/// <summary>
/// Saves the given Frame into a stream
/// </summary>
/// <param name="frame">The frame to write to the stream</param>
/// <param name="stream">The stream to write the frame to</param>
protected void SaveFrameToStream(IFrame frame, Stream stream)
{
BinaryWriter writer = new BinaryWriter(stream);
var castFrame = frame as Frame;
if (castFrame != null)
{
SaveLayersToStream(castFrame, stream);
}
else
{
using (Bitmap bitmap = frame.GetComposedBitmap())
{
PersistenceHelper.SaveImageToStream(bitmap, stream);
}
}
// Write the frame ID
writer.Write(frame.ID);
// Write the hash now
writer.Write(frame.Hash.Length);
writer.Write(frame.Hash, 0, frame.Hash.Length);
}
public void TestImagePersistence()
{
// Setup the test
Bitmap bitmap1 = FrameGenerator.GenerateRandomBitmap(48, 37, 0);
Bitmap bitmap2 = FrameGenerator.GenerateRandomBitmap(12, 45, 0);
Stream stream = new MemoryStream();
// Test the methods
PersistenceHelper.SaveImageToStream(bitmap1, stream);
PersistenceHelper.SaveImageToStream(bitmap2, stream);
// Reset stream
stream.Position = 0;
// Load the bitmaps back up again one at a time
Bitmap loadedBitmap1 = PersistenceHelper.LoadImageFromStream(stream);
Bitmap loadedBitmap2 = PersistenceHelper.LoadImageFromStream(stream);
// Compare images
Assert.IsTrue(ImageUtilities.ImagesAreIdentical(bitmap1, loadedBitmap1), "An image loaded from a stream must match completely the image that was saved");
Assert.IsTrue(ImageUtilities.ImagesAreIdentical(bitmap2, loadedBitmap2), "An image loaded from a stream must match completely the image that was saved");
// Try to edit the loaded bitmaps to verify editability
loadedBitmap1.SetPixel(0, 0, Color.Black);
loadedBitmap2.SetPixel(0, 0, Color.Black);
}
/// <summary>
/// Saves the contents of a layer to a stream
/// </summary>
/// <param name="layer">The layer to save</param>
/// <param name="stream">The stream to save the layer to</param>
private void SaveLayerToStream(IFrameLayer layer, Stream stream)
{
// Save the layer's name
BinaryWriter writer = new BinaryWriter(stream, Encoding.UTF8);
writer.Write(layer.Name);
PersistenceHelper.SaveImageToStream(layer.LayerBitmap, stream);
}