We Keep Coding

Saved png image lose transparency when inserted in Catia V5 CATDrawing

I have a problem with transparency in the .png image when inserting to Catia V5 CATDrawing document. Something changes in the image after saving with System.Drawing.Image.Save(). If a newly saved image is opened with Paint.NET image is transparent and everything seems fine, but when inserted in CATDrawing image has no transparency. I can't find out what is changed in the image to cause this loss of transparency.
I'm rotating image that's why I need to save it. This is the code I'm using to rotate and save images.
Bitmap image1 = (Bitmap)Image.FromFile(sImagePath1, true);
image1.RotateFlip(RotateFlipType.Rotate90FlipNone);
image1.MakeTransparent();
image1.Save(sImagePath2, ImageFormat.Png);
I have also tried and failed with NuGet package Magick.NET-Q16-AnyCPU
using (MagickImage mimg = new(sImagePath1))
{
mimg.Rotate(90);
mimg.Write(sImagePath2);
}
and with save as stream
Bitmap image1 = (Bitmap)Image.FromFile(sImagePath1, true);
image1.RotateFlip(RotateFlipType.Rotate90FlipNone);
using (FileStream outputFileStream = new(sImagePath2, FileMode.Create))
{
var stream = new MemoryStream();
image1.Save(stream, ImageFormat.Png);
stream.Position = 0;
stream.CopyTo(outputFileStream);
}
Question: is there any other solution to rotate and save images via C# code?

Hi I'm afraid that Catia V5 can't import png with transparency. Try it yourself if manually putting the image into drawing keeps transparency. I Tried it but in my case it doesn't work.
In Catia you can rotate the picture manually but not trough api.
You can try vector image instead of bitmap, but this is just my guess.

How to draw vector graphics and save it in PDF file?

I'm working on a project which generally is collecting data and drawing results in charts. (Using C#) I need to save my charts in a PDF file. My question is, how to save charts in a PDF file without loosing resolution? My point is how to draw vector graphics instead of raster graphics?
I tried iTextSharp to create PDF file but the result is not satisfying at all!
I'm new here, so I'm not able to upload pictures.
Here is the result after saving my file:
https://www.dropbox.com/s/ruwtc82hfosxk6y/Test.pdf?dl=0
Here is the PDF that I need to create:
https://www.dropbox.com/s/jvu5uu069imo9xc/nir%20well%20abfar.pdf?dl=0

There are two ways I know of to get high-quality images from your Chart into a PDF.
One is by using vector formats:
Use chart.SaveImage with one of the three emf formats.
Convert the resulting emf file to wmf
Insert the wmf file into your iTextSharp document.
1 and 3 are one-liners. But step 2 is not. In fact I haven't found a working c# solution at all. The best was a weird reference to an edit that has disappeared here ..
If you can use some other program to do the conversion you will get nice results like this demo pdf file.. I used Illustrator for the conversion.
Two: If you can't get step 2 to work, you can still get nice results, if you use raster images with a nice and high resolution. Here is how to do it:
First we hide the Chart, so we don't scare the user. Then we make it as large as we want the output to be. Then we DrawToBitmap and finally we reset the chart again..:
Size s = chart1.Size;
chart1.Hide();
// pick your size in pixels
// I simply multiply my screen size..:
chart1.Size = new System.Drawing.Size(s.Width * 5, s.Height * 5);
using (Bitmap bmp = new Bitmap(chart1.ClientSize.Width, chart1.ClientSize.Height))
{
// you should set the resolution,
// although I didn't find a way for iTextSharp to use it visually
bmp.SetResolution(600, 600);
using (Graphics G = Graphics.FromImage(bmp))
{
G.SmoothingMode = SmoothingMode.HighQuality;
G.TextRenderingHint = System.Drawing.Text.TextRenderingHint.AntiAlias;
chart1.DrawToBitmap(bmp, chart1.ClientRectangle);
bmp.Save(yourImageFile, ImageFormat.Png);
}
}
chart1.Size = s;
chart1.Show();
You could also use SaveImage and save a few lines, but you can't set the resolution of the png file there and it will be saved at the currnt screen resolution, which is 96dpi here..
Now you have a large image and will probably have to scale it down in iTextSharp:
iTextSharp.text.Image img = iTextSharp.text.Image.GetInstance(yourImageFile);
img .ScalePercent(15); // scale to fit your needs..
doc.Add(img );
Note that the legend and the labels get very small this way, so you may have to enlarge them before saving. I also found that, when scaling down, the image is rather bright until you zoom in..
Here are two screenshots, one from the chart, the other from the pdf documnet after zooming in a lot (300%)..:

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

Capturing images with blended images in nokia imaging sdk

I am making windows phone app using nokia imaging sdk and example of app is this real time blend demo
I am trying to capture image with Image overlayed image i.e image with other image in top of it as in above example in live camera stream below is code i am trying to capture image with effect
CameraCaptureSequence cameraCaptureSequence = App.Camera.CreateCaptureSequence(1);
MemoryStream stream = new MemoryStream();
cameraCaptureSequence.Frames[0].CaptureStream = stream.AsOutputStream();
await App.Camera.PrepareCaptureSequenceAsync(cameraCaptureSequence);
await cameraCaptureSequence.StartCaptureAsync();
stream.Seek(0, SeekOrigin.Begin);
MediaLibrary library = new MediaLibrary();
library.SavePictureToCameraRoll("picture1.jpg", stream);
but the above code only saves image without effect, so how to capture images with live blended effects from camera.

Basically what you have to do is attach the same effects/filters that you had in the preview to a new image source taking the captured photo stream instead. And probably use a different renderer too.
Either that or set up a duplicate set of filters for the capture. There are reasons to, you could e.g. configure lower quality effects in the preview to help performance.

How to make my image transparent?

I know how to make an image control transparent in C#, but is there a way to make the image (the .jpeg file, not the image control) transparent?
Or, is there a way, when I make the image control transparent, to create new image, save it in some path and give it the other image control's content?

The JPEG file cannot be transparent. However, if you save it as a PNG image it will have a transparency channel.
GIFS also support transparency, but only either completely opaque or completely transparent. Nothing in between.
PNG is your best bet here IMO.

You can set the Image-Controls's Opacity-Property to view it with transparence.
But to get an image-file with transparency, you'll have to render it into a new file.
Here's an example how you can do it.
Image image = new Image(); //or however you get this
image.Opacity = 0.5;
RenderTargetBitmap bmp = new RenderTargetBitmap(image.Source.Width, image.Source.Height, 96, 96, PixelFormats.Pbgra32);
bmp.Render(image);
PngBitmapEncoder png = new PngBitmapEncoder();
png.Frames.Add(BitmapFrame.Create(bmp));
using (Stream fs= File.Create("test.png"))
{
png.Save(fs);
}

There is property transparencycolor. That is what you need if you want to display image on control.