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C# Fast load Bitmap into PictureBox

I receve Bitmap image from a camera at 30 fps, and I need to display all images in a pictureBox.
The problem is that the PictureBox is very slow!
I have try to implement a custom PictureBox with DoubleBuffer enabled but the problem is not resolved.
Do you have a custom PictureBox or an user control or a solution that can display the image faster?
Additional information:
The image resolution is 2048x1088 with 256 graylevel (8bit image).
I use AForge.NET for elaborate the images.
Thank you

That image gets expensive to draw when it has to be resized to fit the PB's client area. Which is very likely in your case because your images are pretty large. It uses a high-quality bi-cubic filter to make the resized image look good. That's pretty expensive, albeit that the result is good.
To avoid that expense, resize the image yourself before assigning it to the Image property. Make it just as large as the PB's ClientSize.
That's going to make a big difference in itself. The next thing you can do is to create the scaled bitmap with the 32bppPArgb pixel format. It's the format that's about 10 times faster then any other because it matches the video adapter on most machines so no pixel format conversions are necessary.

Why is WinForms drawing my image 4x the size?

I'm using WinForms to create a 512x512 px image with 96dpi resolution. After initialization, I use OnPaint to draw this image using Graphics.DrawImage. What I get as I run the program is the image shown below: essentially a 1024x1024 image which contains some jung vaguely resembling what I want to show, except it's made up of 2x2-pixel blocks all having uniformly identical colors. Which is weird.
Can someone help me figure out what is going on? This is only happening on high-DPI displays, the program works just fine on ordinary ones.
Update 1: I explicitly set the process to be DPI-unaware with SetProcessDpiAwareness(_Process_DPI_Awareness.Process_DPI_Unaware); and explicitly call DrawImage in a rectangle, i.e.,
e.Graphics.DrawImage(bmp,
new Rectangle(0, 0, 512, 512),
new Rectangle(0, 0, 512, 512), GraphicsUnit.Pixel);
and it did not help.
Edit 2: After turning DPI awareness on, I now get the same junk, but at the right size:
Edit 3: Finally got it, the artifacts were the results of my rendering things incorrectly on the CUDA side. The high-DPI nonsense was just a distraction.

This is only happening on high-DPI displays
That is entirely normal, you are seeing the image getting rescaled to match the DPI of the monitor. Which makes it bigger so the size in inches is the same.
The crude way to get this done is when you rely on DPI virtualization. Windows lets your program behave like it does on 96 DPI monitor, but gets it to draw into a bitmap. And rescales that bitmap to display it on the screen. Pretty crude, but your program is still usable, text quality suffers pretty noticeably.
The not-crude way is when you declared you program to be dpiAware. Now Windows no longer helps and it is Graphics.DrawImage() that takes care of the job. It by itself rescales the image to match the image DPI to the display DPI. Text looks very crisp. The image, meh, you have to move your chair back further.
If you don't want this rescaling to happen then you have to use the Graphics.DrawImage() overload that takes a Rectangle argument. But keep in mind that the image turns into a postage stamp on such a nice display. You'll have to move your chair closer :)

C# white or black unwanted pixels appear in the image

I am new to C#, I am using Visual Studo 2010, I have an image that needs to be displayed on a picturebox.
I tried many different methods. All the methods results in some unwanted pixels to appear along with image.
I have tried
picturebox.Image = Image.FromFile("bird.png");
result->
the image is displayed but with the stray white/black pixels at random places.
I also tried creating a bitmap of same size and drawing the image onto the bitmap and then assigning the bitmap to the picture box.Image. Still those unwanted pixels are visible.
I have tried clearing the picture box image (filling it with white or transparent) and then assigning the image, still same error occurs.
PS: this doesn't happen for all the images only certain images show this behaviour.
any help would be great
Code:
Image org = Bitmap.FromFile("bird.png");
Bitmap final = new Bitmap(org.Width,org.Height);
using (Graphics g = Graphics.FromImage(final))
{
g.DrawImage(org,0,0,GraphicsUnit.Pixel);
}
picturebox.Image = final;
if i use final.save("picture.png"). The "picuture.png" does not have that wrong pixels, it happens only when i use picture box to display it.
Please find the images attached defect orginal
PS: its not because of different fileformat (orginal and defect)

It was an TransperancyKey issue resolved by setting it to Default.

Images Scaling Down in draw in C#

Alright guys last little bit of this project I'll ask for help on I promise.
So I go to load the images, works fine however I notice upon loading that the dimensions of the image have been scaled down in the y to 300 (all are a constant value of 433) and up or down from their original width to 600.
I'm using the following method to load them
foreach (string file in Directory.EnumerateFiles(imagePath, "*.JPG"))
{
Image contents = Image.FromFile(file);
treesImage[count] = contents;
count++;
}
and this is the resulting image when I have it loaded.
http://i.stack.imgur.com/Q40kK.png
As you can see the image below the red rectangle is quite small
Any help would be appreciated. If you require any more information please post below and I'll make sure to edit the original question with the relevant information as soon as humanly possible.
EDIT: I am using a simple windows form application and not another graphical framework for my own reasons.
Thanks in advance :)

