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C# Win8: copy .PNG to the Windows clipboard; paste with transparency preserved

I have been tasked with capturing an image, copy it to the clipboard, and paste it to the application below. I must be able to support pretty much any rich text field, and it must preserve transparency. My current solution first renders a white background. Here is my code:
The RenderTargetBitmap contains the image that I wish to copy as a .PNG
public static void CopyImageToClipboard(RenderTargetBitmap b)
{
MemoryStream stream = new MemoryStream();
PngBitmapEncoder encoder = new PngBitmapEncoder();
encoder.Frames.Add(BitmapFrame.Create(b));
encoder.Save(stream);
Bitmap bmp = new Bitmap(stream);
Bitmap blank = new Bitmap(Convert.ToInt32(b.Width), Convert.ToInt32(b.Height));
Graphics g = Graphics.FromImage(blank);
g.Clear(System.Drawing.Color.White);
System.Drawing.Image img = System.Drawing.Image.FromStream(stream);
g.DrawImage(img, 0, 0, Convert.ToInt32(b.Width), Convert.ToInt32(b.Height));
Bitmap tempImage = new Bitmap(blank);
blank.Dispose();
img.Dispose();
bmp = new Bitmap(tempImage);
tempImage.Dispose();
System.Windows.Forms.Clipboard.SetImage(bmp);
stream.Dispose();
}

Just pick a random color to use it as background, let's say
var background = Color.FromArgb(1, 255, 1, 255);
Erase background to it:
g.Clear(background); // instead of System.Drawing.Color.White
Then make that color transparent:
Bitmap tempImage = new Bitmap(blank);
tempImage.MakeTransparent(background);
Note that also default transparent color works pretty well, no need to pick a magic color (check if you need to Clear() background, it may be - I didn't check - default bitmap background):
g.Clear(Color.Transparent);
// ...
tempImage.MakeTransparent();
EDIT Some older RTF control versions won't handle transparency and there is nothing (AFAIK) you can do for it. A half decent workaround (if you can't detect control class of paste target and read its background color) is to use Color.FromArgb(254, 255, 255, 255). White where transparency isn't supported and...completely transparent (because of MakeTransparent()) where it is.

The Windows clipboard, by default, does not support transparency, but you can put content on the clipboard in many types together to make sure most applications find some type in it that they can use. Generally, if, in addition to the normal nontransparent clipboard Bitmap format, you put the image on the clipboard in both PNG and DIB formats, most applications will be able to use at least one of them to get the image in a format they support as being transparent.
These formats are put on the clipboard in a specific way, though. They need to have their data (for png, that's not the loaded image object but the actual png file's bytes) put in a MemoryStream that is then put on the clipboard.
PNG put on the clipboard like that will be accepted by a multitude of applications, including Gimp and the newer MS Office. And of course, if you implement reading for it too, you can use it in your own application. The (rather dirty) DIB format should take care of most other applications, if they indeed support transparent image pasting at all.
I detailed how to do both the copying and the retrieving in this answer:
https://stackoverflow.com/a/46424800/395685

32bit rgb bmp to 24bit rgb bmp in C# problem

I have to convert 32bit rgb bmp images in to 24 bits rgb bmp.
This is what i am trying to do
Bitmap b1=new Bitmap(sorecFileName);
Bitmap b2=new
Bitmap(b1.Size.Width,b1.Size.Height,System.Drawing.Imaging.PixelFormat.Format24bppRgb);
b2.SetResolution(b1.HorizontalResolution, b1.VerticalResolution);
Graphics g=Graphics.FromImage(b2);
g.DrawImage(b1,0,0);
//continue to draw on g here to add text or graphics.
g.Dispose();
b2.Save(destinationFileName);
The code compiles fine and generates the output image of 24bpp but its not in the rgb format any more. Why is this so?
I figured it out as I have a library that takes input of an image as rgb24 and displays it. So when I try to give the file generated by above code as input to the function, it displays noisy image.
However, if I open the same file in paint and save it as 24bpp bmp, and input it to the function, the picture displays fine. What am I missing?

