/*
* Copyright (c) 2011-2016, Peter Abeles. All Rights Reserved.
*
* This file is part of BoofCV (http://boofcv.org).
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package boofcv.abst.distort;
import boofcv.alg.distort.ImageDistort;
import boofcv.alg.distort.PixelTransformAffine_F32;
import boofcv.alg.distort.PointToPixelTransform_F32;
import boofcv.alg.distort.impl.DistortSupport;
import boofcv.alg.interpolate.InterpolatePixel;
import boofcv.alg.interpolate.InterpolatePixelMB;
import boofcv.alg.interpolate.InterpolatePixelS;
import boofcv.alg.interpolate.InterpolationType;
import boofcv.core.image.border.BorderType;
import boofcv.core.image.border.FactoryImageBorder;
import boofcv.core.image.border.ImageBorder;
import boofcv.factory.distort.FactoryDistort;
import boofcv.factory.interpolate.FactoryInterpolation;
import boofcv.struct.distort.PixelTransform2_F32;
import boofcv.struct.distort.Point2Transform2_F32;
import boofcv.struct.image.ImageBase;
import boofcv.struct.image.ImageType;
import georegression.struct.affine.Affine2D_F32;
import georegression.struct.affine.Affine2D_F64;
/**
* <p>High level interface for rendering a distorted image into another one. Uses a flow style interface to remove
* much of the drugery.</p>
*
* <p>If you are changing the input images and avoiding declaring new memory then you need to be careful
* how this class is used. For example, call {@link #setRefs(ImageBase, ImageBase)} instead of
* {@link #init(ImageBase, ImageBase)}. Init() will discard the previous settings while with setRefs() it's possible
* to update only what has changed. Make sure you follow the instructions in setRefs() and browsing the code in this
* class might help you understand what's going on.</p>
*
* @author Peter Abeles
*/
public class FDistort
{
// type of input image
ImageType inputType;
// input and output images
ImageBase input,output;
// specifies how the borders are handled
ImageDistort distorter;
InterpolatePixel interp;
PixelTransform2_F32 outputToInput;
// type of border being used
BorderType borderType;
// if the transform should be cached or not.
boolean cached = false;
/**
* Constructor in which input and output images are specified. Equivalent to calling
* {@link #init(ImageBase, ImageBase)}
*
* @param input Input image
* @param output output image
*/
public FDistort(ImageBase input, ImageBase output) {
init(input, output);
}
/**
* Constructor
* @param inputType Type of input image
*/
public FDistort(ImageType inputType) {
this.inputType = inputType;
}
public FDistort() {
}
/**
* Specifies the input and output image and sets interpolation to BILINEAR, black image border, cache is off.
*/
public FDistort init(ImageBase input, ImageBase output) {
this.input = input;
this.output = output;
inputType = input.getImageType();
interp(InterpolationType.BILINEAR);
border(0);
cached = false;
distorter = null;
outputToInput = null;
return this;
}
/**
* All this does is set the references to the images. Nothing else is changed and its up to the
* user to correctly update everything else.
*
* If called the first time you need to do the following
* <pre>
* 1) specify the interpolation method
* 2) specify the transform
* 3) specify the border
* </pre>
*
* If called again and the image shape has changed you need to do the following:
* <pre>
* 1) Update the transform
* </pre>
*/
public FDistort setRefs( ImageBase input, ImageBase output ) {
this.input = input;
this.output = output;
inputType = input.getImageType();
return this;
}
/**
* Changes the input image. The previous distortion is thrown away only if the input
* image has a different shape
*/
public FDistort input( ImageBase input ) {
if( this.input == null || this.input.width != input.width || this.input.height != input.height ) {
distorter = null;
}
this.input = input;
inputType = input.getImageType();
return this;
}
/**
* Changes the output image. The previous distortion is thrown away only if the output
* image has a different shape
*/
public FDistort output( ImageBase output ) {
if( this.output == null || this.output.width != output.width || this.output.height != output.height ) {
distorter = null;
}
this.output = output;
return this;
}
/**
* Sets how the interpolation handles borders.
*/
public FDistort border( ImageBorder border ) {
interp.setBorder(border);
return this;
}
/**
* Sets the border by type.
