Question

我正在检查图像文件的大小，如果文件很大，那么我会重新调整它的大小，以便处理更快。但是当我使用调整大小代码时，我总是得到一个指向image的空引用异常。我试过调试 - ＆gt;返回的已调整大小的位图不是null，而是转换后的图像＆gt; image = new Image（x）; 为null。如果删除resize函数，代码工作正常。

Image<Bgr, byte> image = null;

foreach (string s in mylist)
{
    Bitmap x = new Bitmap(Bitmap.FromFile(s));
    if (x.Width > 1000 || x.Height > 1000)
    {
        x = ResizekeepAspectRatio(x, 1000, 1000);
        image = new Image<Bgr, byte>(x);

    }
    else
    {
        image = new Image<Bgr, byte>(x);
    }

    work(image, x, s);
}

----------------------------------------------------------------------

Bitmap ResizekeepAspectRatio(Bitmap 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;
}

Answer 1

我无法复制错误。我传递了一堆图像并将它们保存出去，但它们都能正确保存 - 即使是那些重新调整大小的图像。

这让我觉得它必须是某些特定的图像失败，或者它可能是Emgu的配置问题。

您可以发布失败的图片吗？

Image <bgr，byte =“”>始终返回Null

1 个答案: