Android中图片处理

来源：互联网发布：伍华聪开发框架源码编辑：程序博客网时间：2024/05/24 02:50

加载图片

加载大图: 3648 * 2736

总像素的个数: 9980928每一个像素占用的空间: ARGB_4444(2bytes), ARGB_8888(4bytes), RGB_565(2bytes)图片占用的空间 = 总像素的个数 * 像素的单位.9980928 * 2bytes = 19961856bytes = 19.037109375MB

缩放加载.

图片的宽和高: 3648 * 2736
屏幕的宽和高: 320 * 480
计算缩放比例
- 宽度缩放比例: 3648 / 320 = 11;
- 高度缩放比例: 2736 / 480 = 5;
- 比较宽和高的缩放比例, 哪一个大用哪一个进行缩放.

进行缩放: 331 * 248 = 82088 * 2bytes = 164176bytes = 160KB

3648 / 11 = 331; 2736 / 11 = 248;

核心代码：String picpath = et_picpath.getText().toString().trim();Options opts = new Options();opts.inJustDecodeBounds = true;BitmapFactory.decodeFile(picpath, opts);int picHeight = opts.outHeight;int picWidth = opts.outWidth;WindowManager manager = getWindowManager();int screenHeight = manager.getDefaultDisplay().getHeight();int screenWidth = manager.getDefaultDisplay().getWidth();int heightScale = picHeight / screenHeight;int widthScale = picWidth / screenWidth;int scale = heightScale > widthScale ? heightScale : widthScale;opts.inJustDecodeBounds = false;opts.inSampleSize = scale;Bitmap bitmap = BitmapFactory.decodeFile(picpath, opts);iv_image.setImageBitmap(bitmap);

0 0