Getting Pixel Array From Image in Java (#13911)

* Added the code for "Getting Pixel Array From Image in Java". * The code and resources for "Getting Pixel Array From Image in Java". * Removed the previous files from the wrong module.
2023-04-27 02:52:53 +03:00
parent e3cc8abadb
commit 01c02e151e
2 changed files with 95 additions and 0 deletions
@@ -0,0 +1,65 @@
+package com.baeldung.algorithms.pixelarray;
+
+import java.awt.image.BufferedImage;
+import java.awt.image.DataBufferByte;
+public class GetPixelArray {
+
+    public static int[][] get2DPixelArraySlow(BufferedImage sampleImage) {
+        int width = sampleImage.getWidth();
+        int height = sampleImage.getHeight();
+        int[][] result = new int[height][width];
+
+        for (int row = 0; row < height; row++) {
+            for (int col = 0; col < width; col++) {
+                result[row][col] = sampleImage.getRGB(col, row);
+            }
+        }
+
+        return result;
+    }
+
+    public static int[][] get2DPixelArrayFast(BufferedImage image) {
+        final byte[] pixelData = ((DataBufferByte) image.getRaster().getDataBuffer()).getData();
+        final int width = image.getWidth();
+        final int height = image.getHeight();
+        final boolean hasAlphaChannel = image.getAlphaRaster() != null;
+
+        int[][] result = new int[height][width];
+        if (hasAlphaChannel) {
+            final int numberOfValues = 4;
+            for (int valueIndex = 0, row = 0, col = 0; valueIndex + numberOfValues - 1 < pixelData.length; valueIndex += numberOfValues) {
+                // Getting the values for each pixel from the pixelData array.
+                int argb = 0;
+                argb += (((int) pixelData[valueIndex] & 0xff) << 24); // alpha value
+                argb += ((int) pixelData[valueIndex + 1] & 0xff); // blue value
+                argb += (((int) pixelData[valueIndex + 2] & 0xff) << 8); // green value
+                argb += (((int) pixelData[valueIndex + 3] & 0xff) << 16); // red value
+                result[row][col] = argb;
+
+                col++;
+                if (col == width) {
+                    col = 0;
+                    row++;
+                }
+            }
+        } else {
+            final int numberOfValues = 3;
+            for (int valueIndex = 0, row = 0, col = 0; valueIndex + numberOfValues - 1 < pixelData.length; valueIndex += numberOfValues) {
+                int argb = 0;
+                argb += -16777216; // 255 alpha value (fully opaque)
+                argb += ((int) pixelData[valueIndex] & 0xff); // blue value
+                argb += (((int) pixelData[valueIndex + 1] & 0xff) << 8); // green value
+                argb += (((int) pixelData[valueIndex + 2] & 0xff) << 16); // red value
+                result[row][col] = argb;
+
+                col++;
+                if (col == width) {
+                    col = 0;
+                    row++;
+                }
+            }
+        }
+
+        return result;
+    }
+}