$convert -resize 320x256 woman.bmp woman320x256.png

$identify -verbose woman320x256.png

Image: woman320x256.png
  Format: PNG (Portable Network Graphics)
  Class: DirectClass
  Geometry: 205x256+0+0
  Resolution: 37.79x37.79
  Print size: 5.42472x6.77428
  Units: PixelsPerCentimeter
  Type: TrueColor
  Endianess: Undefined
  Colorspace: sRGB
  Depth: 8-bit
  Channel depth:
    red: 8-bit
    green: 8-bit
    blue: 8-bit
  Channel statistics:
    Red:
      min: 0 (0)
      max: 255 (1)
      mean: 137.853 (0.540599)
      standard deviation: 67.241 (0.26369)
      kurtosis: -0.774067
      skewness: -0.333761
    Green:
      min: 0 (0)
      max: 255 (1)
      mean: 117.199 (0.459604)
      standard deviation: 60.9243 (0.238919)
      kurtosis: -0.850306
      skewness: -0.331505
    Blue:
      min: 0 (0)
      max: 255 (1)
      mean: 115.844 (0.454291)
      standard deviation: 56.9166 (0.223202)
      kurtosis: -0.756114
      skewness: -0.255542
  Image statistics:
    Overall:
      min: 0 (0)
      max: 255 (1)
      mean: 123.632 (0.484831)
      standard deviation: 61.8402 (0.242511)
      kurtosis: -0.631232
      skewness: -0.247852
  Rendering intent: Perceptual
  Gamma: 0.45455
  Chromaticity:
    red primary: (0.64,0.33)
    green primary: (0.3,0.6)
    blue primary: (0.15,0.06)
    white point: (0.3127,0.329)
  Interlace: None
  Background color: white
  Border color: srgb(223,223,223)
  Matte color: grey74
  Transparent color: black
  Compose: Over
  Page geometry: 205x256+0+0
  Dispose: Undefined
  Iterations: 0
  Compression: Zip
  Orientation: Undefined
  Properties:
    date:create: 2017-04-07T23:11:28+09:00
    date:modify: 2017-04-07T23:11:28+09:00
    png:bKGD                 : chunk was found (see Background color, above)
    png:cHRM                 : chunk was found (see Chromaticity, above)
    png:gAMA                 : gamma=0.45454544 (See Gamma, above)
    png:IHDR.bit_depth       : 8
    png:IHDR.color_type      : 2 (Truecolor)
    png:IHDR.interlace_method: 0 (Not interlaced)
    png:IHDR.width,height    : 205, 256
    png:pHYs                 : x_res=3779, y_res=3779, units=1
    png:sRGB                 : intent=0 (See Rendering intent)
    png:text                 : 2 tEXt/zTXt/iTXt chunks were found
    signature: bb30e9a8bbd0157063dd397a7f75d18a64338e084d2324d296e7a1b12649b445
  Artifacts:
    filename: woman320x256.png
    verbose: true
  Tainted: True
  Filesize: 87.6KB
  Number pixels: 52.5K
  Pixels per second: 5.248MB
  User time: 0.000u
  Elapsed time: 0:01.009
  Version: ImageMagick 6.7.7-10 2017-03-14 Q16 http://www.imagemagick.org

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