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Graphics is blank when trying to turn anti-aliasing off for a bitmap (C#)

What I'm trying to do:
Since in my bitmaps there are some unwanted white edges around the picture that result from anti-aliasing as pointed out from another user from stackoverflow.
I'm trying to convert an image that's inputted into a bitmap, convert bitmap into a Graphics object so that I can set the Smooth Mode to none, and then finally convert that Graphics object to a bitmap so that it can be copied by the user after setting it to the clipboard. I'm not sure if this is a good way of getting rid anti-aliasing in bitmaps but I'm definitely interested in improvements and suggestions.
The issue I'm facing:
The result of the image after is completely blank and does not contain any of the pixels that are previously found in the original bitmap. Here's the result:
This issue applies to all pictures no matter what their format is.
My code:
public PicGen(PictureBox pictureBox)
{
Clipboard.Clear();
Bitmap firstImage = new(pictureBox.Image, pictureBox.Width, pictureBox.Height);
RectangleF cloneRect = new RectangleF(0, 0, firstImage.Width, firstImage.Height);
System.Drawing.Imaging.PixelFormat format = firstImage.PixelFormat;
Bitmap cloneBitmap = firstImage.Clone(cloneRect, format);
Graphics AntiARemover = Graphics.FromImage(cloneBitmap);
AntiARemover.SmoothingMode = System.Drawing.Drawing2D.SmoothingMode.None;
Bitmap finalImg = new(52, 52, AntiARemover);
Clipboard.SetImage(finalImg);
Color backColorBottom = firstImage.GetPixel(0, 0);
firstImage.ReplaceColor(backColorBottom, Color.FromArgb(54, 57, 63));

Bitmap finalImg = new(52, 52, AntiARemover);
From the documentation for this bitmap constructor:
The new Bitmap that this method creates takes its horizontal and vertical resolution from the DpiX and DpiY properties of g, respectively.
If you want create a new image with the content from another you need to call one of the DrawImage methods. You should also dispose your graphics object, and any temporary bitmaps you may use.
using var finalImg = new Bitmap(52,52);
using var graphics = Graphics.FromImage(finalImg);
graphics.SmoothingMode = System.Drawing.Drawing2D.SmoothingMode.None;
graphics.DrawImage(cloneBitmap)
However, edge artifacts typically occur when combining two images using an alpha channel, see Premultiplied alpha. In your example I can only see one input image, so I'm really not sure what it is you are actually trying to do. If you need to convert to premultiplied alpha you can use the following code to convert the color for each pixel
premultiplied.R = (byte)(straight.R * straight.A / 255);
premultiplied.G = (byte)(straight.G * straight.A / 255);
premultiplied.B = (byte)(straight.B * straight.A / 255);
premultiplied.A = straight.A;

Image is not drawn at the correct spot

Bitmap image = ReadBitmap("image.png");
Bitmap imageCopy = new Bitmap(image);
Bitmap canvas = new Bitmap(imageCopy.Width+100, imageCopy.Height);
// From this bitmap, the graphics can be obtained, because it has the right PixelFormat
using(Graphics g = Graphics.FromImage(canvas))
{
// Draw the original bitmap onto the graphics of the new bitmap
g.DrawImage(image, 0, 0);
}
// Use tempBitmap as you would have used originalBmp
InputPictureBox.Image = image;
OutputPictureBox.Image = canvas;
I haven't understood the output of this c# code.
The original image is not placed at the correct position. It should have been at (0, 0).
Also, I need a black background.
So, what is going on and how to correct this?

