android 图片处理工具类，Bitmap转换String ,Drawable, byte[]，保存，优化等。

Posted 2022-11-30 IyangcLove

/**
 * 处理图片的工具类.
 */
public class ImageTools 
	/**
	 * 图片去色,返回灰度图片
	 * 
	 * @param bmpOriginal传入的图片
	 * @return 去色后的图片
	 */
	public static Bitmap toGrayscale(Bitmap bmpOriginal) 
		int width, height;
		// 获取宽高
		height = bmpOriginal.getHeight();
		width = bmpOriginal.getWidth();
		// 按照一定画质新建bitmap
		Bitmap bmpGrayscale = Bitmap.createBitmap(width, height,
				Bitmap.Config.RGB_565);
		// 建画布
		Canvas c = new Canvas(bmpGrayscale);
		// 建画笔
		Paint paint = new Paint();
		// 颜色矩阵
		ColorMatrix cm = new ColorMatrix();
		// 设置灰阶
		cm.setSaturation(0);
		// 颜色矩阵颜色过滤对象,传入设置的颜色矩阵
		ColorMatrixColorFilter f = new ColorMatrixColorFilter(cm);
		// 设置画笔的颜色过滤,传入颜色矩阵颜色过滤对象
		paint.setColorFilter(f);
		// 在画布用画笔画传入的图片
		c.drawBitmap(bmpOriginal, 0, 0, paint);
		return bmpGrayscale;
	
	/**
	 * 去色同时加圆角
	 * 
	 * @param bmpOriginal 原图
	 * @param pixels 圆角弧度
	 * @return 修改后的图片
	 */
	public static Bitmap toGrayscale(Bitmap bmpOriginal, int pixels) 
		return toRoundCorner(toGrayscale(bmpOriginal), pixels);
	
	/**
	 * 把图片变成圆角
	 * @param bitmap 需要修改的图片
	 * @param pixels 圆角的弧度
	 * @return 圆角图片
	 */
	public static Bitmap toRoundCorner(Bitmap bitmap, int pixels) 
		Bitmap output = Bitmap.createBitmap(bitmap.getWidth(),
				bitmap.getHeight(), Config.ARGB_8888);
		Canvas canvas = new Canvas(output);
		final int color = 0xff424242;
		final Paint paint = new Paint();
		final Rect rect = new Rect(0, 0, bitmap.getWidth(), bitmap.getHeight());
		final RectF rectF = new RectF(rect);

		final float roundPx = pixels;// 圆角的弧度

		paint.setAntiAlias(true);
		canvas.drawARGB(0, 0, 0, 0);
		paint.setColor(color);
		canvas.drawRoundRect(rectF, roundPx, roundPx, paint);
		paint.setXfermode(new PorterDuffXfermode(Mode.SRC_IN));
		canvas.drawBitmap(bitmap, rect, rect, paint);
		return output;
	
	/** */
	/**
	 * 使圆角功能支持BitampDrawable
	 * 
	 * @param bitmapDrawable  
	 * @param pixels
	 * @return
	 */
	public static BitmapDrawable toRoundCorner(BitmapDrawable bitmapDrawable,
			int pixels) 
		Bitmap bitmap = bitmapDrawable.getBitmap();
		bitmapDrawable = new BitmapDrawable(toRoundCorner(bitmap, pixels));
		return bitmapDrawable;
	
	/**
	 * 读取路径中的图片，然后将其转化为缩放后的bitmap
	 * @param path
	 */
	public static Bitmap saveBefore(String path) 
		BitmapFactory.Options options = new BitmapFactory.Options();
		options.inJustDecodeBounds = true;
		// 获取这个图片的宽和高
		Bitmap bitmap = BitmapFactory.decodeFile(path, options); // 此时返回bm为空
		options.inJustDecodeBounds = false;
		// 计算缩放比
		int be = (int) (options.outHeight / (float) 200);
		if (be <= 0) 
			be = 1;
		
		options.inSampleSize = 2; // 图片长宽各缩小二分之一
		// 重新读入图片，注意这次要把options.inJustDecodeBounds 设为 false哦
		bitmap = BitmapFactory.decodeFile(path, options);
		int w = bitmap.getWidth();
		int h = bitmap.getHeight();
		System.out.println(w + "    " + h);
		// savePNG_After(bitmap,path);
		saveJPGE_After(bitmap, path);
		return bitmap;
	
	/**
	 * 保存图片为PNG
	 * 
	 * @param bitmap bitmap对象
	 * @param name  path
	 */
	public static void savePNG_After(Bitmap bitmap, String name) 
		File file = new File(name);
		try 
			FileOutputStream out = new FileOutputStream(file);
			if (bitmap.compress(Bitmap.CompressFormat.PNG, 100, out)) 
				out.flush();
				out.close();
			
		 catch (FileNotFoundException e) 
			e.printStackTrace();
		 catch (IOException e) 
			e.printStackTrace();
		
	
	/**
	 * 保存图片为JPEG
	 * 
	 * @param bitmap
	 * @param path  
	 */
	public static void saveJPGE_After(Bitmap bitmap, String path) 
		File file = new File(path);
		try 
			FileOutputStream out = new FileOutputStream(file);
			if (bitmap.compress(Bitmap.CompressFormat.JPEG, 100, out)) 
				out.flush();
				out.close();
			
		 catch (FileNotFoundException e) 
			e.printStackTrace();
		 catch (IOException e) 
			e.printStackTrace();
		
