图片转字符画，GIF动画转GIF字符动画

里面用到的三个工具类可以自行网上搜索。

转换原理是取每像素的RGB值转换成灰度值，映射到各个字符中。

public class ImageToChar {

	static String ascii = "$@B%8&WM#*oahkbdpqwmZO0QLCJUYXzcvunxrjft/\\|()1{}[]?-_+~<>i!lI;:,\\\"^`'.";

	public static char toChar(int g) {
		if (g <= 30) {
			return '#';
		} else if (g > 30 && g <= 60) {
			return '&';
		} else if (g > 60 && g <= 120) {
			return '$';
		} else if (g > 120 && g <= 150) {
			return '*';
		} else if (g > 150 && g <= 180) {
			return 'o';
		} else if (g > 180 && g <= 210) {
			return '!';
		} else if (g > 210 && g <= 240) {
			return ';';
		} else {
			return ' ';
		}
	}

	public static void load(String imagePath, String txtPath) throws IOException {
		BufferedImage bi = null;
		File imageFile = new File(imagePath);
		bi = ImageIO.read(imageFile);
		load(bi, txtPath);
	}

	public static void load(BufferedImage bi, String txtPath) throws IOException {
		File txtFile = new File(txtPath);
		if (!txtFile.exists()) {
			txtFile.getParentFile().mkdirs();
			txtFile.createNewFile();
		}
		BufferedWriter bufferedWriter = new BufferedWriter(new OutputStreamWriter(new FileOutputStream(txtFile)));
		int width = bi.getWidth();
		int height = bi.getHeight();
		int minx = bi.getMinX();
		int miny = bi.getMinY();
		System.out.println(width + " " + height);
		for (int i = miny; i < height; i += 8) {
			for (int j = minx; j < width; j += 8) {
				int pixel = bi.getRGB(j, i); // 下面三行代码将一个数字转换为RGB数字
				int red = (pixel & 0xff0000) >> 16;
				int green = (pixel & 0xff00) >> 8;
				int blue = (pixel & 0xff);
				double gray = 0.299 * red + 0.578 * green + 0.114 * blue;
				// char c = ascii.charAt((int) (gray / 255 * ascii.length()));
				char c = toChar((int) gray);
				bufferedWriter.write(c);
			}
			bufferedWriter.newLine();
		}
		bufferedWriter.flush();
		bufferedWriter.close();
	}

	public static void loadGif(String imagePath, String outPath) throws IOException {
		File imageFile = new File(imagePath);
		FileImageInputStream in = new FileImageInputStream(imageFile);
		ImageReaderSpi readerSpi = new GIFImageReaderSpi();
		GIFImageReader gifImageReader = new GIFImageReader(readerSpi);
		gifImageReader.setInput(in);
		int num = gifImageReader.getNumImages(true);
		System.out.println(num);
		BufferedImage[] bufferedImages = new BufferedImage[num];
		for (int i = 0; i < num; i++) {
			BufferedImage bi = gifImageReader.read(i);
			bufferedImages[i] = txtToImage(bi, outPath + "out" + i + ".jpeg");
		}
		jpgToGif(bufferedImages, outPath + imagePath.substring(imagePath.length() - 6) + "outGif.gif", 100);
	}

	public static BufferedImage txtToImage(BufferedImage bi, String outPutPath) {
		File imageFile = new File(outPutPath);
		if (!imageFile.exists()) {
			try {
				imageFile.createNewFile();
			} catch (IOException e) {
				e.printStackTrace();
			}
		}

		int width = bi.getWidth();
		int height = bi.getHeight();
		int minx = bi.getMinX();
		int miny = bi.getMinY();
		System.out.println(width + " " + height);
		int speed = 7;
		BufferedImage bufferedImage = new BufferedImage(width, height, BufferedImage.TYPE_INT_RGB);
		// 获取图像上下文
		Graphics g = createGraphics(bufferedImage, width, height, speed);
		// 图片中文本行高
		final int Y_LINEHEIGHT = speed;
		int lineNum = 1;
		for (int i = miny; i < height; i += speed) {
			// StringBuilder stringBuilder = new StringBuilder();
			for (int j = minx; j < width; j += speed) {
				int pixel = bi.getRGB(j, i); // 下面三行代码将一个数字转换为RGB数字
				int red = (pixel & 0xff0000) >> 16;
				int green = (pixel & 0xff00) >> 8;
				int blue = (pixel & 0xff);
				double gray = 0.299 * red + 0.578 * green + 0.114 * blue;
				// char c = ascii.charAt((int) (gray / 255 * ascii.length()));
				char c = toChar((int) gray);
				// stringBuilder.append(c);
				g.drawString(String.valueOf(c), j, i);
			}
			// g.drawString(stringBuilder.toString(), 0, lineNum * Y_LINEHEIGHT);
			lineNum++;
		}
		g.dispose();
		// 保存为jpg图片
		FileOutputStream fos;
		try {
			fos = new FileOutputStream(imageFile);
			JPEGImageEncoder encoder = JPEGCodec.createJPEGEncoder(fos);
			encoder.encode(bufferedImage);
			fos.close();
		} catch (FileNotFoundException e) {
			e.printStackTrace();
		} catch (ImageFormatException e) {
			e.printStackTrace();
		} catch (IOException e) {
			e.printStackTrace();
		}
		return bufferedImage;

	}

	private static void jpgToGif(BufferedImage[] bufferedImages, String newPic, int playTime) {
		try {
			AnimatedGifEncoder e = new AnimatedGifEncoder();
			e.setRepeat(0);
			e.start(newPic);
			for (int i = 0; i < bufferedImages.length; i++) {
				e.setDelay(playTime); // 设置播放的延迟时间
				e.addFrame(bufferedImages[i]); // 添加到帧中
			}
			e.finish();
		} catch (Exception e) {
			System.out.println("jpgToGif Failed:");
			e.printStackTrace();
		}
	}

	private static Graphics createGraphics(BufferedImage image, int width, int height, int size) {
		Graphics g = image.createGraphics();
		g.setColor(null); // 设置背景色
		g.fillRect(0, 0, width, height);// 绘制背景
		g.setColor(Color.BLACK); // 设置前景色
		g.setFont(new Font("微软雅黑", Font.PLAIN, size)); // 设置字体
		return g;
	}

	public static void main(String[] args) throws IOException {
		// load("C:\\Users\\lenovo\\Desktop\\2.jpg", "f:/charImage/1.txt");
		loadGif("F:\\gif\\test4.gif", "f:/gif/");
		// loadGif("F:\\charImage\\1.gif", "f:/gif/");
	}