Java实现图片比对(2)-逐像素对比

图片对比的另一种方式是通过将图片每一个像素的RGB值提取出来，然后比较两个图片每一个像素的RGB值；该方法的问题是速度比较慢，需要消耗较大的空间；

private static InputStream getImageStreamFromWeb(String urlAddress) {
		URL url = null;
		HttpURLConnection conn = null;
		try {
			url = new URL(urlAddress);
			conn = (HttpURLConnection) url.openConnection();
			if (conn.getResponseCode() == 200) {
				InputStream in = conn.getInputStream();
				return in;
			} else {
				throw new PictureNotFoundError("can not found #ADD# picture: "
						+ urlAddress);
			}
		} catch (Exception e) {
		}
		return null;
	}

public static String[][] getPX(InputStream in) {
		int[] rgb = new int[3];

		BufferedImage bi = null;
		try {
			bi = ImageIO.read(in);
		} catch (Exception e) {
			e.printStackTrace();
		}

		int width = bi.getWidth();
		int height = bi.getHeight();
		int minx = bi.getMinX();
		int miny = bi.getMinY();
		String[][] list = new String[width][height];
		for (int i = minx; i < width; i++) {
			for (int j = miny; j < height; j++) {
				int pixel = bi.getRGB(i, j);
				rgb[0] = (pixel & 0xff0000) >> 16;
				rgb[1] = (pixel & 0xff00) >> 8;
				rgb[2] = (pixel & 0xff);
				list[i][j] = rgb[0] + "," + rgb[1] + "," + rgb[2];
			}
		}
		rgb = null;
		return list;

	}

public static boolean compareImage(InputStream img1, InputStream img2) {
		// 分析图片相似度 begin
		String[][] list1 = getPX(img1);
		String[][] list2 = getPX(img2);
		int xiangsi = 0;
		int busi = 0;
		int i = 0, j = 0;
		for (String[] strings : list1) {
			if ((i + 1) == list1.length) {
				continue;
			}
			for (int m = 0; m < strings.length; m++) {
				try {
					String[] value1 = list1[i][j].toString().split(",");
					String[] value2 = list2[i][j].toString().split(",");
					int k = 0;
					for (int n = 0; n < value2.length; n++) {
						if (Math.abs(Integer.parseInt(value1[k])
								- Integer.parseInt(value2[k])) < 5) {
							xiangsi++;
						} else {
							busi++;
						}
					}
				} catch (RuntimeException e) {
					continue;
				}
				j++;
			}
			i++;
		}

		list1 = list2;
		list2 = list1;
		i = 0;
		j = 0;
		for (String[] strings : list1) {
			if ((i + 1) == list1.length) {
				continue;
			}
			for (int m = 0; m < strings.length; m++) {
				try {
					String[] value1 = list1[i][j].toString().split(",");
					String[] value2 = list2[i][j].toString().split(",");
					int k = 0;
					for (int n = 0; n < value2.length; n++) {
						if (Math.abs(Integer.parseInt(value1[k])
								- Integer.parseInt(value2[k])) < 5) {
							xiangsi++;
						} else {
							busi++;
						}
					}
				} catch (RuntimeException e) {
					continue;
				}
				j++;
			}
			i++;
		}
		String baifen = "";
		try {
			baifen = ((Double.parseDouble(xiangsi + "") / Double
					.parseDouble((busi + xiangsi) + "")) + "");
			baifen = baifen.substring(baifen.indexOf(".") + 1, baifen
					.indexOf(".") + 3);
		} catch (Exception e) {
			baifen = "0";
		}
		if (baifen.length() <= 0) {
			baifen = "0";
		}
		if (busi == 0) {
			baifen = "100";
		}
		
		list1 = null;
		list2 = null;
		
		if (!baifen.equals("100")) {
			return false;
		} else {
			return true;
		}

	}