车东[Blog^2]

上次看到Google的新版本抓图，

就一直在想他是怎么把需要滚这么多屏的网页抓成一个图的？

在网上找了2个多小时，后来无意中发现（正如楼下所说，是在搜索的时候，看到文章发现SnagIt有类似功能，联想到常用的Hypersnap……）其实多屏抓取是我最熟悉的HyperSnap（我用的是3.x Basic，才500多K，如果需要PNG等更多格式的支持需要3.x Pro版本，大约1.1M）本身就能实现的一个基本功能：
注意到了吗：Google那个图是连外面的窗体也包括的，但是HyperSnap的这个滚屏能只抓取某个内容框内那一帧的内容。

在HyperSnap包含一个自动滚屏模式选项：
在菜单的Capture==> auto scroll windows选项被启用后，只要在Active Window抓取模式（快捷方式是：ctrl+shift+w）下选定抓取窗口后时候按下左键（此时鼠标已经有了一个向下箭头），当前屏幕就会自动PageDown地一页一页往下翻，一直翻到底后多屏幕网页内容就被抓取成了一个图片。

关于Auto Scroll的帮助原文：
Auto Scroll Window (Capture)

This unique option gives you the ability to scroll down during a Capture|Window session, to capture data beyond what is immediately visible in a window with a vertical scroll bar.
Auto Scroll always starts from the top and moves downward. The following step-by-step instructions may help you understand how it works:

1. Set the target window containing the vertical scroll bar to the top of its page, or to the area where you want to start capturing.
2. Move to the HyperSnap-DX window and click on Capture menu to be certain that the Auto-Scroll Window menu item has a check mark to the left of it. If not, click on Auto-Scroll Window and reopen the menu again to verify that it does.
3. When you select Window from the Capture menu, HyperSnap-DX will disappear. Move your cursor to the window that you want to capture using auto-scroll, and click within the window. Then, observe how HyperSnap-DX automatically scrolls it as it captures. If you want to end the capture early, click again; otherwise wait until it it is finished.

Note: Auto-Scroll will not work with every application using a vertical scroll bar. Some applications interfere with the methods HyperSnap-DX uses to track the window. The system will display an error message to alert you. However, the most popular web browsers (Netscape Navigator/Communicator and Microsoft Internet Explorer) as well as most other programs we tested are compatible.

This function is ideal for capturing entire web page images, such as with Netscape or Internet Explorer, and file listings, too.
这个功能对于抓取整个网页非常有用：如IE或Netscape，还有资源管理器的文件列表；
以下是我抓取的Google搜索结果页面：

另外还有个窍门：先调好窗口大小再抓图，避免使用工具缩放愿图大小
用HyperSnap抓取下来的图如果因为太宽需要再用AcdSee之类的工具改变幅面效果就会很差，解决的方法是抓取的时候，就把窗口缩小，并调整成需要的幅面。

关于图片存储格式：对于不需要动画来说，PNG可能是还原效果最好的格式了，正如楼下Platinum朋友所说：PNG 支持 32 位色、算法公开没有专利权问题（尽管 GIF 也快没有了），他是开源的（这点非常重要）。