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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.

Metro App stretch="fill" results in poor quality

In WPF I could do RenderOptions.BitmapScalingMode, but this isn't available in Metro apps. Is there a way I can get better quality scaling when I scale an image down?

You shouldn't use Fill for Stretch property if you want your image to keep its initial ratio.
Use Uniform, or UniformToFill.
More info here :
http://msdn.microsoft.com/en-us/library/windows/apps/windows.ui.xaml.controls.image.aspx
http://msdn.microsoft.com/en-us/library/windows/apps/windows.ui.xaml.controls.image.stretch.aspx
http://msdn.microsoft.com/en-us/library/windows/apps/windows.ui.xaml.media.stretch.aspx
Next, on the subject of scaling down an Image, there already is an answer here : High quality image scaling.
Basically, use DecodePixelHeight or DecodePixelWidth, or better, use a different source image.
http://msdn.microsoft.com/en-us/library/windows/apps/hh465362.aspx
Don’t use larger images that are scaled down Larger images that are scaled down show scaling artifacts and jagged edges on standard tablets. Photographs are the only exception as they can look good when scaled down. You should ensure that your images look great on the 100% scale using the above guidance.

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

reduce image size in bytes without resize and quality lose in c#

I m using C#.NET 4.0
I have an jpeg image and i want to reduce its size in bytes .I don't want to change the image size in manner of height and width and not want to lose image quality.Some bit of reduce quality is not an issue. I try to make it a thumbnail image but it reduce the size according to height and width.
I can't found any solution.
Any type help will be appreciated..

Size reduction is generally accompanied by quality reduction. You cannot have it both ways.

How about saving jpeg at 90% quality (which usually provides good quality of an image) and then comparing size with your original jpeg file.
Something like this:
new jpeg < old jpeg ? new jpeg : old jpeg

If you want reduce the image size then you have to trim the width and height, according to that only the size reduces unless it is not possible.

Listview icons show up blurry (C#)

I'm attempting to display a "LargeIcon" view in a listview control, however the images I specify are blurry. This is what I have so far:
alt text http://img220.imageshack.us/img220/1005/blurryiconsql3.jpg
The .png files are 48x48 and that's what I have it set to display at in the ImageList properties. There's one thing that I've noticed (which is probably the cause) but I don't know how to change it. Inside the "Images Collection Editor" where you choose what images you want for the ImageList control, it looks like it's setting the wrong size for each image.
alt text http://img83.imageshack.us/img83/5218/imagepropertiesmf9.jpg
As you can see the "PhysicalDimension" and the "Size" is set to 16x16 and not abled to be manipulated. Does anyone have any ideas? Many thanks!

Be sure to set ImageList.ImageSize to 48 x 48 too.

When adding a .PNG Icon format size the editor tends to pick the first entry size in that file, so it picks up the 16x16 entry and it's stretching that out. That's why you see the 16x16 in the properties there. As suggested, the support for PNG is poor, I'm often found myself rolling over to another format as well to avoid this.
You can open the file in Paint.Net if you need a free editor or something more fully featured like Photoshop or Fireworks and extract the exact size you want.

I'm not sure if its the problem in this specific case, but Microsoft support for the PNG format is generally poor. Try adding the images in .bmp format and they should display fine.

Check also the ColorDepth setting on your ImageList. I had a similar issue with a TreeView control, but after reading the previous posting regarding the size I found this setting, played around with it a bit and found that it greatly affects the way images from an ImageList are rendered. The higher the depth the better the quality.

Be sure to set the ImageList size to 48x48 px BEFORE you add the images.
If the ImageList is set to 32x32 and you add a 48x48 image, the icon is resized to 32x32. When you change the ImageList to 48x48 afterwards, the image is just resized again, thus losing quality and going blurry.
Also, Paint.NET (or Photoshop) can't open .ico files.
Visual Studio/.NET can handle 32-bit PNG images fine, the built-in image editor in VS is a bit lack-lustre though.