A PictureBox which has SizeMode.Zoom and enlarges the source image adds white at the bottom and right edges. Anyone have a simple proven workaround? I beleive the bug is in GDI+ so the obvious custom repaint will not fix it. Currently I'm using WPF which I want to avoid.
I'll even settle for a kluge that replaces the bad white with black :)
Example: from a source having single central white pixel, instead of this:
it gives this:
The code is:
private void PictureBoxZoomBug()
{
BitmapSource bitmapSource =
BitmapSource.Create(3, 3, 96, 96, System.Windows.Media.PixelFormats.Gray8, null,
new byte[] { 0, 0, 0, 0, 0xFF, 0, 0, 0, 0 }, 3);
TestDiscamImage.Source = bitmapSource; // OK
Bitmap bitmap;
using (MemoryStream stream = new MemoryStream())
{
PngBitmapEncoder enc = new PngBitmapEncoder();
enc.Frames.Add(BitmapFrame.Create(bitmapSource));
enc.Save(stream);
bitmap = new System.Drawing.Bitmap(stream);
}
TestDiscamCapture_pictureBox.Image = bitmap; // Extra white at bottom and right
}
Thanks
Related
I'm a little baffled by a memory leak in my WPF code. I'm rendering some 3D geometry to several RenderTargetBitmaps, then rendering each of those to a large, master RenderTargetBitmap. But when I do this, I get a memory leak that crashes my app after just a minute or two.
I've reproduced the error in the following simplified piece of code.
private void timer1_Tick(object sender, EventArgs e) {
// if first time, create final stitch bitmap and set UI image source
if (stitch == null) {
stitch = new RenderTargetBitmap(1280, 480, 96, 96, PixelFormats.Pbgra32);
myImage.Source = stitch;
}
// create visual and render to img1
Rect rect = new Rect(new Point(160, 100), new Size(320, 80));
DrawingVisual dvis = new DrawingVisual();
using (DrawingContext dc = dvis.RenderOpen()) {
dc.DrawRectangle(System.Windows.Media.Brushes.LightBlue, (System.Windows.Media.Pen)null, rect);
}
RenderTargetBitmap img1 = new RenderTargetBitmap(640, 480, 96, 96, PixelFormats.Pbgra32);
img1.Render(dvis);
// create visual and render to final stitch
DrawingVisual vis = new DrawingVisual();
using (DrawingContext dc = vis.RenderOpen()) {
dc.DrawImage(img1, new Rect(0, 0, 640, 480));
}
stitch.Clear();
stitch.Render(vis);
}
Can anyone see anything obvious that is going wrong here? Why would this code have an egregious memory leak?
if you monitor behaviors of the RenderTargetBitmap class using Resource Monitor, you can see each time this class called, you lose 500KB of your memory. my Answer to your Question is: Dont use RenderTargetBitmap class so many times
You cant even release the Used Memory of RenderTargetBitmap.
If you really need using RenderTargetBitmap class, just add these lines at End of your code.
GC.Collect()
GC.WaitForPendingFinalizers()
GC.Collect()
This maybe solve your problem:
private void timer1_Tick(object sender, EventArgs e) {
// if first time, create final stitch bitmap and set UI image source
if (stitch == null) {
stitch = new RenderTargetBitmap(1280, 480, 96, 96, PixelFormats.Pbgra32);
myImage.Source = stitch;
}
// create visual and render to img1
Rect rect = new Rect(new Point(160, 100), new Size(320, 80));
DrawingVisual dvis = new DrawingVisual();
using (DrawingContext dc = dvis.RenderOpen()) {
dc.DrawRectangle(System.Windows.Media.Brushes.LightBlue, (System.Windows.Media.Pen)null, rect);
}
RenderTargetBitmap img1 = new RenderTargetBitmap(640, 480, 96, 96, PixelFormats.Pbgra32);
img1.Render(dvis);
// create visual and render to final stitch
DrawingVisual vis = new DrawingVisual();
using (DrawingContext dc = vis.RenderOpen()) {
dc.DrawImage(img1, new Rect(0, 0, 640, 480));
}
GC.Collect();
GC.WaitForPendingFinalizers();
GC.Collect();
stitch.Clear();
stitch.Render(vis);
}
I'm trying to save a WriteableBitmap to png but always end up with a 24 bit image (no alpha channel).
WriteableBitmap image = new WriteableBitmap(100, 100, 600, 600, PixelFormats.Bgra32, null);
int stride = image.PixelWidth * image.Format.BitsPerPixel / 8;
image.WritePixels(new System.Windows.Int32Rect(0, 0, image.PixelWidth, image.PixelHeight), emptyArray, stride, 0);
FileStream filestream = new FileStream(imageSrc, FileMode.Create);
PngBitmapEncoder encoder = new PngBitmapEncoder();
encoder.Frames.Add(BitmapFrame.Create((image)));
encoder.Save(filestream);
emptyArray is an array with all pixels being (255, 0, 0, 0) so I can test if the saving has worked.