I'll assume you are using a PictureBox control to display the image.
When someone chooses a tree from your map, you obviously set the PictureBox Image property to the image object referenced by the index in the array. Use the Image object to set the ClientSize of the PictureBox control.
...
Image img = treesImage[idx];
MyPictureBox.SizeMode = PictureBoxSizeMode.Normal;
MyPictureBox.ClientSize = new Size(img.Width,img.Height);
MyPictureBox.Image = img;
...
Alternately you can define one size for your PictureBox and force all the images to be scaled to that size by setting the control SizeMode property to StretchImage declaratively.
I would recommend that you create a simple class (MyImageInfo for example) that would store the Path, Width, and Height of the images found in your first function into a list and then just as before when a user clicks to view an image you set the width and height of the PictureBox and then call the LoadAsync(path) method to get the image. then you aren't storing all images in memory at once, just as you need them since it doesn't look like this requires a lot of quick jumping from image to image.

How can I resize an image in C# while retaining high quality?

I found an article on image processing from here: http://www.switchonthecode.com/tutorials/csharp-tutorial-image-editing-saving-cropping-and-resizing Everything works fine.
I want to keep the high quality when resizing the image. I think if I can increase the DPI value I can achieve this. Does anyone know if this is possible? And if so, how can I implement it in C#?

For starters, it's worth pointing out that there are two general categories of images; vector [e.g. SVG, WMF, Adobe Illustrator and Corel Draw Graphics] and bitmap (also called raster) images [e.g. Bitmap, JPEG and PNG Images].
Vector images are formed from a series of mathematical equations and/or calculations. Bitmap images, on the other hand, are made up of individual dots (pixels) each corresponding to a particular feature on the object the image is taken of.
If it should happen that you want to resize an image, the first thing to consider is if it is a bitmap or vector image. By virtue of the fact that vector images are obtained from calculations, they can be perfectly resized without losing any detail. The case is different for bitmap images. Since each pixel is independent of the other, when you desire to resize it, you are simply increasing or decreasing the source to target pixel ratio.
So in order to double the size of a vector image, simply multiply the target dimensions by two and everything comes out all right. If you should apply the same effect on a bitmap, you are actually increasing each source pixel to cover four pixels (two rows of two horizontal pixels).
Of course, by applying interpolation and filtering, the computer can "smooth" out the edges of the target pixels so they seem to blend into each other and give the appearance of a reasonably resized image but this output is never the same as resizing a vector image; vector images resize perfectly.
You also mentioned DPI in your question. DPI is essentially the number of pixels that correspond to an inch when the image is printed not when it is viewed on a screen. Therefore by increasing the DPI of the image, you do not increase the size of the image on the screen. You only increase the quality of print [which needless to say depends on the maximum resolution of the printer].
If you really desire to resize the image and the image is a bitmap, as a rule of thumb, do not increase the size beyond 200% of the original image's size else you'll lose the quality.
You can see this answer for code to resize bitmap images.
To see a sample vector image, go to this link.
Note Try zooming in and out of the image to see how well it resizes.
A typical bitmap are the StackOverflow sprites. They do not keep their quality resized.
Further Reading
Vector Graphics: http://en.wikipedia.org/wiki/Vector_image
Bitmap Graphics: http://en.wikipedia.org/wiki/Bitmap_image

Simply If the original image is smaller then the re-sized image then there is hardly anything you can do. Rest is a research problem.

This would only be possible if it's a vector graphic. Look into SVG. Otherwise, I think you might need Silverlight or Flex for that part.

What you're asking isn't really possible. You can't enlarge an image while maintaining the same quality.
If you think about an image as a mapped array of pixels (literally, a "bit-map"), this makes sense. The image is saved with a fixed amount of data, and that's all you have to work with when you resize it. Any examples to the contrary (like TV shows, as suggested by one of the comments) are purely fictional.
The best that you can do is set the InterpolationMode property of the Graphics object you're using to do the resizing to "HighQualityBicubic", which is the highest quality smoothing algorithm supported by GDI+ and in fact by every major graphics package on the market. It's the best that even Adobe Photoshop has to offer. Essentially, interpolation means that the computer is calculating the approximate value of the new pixels you're adding to make the image larger from the relative values of neighboring pixels. It's a "best guess" method, but it's the best compromise we've come up with yet.
At the very least, the resulting images won't have "jaggies" or rough, pixelated lines.
Sample code:
Graphics g;
g.InterpolationMode = Drawing.Drawing2D.InterpolationMode.HighQualityBicubic;
// ... insert the rest of your code here
Beyond that, it's worth noting that GDI+ (which the .NET Framework uses internally for graphics routines) works best with image sizes that are multiples of 16. So if it all possible, you should try and make the width and height of your resized images a multiple of 16. This will preserve as much of the original image quality as possible.
The ideal solution is to switch to vector graphics that can be resized at will. Instead of pixel information, they contain mathematical information used to draw or "render" the image. Read more on Wikipedia.

let's try metadata in GDI+, may be it can suit your request