*/
public FDistort border( BorderType type ) {
if( borderType == type )
return this;
borderType = type;
return border(FactoryImageBorder.generic(type, inputType));
}
/**
* Sets the border to a fixed gray-scale value
*/
public FDistort border( double value ) {
// to recycle here the value also needs to be saved
// if( borderType == BorderType.VALUE )
// return this;
borderType = BorderType.ZERO;
return border(FactoryImageBorder.genericValue(value, inputType));
}
/**
* <p>Sets the border to EXTEND.</p>
*/
public FDistort borderExt() {
return border(BorderType.EXTENDED);
}
/**
* used to provide a custom interpolation algorithm
*
* <p>
* NOTE: This will force the distorter to be declared again, even if nothing has changed. This only matters if
* you are being very careful about your memory management.
* </p>
*/
public FDistort interp(InterpolatePixelS interpolation) {
distorter = null;
this.interp = interpolation;
return this;
}
/**
* Specifies the interpolation used by type.
*/
public FDistort interp(InterpolationType type) {
distorter = null;
this.interp = FactoryInterpolation.createPixel(0, 255, type, BorderType.EXTENDED, inputType);
return this;
}
/**
* Sets interpolation to use nearest-neighbor
*/
public FDistort interpNN() {
return interp(InterpolationType.NEAREST_NEIGHBOR);
}
/**
* used to turn on and off caching of the distortion
*/
public FDistort cached( boolean cached ) {
distorter = null;
this.cached = cached;
return this;
}
/**
* Used to manually specify a transform. From output to input
*/
public FDistort transform( PixelTransform2_F32 outputToInput ) {
this.outputToInput = outputToInput;
return this;
}
/**
* Used to manually specify a transform. From output to input
*/
public FDistort transform( Point2Transform2_F32 outputToInput ) {
return transform( new PointToPixelTransform_F32(outputToInput));
}
/**
* Affine transform from input to output
*/
public FDistort affine(double a11, double a12, double a21, double a22,
double dx, double dy) {
PixelTransformAffine_F32 transform;
if( outputToInput != null && outputToInput instanceof PixelTransformAffine_F32 ) {
transform = (PixelTransformAffine_F32)outputToInput;
} else {
transform = new PixelTransformAffine_F32();
}
Affine2D_F32 m = new Affine2D_F32();
m.a11 = (float)a11;
m.a12 = (float)a12;
m.a21 = (float)a21;
m.a22 = (float)a22;
m.tx = (float)dx;
m.ty = (float)dy;
m.invert(transform.getModel());
return transform(transform);
}
public FDistort affine( Affine2D_F64 affine ) {
return affine(affine.a11,affine.a12,affine.a21,affine.a22,affine.tx,affine.ty);
}
/**
* <p>Applies a distortion which will rescale the input image into the output image. You
* might want to consider using {@link #scaleExt()} instead since it sets the border behavior
* to extended, which is probably what you want to do.</p>
*
* NOTE: Checks to see if it can recycle the previous transform and update it with a new affine model
* to avoid declaring new memory.
*/
public FDistort scale() {
if( outputToInput != null && outputToInput instanceof PixelTransformAffine_F32 ) {
PixelTransformAffine_F32 affine = (PixelTransformAffine_F32)outputToInput;
DistortSupport.transformScale(output, input, affine);
return this;
} else {
return transform(DistortSupport.transformScale(output, input, null));
}
}
/**
* Scales the image and sets the border to {@link BorderType#EXTENDED}. This is normally what you want
* to do when scaling an image. If you don't use an extended border when you hit the right and bottom
* boundaries it will go outside the image bounds and if a fixed value of 0 is used it will average towards
* zero.
*/
public FDistort scaleExt() {
return scale().borderExt();
}
/**
* Applies a distortion which will rotate the input image by the specified amount.
*/
public FDistort rotate( double angleInputToOutput ) {
PixelTransform2_F32 outputToInput = DistortSupport.transformRotate(input.width/2,input.height/2,
output.width/2,output.height/2,(float)angleInputToOutput);
return transform(outputToInput);
}
/**
* Applies the distortion.
*/
public void apply() {
// see if the distortion class needs to be created again
if( distorter == null ) {
Class typeOut = output.getImageType().getImageClass();
switch( input.getImageType().getFamily() ) {
case GRAY:
distorter = FactoryDistort.distortSB(cached, (InterpolatePixelS)interp, typeOut);
break;
case PLANAR:
distorter = FactoryDistort.distortPL(cached, (InterpolatePixelS)interp, typeOut);
break;
case INTERLEAVED:
distorter = FactoryDistort.distortIL(cached, (InterpolatePixelMB) interp, output.getImageType());
break;
default:
throw new IllegalArgumentException("Unsupported image type");
}
}
distorter.setModel(outputToInput);
distorter.apply(input,output);
}
}