Any ideas?
I managed to find the problem: the file was altered some place else and overwrote the intial image. So the initial saving of the image worked fine. Sorry for the hassle!
I have a DrawingBrush with some vector graphics. I want to convert it to BitmapSource as an intermediate step to getting it to Bitmap. What's the (best) way to do this?
public static BitmapSource BitmapSourceFromBrush(Brush drawingBrush, int size = 32, int dpi = 96)
{
// RenderTargetBitmap = builds a bitmap rendering of a visual
var pixelFormat = PixelFormats.Pbgra32;
RenderTargetBitmap rtb = new RenderTargetBitmap(size, size, dpi, dpi, pixelFormat);
// Drawing visual allows us to compose graphic drawing parts into a visual to render
var drawingVisual = new DrawingVisual();
using (DrawingContext context = drawingVisual.RenderOpen())
{
// Declaring drawing a rectangle using the input brush to fill up the visual
context.DrawRectangle(drawingBrush, null, new Rect(0, 0, size, size));
}
// Actually rendering the bitmap
rtb.Render(drawingVisual);
return rtb;
}
I'm writing a program in WPF application that simulates the game of life.
How can I preform GDI+ like graphics operations to create an Image that contains the grid of cells?
(Normally, in WinForms, I would have know how to do this operation).
Edit:
I used this code:
WriteableBitmap wb = new WriteableBitmap(width * 5, height * 5, 100, 100, new PixelFormat(), new BitmapPalette(new List<Color> { Color.FromArgb(255, 255, 0, 0) }));
wb.WritePixels(new Int32Rect(0, 0, 5, 5), new IntPtr(), 3, 3);
Background.Source = wb;
Background is a System.Windows.Controls.Image Control
You could use a WriteableBitmap or use a WPF container such as a Grid or Canvas with a lot of rectangles in it. A lot depends on the size of the gameboard. A WriteableBitmap might be better suited for a huge map and a canvas or grid might be easier for smaller sizes.
Is this what you are looking for?
I think you're making things harder on yourself by using WriteableBitmap.WritePixel. You'll have a much better time drawing with Shapes or using RendterTargetBitmap and a DeviceContext.
Here's some code on how you would draw using this method.
MainForm's XAML:
<Grid>
<Image Name="Background"
Width="200"
Height="200"
VerticalAlignment="Center"
HorizontalAlignment="Center" />
</Grid>
MainForm's Code-Behind:
private RenderTargetBitmap buffer;
private DrawingVisual drawingVisual = new DrawingVisual();
public MainWindow()
{
InitializeComponent();
}
protected override void OnRender(DrawingContext drawingContext)
{
base.OnRender(drawingContext);
buffer = new RenderTargetBitmap((int)Background.Width, (int)Background.Height, 96, 96, PixelFormats.Pbgra32);
Background.Source = buffer;
DrawStuff();
}
private void DrawStuff()
{
if (buffer == null)
return;
using (DrawingContext drawingContext = drawingVisual.RenderOpen())
{
drawingContext.DrawRectangle(new SolidColorBrush(Colors.Red), null, new Rect(0, 0, 10, 10));
}
buffer.Render(drawingVisual);
}
Adjust the Width/Height of the Image to whatever you desire. All of your drawing logic should be inside of the using statement. You'll find the methods on DrawingContext are much more flexible and easier to understand than WritePixel. Call "DrawStuff" whenever you want to trigger a redraw.
i have an ico file that contains a 48x48 and a 256x256 Vista PNG version (as well as the 32x32 and 16x16 versions). i want to draw the icon using the appropriate internal size version.
i've tried:
Icon ico = Properties.Resources.TestIcon;
e.Graphics.DrawIcon(ico, new Rectangle(0, 0, 48, 48));
e.Graphics.DrawIcon(ico, new Rectangle(48, 0, 256, 256));
But they draw the 32x32 version blown up to 48x48 and 256x256 respectively.
i've tried:
Icon ico = Properties.Resources.TestIcon;
e.Graphics.DrawIconUnstretched(ico, new Rectangle(0, 0, 48, 48));
e.Graphics.DrawIconUnstretched(ico, new Rectangle(48 0, 256, 256));
But those draw the 32x32 version unstretched.
i've tried:
Icon ico = Properties.Resources.TestIcon;
e.Graphics.DrawImage(ico.ToBitmap(), new Rectangle(0, 0, 48, 48));
e.Graphics.DrawImage(ico.ToBitmap(), new Rectangle(48, 0, 256, 256));
But those draw a stretched version of the 32x32 icon.
How do i make the icon draw itself using the appropriate size?
