@
 namespace Rubix\Tests\Extractors;
 
 use Rubix\ML\Extractors\Extractor;
-use Rubix\ML\Extractors\PixelEncoder;
+use Rubix\ML\Extractors\RawPixelEncoder;
 use PHPUnit\Framework\TestCase;
 
-class PixelEncoderTest extends TestCase
+class RawPixelEncoderTest extends TestCase
 {
     protected $extractor;
 
@@ -18,12 +18,12 @@ public function setUp()
             imagecreatefromjpeg(__DIR__ . '/space.jpg'),
         ];
 
-        $this->extractor = new PixelEncoder([3, 3], true, 0, 'gd');
+        $this->extractor = new RawPixelEncoder([3, 3], true, 'gd');
     }
 
     public function test_build_count_vectorizer()
     {
-        $this->assertInstanceOf(PixelEncoder::class, $this->extractor);
+        $this->assertInstanceOf(RawPixelEncoder::class, $this->extractor);
         $this->assertInstanceOf(Extractor::class, $this->extractor);
     }