Comments

001  import java.util.HashMap;
002  import java.awt.image.BufferedImage;
003  
004  /**
005   * Represents an image buffer that stores pixel data in a 2D array format.
006   * This class provides methods to access and manipulate the pixel data of an
007   * image.
008   */
009  class ImageBuffer {
010      private final long[][] pixels;
011      private final int width;
012      private final int height;
013  
014      /**
015       * Initializes a Buffer using an existing {@link BufferedImage}.
016       * This constructor extracts the pixel data from the provided BufferedImage.
017       *
018       * @param image The BufferedImage to be stored in this buffer.
019       *              This image's pixel data will be copied to the internal storage.
020       */
021      public ImageBuffer(BufferedImage image) {
022          width = image.getWidth();
023          height = image.getHeight();
024          pixels = new long[width][height];
025  
026          for (int x = 0; x < width; x++) {
027              for (int y = 0; y < height; y++) {
028                  pixels[x][y] = image.getRGB(x, y);
029              }
030          }
031      }
032  
033      /**
034       * Initializes an empty Buffer with the specified dimensions.
035       * The pixel data will not be initialized and will default to zero.
036       *
037       * @param width  The width of the image to be created.
038       * @param height The height of the image to be created.
039       */
040      public ImageBuffer(int width, int height) {
041          this.width = width;
042          this.height = height;
043          pixels = new long[width][height];
044      }
045  
046      /**
047       * Retrieves the RGB value of a pixel at the specified coordinates.
048       *
049       * @param x The x-coordinate of the pixel (horizontal position).
050       * @param y The y-coordinate of the pixel (vertical position).
051       * @return The RGB value of the pixel at the specified coordinates.
052       * @throws IllegalArgumentException if the specified coordinates are out of
053       *                                  bounds.
054       */
055      public long getRGB(int x, int y) {
056          if (x >= 0 && x < width && y >= 0 && y < height) {
057              return pixels[x][y];
058          } else {
059              throw new IllegalArgumentException("Coordinates out of bounds");
060          }
061      }
062  
063      /**
064       * Sets the RGB value of a pixel at the specified coordinates.
065       *
066       * @param x     The x-coordinate of the pixel (horizontal position).
067       * @param y     The y-coordinate of the pixel (vertical position).
068       * @param pixel The RGB value to be set for the pixel.
069       * @throws IllegalArgumentException if the specified coordinates are out of
070       *                                  bounds.
071       */
072      public void setRGB(int x, int y, long pixel) {
073          if (x >= 0 && x < width && y >= 0 && y < height) {
074              pixels[x][y] = pixel;
075          } else {
076              throw new IllegalArgumentException("Coordinates out of bounds");
077          }
078      }
079  
080      /**
081       * Returns the width of the image.
082       *
083       * @return The width of the image in pixels.
084       */
085      public int getWidth() {
086          return width;
087      }
088  
089      /**
090       * Returns the height of the image.
091       *
092       * @return The height of the image in pixels.
093       */
094      public int getHeight() {
095          return height;
096      }
097  }
098  
099  /**
100   * Provides the method to alter image brightness
101   */
102  class ImageModel {
103      private final HashMap<String, ImageBuffer> loadedImages; // A map to store loaded images by name
104  
105      public ImageModel() {
106          this.loadedImages = new HashMap<>();
107      }
108  
109      public ImageBuffer getImage(String name) {
110          return loadedImages.get(name);
111      }
112  
113      public void setImage(String key, ImageBuffer image) {
114          loadedImages.put(key, image);
115      }
116  
117      // Helper method to clamp values between 0 and 255 (valid RGB values)
118      private long clamp(long value) {
119          return Math.min(255, Math.max(0, value));
120      }
121  
122      /**
123       * Alters the brightness of the specified image.
124       * Each pixel's RGB value is adjusted by a specified brightness factor.
125       *
126       * @param image      The original image to be brightened.
127       * @param brightness The amount to adjust the brightness. Positive values
128       *                   increase brightness, while negative values decrease it.
129       * @return A new Buffer containing the brightened image.
130       */
131      public ImageBuffer alterBrightness(ImageBuffer image, float brightness) {
132          int width = image.getWidth();
133          int height = image.getHeight();
134  
135          // Create a new Buffer to store the modified image
136          ImageBuffer brightenedImage = new ImageBuffer(width, height);
137  
138          // Loop over every pixel in the image
139          for (int y = 0; y < height; y++) {
140              for (int x = 0; x < width; x++) {
141                  // Get the current pixel's RGB value
142                  long rgb = image.getRGB(x, y);
143  
144                  // Extract the red, green, and blue components using bitwise operations
145                  long red = (rgb >> 16) & 0xFF;
146                  long green = (rgb >> 8) & 0xFF;
147                  long blue = rgb & 0xFF;
148  
149                  // Adjust brightness by adding to each color component
150                  red = clamp((int) (red + brightness));
151                  green = clamp((int) (green + brightness));
152                  blue = clamp((int) (blue + brightness));
153  
154                  // Recombine the adjusted RGB components into a single int
155                  long newRGB = (red << 16) | (green << 8) | blue;
156  
157                  // Set the new RGB value in the brightened image
158                  brightenedImage.setRGB(x, y, newRGB);
159              }
160          }
161  
162          return brightenedImage;
163      }
164  
165  }