如何將未知尺寸的圖像調整爲特定尺寸而沒有太多變形？

Question

我想從用戶那裏獲取圖像並將其重新調整爲特定尺寸，但問題是： 我不知道用戶的圖像尺寸，我必須將尺寸重新調整爲特定尺寸，但變形是這裏的負擔。

我該如何解決這個問題？有什麼算法嗎？ 或有任何源代碼最好在.net？ 此致敬意。

Answer 1

就變形而言，可以使用裁剪和調整大小的組合。您的用戶可以幫助您裁剪。

我發現這個代碼在Code Project用一個簡單的谷歌搜索的.net resize an image

imgPhoto = FixedSize(imgPhotoVert, 300, 300); 
imgPhoto.Save(WorkingDirectory + 
    @"\images\imageresize_3.jpg", ImageFormat.Jpeg); 
imgPhoto.Dispose(); 
.... 
static Image FixedSize(Image imgPhoto, int Width, int Height) 
{ 
    int sourceWidth = imgPhoto.Width; 
    int sourceHeight = imgPhoto.Height; 
    int sourceX = 0; 
    int sourceY = 0; 
    int destX = 0; 
    int destY = 0; 

    float nPercent = 0; 
    float nPercentW = 0; 
    float nPercentH = 0; 

    nPercentW = ((float)Width/(float)sourceWidth); 
    nPercentH = ((float)Height/(float)sourceHeight); 
    if(nPercentH < nPercentW) 
    { 
     nPercent = nPercentH; 
     destX = System.Convert.ToInt16((Width - 
         (sourceWidth * nPercent))/2); 
    } 
    else 
    { 
     nPercent = nPercentW; 
     destY = System.Convert.ToInt16((Height - 
         (sourceHeight * nPercent))/2); 
    } 

    int destWidth = (int)(sourceWidth * nPercent); 
    int destHeight = (int)(sourceHeight * nPercent); 

    Bitmap bmPhoto = new Bitmap(Width, Height, 
         PixelFormat.Format24bppRgb); 
    bmPhoto.SetResolution(imgPhoto.HorizontalResolution, 
        imgPhoto.VerticalResolution); 

    Graphics grPhoto = Graphics.FromImage(bmPhoto); 
    grPhoto.Clear(Color.Red); 
    grPhoto.InterpolationMode = 
      InterpolationMode.HighQualityBicubic; 

    grPhoto.DrawImage(imgPhoto, 
     new Rectangle(destX,destY,destWidth,destHeight), 
     new Rectangle(sourceX,sourceY,sourceWidth,sourceHeight), 
     GraphicsUnit.Pixel); 

    grPhoto.Dispose(); 
    return bmPhoto; 
}