在 C# 中使用纵横比调整图像大小并裁剪中心图像，因此没有间隙
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Resize image in C# with aspect ratio and crop central image so there are no gaps
提问by Indy
I'm trying to resize user uploaded images to a landscape dimensions e.g. 450w and 250h while maintaining aspect ratio, but to avoid resized images like portrait images having gaps on the side I would like to crop the centre of the image to fill the resized dimensions.
我正在尝试将用户上传的图像调整为横向尺寸，例如 450w 和 250h，同时保持纵横比，但为了避免调整大小的图像，例如侧面有间隙的纵向图像，我想裁剪图像的中心以填充调整后的尺寸.
I have found plenty of code to resize images while maintaining aspect ratio but not what I am looking for above, I'm hoping someone can help.
我找到了很多代码来调整图像大小，同时保持纵横比，但不是我在上面寻找的，我希望有人能提供帮助。
采纳答案by st78
You should pass needToFill = true:
你应该通过needToFill = true：
public static System.Drawing.Image FixedSize(Image image, int Width, int Height, bool needToFill)
{
#region calculations
int sourceWidth = image.Width;
int sourceHeight = image.Height;
int sourceX = 0;
int sourceY = 0;
double destX = 0;
double destY = 0;
double nScale = 0;
double nScaleW = 0;
double nScaleH = 0;
nScaleW = ((double)Width / (double)sourceWidth);
nScaleH = ((double)Height / (double)sourceHeight);
if (!needToFill)
{
nScale = Math.Min(nScaleH, nScaleW);
}
else
{
nScale = Math.Max(nScaleH, nScaleW);
destY = (Height - sourceHeight * nScale) / 2;
destX = (Width - sourceWidth * nScale) / 2;
}
if (nScale > 1)
nScale = 1;
int destWidth = (int)Math.Round(sourceWidth * nScale);
int destHeight = (int)Math.Round(sourceHeight * nScale);
#endregion
System.Drawing.Bitmap bmPhoto = null;
try
{
bmPhoto = new System.Drawing.Bitmap(destWidth + (int)Math.Round(2 * destX), destHeight + (int)Math.Round(2 * destY));
}
catch (Exception ex)
{
throw new ApplicationException(string.Format("destWidth:{0}, destX:{1}, destHeight:{2}, desxtY:{3}, Width:{4}, Height:{5}",
destWidth, destX, destHeight, destY, Width, Height), ex);
}
using (System.Drawing.Graphics grPhoto = System.Drawing.Graphics.FromImage(bmPhoto))
{
grPhoto.InterpolationMode = InterpolationMode.HighQualityBicubic;
grPhoto.CompositingQuality = CompositingQuality.HighQuality;
grPhoto.SmoothingMode = SmoothingMode.HighQuality;
Rectangle to = new System.Drawing.Rectangle((int)Math.Round(destX), (int)Math.Round(destY), destWidth, destHeight);
Rectangle from = new System.Drawing.Rectangle(sourceX, sourceY, sourceWidth, sourceHeight);
//Console.WriteLine("From: " + from.ToString());
//Console.WriteLine("To: " + to.ToString());
grPhoto.DrawImage(image, to, from, System.Drawing.GraphicsUnit.Pixel);
return bmPhoto;
}
}
