If you need to determine information about an image file from the command line on a Mac OS X system, you can use the
file
command.
If you wanted information about all of the .jpg and .png files in
a directory, you could use the command file *.png *.jpg
$ file *.png *.jpg upgrade-windows-grayed.png: PNG image, 256 x 256, 8-bit/color RGBA, non-interlaced Vista_Install_Type_Product_Key.jpg: JPEG image data, JFIF standard 1.01
For some image files, the file command will show the
image dimensions. The command will reveal the actual image type, even if
a file has been given the wrong extension as shown below.
$ cp Vista_Install_Type_Product_Key.jpg test.png $ file test.png test.png: JPEG image data, JFIF standard 1.01
Another useful utility for determining the dimensions of an image file
is sips. You can use the -g pixelHeight and
-g pixelWidth options to obtain the dimensions of an image.
$ sips -g pixelHeight -g pixelWidth example.jpg /Users/jsmith/Documents/example.jpg pixelHeight: 600 pixelWidth: 800
References:
-
Get the dimensions of most images from the command line UNIX
Date: December 1, 2003
Mac OS X Hints