b2.Save(destinationFileName);
You didn't specify the image file format. The default is PNG, not BMP. You now probably have a .bmp file on disk that actually contains a PNG image. That can go undetected for quite a while, lots of graphics programs pay attention to the file header instead of the file name extension. MSPaint for example will have no trouble loading the file. Just like any other program that uses GDI+. You might not be so lucky with a program that blindly assumes that the file contains a BMP and does no checking at all. Fix:
b2.Save(destinationFilename, System.Drawing.Imaging.ImageFormat.Bmp);

if you got a blackimage -
Add g.Clear(Color.White);

C# resize, resave .tif as .jpg gives a blue tint to the new image

I'm building a batch processor to save a directory of .tif images as .jpgs. The processing is working fine. However, the rendered jpgs have a blue-ish tint to them. They aren't "blue", as much as they have a cooler hue, a blue hue. The originals are much brighter and warmer in color. This is how I am creating the resized jpeg:
Bitmap bitmap = new Bitmap(image.Image, size);
Graphics graphics = Graphics.FromImage(bitmap);
graphics.InterpolationMode = System.Drawing.Drawing2D.InterpolationMode.HighQualityBicubic;
graphics.SmoothingMode = System.Drawing.Drawing2D.SmoothingMode.HighQuality;
graphics.PixelOffsetMode = System.Drawing.Drawing2D.PixelOffsetMode.None;
graphics.DrawImage(image.Image, 0, 0, size.Width, size.Height);
// Get EncoderInfo("image/jpeg") gets the jpeg Codec by mime type
bitmap.Save(path, GetEncoderInfo("image/jpeg"), EncoderParameters);
The original tif images are 7MB is size - large in comparison to the rendered jpegs. Perhaps that has something to do with it. Not sure.
I've come up empty on the Googles. Does anyone have any experience with this or any advice on what to try next? Thanks!

It could be that the original files have a color profile. In that case, you need to copy that information into the new file as well. I don't know how to do that with .NET's imaging classes.

I would first suggest a test:
Create a plain image with a single colour.
Convert it to jpeg.
Then check in a photo package if the hue has actually changed or if it is your perception.

From the MSDN documentation, it looks like you can be doing this somewhat simpler (assuming image.Image is an actual System.Drawing.Image instance):
image.Image.Save(path, System.Drawing.ImageFormat.Jpeg)
That might help - it looks like you're taking your TIF, converting to a bitmap, and only then converting to a JPG.

Convert WriteableBitmap pixel format to Bgra32 in c# wpf

I have a WriteableBitmap which loads the bitmap image from file(mostly bmp). The bitmap files I am using have different pixel formats such as Indexed8, Bgra32, etc etc. The problem is that my code only works for bgra32 pixel format. So I need help in converting the bitmaps to Bgra32 pixel format in c# wpf.
Thanks

I have found the solution:
if (bmpSource.Format != PixelFormats.Bgra32)
bmpSource = new FormatConvertedBitmap(bmpSource, PixelFormats.Bgra32, null, 0);

How to render images in real-time

I am looking for a solution\software that I can use in order to render buttons in real time.
That is, I have an image and text, and I want them to be an image altogether in realtime.
Thank you

You can dynamically create an image based on text using the System.Drawing namespace.
private Bitmap CreateBitmapImage(string imageText, string imageUrl)
{
Bitmap myBitmap = new Bitmap(imageUrl);
Graphics g = Graphics.FromImage(myBitmap);
g.DrawString(imageText, new Font("Tahoma", 40), Brushes.White, new PointF(0, 0));
return (objBmpImage);
}
Once you have the Bitmap object in memory you can save it to the disk and call it's location from the web.
Bitmap bmp = CreateBitmapImage("my picture", #"C:\myBasePic.bmp");
bmp.Save(#"C:\bla.png", System.Drawing.Imaging.ImageFormat.png);

It would be good if you can specify why such requirement is there. One of such scenario that I had encountered was need of image buttons with different text (round corners with shaded background) - this can easily be achieved using CSS. If you really want to combine an image and text together then you can do that at server side (using say System.Drawing types) and serve the combined image over a handler/web-service.