Whats going on is i need to draw a black rectangle over the image. I have to load a tif and then show a blackbox over it. I was helped with some code but i continously got the error: A Graphics object cannot be created from an image that has an indexed pixel format.
So i had to read it in to bit format, but when i display the box it resizes the box wierd. And completly displays the the picture box in all black nothing of the original image. if someone could help me where i'm going wrong that would be awesome.
Bitmap original = (Bitmap)System.Drawing.Image.FromFile(coveted, true);
Bitmap newImage = new Bitmap(original.Width, original.Height);
pictureBox1.Image = newImage;
using (Graphics g = Graphics.FromImage(pictureBox1.Image))
{
using (SolidBrush brush = new SolidBrush(Color.Black))
{
g.FillRectangle(brush, new Rectangle(x1value, y1value, x3value, y3value));
}
}
I'm not sure how I can make this clearer. Whats happening is I have a tif in a unsupported format. So I have to change it to a Bitmap so I can actually draw a rectangle on it. Then I need to display this redacted image (the original with the redaction) in a picturebox. Whats going on with the code above, is once it's completed, all it displays is a blackbox with no original image.
I believe i ran something about using a Bitmap from stream and then closing the stream. Anybody familiar with this?
Thanks to all the help from STO members!! heres the correct code for redacting images if you encounter the error "A Graphics object cannot be created from an image that has an indexed pixel format.".
if you're given the redacted starting points (obviously you have to make the Regex work to your situation):
//Regex for pulling points from a file
string x1 = x1 = Regex.Match(l, #"\r\n(\d+)\r\n(\d+)").Groups[2].Value;
string y1 = y1 = Regex.Match(l, #"\r\n(\d+)\r\n(\d+)\r\n(\d+)").Groups[3].Value;
string x2 = x2 = Regex.Match(l, #"\r\n(\d+)\r\n(\d+)\r\n(\d+)\r\n(\d+)").Groups[4].Value;
string y2 = y2 = Regex.Match(l, #"\r\n(\d+)\r\n(\d+)\r\n(\d+)\r\n(\d+)\r\n(\d+)").Groups[5].Value;
string x3 = x3 = Regex.Match(l, #"\r\n(\d+)\r\n(\d+)\r\n(\d+)\r\n(\d+)\r\n(\d+)\r\n(\d+)").Groups[6].Value;
string y3 = y3 = Regex.Match(l, #"\r\n(\d+)\r\n(\d+)\r\n(\d+)\r\n(\d+)\r\n(\d+)\r\n(\d+)\r\n(\d+)").Groups[7].Value;
{
//convert string to int for redacted points
int x1value = Convert.ToInt32(x1);
int y1value = Convert.ToInt32(y1);
int x3value = Convert.ToInt32(x3);
int y3value = Convert.ToInt32(y3);
{
//BEGIN Workaround for indexed pixels
Bitmap original = (Bitmap)System.Drawing.Image.FromFile(YOURFILE, true);
Bitmap newImage = new Bitmap(original);
pictureBox1.Image = newImage; //END Workaround for indexed pixels
using (Graphics g = Graphics.FromImage(pictureBox1.Image)) //start redaction
{
using (SolidBrush brush = new SolidBrush(Color.Black))
{
g.DrawImageUnscaled(newImage, 0,0);
g.FillRectangle(brush, new Rectangle(x1value, y1value, x3value, y3value));
}
} //End Redaction
pictureBox1.SizeMode = PictureBoxSizeMode.StretchImage; //Resized to fit into a static picturebox
}
}
Instead of
Bitmap newImage = new Bitmap(original.Width, original.Height);
you want
Bitmap newImage = new Bitmap(original);
This will make your newImage start with the contents of original.
The difference will be that you will end up with newImage.PixelFormat == PixelFormat.Format32bppArgb, while I'm assuming original.PixelFormat == PixelFormat.Format1bppIndexed.
With PixelFormat.Format32bppArgb, you can create a Graphics object; you cannot with PixelFormat.Format1bppIndexed.
This should work for you:
original = (Bitmap)System.Drawing.Image.FromFile(coveted, true);
using (Graphics g = Graphics.FromImage(original))
{
using (SolidBrush brush = new SolidBrush(Color.Black))
{
g.FillRectangle(brush, new Rectangle(x1value, y1value, x3value, y3value));
}
}
pictureBox1.Image = original;
You aren't drawing the original image on the newImage.
