jpegtran.exe_在Mac或Unix / Linux上安装JPEGTRAN

jpegtran.exe

JPEGtran is cool because it lets you optimize JPEG images losslessly by:

JPEGtran很酷，因为它可以让您通过以下方法无损优化JPEG图像：

1. Stripping meta data (meta is sometimes bulky and useless for web display)
   剥离元数据(元数据有时很庞大，对于Web显示无用)
2. Optimizing Huffman tables or
   优化霍夫曼表或
3. Convert a JPEG to progressive encoding
   将JPEG转换为逐行编码

From my experience 1 is more important than 2 or 3 and 3 gives better results than 2 for images over 10K

根据我的经验，对于10K以上的图像， 1比2或3更重要，而3比2的效果更好

安装(Installation)

I never had to install jpegtran before because all unix/linux machines I've touched already have it. And on windows you just copy a binary somewhere in your path.

我以前从未安装过jpegtran，因为我接触过的所有unix / linux机器都已经安装了它。 在Windows上，您只需将二进制文件复制到路径中的某个位置即可。

Well, I got this MacBook now and it doesn't have jpegtran so had to figure it out myself. Here's how you can do it, worked for me on Mac OS should work on any unix/linux too.

好吧，我现在有了这款MacBook，它没有jpegtran，所以必须自己弄清楚。 在Mac OS上为我工作的方法如下：

BTW, jpegtran is part of a package of few tools known as libjpeg, so you'll be installing a few programs not only jpegtran.

顺便说一句，jpegtran是一些称为libjpeg的工具的一部分，因此您将安装一些程序，不仅是jpegtran。

1. Get the source code from here. It's the file called jpegsrc.v6b.tar.gz. Using cURL you can download like:

   从此处获取源代码。 这是名为jpegsrc.v6b.tar.gz的文件。 使用cURL，您可以像这样下载：

   curl http://www.ijg.org/files/jpegsrc.v6b.tar.gz > /tmp/libjpeg.tar.gz

   curl http://www.ijg.org/files/jpegsrc.v6b.tar.gz > /tmp/libjpeg.tar.gz

2. Uncompres the package, e.g. tar -xzvf /tmp/libjpeg.tar.gz

   解压缩该软件包，例如tar -xzvf /tmp/libjpeg.tar.gz

3. go to the directory that contains the uncompressed code, e.g. cd /tmp/jpeg-6b

   转到包含未压缩代码的目录，例如cd /tmp/jpeg-6b

4. ./configure

   ./configure

5. sudo make install

   sudo make install

Done.

做完了

You can test your shiny new set of tools like this and get some help information about the various options:

您可以像这样测试新的闪亮工具集，并获得有关各种选项的一些帮助信息：

> jpegtran -h
> cjpeg -h
> djpeg -h
> rdjpgcom -h
> wrjpgcom -h

You also test by optimizing my book cover from Amazon like:

您还可以通过优化我的亚马逊书籍封面进行测试，例如：

curl http://ecx.images-amazon.com/images/I/41ckBp3bBUL._SL500_AA240_.jpg > oojs.jpg
jpegtran -copy none -progressive oojs.jpg > oojs-opt.jpg

This gives you 10% smaller file with not a pixel of quality loss. Not bad, eh, for a minute of work, or less.

这样可以使文件小10％，而不会降低质量。 不错，嗯，花一分钟或更短的时间。

Tell your friends about this post on Facebook and Twitter

在Facebook和Twitter上告诉您的朋友有关此帖子的信息

翻译自: https://www.phpied.com/installing-jpegtran-mac-unix-linux/

jpegtran.exe