Resizing picture C#

Question

need help. i want to resize a certain picture but when i run this code it give me the error {"A generic error occurred in GDI+."}

 private void btnPic_Click(object sender, EventArgs e)
        {
            OpenFileDialog open = new OpenFileDialog();
            open.Filter = "Images|*.bmp;*.jpg;*.gif|All files|*.*";

            if (open.ShowDialog(this) == DialogResult.OK)
            {

                 var image = Image.FromFile(open.FileName);
                 var newImage = ScaleImage(image, 300, 400);
                 newImage.Save(@open.FileName, ImageFormat.Png);

            }
}


 public static Image ScaleImage(Image image, int maxWidth, int maxHeight)
        {
            var ratioX = (double)maxWidth / image.Width;
            var ratioY = (double)maxHeight / image.Height;
            var ratio = Math.Min(ratioX, ratioY);

            var newWidth = (int)(image.Width * ratio);
            var newHeight = (int)(image.Height * ratio);

            var newImage = new Bitmap(newWidth, newHeight);
            Graphics.FromImage(newImage).DrawImage(image, 0, 0, newWidth, newHeight);
            return newImage;
        }

Answer 1

While you're saving, your stream is still open for the open.FileName and you can't save the other file with that same name. You should either do image.Dispose() to release the handle so the Save can overwrite or you should change the filename.

private void button1_Click(object sender, EventArgs e)
        {
            OpenFileDialog open = new OpenFileDialog();
            open.Filter = "Images|*.bmp;*.jpg;*.gif|All files|*.*";

            if (open.ShowDialog(this) == DialogResult.OK)
            {

                var image = Image.FromFile(open.FileName);
                var newImage = ScaleImage(image, 300, 400);
                image.Dispose();//Add this to your code
                newImage.Save(open.FileName, ImageFormat.Png);
            }

Or change the filename

private void button1_Click(object sender, EventArgs e)
        {
            OpenFileDialog open = new OpenFileDialog();
            open.Filter = "Images|*.bmp;*.jpg;*.gif|All files|*.*";

            if (open.ShowDialog(this) == DialogResult.OK)
            {

                var image = Image.FromFile(open.FileName);
                var newImage = ScaleImage(image, 300, 400);
                string path = "1.png";
                newImage.Save(open.FileName, ImageFormat.Png);
            } 

Answer 2

You could try using this version instead.

private void btnPic_Click(object sender, EventArgs e)
{
    OpenFileDialog open = new OpenFileDialog();
    open.Filter = "Images|*.bmp;*.jpg;*.gif|All files|*.*";

    if (open.ShowDialog(this) == DialogResult.OK)
    {

         var image = Image.FromFile(open.FileName);
         var newImage = ResizeCenterCropped(image, 300, 400);
         newImage.Save(@open.FileName, ImageFormat.Png);

    }
}   

public static Image ResizeCenterCropped(Image image, int width, int height)
{
    var rect = CreateCroppedRectangle(image, width, height);
    rect.X = (image.Width / 2) - (rect.Width / 2);
    rect.Y = (image.Height / 2) - (rect.Height / 2);
    return Resize(image, new Rectangle(0, 0, width, height), rect);
}

public static Image Resize(Image image, Rectangle destRectange, Rectangle sourceRectangle)
{
    var rezisedImage = new Bitmap(destRectange.Width, destRectange.Height)
    using (var g = Graphics.FromImage(rezisedImage))
    {
        g.SmoothingMode = SmoothingMode.AntiAlias;
        g.InterpolationMode = InterpolationMode.HighQualityBicubic;
        g.PixelOffsetMode = PixelOffsetMode.HighQuality;
        g.DrawImage(image, destRectange, sourceRectangle, GraphicsUnit.Pixel);
        return rezisedImage;
    }
}

public static Rectangle CreateCroppedRectangle(Image image, int width, int height)
{
    var size = new Size(width, height);
    var size2 = new Size(image.Width, image.Height);

    //The maximum scale width we could use
    float maxWidthScale = (float)size2.Width / (float)size.Width;

    //The maximum scale height we could use
    float maxHeightScale = (float)size2.Height / (float)size.Height;

    //Use the smaller of the 2 scales for the scaling
    float scale = Math.Min(maxHeightScale, maxWidthScale);


    size.Width = (int)(size.Width * scale);
    size.Height = (int)(size.Height * scale);

    return new Rectangle(new Point(), size);
}