Full Command Reference

Full Command Reference

Selecting a frame or page

  • frame=x – Choose which frame of an animated GIF to display.
  • page=x– Choose which page of a multi-page TIFF document to display.

Rotation & flipping

  • autorotate=true Automatically rotates the image based on the EXIF info from the camera. autorotate.default=true will only autorotate if the image is processed.
  • sflip=none|x|y|xy Flips the source image prior to processing (new in V3.1).
  • srotate=0|90|180|270 Rotates the source image prior to processing (only 90 degree intervals) (new in V3.1).
  • rotate=degrees – Rotates the image any arbitrary angle (occurs after cropping).
  • flip=none|x|y|xy - Flips the image after everything is done.

Manual cropping

  • crop=(x1,y1,x2,y2) – Crop the image to the specified rectangle on the source image. You can use negative coordinates to specify bottom-right relative locations.
  • cropxunits The width which the x1 and x2 coordinates are relative to, e.g., use '100' to make x1 and x2 percentages. Useful when you don't know the original image size.
  • cropyunits The height which the y1 and y2 coordinates are relative to, e.g., use '100' to make y1 and y2 percentages. Useful when you don't know the original image size.

Sizing (and padding, autocropping, carving and stretching)

Please note that width/height/maxwidth/maxheight do NOT include border, margin, or padding widths, and do not include the extra space used by rotation. They constrain the image, not the canvas.

  • maxwidth, maxheight – Fit the image within the specified bounds, preserving aspect ratio.
  • width, height – Force the final width and/or height to certain dimensions. Whitespace will be added if the aspect ratio is different.
  • mode=max|pad|crop|carve|stretch - How to handle aspect-ratio conflicts between the image and width+height. 'pad' adds whitespace, 'crop' crops minimally, 'carve' uses seam carving, 'stretch' loses aspect-ratio, stretching the image. 'max' behaves like maxwidth/maxheight (new in V3.1).
  • anchor=topleft|topcenter|topright|middleleft|middlecenter|middleright|bottomleft|bottomcenter|bottomright How to anchor the image when padding or cropping (new in V3.1).
  • scale=both|upscaleonly|downscaleonly|upscalecanvas – By default, images are never upscaled. Use &scale=both to upscale images if they are smaller than width and height.
  • zoom=0..infinity - Scale the image by a multiplier. Useful for mobile devices and situations where you need to retain all the existing width/height/crop settings, but scale the result up or down. Defaults to 1. 0.5 produces a half-size image, 2 produces a double-size image.

Border, padding, margins and background colors

  • bgcolor=color name | hex code (6-char). Sets the background/whitespace color.
  • paddingWidth=px & paddingColor=color|hex paddingColor defaults to bgcolor, which defaults to white.
  • borderWidth=px, borderColor=color|hex borderColor defaults to transparent.
  • margin=3 or margin=5,5,10,10 Specify a universal margin or left,top,right,bottom widths (new in V3.1.

Output format

  • format=jpg|png|gif - The output format to use.
  • quality - Jpeg compression: 0-100 100=best, 90=very good balance, 0=ugly.
  • colors=2-255 – Control the palette size of PNG and GIF images. If omitted, PNGs will be 24-bit (PrettyGifs plugin required).


  • ignoreicc - true|false. If true, the ICC profile embedded in the source image will be ignored.
  • cache - always|no|default - Always forces the image to be cached even if it wasn't modified by the resizing module. Doesn't disable caching if it was modified.
  • process - always|no|default - Always forces the image to be re-encoded even if it wasn't modified. Does not prevent the image from being modified.
  • dpi=90|300|600 - The DPI at which the image should be printed. Ignored by all browsers, most operating systems, and most printers.

Watermark plugin

  • watermark - The name of one or more watermark layers (or layer groups) to render.

Image404 plugin

  • 404 - The path to the fallback image, or a named preset.

Gradient plugin

  • color1,color2 - 6 or 8 digit hex values specifying the start and end gradient colors.
  • angle - 0 is horizontal. Degrees to rotate the gradient.
  • width/height - The size of the gradient image.

PrettyGifs plugin

  • colors - 2 to 256 (the number of colors to allow in the output image palette). For Gifs and 8-bit PNGs.
  • dither=true|false|4pass|30|50|79|[percentage] - How much to dither.

SimpleFilters plugin

  • &s.grayscale=true|y|ry|ntsc|bt709|flat (true, ntsc, and y produce identical results)
  • &s.sepia=true
  • &s.alpha= 0..1
  • &s.brightness=-1..1
  • &s.contrast=-1..1
  • &s.saturation=-1..1
  • &s.invert=true

AdvancedFilters plugin

  • &a.blur=radius - Gaussian blur with adjustable radius.
  • &a.sharpen=radius - Gaussian sharpen with adjustable radius.
  • &a.contrast=-1..1
  • &a.saturation=-1..1
  • &a.brightness=-1..1
  • &a.equalize=true - Adjusts contrast, saturation, and brightness with curves based on the histogram. Good for adjusting slightly foggy or dark daytime photos.
  • &a.sepia=true - Sepia effect, slightly different from the one in SimpleFilters.
  • &a.oilpainting=1..100 -Try 1 for impressionist, 100 for modern art :)
  • &a.removenoise=1-100 - Not a blur effect - designed to remove color noise, 'pepper noise'. Very conservative, doesn't affect edges.

DropShadow plugin

  • shadowWidth - Width of the shadow.
  • shadowOffset - (x,y) how to offset the drop shadow.
  • shadowColor - Named or hex color of the shadow.

SpeedOrQuality plugin

  • speed=0..5 - The amount of quality to sacrifice for speed - each value uses different settings and techniques, and may not support all features.

Presets plugin

  • preset=name1,name2,name3 - A list of preset settings groups to apply.

WhitespaceTrimmer plugin

  • trim.threshold=80 - The threshold to use for trimming whitespace.
  • trim.percentpadding=0.5 - The percentage of padding to restore after trimming.

WicBuilder & FreeImageBuilder

  • builder=freeimage|wic - Enables the FreeImage or Wic pipeline instead of the default GDI pipeline. Special effect plugins not supported.

FreeImageDecoder, WicDecoder

These act as fallback decoders, but you can tell them to try first by using

  • decoder=wic|freeimage

FreeImageEncoder, WicEncoder

In addition to jpeg quality and gif/png colors, you can configure the jpeg subsampling for both Wic and FreeImage.

  • subsampling==444|422|420