protected virtual bool IsSameSrcImage(ImageResizeUtil other)
{
if (other != null)
{
return(File == other.File &&
Image == other.Image);
}
return(false);
}
/// <summary>
/// Check whether the required destination image properties have
/// changed
/// </summary>
/// <param name="other"></param>
/// <returns></returns>
protected virtual bool IsSameDstImage(ImageResizeUtil other)
{
if (other != null)
{
return(Width == other.Width &&
Height == other.Height &&
UsePercentages == other.UsePercentages &&
PreserveAspectRatio == other.PreserveAspectRatio);
}
return(false);
}
public virtual Image GetThumbnail()
{
// Flag whether a new image is required
bool recalculate = false;
recalculate = IsInCache(recalculate);
double new_width = Width;
double new_height = Height;
if (!IsSameDstImage(_cache))
{
CalucateWidthAndHeight(ref new_height, ref new_width);
recalculate = true;
}
if (recalculate)
{
// Calculate the new image
if (_dstImage != null)
{
_dstImage.Dispose();
_graphics.Dispose();
}
Bitmap bitmap = new Bitmap((int)new_width, (int)new_height, _srcImage.PixelFormat);
_graphics = Graphics.FromImage(bitmap);
_graphics.SmoothingMode = SmoothingMode.HighQuality;
_graphics.InterpolationMode = InterpolationMode.HighQualityBicubic;
_graphics.DrawImage(_srcImage, 0, 0, bitmap.Width, bitmap.Height);
_dstImage = bitmap;
// Cache the image and its associated settings
_cache = MemberwiseClone() as ImageResizeUtil;
}
return(_dstImage);
}