You are loading an Image, then a copy of this source is created using:
Bitmap bitmap = new Bitmap();
When you create a copy of an Image this way, you sacrifice/alter some details:
Dpi Resolution: if not otherwise specified, the resolution is set to the UI resolution. 96 Dpi, as a standard; it might be different with different screen resolutions and scaling. The System in use also affects this value (Windows 7 and Windows 10 will probably/possibly provide different values)
PixelFormat: If not directly copied from the Image source or explicitly specified, the PixelFormat is set to PixelFormat.Format32bppArgb.
From what you were saying, you probably wanted something like this:
var imageSource = Image.FromStream(new MemoryStream(File.ReadAllBytes(#"[SomeImageOfLena]"))), true, false)
var imageCopy = new Bitmap(imageSource.Width + 100, imageSource.Height, imageSource.PixelFormat))
imageCopy.SetResolution(imageSource.HorizontalResolution, imageSource.VerticalResolution);
using (var g = Graphics.FromImage(imageCopy)) {
g.Clear(Color.Black);
g.CompositingMode = CompositingMode.SourceCopy;
g.InterpolationMode = InterpolationMode.HighQualityBicubic;
g.DrawImage(imageSource, (imageCopy.Width - imageSource.Width) / 2, 0);
pictureBox1.Image?.Dispose();
pictureBox2.Image?.Dispose();
pictureBox1.Image = imageSource;
pictureBox2.Image = imageCopy;
}
This is the result:
(The upper/lower frame black color is actually the Picturebox background color)
When the original Image Dpi Resolution is different from the base Dpi Resolution used when creating an Image copy with new Bitmap(), your results may be different from what is expected.
This is what happens with a source Image of 150, 96 and 72 Dpi in the same scenario:
Another important detail is the IDisposable nature of the Image object.
When you create one, you have to Dispose() of it; explicitly, calling the Dispose method, or implicitly, enclosing the Image contructor in a Using statement.
Also, possibly, don't assign an Image object directly loaded from a FileStream.
GDI+ will lock the file, and you will not be able to copy, move or delete it.
With the file, all resources tied to the Images will also be locked.
Make a copy with new Bitmap() (if you don't care of the above mentioned details), or with Image.Clone(), which will preserve the Image Dpi Resolution and PixelFormat.

I am not completely clear on what you are actually needing to do. But anyway, here is a WPF-friendly example of how to draw an image at a specific position inside another image.
Note if all you want to do is display the image in different size and/or put a black border around it, there are much simpler ways to do simply that, without having to create a second image, such as just laying out the image inside a panel that already has the border style you want.
Notice that I am using classes from the System.Windows.Media namespace because that is what WPF uses. These don't mix easily with the older classes from System.Drawing namespace (some of the class names conflict, and Microsoft's .Net framework lacks built-in methods for converting objects between those types), so normally one needs to simply decide whether to use one or the other sets of drawing tools. I assume you have been trying to use System.Drawing. Each has its own pros and cons that would take too long to explain here.
// using System.Windows.Media;
// using System.Windows.Media.Imaging;
private void DrawTwoImages()
{
// For InputPictureBox
var file = new Uri("C:\\image.png");
var inputImage = new BitmapImage(file);
// If your image is stored in a Resource Dictionary, instead use:
// var inputImage = (BitmapImage) Resources["image.png"];
InputPicture.Source = inputImage;
// imageCopy isn't actually needed for this example.
// But since you had it in yours, here is how it's done, anyway.
var imageCopy = inputImage.Clone();
// Parameters for setting up our output picture
int leftMargin = 50;
int topMargin = 5;
int rightMargin = 50;
int bottomMargin = 5;
int width = inputImage.PixelWidth + leftMargin + rightMargin;
int height = inputImage.PixelHeight + topMargin + bottomMargin;
var backgroundColor = Brushes.Black;
var borderColor = (Pen) null;
// Use a DrawingVisual and DrawingContext for drawing
DrawingVisual dv = new DrawingVisual();
using (DrawingContext dc = dv.RenderOpen())
{
// Draw the black background
dc.DrawRectangle(backgroundColor, borderColor, new Rect(0, 0, width, height));
// Copy input image onto output image at desired position
dc.DrawImage(inputImage, new Rect(leftMargin, topMargin,
inputImage.PixelWidth, inputImage.PixelHeight));
}
// For displaying output image
var rtb = new RenderTargetBitmap( width, height, 96, 96, PixelFormats.Pbgra32 );
rtb.Render(dv);
OutputPicture.Source = rtb;
}

