最佳调整大小和/或裁剪逻辑

时间:2009-10-26 18:04:03

标签: c# resize logic crop

我偶然发现过几次,并认为把它放在那里会很好。什么是你最好的图像调整大小和/或裁剪逻辑。想法是使用目标图像,尺寸和裁剪标记调用某些方法 - 这将返回或保存或任何所需的图像。

我的下面。从VB转换为C#所以是的,会有小错误,但逻辑是我们正在看的。

// INIT
// On/off
bool WeAreCropping = true;

// Get some dimensions
int TargetWidth = RequestedWidth;
int TargetHeight = RequestedHeight;
int SourceWidth = SourceImage.Width;
int SourceHeight = SourceImage.Height;
int ResizeWidth = TargetWidth;
int ResizeHeight = TargetHeight;

// GET RESIZE VALUES
// Are we cropping?
if (WeAreCropping) {

    // Get source and target aspect ratio
    double SourceAspectRatio = SourceWidth / SourceHeight;
    double TargetAspectRatio = TargetWidth / TargetHeight;

    // Compare aspect ratios to find out if we should we resize by 
    // width or height or nothing
    if (TargetAspectRatio < SourceAspectRatio) {
        ResizeWidth = TargetHeight / SourceHeight * SourceWidth;
    }
    else if (TargetAspectRatio > SourceAspectRatio) {
        ResizeHeight = TargetWidth / SourceWidth * SourceHeight;
    }
    else {
      // Same aspect ratio
    }


}
else {

    // If the target image is bigger than the source
    if (TargetWidth > SourceWidth && TargetHeight > SourceHeight) {
        TargetWidth = SourceWidth;
        TargetHeight = SourceHeight;
    }

    double Ratio = 0;

    // What ratio should we resize it by
    if (SourceWidth / TargetWidth > SourceHeight / TargetHeight) {
        Ratio = SourceWidth / TargetWidth;
    }
    else {
        Ratio = SourceHeight / TargetHeight;
    }

    ResizeWidth = Math.Ceiling(SourceWidth / Ratio);

    ResizeHeight = Math.Ceiling(SourceHeight / Ratio);
}

// TIME TO DO SUMFINK
// Resize the image using ResizeWidth and ResizeHeight
// Do it

if (WeAreCropping) {
    // Crop the resized image at the center TargetWidth and TargetHeight
    // Do it
}

我怀疑这可能会更优雅,所以也许你可以做得更好。

2 个答案:

答案 0 :(得分:4)

我会说你应该使用像RectangleSize这样的标准几何类型。然后你应该也支持一个用例,当调用者想要将图像放在一个更大的矩形中时,但仍然希望保持原始图像大小的比例。

实现调整大小的一种方法是here

答案 1 :(得分:0)

这可能比你需要的更多一些,但是对于一些高级裁剪技术的例子,check this out