# Contents

**ice.Image LinearTransform(***matrix***)**

This operation performs all coordinate transformations expressible as a 3x3 matrix. These include affine transformations (in which parallel lines stay parallel), translations and non-affine perspective transformations.

The resampling filter is a Catmull-Rom bicubic, whose width is calculated appropriately.

### Parameters

*matrix*

3x3 transformation matrix (list).

### Example

In the example below, i is of type ice.Image.

matrix = [1, 0.3, 0, 0.1, 1, 0, 0, 0, 1.0] result = i.LinearTransform(matrix

**ice.Image Translate(***point, filterType***)**

Translate an image with appropriate resampling. Integral pixel translate operations are automatically optimized.

### Parameters

*point*

Translate by a specified number of pixels (tuple)

*filter*

resampling filter to use (int). Can be one of:

- ice.constants.FILTER_BILINEAR
- ice.constants.FILTER_BSPLINE
- ice.constants.FILTER_CATROM
- ice.constants.FILTER_LANCZOS
- ice.constants.FILTER_MITCHELL_NETRAVALI
- ice.constants.FILTER_POINTSAMPLE

Defaults to FILTER_CATROM (CatmullRom).

### Example

filter = ice.constants.FILTER_BILINEAR amount = (23.5. 60.6) result = orig.Translate(amount, filter)

This is a special case of *LinearTransform.*

**ice.Image Move(***point***)**

Returns a copy of the operand image with its world coordinates moved by an integral amount. The copy will share data with the source, no resampling will be performed

### Parameters

*point*

Move by a specified number of pixels (tuple)

**ice.Image Scale(***scale, filter***)**

Geometrically scale an image with appropriate resampling.

### Parameters

*scale*

Scale by specified factors in x and y (list)

*filter*

resampling filter to use (int). Defaults to CatmullRom.

### Example

filter = ice.constants.FILTER_LANCZOS amount = [0.5. 0.5] result = orig.Scale(amount, filter)

This is a special case of *LinearTransform*.

**ice.Image Rotate(***degrees, filter***)**

Rotate an image about *(0, 0)*. The angle of rotation is measured counterclockwise.

### Parameters

*degrees*

Angle of rotation in degrees (float)

*filter*

resampling filter to use (int). Defaults to CatmullRom

### Example

This is a special case of *LinearTransform.*

**ice.Image Resize(***scale***)**

Fast geometric scaling using only point-sampling. Useful for previews and interactive display.

### Parameters

*scale*

Scale by specified factors in x and y (list)

**ice.Image Reformat(newBox, preserveAR, crop, anamorph)**

This is an operation that fulfills a common need: that of changing the size of an image prior to saving. The arguments are self-explanatory: letter- or window-boxing is automatically performed if aspect ratio is to be preserved and cropping is not enabled. The *anamorph* argument is unity when no anamorphic display is intended: larger than unity when it is.

This is not a "native" operation: it internally comprises other operations arranged to yield the result desired.

### Parameters

*newBox*

Desired box (list).

*preserveAR*

Should the aspect ratio be preserved (bool)? default = true.

*crop*

Should the image be cropped to preserve aspect ratio (bool)? default = true.

*anamorph*

If the final image is destined for anamorphic display, the "stretch factor" (float). default = 1.0.

**ice.Image Flip(***x, y, transpose***)**

This operation is optimized to perform the eight possible "unity-scale" transformations. These are illustrated below.

### Parameters

*x*

Flip in x (bool)

*y*

Flip in y (bool)

t*ranspose:*

Transpose the image (bool)

### Example

# No-op result = m1_1.Flip(False, False, False)

# Transpose axes result = m1_1.Flip(False, False, True)

# Flip in Y result = m1_1.Flip(False, True, False)

# Flip in Y and transpose axes result = m1_1.Flip(False, True, True)

# Flip in X result = m1_1.Flip(True, False, False)

# Flip in X and transpose axes result = m1_1.Flip(True, False, True)

# Flip in X and Y result = m1_1.Flip(True, True, False)

# Flip in X and Y and transpose result = m1_1.Flip(True, True, True)

**ice.Image DisplacementWarp(***warpImg, minMax, filterType, filterScale***)**

General displacement warp operation. *WarpImg* is a two-channel vector field containing the offset of the source pixel for each result pixel. The actual offset is given by:

O' = o * (max − min) + min

The type of the filter is normally best set to FILTER_CATROM. Since it is not possible to analytically determine a single best filter width, *filterScale* should be chosen to yield the best possible combination of sharpness and anti-aliasing. 1.0 is a good place to start: smaller values yield wider filters (and less sharpness).

### Parameters

*warpImg*

Displacement image (ice.Image)

*minMax*

Displacements corresponding to 0 and 1 (list). defaults to [0, 1].

*filterType*

Filter type. Defaults to CatmullRom.

*filterScale*

Scale equivalent for filter width (float) defaults to 1.0

### Example

*Original Image:*

*Displacement Image:*

*Warped/Resultant Image:*

minMax = [0, 10] filter = ice.constants.FILTER_MITCHELL_NETRAVALI fScale = 1.0 result = fruit.DisplacementWarp(disp, minMax, filter, fScale)