Bold Font is Rendered Wrong

When I try to render a Chinese string like 试标记好不好 Graphics.DrawString draws it
even if I change the Font Linking to SimSun. On the other hand TextRenderer works but it fails to render readable strings when bold fonts are used. It seems there is no correct way to render bold strings.
The issue is described in greater detail here. Am I doing something wrong or does Windows not support professional looking localizable applications with some bold strings in the UI?
The code to repro the issue is for a Windows Forms application with two PictureBoxes:
const string combined = "测试标记好不好This is a aber long";
private void cFontSize_ValueChanged(object sender, EventArgs e)
{
Bitmap bmp = new Bitmap(750, 140);
Font f = new Font("Arial", (float)cFontSize.Value, IsBold ? FontStyle.Bold : FontStyle.Regular);
using (var g = Graphics.FromImage(bmp))
{
g.CompositingMode = System.Drawing.Drawing2D.CompositingMode.SourceOver;
// Rendering with a Background Color solves the issue but
// this would produce boxes of white or black color in the displayed image which looks even worse
TextRenderer.DrawText(g, combined, f, new Point(0, 0), FontColor);
}
cPictureBox.Image = bmp;
Bitmap bmp2 = new Bitmap(750, 140);
using (var g = Graphics.FromImage(bmp2))
{
g.CompositingMode = System.Drawing.Drawing2D.CompositingMode.SourceOver;
g.DrawString(combined, f, FontBrush, 0, 0);
}
cPicture2.Image = bmp2;
}
Update 1:
When I add as Font Link Setting to HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\FontLink\SystemLink
Arial Bold
SIMSUNB.TTC,SimSun Bold
MSGOTHIC.TTC,MS UI Gothic
then Graphics.DrawString looks ok now althogh TextRender now gets problems. After restarting the application now both outputs look font wise ok although TextRenderer still has the problem that bold fonts become unreadable due to anti aliasing with black. I will restart the machine to check out any caching effects.

ASP.NET TextRenderer.DrawText Awful Text Images

Since I've tried to draw string with every combination of smoothing and rendering with Graphics.DrawString() I was thinking that text renderer would do a better job drawing my strings but I think was wrong.
This is how it is supposed to look like:
And this is how it looks like:
Here is my code:
Graphics objGraphics2 = Graphics.FromImage(objBitmap);
objGraphics2.SmoothingMode = System.Drawing.Drawing2D.SmoothingMode.HighQuality;
objGraphics2.TextRenderingHint = System.Drawing.Text.TextRenderingHint.AntiAlias;
objGraphics2.CompositingQuality = System.Drawing.Drawing2D.CompositingQuality.HighQuality;
objGraphics2.InterpolationMode = System.Drawing.Drawing2D.InterpolationMode.HighQualityBilinear;
Font textFont = new Font(textFontFamily, PxtoEm(textSize));
SolidBrush b = new SolidBrush(textColor);
TextRenderer.DrawText(objGraphics2, textValue, textFont, new Rectangle(0, 0, Width, Height), textColor);
Is my PxtoEm method wrong?
public float PxtoEm(int px)
{
float em = (float)(Convert.ToDouble(Convert.ToDouble(px) * Convert.ToDouble(72) / Convert.ToDouble(objBitmap.HorizontalResolution)));
return em;
}
I need some suggestions because this is really awful, it gets worse with larger fonts and images aren't shrunk.
UPDATE: Got it working with bigger fonts(ie. 20px) but with smaller fonts it gets kind of erased on some letters:
This is how it's suposed to be with font Arial 10px:
This is result with Graphics.DrawString()
As you can see it really isn't very good but closest I got. I made some changes to code and got better results with larger font:
This is how it's suposed to be with font Arial 20px:
This is drawing result:
And here is the changed code(I droped em method and used pixels directly, switched to Graphics.DrawString() instead of TextRenderer.DrawText()
Graphics objGraphics = Graphics.FromImage(objBitmap);
objGraphics.SmoothingMode = System.Drawing.Drawing2D.SmoothingMode.HighQuality;
objGraphics.TextRenderingHint = System.Drawing.Text.TextRenderingHint.AntiAliasGridFit;
objGraphics.CompositingQuality = System.Drawing.Drawing2D.CompositingQuality.HighQuality;
objGraphics.InterpolationMode = System.Drawing.Drawing2D.InterpolationMode.HighQualityBicubic;
objGraphics.PixelOffsetMode = System.Drawing.Drawing2D.PixelOffsetMode.HighQuality;
Font textFont = new Font(textFontFamily, textSize,GraphicsUnit.Pixel);
SolidBrush b = new SolidBrush(textColor);
PointF origin = new PointF((float)TextLeft,(float)TextTop);
StringFormat format = StringFormat.GenericTypographic;
objGraphics.DrawString(textValue, textFont, b , origin, format);
If someone has some suggestion to maybe write different method for smaller text sizes and use above code for larger as it works nicely, post it and I'll try it!
UPDATE 3: Finally found solution for everything, and solution was rather simple:
DON'T USE TRANSPARENT BACKGROUND!
And settings are:
objGraphics.SmoothingMode = System.Drawing.Drawing2D.SmoothingMode.HighQuality;
objGraphics.TextRenderingHint = System.Drawing.Text.TextRenderingHint.ClearTypeGridFit; // <-- important!
objGraphics.CompositingQuality = System.Drawing.Drawing2D.CompositingQuality.HighQuality;
objGraphics.InterpolationMode = System.Drawing.Drawing2D.InterpolationMode.HighQualityBicubic;
objGraphics.PixelOffsetMode = System.Drawing.Drawing2D.PixelOffsetMode.HighQuality;
objGraphics.TextContrast = 0;
Here is final image with these settings on white background:
Exactly the same, thanks for suggestions and replies.

