001 /* 002 * 003 004 Licensed under the Apache License, Version 2.0 (the "License"); 005 you may not use this file except in compliance with the License. 006 You may obtain a copy of the License at 007 008 http://www.apache.org/licenses/LICENSE-2.0 009 010 Unless required by applicable law or agreed to in writing, software 011 distributed under the License is distributed on an "AS IS" BASIS, 012 WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 013 See the License for the specific language governing permissions and 014 limitations under the License. 015 */ 016 017 package railo.runtime.img.filter;import java.awt.image.BufferedImage; 018 019 import railo.runtime.engine.ThreadLocalPageContext; 020 import railo.runtime.exp.FunctionException; 021 import railo.runtime.exp.PageException; 022 import railo.runtime.img.ImageUtil; 023 import railo.runtime.type.KeyImpl; 024 import railo.runtime.type.List; 025 import railo.runtime.type.Struct; 026 027 028 029 /** 030 * A filter which simply multiplies pixel values by a given scale factor. 031 */ 032 public class RescaleFilter extends TransferFilter implements DynFiltering { 033 034 private float scale = 1.0f; 035 036 public RescaleFilter() { 037 } 038 039 public RescaleFilter(float scale) { 040 this.scale = scale; 041 } 042 043 protected float transferFunction( float v ) { 044 return v * scale; 045 } 046 047 /** 048 * Specifies the scale factor. 049 * @param scale the scale factor. 050 * @min-value 1 051 * @max-value 5+ 052 * @see #getScale 053 */ 054 public void setScale(float scale) { 055 this.scale = scale; 056 initialized = false; 057 } 058 059 /** 060 * Returns the scale factor. 061 * @return the scale factor. 062 * @see #setScale 063 */ 064 public float getScale() { 065 return scale; 066 } 067 068 public String toString() { 069 return "Colors/Rescale..."; 070 } 071 072 public BufferedImage filter(BufferedImage src, Struct parameters) throws PageException {BufferedImage dst=ImageUtil.createBufferedImage(src); 073 Object o; 074 if((o=parameters.removeEL(KeyImpl.init("Scale")))!=null)setScale(ImageFilterUtil.toFloatValue(o,"Scale")); 075 if((o=parameters.removeEL(KeyImpl.init("Dimensions")))!=null){ 076 int[] dim=ImageFilterUtil.toDimensions(o,"Dimensions"); 077 setDimensions(dim[0],dim[1]); 078 } 079 080 // check for arguments not supported 081 if(parameters.size()>0) { 082 throw new FunctionException(ThreadLocalPageContext.get(), "ImageFilter", 3, "parameters", "the parameter"+(parameters.size()>1?"s":"")+" ["+List.arrayToList(parameters.keysAsString(),", ")+"] "+(parameters.size()>1?"are":"is")+" not allowed, only the following parameters are supported [Scale, Dimensions]"); 083 } 084 085 return filter(src, dst); 086 } 087 } 088