Additionally, i want to draw using the 16x16 version. i've tried:
Icon ico = Properties.Resources.TestIcon;
e.Graphics.DrawIcon(ico, new Rectangle(0, 0, 16, 16));
e.Graphics.DrawIconUnstretched(ico, new Rectangle(24, 0, 16, 16));
e.Graphics.DrawImage(ico.ToBitmap(), new Rectangle(48, 0, 16, 16));
But all those use the 32x32 version scaled down, except for the Unstretched call, which crops it to 16x16.
How do i make the icon draw itself using the appropriate size?
Following schnaader's suggestion of constructing a copy of the icon with the size you need doesn't work for 256x256 size. i.e. the following does not work (it uses a scaled version of the 48x48 icon):
e.Graphics.DrawIcon(
new Icon(ico, new Size(256, 256)),
new Rectangle(0, 0, 256, 256));
While the following two do work:
e.Graphics.DrawIcon(
new Icon(ico, new Size(16, 16)),
new Rectangle(0, 0, 16, 16));
e.Graphics.DrawIcon(
new Icon(ico, new Size(48, 48)),
new Rectangle(0, 0, 48, 48));
Today, I made a very nice function for extracting the 256x256 Bitmaps from Vista icons.
I use it to display the large icon ( 256x256 ) as a Bitmap in "About" box. For example, this code gets Vista icon as PNG image, and displays it in a 256x256 PictureBox:
picboxAppLogo.Image = ExtractVistaIcon(Icon.ExtractAssociatedIcon(myIcon));
This function takes Icon object as a parameter. So, you can use it with any icons - from resources, from files, from streams, and so on. (Read below about extracting EXE icon).
It runs on any OS, because it does not use any Win32 API, it is 100% managed code :-)
// Based on: http://www.codeproject.com/KB/cs/IconExtractor.aspx
// And a hint from: http://www.codeproject.com/KB/cs/IconLib.aspx
Bitmap ExtractVistaIcon(Icon icoIcon)
{
Bitmap bmpPngExtracted = null;
try
{
byte[] srcBuf = null;
using (System.IO.MemoryStream stream = new System.IO.MemoryStream())
{ icoIcon.Save(stream); srcBuf = stream.ToArray(); }
const int SizeICONDIR = 6;
const int SizeICONDIRENTRY = 16;
int iCount = BitConverter.ToInt16(srcBuf, 4);
for (int iIndex=0; iIndex<iCount; iIndex++)
{
int iWidth = srcBuf[SizeICONDIR + SizeICONDIRENTRY * iIndex];
int iHeight = srcBuf[SizeICONDIR + SizeICONDIRENTRY * iIndex + 1];
int iBitCount = BitConverter.ToInt16(srcBuf, SizeICONDIR + SizeICONDIRENTRY * iIndex + 6);
if (iWidth == 0 && iHeight == 0 && iBitCount == 32)
{
int iImageSize = BitConverter.ToInt32(srcBuf, SizeICONDIR + SizeICONDIRENTRY * iIndex + 8);
int iImageOffset = BitConverter.ToInt32(srcBuf, SizeICONDIR + SizeICONDIRENTRY * iIndex + 12);
System.IO.MemoryStream destStream = new System.IO.MemoryStream();
System.IO.BinaryWriter writer = new System.IO.BinaryWriter(destStream);
writer.Write(srcBuf, iImageOffset, iImageSize);
destStream.Seek(0, System.IO.SeekOrigin.Begin);
bmpPngExtracted = new Bitmap(destStream); // This is PNG! :)
break;
}
}
}
catch { return null; }
return bmpPngExtracted;
}
IMPORTANT! If you want to load this icon directly from EXE file, then you CAN'T use Icon.ExtractAssociatedIcon(Application.ExecutablePath) as a parameter, because .NET function ExtractAssociatedIcon() is so stupid, it extracts ONLY 32x32 icon!
Instead, you better use the whole IconExtractor class, created by Tsuda Kageyu (http://www.codeproject.com/KB/cs/IconExtractor.aspx). You can slightly simplify this class, to make it smaller. Use IconExtractor this way:
// Getting FILL icon set from EXE, and extracting 256x256 version for logo...
using (TKageyu.Utils.IconExtractor IconEx = new TKageyu.Utils.IconExtractor(Application.ExecutablePath))
{
Icon icoAppIcon = IconEx.GetIcon(0); // Because standard System.Drawing.Icon.ExtractAssociatedIcon() returns ONLY 32x32.
picboxAppLogo.Image = ExtractVistaIcon(icoAppIcon);
}
Note: I'm still using my ExtractVistaIcon() function here, because I don't like how IconExtractor handles this job - first, it extracts all icon formats by using IconExtractor.SplitIcon(icoAppIcon), and then you have to know the exact 256x256 icon index to get the desired vista-icon. So, using my ExtractVistaIcon() here is much faster and simplier way :)