I'm not sure it will help but why not create your font without the function call, like this:
Font textFont = new Font(textFontFamily, textSize, GraphicsUnit.Pixel);

I built something to generate image buttons using similar functionality and I had issues with kerneling and the font not stretching to the desired with. The following settings got me really close to what I wanted but still not 100%.
objGraphics2.PixelOffsetMode = System.Drawing.Drawing2D.PixelOffsetMode.HighQuality;
objGraphics2.TextRenderingHint = System.Drawing.Drawing2D.TextRenderingHint.AntiAliasGridFit;

Set Graphics.TextRenderingHint to SingleBitPerPixelGridFit.

I'm not sure if this will solve the issue, but I had a similar problem with drawing text in Direct3D, check out PixelOffsetMode, set it to Half.

How to implement pan/zoom on gigapixel bitmaps?

In my project, I'm using (uncompressed 16-bit grayscale) gigapixel images which come from a high resolution scanner for measurement purposes. Since these bitmaps can not be loaded in memory (mainly due to memory fragmentation) I'm using tiles (and tiled TIFF on disc). (see StackOverflow topic on this)
I need to implement panning/zooming in a way like Google Maps or DeepZoom. I have to apply image processing on the fly before presenting it on screen, so I can not use a precooked library which directly accesses an image file. For zooming I intend to keep a multi-resolution image in my file (pyramid storage). The most useful steps seem to be +200%, 50% and show all.
My code base is currently C# and .NET 3.5. Currently I assume Forms type, unless WPF gives me great advantage in this area. I have got a method which can return any (processed) part of the underlying image.
Specific issues:
hints or references on how to implement this pan/zoom with on-demand generation of image parts
any code which could be used as a basis (preferably commercial or LGPL/BSD like licenses)
can DeepZoom be used for this (i.e. is there a way that I can provide a function to provide a tile at the right resulution for the current zoom level?) ( I need to have pixel accurate addressing still)

This CodeProject article: Generate...DeepZoom Image Collection might be a useful read since it talks about generating a DeepZoom image source.
This MSDN article has a section Dynamic Deep Zoom: Supplying Image Pixels at Run Time and links to this Mandelbrot Explorer which 'kinda' sounds similar to what you're trying to do (ie. he is generating specific parts of the mandelbrot set on-demand; you want to retrieve specific parts of your gigapixel image on-demand).
I think the answer to "can DeepZoom be used for this?" is probably "Yes", however as it is only available in Silverlight you will have to do some tricks with an embedded web browser control if you need a WinForms/WPF client app.
Sorry I can't provide more specific answers - hope those links help.
p.s. I'm not sure if Silverlight supports TIFF images - that might be an issue unless you convert to another format.

