How to get information about an image (picture) from the Linux command-line?

Solution 1:

For some image formats you can just use the file command:

$ file MyPNG.png 
MyPNG.png: PNG image, 681 x 345, 8-bit/color RGB, non-interlaced

Not all image formats report the size (JPEG most notably doesn't):

$ file MyJpeg.jpg 
MyJpeg.jpg: JPEG image data, JFIF standard 1.01

For those you will have to use something more elaborate, like:

$ convert MyJpeg.jpg -print "Size: %wx%h\n" /dev/null
Size: 380x380

The convert command is part of the ImageMagick package.

Solution 2:

The best way to get this information is by using the identify command:

$ identify image.png

or only size attributes

$ identify -format "%wx%h" photo.jpg

It is part of ImageMagick, which you can install on Ubuntu like so:

$ sudo apt-get install imagemagick

Solution 3:

exiv2 is "the tool" to get information from picture files:

~$exiv2 myimage.jpg

outputs:

File name       : myimage.jpg
File size       : 1196944 Bytes
MIME type       : image/jpeg
Image size      : 2592 x 1944
Camera make     : LG Electronics
Camera model    : LG-P970
Image timestamp : 2013:05:19 17:27:06
Image number    : 
Exposure time   : 1/9 s
Aperture        : 
Exposure bias   : 0 EV
Flash           : Yes, compulsory
Flash bias      : 
Focal length    : 3.7 mm
Subject distance: 
ISO speed       : 745
Exposure mode   : 
Metering mode   : Average
Macro mode      : 
Image quality   : 
Exif Resolution : 
White balance   : Auto
Thumbnail       : image/jpeg, 13776 Bytes
Copyright       : 
Exif comment    :

Solution 4:

Also, check out ExifTool by Phil Harvey; an example:

$ exiftool test.png 
ExifTool Version Number         : 8.15
File Name                       : test.png
Directory                       : .
File Size                       : 12 MB
File Modification Date/Time     : 2014:02:13 13:04:52+01:00
File Permissions                : rw-r--r--
File Type                       : PNG
MIME Type                       : image/png
Image Width                     : 2490
Image Height                    : 3424
Bit Depth                       : 8
Color Type                      : RGB
Compression                     : Deflate/Inflate
Filter                          : Adaptive
Interlace                       : Noninterlaced
Significant Bits                : 8 8 8
Image Size                      : 2490x3424

Btw, I was looking to get information on dpi/resolution from the command line; and interestingly, sometimes none of these tools report that in an image (like in the above snippet); for more on that, see I want to change DPI with Imagemagick without changing the actual byte-size of the image data - Super User - however, identify -verbose seems to work for the same image as in the previous snippet:

$ identify -verbose test.png 
Image: test.png
  Format: PNG (Portable Network Graphics)
  Class: DirectClass
  Geometry: 2490x3424+0+0
  Resolution: 72x72
  Print size: 34.5833x47.5556
  Units: Undefined
  Type: TrueColor
  Endianess: Undefined
  Colorspace: RGB
  Depth: 8-bit
  Channel depth:
    red: 8-bit
    green: 8-bit
    blue: 8-bit
  Channel statistics:
    Red:
      min: 8 (0.0313725)
      max: 255 (1)
      mean: 237.541 (0.931533)
      standard deviation: 37.2797 (0.146195)
      kurtosis: 21.2876
      skewness: -4.56853
    Green:
      min: 15 (0.0588235)
      max: 255 (1)
      mean: 240.007 (0.941204)
      standard deviation: 37.8264 (0.148339)
      kurtosis: 20.7241
      skewness: -4.51584
    Blue:
      min: 9 (0.0352941)
      max: 255 (1)
      mean: 240.349 (0.942547)
      standard deviation: 38.7118 (0.151811)
      kurtosis: 22.255
      skewness: -4.72275
  Image statistics:
    Overall:
      min: 8 (0.0313725)
      max: 255 (1)
      mean: 179.474 (0.703821)
      standard deviation: 108.711 (0.426316)
      kurtosis: -0.958865
      skewness: -0.995795
  Rendering intent: Undefined
  Interlace: None
  Background color: white
  Border color: rgb(223,223,223)
  Matte color: grey74
  Transparent color: black
  Compose: Over
  Page geometry: 2490x3424+0+0
  Dispose: Undefined
  Iterations: 0
  Compression: Zip
  Orientation: Undefined
  Properties:
    date:create: 2014-02-13T13:11:08+01:00
    date:modify: 2014-02-13T13:04:52+01:00
    signature: bada990d3ba29b311501146d9013d67cf36f667c6d39b1f28a72ce913924397d
  Artifacts:
    verbose: true
  Tainted: False
  Filesize: 12.52MB
  Number pixels: 8.526M
  Pixels per second: 7.894M
  User time: 1.080u
  Elapsed time: 0:02.080
  Version: ImageMagick 6.6.2-6 2012-08-17 Q16 http://www.imagemagick.org

... although, it can be a bit tricky to read resolution in units of PixelsPerInch using identify -verbose - see ImageMagick • View topic - Cannot set units to pixelsperinch?.