我们有一个系统，提供图像的8位灰度TIFF或JPG格式。但是，我们必须处理的图像组件需要的图像是在8位JPG格式。

We have a system that provides images in 8-bit grayscale either tiff or jpg formats. However, the component we have to process the images expects image to be in 8-bit jpg format.

当我使用的.Net保存TIFF图像为jpg它convets到24位的图像。

When I use .Net to save the tiff images as jpg it convets it to 24-bit image.

有没有一种方法，希望能简单快速，8位灰度TIFF图像转换为相当于JPG？

Is there a way, hopefully simple and fast, to convert 8-bit grayscale tiff images to equivalent jpg?

推荐答案

我试了又试刚刚得出结论，我很抱歉：NET库的Bitmap类不JPEG格式保存为8bpp，即使明确地陈述和数据是在灰度

I tried and tried just to conclude that I'm sorry: .Net library's Bitmap class DOES NOT save JPEG as 8bpp even when explicitly stated and data is in grayscale.

（注意：虽然在一些地方规定，JPEG格式不支持8bpp）。

(note: although stated in some places, JPEG format DOES support 8bpp).

在 C＃，转换图像灰度你会发现code snipet转换为灰度的图片。

At C#, convert image to grayscale you may find code snipet to convert to grayscale any Image.

使用code，我能够保存.JPEG扩展名的8bpp灰度图像的实例，但指出ImageFormat.Gif ...这是个骗子......

Using that code, I was able to save a 8bpp grayscale Image instance with '.jpeg' extension, but stating ImageFormat.Gif... that's a cheat...

我的调查结果显示作为解决方案的一个完全不同的方法。

My findings show as solution an entirely different approach.

FreeImage库文件提供了强大的API，其中包括为您解决问题所需要的功能。

The FreeImage library offers powerful APIs, including the feature needed to solve your problem.

它的主页是 http://freeimage.sourceforge.net/faq.html

不过，我是不会轻易在我的Win2008 + VS 2010的机器编译。

But, I could not easily compile it in my Win2008 + VS 2010 machine.

应该有一个人出了很多汗​​，使其在现代环境中运行。

One ought to sweat a lot to make it run on modern environments.

这是如何完成被发现在的http://www.sambeauvois.be/blog/2010/05/freeimage-and-x64-projects-yes-you-can/

Some hints on how to accomplish that are found at http://www.sambeauvois.be/blog/2010/05/freeimage-and-x64-projects-yes-you-can/

祝你好运！