	
	/**
	 * 水印
	 * 
	 * @param bitmap 图片
	 * @param bitmap 水印
	 * @return bitmap 处理后的图片
	 */
	public static Bitmap createBitmapForWatermark(Bitmap src, Bitmap watermark) 
		if (src == null) 
			return null;
		
		//位图的宽高
		int w = src.getWidth();
		int h = src.getHeight();
		//水印的宽高
		int ww = watermark.getWidth();
		int wh = watermark.getHeight();
		// 创建一个新的和SRC长度宽度一样的位图
		Bitmap newb = Bitmap.createBitmap(w, h, Config.ARGB_8888);
		Canvas cv = new Canvas(newb);
		// 在 0，0坐标开始画入src
		cv.drawBitmap(src, 0, 0, null);
		// 在src的右下角画入水印（距离底部和右边距离为5）
		cv.drawBitmap(watermark, w - ww + 5, h - wh + 5, null);
		// 保存
		cv.save(Canvas.ALL_SAVE_FLAG);
		// 存储
		cv.restore();
		return newb;
	
	/**
	 * 将Bitmap转换成指定大小
	 * 
	 * @param bitmap
	 * @param width
	 * @param height
	 * @return
	 */
	public static Bitmap createBitmapBySize(Bitmap bitmap, int width, int height) 
		return Bitmap.createScaledBitmap(bitmap, width, height, true);
	

	/**
	 * Drawable 转 Bitmap
	 * 
	 * @param drawable
	 * @return
	 */
	public static Bitmap drawableToBitmapByBD(Drawable drawable) 
		BitmapDrawable bitmapDrawable = (BitmapDrawable) drawable;
		return bitmapDrawable.getBitmap();
	
	/**
	 * Bitmap 转 Drawable
	 * 
	 * @param bitmap
	 * @return
	 */
	public static Drawable bitmapToDrawableByBD(Bitmap bitmap) 
		Drawable drawable = new BitmapDrawable(bitmap);
		return drawable;
	

	/**
	 * byte[] 转 bitmap
	 * 
	 * @param b
	 * @return
	 */
	public static Bitmap bytesToBimap(byte[] b) 
		if (b.length != 0) 
			return BitmapFactory.decodeByteArray(b, 0, b.length);
		 else 
			return null;
		
	
	/**
	 * bitmap 转 byte[]
	 * 
	 * @param bm
	 * @return
	 */
	public static byte[] bitmapToBytes(Bitmap bm) 
		ByteArrayOutputStream baos = new ByteArrayOutputStream();
		bm.compress(Bitmap.CompressFormat.PNG, 100, baos);
		return baos.toByteArray();
	
	
	/**  
     * 图片转成string  
     *   
     * @param bitmap  
     * @return  
     */  
    public static String convertIconToString(Bitmap bitmap)  
      
        ByteArrayOutputStream baos = new ByteArrayOutputStream();// outputstream  
        bitmap.compress(CompressFormat.PNG, 100, baos);  
        byte[] appicon = baos.toByteArray();// 转为byte数组  
        return Base64.encodeToString(appicon, Base64.DEFAULT);  
    
    /**  
     * string转成bitmap  
     *   
     * @param st  
     */  
    public static Bitmap convertStringToIcon(String st)  
      
        // OutputStream out;  
        Bitmap bitmap = null;  
        try  
          
            // out = new FileOutputStream("/sdcard/aa.jpg");  
            byte[] bitmapArray;  
            bitmapArray = Base64.decode(st, Base64.DEFAULT);  
            bitmap =  
                    BitmapFactory.decodeByteArray(bitmapArray, 0,  
                            bitmapArray.length);  
            // bitmap.compress(Bitmap.CompressFormat.PNG, 100, out);  
            return bitmap;  
          
        catch (Exception e)  
          
            return null;  
          
    
	
	/**
	 * Check the SD card 检测是否有SD卡
	 * 
	 * @return  
	 */
	public static boolean checkSDCardAvailable() 
		return android.os.Environment.getExternalStorageState().equals(
				android.os.Environment.MEDIA_MOUNTED);
	
	/**
	 * Save image to the SD card 保存图片到sd卡
	 * 
	 * @param photoBitmap 位图
	 * @param photoName  图片名
	 * @param path 存放路径
	 *            
	 */
	public static void savePhotoToSDCard(Bitmap photoBitmap, String path,
			String photoName) 
		// 判断是否存在sd卡
		if (checkSDCardAvailable()) 
			File dir = new File(path);
			// 如果dir 文件不存在,新建
			if (!dir.exists()) 
				dir.mkdirs();
			
			// 建图片文件路径,在文件路径下
			File photoFile = new File(path, photoName + ".png");
			// 新建文件输出流定为空
			FileOutputStream fileOutputStream = null;
			try 
				fileOutputStream = new FileOutputStream(photoFile);
				if (photoBitmap != null) 
					if (photoBitmap.compress(Bitmap.CompressFormat.PNG, 100,
							fileOutputStream)) 
						fileOutputStream.flush(); // 这里才是输出数据
						fileOutputStream.close();
					
				
			 catch (FileNotFoundException e) 
				photoFile.delete();
				e.printStackTrace();
			 catch (IOException e) 
				photoFile.delete();
				e.printStackTrace();
			 finally 
				try 
					fileOutputStream.close();
				 catch (IOException e) 
					e.printStackTrace();
				
			
		
	

 上传的这个工具类 是 网上找到的一些方法进行的一个总结，直接可以用的。 我现在都在用。代码中注释比较完整 就不用我再赘述了。