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[Example Usage • Option Summary]

The identify program describes the format and characteristics of one or more image files. It also reports if an image is incomplete or corrupt. The information returned includes the image number, the file name, the width and height of the image, whether the image is colormapped or not, the number of colors in the image, the number of bytes in the image, the format of the image (JPEG, PNM, etc.), and finally the number of seconds it took to read and process the image. Many more attributes are available with the verbose option. See Command Line Processing for advice on how to structure your identify command or see below for example usages of the command.

We list a few examples of the identify command here to illustrate its usefulness and ease of use. To get started, lets identify an image in the JPEG format:

  identify rose.jpg
  rose.jpg JPEG 640x480 DirectClass 87kb 0.050u 0:01

Next, we look at the same image in greater detail:

  identify -verbose rose.jpg
  Image: rose.jpg
    Format: JPEG (Joint Photographic Experts Group JFIF format)
    Class: DirectClass
    Geometry: 70x46+0+0
    Type: TrueColor
    Endianess: Undefined
    Colorspace: RGB
    Depth: 8-bit
    Channel depth:
      Red: 8-bit
      Green: 8-bit
      Blue: 8-bit
    Channel statistics:
      Red:
        Min: 30 (0.117647)
        Max: 255 (1)
        Mean: 145.389 (0.570155)
        Standard deviation: 67.3859 (0.264259)
      Green:
        Min: 29 (0.113725)
        Max: 255 (1)
        Mean: 89.1997 (0.349803)
        Standard deviation: 51.9245 (0.203626)
      Blue:
        Min: 15 (0.0588235)
        Max: 255 (1)
        Mean: 80.3752 (0.315197)
        Standard deviation: 53.351 (0.209219)
    Rendering intent: Undefined
    Resolution: 72x72
    Units: PixelsPerInch
    Filesize: 1.54297kb
    Interlace: None
    Background color: white
    Border color: rgb(223,223,223)
    Matte color: grey74
    Transparent color: black
    Page geometry: 70x46+0+0
    Dispose: Undefined
    Iterations: 0
    Compression: JPEG
    Quality: 85
    Orientation: Undefined
    Jpeg:colorspace: 2
    Jpeg:sampling-factor: 2x2,1x1,1x1
    Signature: 9273d04d56681f833fbf1a08cab0702723ff2ba31b78813fcd4e67e082f5fad6
    Tainted: False
    Version: ImageMagick 6.3.7 11/01/07 Q16 http://www.imagemagick.org

To get the print size in inches of an image at 72 DPI, use:

  identify -format "%[fx:w/72] by %[fx:h/72] inches" document.png
  8.5 x 11 inches

The depth and dimensions of a raw image must be specified on the command line:

  identify -depth 8 -size 640x480 image.raw
  rose.rgb RGB 70x46 DirectClass 9kb 0.000u 0:01

You can find additional examples of using identify in Examples of ImageMagick Usage.

The identify command recognizes these options. Click on an option to get more details about how that option works.