java - 将位图转换为字节数组，反之亦然

Question

在我的 android 应用程序中，我想将从相机拍摄的图像转换为字节数组并转换回位图以在图像视图中查看。我可以通过 Bitmap.compress 轻松完成。但我想在没有 Bitmap.compress 的情况下做到这一点。问题是我得到白线（每次图像都很差（线））

                        Bitmap hello;    //image coming from camera
                        ByteBuffer buffer = ByteBuffer.allocate(hello.getByteCount()); 
                        hello.copyPixelsToBuffer(buffer);
                        byte[] bytes1 = buffer.array();
                        byte [] Bits = new byte[bytes1.length*4];
                        int i;
                   for(i=0;i<bytes1.length;i++)
                {
                    Bits[i*4] =
                        Bits[i*4+1] =
                        Bits[i*4+2] = (byte) ~bytes1[i]; //Invert the source bits
                    Bits[i*4+3] = -1;//0xff, that's the alpha.
                }

                Bitmap bmimage = Bitmap.createBitmap( 360,248, Bitmap.Config.ARGB_8888);
                bmimage.copyPixelsFromBuffer(ByteBuffer.wrap(Bits));
                imageView11.setImageBitmap(bmimage);

Answer 1

位图到字节数组：

ByteArrayOutputStream stream = new ByteArrayOutputStream();
bmp.compress(Bitmap.CompressFormat.PNG, 100, stream);
byte[] imageBytes = stream.toByteArray();

或者

int bytes = bitmap.getByteCount();
ByteBuffer buffer = ByteBuffer.allocate(bytes); 
bitmap.copyPixelsToBuffer(buffer); 
byte[] array = buffer.array();

字节数组到位图：

 InputStream inputStream = new ByteArrayInputStream(bytes);
  BitmapFactory.Options o = new BitmapFactory.Options();
  BitmapFactory.decodeStream(inputStream, null, o);

Answer 2

    ByteArrayOutputStream baos = new ByteArrayOutputStream();  
    bm.compress(Bitmap.CompressFormat.PNG, 100, baos); //bm is the bitmap object   
    byte[] b = baos.toByteArray();
    ///useing following code 
    String encoded = Base64.encodeToString(b, Base64.DEFAULT);