Size, Width和Height都是System.Drawing.Image的Get()属性; 我如何在c#运行时调整图像对象的大小?
现在,我只是创建一个新的图像使用:
// objImage is the original Image
Bitmap objBitmap = new Bitmap(objImage, new Size(227, 171));
Size, Width和Height都是System.Drawing.Image的Get()属性; 我如何在c#运行时调整图像对象的大小?
现在,我只是创建一个新的图像使用:
// objImage is the original Image
Bitmap objBitmap = new Bitmap(objImage, new Size(227, 171));
当前回答
使用下面的函数和下面的例子来改变图像大小:
//Example :
System.Net.Mime.MediaTypeNames.Image newImage = System.Net.Mime.MediaTypeNames.Image.FromFile("SampImag.jpg");
System.Net.Mime.MediaTypeNames.Image temImag = FormatImage(newImage, 100, 100);
//image size modification unction
public static System.Net.Mime.MediaTypeNames.Image FormatImage(System.Net.Mime.MediaTypeNames.Image img, int outputWidth, int outputHeight)
{
Bitmap outputImage = null;
Graphics graphics = null;
try
{
outputImage = new Bitmap(outputWidth, outputHeight, System.Drawing.Imaging.PixelFormat.Format16bppRgb555);
graphics = Graphics.FromImage(outputImage);
graphics.DrawImage(img, new Rectangle(0, 0, outputWidth, outputHeight),
new Rectangle(0, 0, img.Width, img.Height), GraphicsUnit.Pixel);
return outputImage;
}
catch (Exception ex)
{
return img;
}
}
其他回答
使用下面的函数和下面的例子来改变图像大小:
//Example :
System.Net.Mime.MediaTypeNames.Image newImage = System.Net.Mime.MediaTypeNames.Image.FromFile("SampImag.jpg");
System.Net.Mime.MediaTypeNames.Image temImag = FormatImage(newImage, 100, 100);
//image size modification unction
public static System.Net.Mime.MediaTypeNames.Image FormatImage(System.Net.Mime.MediaTypeNames.Image img, int outputWidth, int outputHeight)
{
Bitmap outputImage = null;
Graphics graphics = null;
try
{
outputImage = new Bitmap(outputWidth, outputHeight, System.Drawing.Imaging.PixelFormat.Format16bppRgb555);
graphics = Graphics.FromImage(outputImage);
graphics.DrawImage(img, new Rectangle(0, 0, outputWidth, outputHeight),
new Rectangle(0, 0, img.Width, img.Height), GraphicsUnit.Pixel);
return outputImage;
}
catch (Exception ex)
{
return img;
}
}
下面的函数将返回显示图像的新大小。这在这里可能没有帮助。但它将返回调整大小的显示矩形大小。
public static class ResizeImage
{
/// <summary>
/// Return new resized size to display the image
/// </summary>
/// <param name="srcrectanle">source rectangle of image or you can pass the bitmap and set the size accrodingly</param>
/// <param name="initSize">initial size of the page to draw image</param>
/// <returns></returns>
public static SizeF getResizedRectangle(RectangleF srcrectanle, SizeF initSize)
{
float sw = srcrectanle.Width;
float sh = srcrectanle.Height;
float dw = initSize.Width;
float dh = initSize.Height;
float finalHeight, finalWidth;
float Sourceratio = sw / sh;
if (Sourceratio >= 1)
{
finalWidth = (int)dw;
float ratio = sw / dw;
finalHeight = (sh / ratio);
}
else
{
finalHeight = (int)dh;
float ratio = sh / dh;
finalWidth = (sw / ratio);
}
return new SizeF(finalHeight, finalHeight);
}
}
不知道这有什么困难,做你正在做的,使用重载Bitmap构造函数来创建一个重新大小的图像,你唯一缺少的是转换回image数据类型:
public static Image resizeImage(Image imgToResize, Size size)
{
return (Image)(new Bitmap(imgToResize, size));
}
yourImage = resizeImage(yourImage, new Size(50,50));
为什么不用System.Drawing.Image.GetThumbnailImage方法呢?
public Image GetThumbnailImage(
int thumbWidth,
int thumbHeight,
Image.GetThumbnailImageAbort callback,
IntPtr callbackData)
例子:
Image originalImage = System.Drawing.Image.FromStream(inputStream, true, true);
Image resizedImage = originalImage.GetThumbnailImage(newWidth, (newWidth * originalImage.Height) / originalWidth, null, IntPtr.Zero);
resizedImage.Save(imagePath, ImageFormat.Png);
来源: http://msdn.microsoft.com/en-us/library/system.drawing.image.getthumbnailimage.aspx
本遗嘱-
调整宽度和高度,不需要循环 不超过图像的原始尺寸
//////////////
private void ResizeImage(Image img, double maxWidth, double maxHeight)
{
double resizeWidth = img.Source.Width;
double resizeHeight = img.Source.Height;
double aspect = resizeWidth / resizeHeight;
if (resizeWidth > maxWidth)
{
resizeWidth = maxWidth;
resizeHeight = resizeWidth / aspect;
}
if (resizeHeight > maxHeight)
{
aspect = resizeWidth / resizeHeight;
resizeHeight = maxHeight;
resizeWidth = resizeHeight * aspect;
}
img.Width = resizeWidth;
img.Height = resizeHeight;
}