To do so :
g.DrawImageUnscaled(original, 0, 0);
Also, I would do it as follows, I think it works better drawing in RAM, and then showing it to screen. Perhaps I'm wrong though.
using (Graphics g = Graphics.FromImage(newImage))
{
g.DrawImageUnscaled(original, 0, 0);
using (SolidBrush brush = new SolidBrush(Color.Black))
{
g.FillRectangle(brush, new Rectangle(x1value, y1value, x3value, y3value));
}
}
pictureBox1.Image = newImage;
I haven't tested the code above.. good luck though.
Related
Trying to add a watermark image to a png image, i´ve been able to do it, but i want to take out the hardCoded size regulation for the rectangle of the waterMark, and make it always stay in the center of the image. How can i achieve this.
public Form1()
{
InitializeComponent();
picBox.Parent = this;
picBox.Dock = DockStyle.Fill;
picBox.SizeMode = PictureBoxSizeMode.Zoom;
Bitmap Jpg = new Bitmap(#"C:\Users\tferreira\Desktop\213123.PNG");
using (Bitmap Bmp = new Bitmap(#"C:\Users\tferreira\Desktop\logo.png"))
{
using (Bitmap WatermarkBmp = new Bitmap(Bmp, Bmp.Width / 1, Bmp.Height / 1))
{
picBox.Image = WatermarkImage(Jpg, WatermarkBmp, new Point(400, 100), 0.40F);
}
}
}
public Bitmap WatermarkImage(Bitmap ImageToWatermark, Bitmap Watermark, Point WatermarkPosition, float Opacity)
{
using (Graphics G = Graphics.FromImage(ImageToWatermark))
{
using (ImageAttributes IA = new ImageAttributes())
{
ColorMatrix CM = new ColorMatrix();
CM.Matrix33 = Opacity;
IA.SetColorMatrix(CM);
G.DrawImage(Watermark, new Rectangle(WatermarkPosition, Watermark.Size), 0, 0, Watermark.Width, Watermark.Height, GraphicsUnit.Pixel, IA);
}
}
return ImageToWatermark;
}
Right now the images are hardCoded but that will be taken out. If anyone can help me make this watermark allways stay centered i thank you.
I fixed this problem with this nice peace of code.
System.Drawing.Image img = System.Drawing.Image.FromFile(JpgFilePath);
Bitmap jpg = new Bitmap(img);
filePath = JpgFilePath;
int Width = jpg.Width;
int Height = jpg.Height;
jpg.SetResolution(300, 300);
WaterMarked = WatermarkImage(jpg, WaterMarkBit, new Point((Width - WaterMarkBit.Width) / 2, (Height - WaterMarkBit.Height) / 2), 0.4F);
WaterMarked.Save(filePath.Replace(".jpg", "") + ".tif", ImageFormat.Tiff);
filesJpgForTif.Add(JpgFilePath.Replace("jpg", "tif"));
Using the the sizes of the image and sizes of the watermark and divide it by 2 it makes the image always stay centered.
I had an error come up:
A Graphics Object cannot be Created from an Image that has an Indexed Pixel Format
So I implemented this code into my method: Solution for "A Graphics Object cannot be Created from an Image that has an Indexed Pixel Format"
But now my watermark doesnt want to draw on my image.
Please can anyone assist.
Code:
private Image AddWaterMark(Image original)
{
Image waterMark = Image.FromFile(ConfigurationManager.AppSettings["GalleryFolder"] + #"\watermark.png");
Bitmap bm = (Bitmap)original;
Size waterMarkResize = ResizeFit(new Size(original.Width, original.Height));
using (Image watermarkImage = new Bitmap(waterMark, waterMarkResize))
using (Graphics imageGraphics = Graphics.FromImage(new Bitmap(bm.Width, bm.Height)))
{
imageGraphics.DrawImage(bm, new Rectangle(0, 0, bm.Width, bm.Height), 0, 0, bm.Width, bm.Height, GraphicsUnit.Pixel);
using (TextureBrush watermarkBrush = new TextureBrush(watermarkImage))
{
int x = (original.Width / 2 - watermarkImage.Width / 2);
int y = (original.Height / 2 - watermarkImage.Height / 2);
watermarkBrush.TranslateTransform(x, y);
imageGraphics.FillRectangle(watermarkBrush, new Rectangle(new Point(x, y), new Size(watermarkImage.Width + 1, watermarkImage.Height)));
}
}
return bm;
}
You're creating a new Bitmap to pass to Graphics.FromImage then returning the uneditted original Bitmap. Create the new Bitmap independently, pass it to FromImage then return the new Bitmap.
