Drawable, Bitmap, byte[]之间的转换

最新推荐文章于 2021-05-28 09:48:12 发布

转载最新推荐文章于 2021-05-28 09:48:12 发布 · 606 阅读

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本文介绍如何将Drawable转换为Bitmap，并从资源中获取Bitmap，同时提供Bitmap到byte[]和byte[]到Bitmap的转换方法。适用于Android开发中的图像处理需求。

1 Drawable → Bitmap

public static Bitmap drawableToBitmap(Drawable drawable) {

   Bitmap bitmap = Bitmap.createBitmap(drawable.getIntrinsicWidth(),
   drawable.getIntrinsicHeight(),
   drawable.getOpacity() != PixelFormat.OPAQUE ? Bitmap.Config.ARGB_8888
   : Bitmap.Config.RGB_565);
   Canvas canvas = new Canvas(bitmap);
   //canvas.setBitmap(bitmap);
   drawable.setBounds(0, 0, drawable.getIntrinsicWidth(), drawable.getIntrinsicHeight());
   drawable.draw(canvas);
   return bitmap;
}

public static Bitmap drawableToBitmap(Drawable drawable) {

   Bitmap bitmap = Bitmap.createBitmap(drawable.getIntrinsicWidth(),
   drawable.getIntrinsicHeight(),
   drawable.getOpacity() != PixelFormat.OPAQUE ? Bitmap.Config.ARGB_8888
   : Bitmap.Config.RGB_565);
   Canvas canvas = new Canvas(bitmap);
   //canvas.setBitmap(bitmap);
   drawable.setBounds(0, 0, drawable.getIntrinsicWidth(), drawable.getIntrinsicHeight());
   drawable.draw(canvas);
   return bitmap;
}

2 从资源中获取Bitmap

Resources res = getResources();
Bitmap bmp = BitmapFactory.decodeResource(res, R.drawable.pic);

3 Bitmap → byte[]

private byte[] Bitmap2Bytes(Bitmap bm) {
   ByteArrayOutputStream baos = new ByteArrayOutputStream();
   bm.compress(Bitmap.CompressFormat.PNG, 100, baos);
   return baos.toByteArray();
}

private byte[] Bitmap2Bytes(Bitmap bm) {
   ByteArrayOutputStream baos = new ByteArrayOutputStream();
   bm.compress(Bitmap.CompressFormat.PNG, 100, baos);
   return baos.toByteArray();
}

4 byte[] → Bitmap

private Bitmap Bytes2Bimap(byte[] b) {
   if (b.length != 0) {
   return BitmapFactory.decodeByteArray(b, 0, b.length);
   }
   else {
   return null;
   }
}

private Bitmap Bytes2Bimap(byte[] b) {
   if (b.length != 0) {
   return BitmapFactory.decodeByteArray(b, 0, b.length);
   }
   else {
   return null;
   }
}