gistfile1.cs

  	public byte[] Delta() {
			// Make a snapshot of the pixels in RGBA format.
			byte[] Snapshot = _Capturer.Snapshot();
			// Check if the previous snapshot is invalid.
			if (_PreviousSnapshot != null) {
				// Initialize a new instance of the MemoryStream class.
				using (MemoryStream MemoryStream = new MemoryStream()) {
					using (var zipper = new GZipStream(MemoryStream, CompressionLevel.Fastest)) {
						// Initialize a new instance of the BinaryWriter class.
						using (BinaryWriter BinaryWriter = new BinaryWriter(zipper)) {
							// Iterate through each pixel on each channel.
							for (int i = 0; i < Snapshot.Length; i += 4) {
								// Check if the pixel has changed a channel.
								if (Snapshot[i] != _PreviousSnapshot[i] || Snapshot[i + 1] != _PreviousSnapshot[i + 1] || Snapshot[i + 2] != _PreviousSnapshot[i + 2]) {
									// Write the pixel position.
									BinaryWriter.Write(i);
									// Write the red channel value.
									BinaryWriter.Write(Snapshot[i]);
									// Write the green channel value.
									BinaryWriter.Write(Snapshot[i + 1]);
									// Write the blue channel value.
									BinaryWriter.Write(Snapshot[i + 2]);
								}
							}
							// Check if a delta has been established.
							if (MemoryStream.Length != 0) {
								BinaryWriter.Flush();
								zipper.Flush();
								// Set the previous snapshot.
								_PreviousSnapshot = Snapshot;
								// Return the delta.
								return MemoryStream.ToArray();
							}
						}
					}
				}
			}
			// Set the previous snapshot.
			_PreviousSnapshot = Snapshot;
			// Return the delta.
			return null;
		}