You have your choice of these image enhancements:

affine

affine transform image. The parameter has this format:

    sx, rx, ry, sy, tx, ty

Crop

preferred size and location of the cropped image. The parameter has this format:

    <width>x<height>{+-}<x offset>{+-}<y offset>{%}

For example, 100x200+20+10.

To specify a percentage width or height instead, append %. For example to crop the image by ten percent on all sides of the image, use 10%.

Use cropping to apply image processing options to, or display, a particular area of an image. Omit the x and y offset to generate one or more subimages of a uniform size.

Chop

preferred size and location of the chopped image. See crop for the parameter requirements. Use this transform to remove a section of the image from it's interior. If you remove from the exterior of the image, chop behaves like crop.

Coalesce

merge a sequence of images. Requires an image sequence.

Deconstruct

break down an image sequence into constituent parts. Requires an image sequence.

Flip

create a mirror image by reflecting the image scanlines in the vertical direction.

Flop

create a mirror image by reflecting the image scanlines in the horizontal direction.

Rotate right

rotate the image right 90 degrees.

Rotate left

rotate the image right -90 degrees.

Rotate

apply Paeth image rotation to the image. The parameter has this format:

    degrees{<}{>}

Use > to rotate the image only if its width exceeds the height. < rotates the image only if its width is less than the height. For example, if you specify -90> and the image size is 480x640, the image is not rotated by the specified angle. However, if the image is 640x480, it is rotated by -90 degrees.

Shave

shave pixels from the image edges. The parameter has this format:

    <width>x<height>

Shear

shear the image along the X or Y axis by a positive or negative shear angle. The parameter has this format:

    <x degrees>x<y degrees>

Shearing slides one edge of an image along the X or Y axis, creating a parallelogram. An X direction shear slides an edge along the X axis, while a Y direction shear slides an edge along the Y axis. The amount of the shear is controlled by a shear angle. For X direction shears, x degrees is measured relative to the Y axis, and similarly, for Y direction shears y degrees is measured relative to the X axis.

Roll

roll an image vertically or horizontally. The parameter has this format:

    {+-}<x offset>{+-}<y offset>

A negative x offset rolls the image left-to-right. A negative y offset rolls the image top-to-bottom.

Trim

remove edges that are the background color.