给定一张图片URL判断图片的大小和类型：FastImage

jopen 10年前

这是一个优秀 Ruby 库FastImage通过获取尽可能少的内容，对给定的一张图片URI来判断图片的大小和类型。

特性

Fastimage还能够读取本地文件，使用Addressable库来实现。

FastImage will automatically read from any object that responds to :read – for
  instance an IO object if that is passed instead of a URI.

FastImage会跟进至4 HTTP重定向来获得图像。

FastImage will obey the http_proxy setting in your environment to route requests via a proxy.

You can add a timeout to the request which will limit the request time by passing :timeout => number_of_seconds.

FastImage normally replies will nil if it encounters an error, but you can pass :raise_on_failure => true to get an exception.

FastImage.size("http://stephensykes.com/images/ss.com_x.gif")  => [266, 56]  # width, height  FastImage.type("http://stephensykes.com/images/pngimage")  => :png  FastImage.type("/some/local/file.gif")  => :gif  FastImage.size("http://upload.wikimedia.org/wikipedia/commons/b/b4/Mardin_1350660_1350692_33_images.jpg", :raise_on_failure=>true, :timeout=>0.1)  => FastImage::ImageFetchFailure: FastImage::ImageFetchFailure  FastImage.size("http://upload.wikimedia.org/wikipedia/commons/b/b4/Mardin_1350660_1350692_33_images.jpg", :raise_on_failure=>true, :timeout=>2.0)  => [9545, 6623]
github项目地址：https://github.com/sdsykes/fastimage


Python语言实现版：
https://github.com/bmuller/fastimage

用法

This assumes you have a working familiarity with Twisted.

Usage is pretty dang simple.

from fastimage import get_size  from twisted.internet import reactor    def handle(result):      width, height = result      print "Size: ", width, "x", height      reactor.stop()    url = "http://stephensykes.com/images/ss.com_x.gif"  get_size(url).addCallbacks(handle)  reactor.run()
which will poop out:
Size:  266 x 56

You can also just get the image type:

from fastimage import get_type  from twisted.internet import reactor    def handle(result):      print "Type:", result      reactor.stop()    url = "http://stephensykes.com/images/ss.com_x.gif"  get_type(url).addCallbacks(handle)  reactor.run()

which will poop out:

Type: gif

Right now, sizes can be deduced from gif / jpg / png. Additionally, it can detect the type (but not size) of bmp / tiff.