3

I have a C++ QT application that is sending a ByteArray of ARGB values via a TCP socket. The image is 100 x 100. The problem is that when I read off the ByteArray I can't seem to get the image to display right. I've tried lots of different ways and here is AS3 code that's got me the closest.

bitmapData.lock();
for(var x = 0;x<100; x++){
  for(var y = 0;y<100; y++){
    alphaValue = byteArray.readUnsignedByte();
    redValue = byteArray.readUnsignedByte();
    greenValue = byteArray.readUnsignedByte();
    blueValue = byteArray.readUnsignedByte();
    color = redValue << 16 | greenValue << 8 | blueValue;
    bitmapData.setPixel(y,x,color);
  }
}
bitmapData.unlock();

I'm just not using the alpha value at the moment because I'm not sure what to do with it. Qt says "The image is stored using a 32-bit RGB format (0xffRRGGBB)." I tried using readUnsignedInt() too, but that didn't work either.

Here is what I'm trying to send and what I see on screen.

Sent : enter image description here Received in Flash enter image description here

It's close, but not just right. Does anyone have any idea what I may be doing wrong?

dda
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Ben
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1 Answers1

4

Much easier would be to use readUnsignedInt instead of multiple calls to readByte. Then use bitmap.setPixel32 instead of setPixel. That way you don't have to deconstruct and reconstruct the values.

You might also have to switch the endian-ness (e.g. byteArray.endian = Endian.LITTLE_ENDIAN) depending on how it's encoded. I just can't remember off-hand which way around it is, so you can try that if it doesn't work first time.

Peter Hall
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  • I had tried readUnsignedInt with setPixel32 and had similar looking issues. I haven't tried changing to LITTLE_ENDIAN though, I'll try that and get back to you. Thanks. – Ben Jul 21 '12 at 15:21
  • byteArray.endian = Endian.LITTLE_ENDIAN; Worked perfectly can't say how good it feels after trying all sorts for hours. Not a lot of info on the endian stuff in documentation, I've done some reading and understand it a bit more now. Thanks. – Ben Jul 21 '12 at 16:23