var edit = new Bitmap(bm.Width, bm.Height);
// ...
using (Graphics imagesGraphics = Graphics.FromImage(edit))
{
// draw original
// draw watermark
}
return edit;
I want to crop a rotated Rectangle from an image. What I want to do is something like that :
System.Windows.Shapes.Rectangle rect = new System.Windows.Shapes.Rectangle();
// rect.RadiusX = ...; // rect.Height = ....; ..
rect.RenderTransform = new RotateTransform(angle);
and then crop this rectangle from Image.
All codes that I have found cropped a System.Windows.Drawing rectangle from the image.But, I need to crop a System.Windows.Shapes to apply the rotate Transform which is not applicable with System.Windows.Drawing Rectangle.
Since your question lacked some code. So as far as I have understood, the given method would provide you with appropriate results. If the answer is not upto your mark, then please elaborate the question statement more.
public static Bitmap CropRotatedRect(Bitmap source, Rectangle rect, float angle, bool HighQuality)
{
Bitmap result = new Bitmap(rect.Width, rect.Height);
using (Graphics g = Graphics.FromImage(result))
{
g.InterpolationMode = HighQuality ? InterpolationMode.HighQualityBicubic : InterpolationMode.Default;
using (Matrix mat = new Matrix())
{
mat.Translate(-rect.Location.X, -rect.Location.Y);
mat.RotateAt(angle, rect.Location);
g.Transform = mat;
g.DrawImage(source, new Point(0, 0));
}
}
return result;
}
Hope that helps.
The thing I want to do is simple. I want to take a picture I already have and paste it into a blank graphics/picture at a certain point, thus expanding my picture's bounds.
To clarify :
private static Image PasteImage(Image startimage) //start image is a square of Size(30,30)
{
//Create a new picture/graphics with size of (900,900);
//Paste startimage inside the created picture/graphics at Point (400,450)
//Return the picture/graphics which should return a square within a square
}
private static Image PasteImage(Image startimage)
{
int width = Math.Max(900, 400 + startimage.Width);
int height = Math.Max(900, 450 + startimage.Height);
var bmp = new Bitmap(width, height);
using (Graphics g = Graphics.FromImage(bmp)) {
g.DrawImage(startimage, 400, 450);
}
return bmp;
}
It's better to get rid of constants in your code and add a couple of additional params:
private static Image PasteImage(Image startimage, Size size, Point startpoint)
{
int width = Math.Max(size.Width, startpoint.X + startimage.Width);
int height = Math.Max(size.Height, startpoint.Y + startimage.Height);
var bmp = new Bitmap(width, height);
using (Graphics g = Graphics.FromImage(bmp)) {
g.Clear(Color.Black);
g.DrawImage(startimage, new Rectangle(startpoint, startimage.Size));
}
return bmp;
}
Create an image from the startimage using the following
Graphics.FromImage(startimage);
Draw the image where you want to using
g.DrawImage(...)
here is the code i'm using, i really need to make it so the text does not appear inside of a box. is that possible?
int width = (int)g.MeasureString(line, f).Width;
int height = (int)g.MeasureString(line,f).Height;
b = new Bitmap(b, new Size(width, height));
g = Graphics.FromImage(b);
g.Clear(Color.Empty);
g.DrawString(line,f, new SolidBrush(Color.Black), 0, 0);
b.Save(savepoint+line+".tif", System.Drawing.Imaging.ImageFormat.Tiff);
g.Flush();
What i mean is there can be no Rectangle around the text that is converted to image. So I need to watch it to the same color to create the illusion there is no box, or to never write out that rectangle period.
Use the color Transparent for the backgtround and a file format that supports transparency, like PNG:
var measure = g.MeasureString(line, f);
int width = (int)measure.Width;
int height = (int)measure.Height;
using (Bitmap b = new Bitmap(width, height)) {
using (Graphics bg = Graphics.FromImage(b)) {
bg.Clear(Color.Transparent);
using (Brush black = new SolidBrush(Color.Black)) {
bg.DrawString(line, f, black, 0, 0);
}
}
b.Save(savepoint+line+".png", System.Drawing.Imaging.ImageFormat.Png);
}
I notice that you did overwrite your Graphics instance, didn't dispose the objects that you create, and called Graphics.Flush for no apparent reason...