* decode出来的所有图片不大于100k,实际上会是100k左右
* @param path
* @return
*/
public static Bitmap decodeBitmap(String path) {
Bitmap bitmap = null;
if(TextUtils.isEmpty(path)){
return null;
}
BitmapFactory.Options opts = new Options();
opts.inJustDecodeBounds = true;
bitmap = BitmapFactory.decodeFile(path, opts);
int sample = 1;
opts.inJustDecodeBounds = false;
opts.inPurgeable = true;
opts.inInputShareable = true;
// 每个像素点所占用的字节
int countPerPix = 0;
if("image/png".equalsIgnoreCase(opts.outMimeType)){
// png格式图片带透明通道
opts.inPreferredConfig = Config.ARGB_8888;
// ARGB_8888 一个像素占4个字节
countPerPix = 4;
}else{
// 其他图片格式不带透明通道，每个像素点不需要占用那么多字节
opts.inPreferredConfig = Config.RGB_565;
// 占两个字节
countPerPix = 2;
}
int width = opts.outWidth;
int height = opts.outHeight;
// 关键代码，100k=100*1024字节
while((width/sample)*(height/sample)*countPerPix>100*1024){sample++;
}
opts.inSampleSize =sample;
try {
bitmap = BitmapFactory.decodeStream(new FileInputStream(path), null, opts);
int size = bitmap.getRowBytes()*bitmap.getHeight()/1024;
Log.e("dream", "size="+size);
} catch (FileNotFoundException e) {
e.printStackTrace();
}
return bitmap;
}