I decided to try something myself. I came up with a straightforward GDI+ code, which uses the tiles I've already got. I just filter out the parts which are relevant for current clipping region. It works like magic! Please find my code below.
(Form settings double buffering for the best results)
protected override void OnPaint(PaintEventArgs e)
{
base.OnPaint(e);
Graphics dc = e.Graphics;
dc.ScaleTransform(1.0F, 1.0F);
Size scrollOffset = new Size(AutoScrollPosition);
int start_x = Math.Min(matrix_x_size,
(e.ClipRectangle.Left - scrollOffset.Width) / 256);
int start_y = Math.Min(matrix_y_size,
(e.ClipRectangle.Top - scrollOffset.Height) / 256);
int end_x = Math.Min(matrix_x_size,
(e.ClipRectangle.Right - scrollOffset.Width + 255) / 256);
int end_y = Math.Min(matrix_y_size,
(e.ClipRectangle.Bottom - scrollOffset.Height + 255) / 256);
// start * contain the first and last tile x/y which are on screen
// and which need to be redrawn.
// now iterate trough all tiles which need an update
for (int y = start_y; y < end_y; y++)
for (int x = start_x; x < end_x; x++)
{ // draw bitmap with gdi+ at calculated position.
dc.DrawImage(BmpMatrix[y, x],
new Point(x * 256 + scrollOffset.Width,
y * 256 + scrollOffset.Height));
}
}
To test it, I've created a matrix of 80x80 of 256 tiles (420 MPixel). Of course I'll have to add some deferred loading in real life. I can leave tiles out (empty) if they are not yet loaded. In fact, I've asked my client to stick 8 GByte in his machine so I don't have to bother about performance too much. Once loaded tiles can stay in memory.
public partial class Form1 : Form
{
bool dragging = false;
float Zoom = 1.0F;
Point lastMouse;
PointF viewPortCenter;
private readonly Brush solidYellowBrush = new SolidBrush(Color.Yellow);
private readonly Brush solidBlueBrush = new SolidBrush(Color.LightBlue);
const int matrix_x_size = 80;
const int matrix_y_size = 80;
private Bitmap[,] BmpMatrix = new Bitmap[matrix_x_size, matrix_y_size];
public Form1()
{
InitializeComponent();
Font font = new Font("Times New Roman", 10, FontStyle.Regular);
StringFormat strFormat = new StringFormat();
strFormat.Alignment = StringAlignment.Center;
strFormat.LineAlignment = StringAlignment.Center;
for (int y = 0; y < matrix_y_size; y++)
for (int x = 0; x < matrix_x_size; x++)
{
BmpMatrix[y, x] = new Bitmap(256, 256, PixelFormat.Format24bppRgb);
// BmpMatrix[y, x].Palette.Entries[0] = (x+y)%1==0?Color.Blue:Color.White;
using (Graphics g = Graphics.FromImage(BmpMatrix[y, x]))
{
g.FillRectangle(((x + y) % 2 == 0) ? solidBlueBrush : solidYellowBrush, new Rectangle(new Point(0, 0), new Size(256, 256)));
g.DrawString("hello world\n[" + x.ToString() + "," + y.ToString() + "]", new Font("Tahoma", 8), Brushes.Black,
new RectangleF(0, 0, 256, 256), strFormat);
g.DrawImage(BmpMatrix[y, x], Point.Empty);
}
}
BackColor = Color.White;
Size = new Size(300, 300);
Text = "Scroll Shapes Correct";
AutoScrollMinSize = new Size(256 * matrix_x_size, 256 * matrix_y_size);
}
Turned out this was the easy part. Getting async multithreaded i/o done in the background was a lot harder to acchieve. Still, I've got it working in the way described here. The issues to resolve were more .NET/Form multithreading related than to this topic.
In pseudo code it works like this:
after onPaint (and on Tick)
check if tiles on display need to be retrieved from disc
if so: post them to an async io queue
if not: check if tiles close to display area are already loaded
if not: post them to an async io/queue
check if bitmaps have arrived from io thread
if so: updat them on screen, and force repaint if visible
Result: I now have my own Custom control which uses roughly 50 MByte for very fast access to arbitrary size (tiled) TIFF files.

I guess you can address this issue following the steps below:
Image generation:
segment your image in multiple subimages (tiles) of a small resolution, for instace, 500x500. These images are depth 0
combine a series of tiles with depth 0 (4x4 or 6x6), resize the combination generating a new tile with 500x500 pixels in depth 1.
continue with this approach until get the entire image using only a few tiles.
Image visualization
Start from the highest depth
When user drags the image, load the tiles dynamically
When the user zoom a region of the image, decrease the depth, loading the tiles for that region in a higher resolution.
The final result is similar to Google Maps.