1 /* 2 * Copyright (C) 2011 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17 18 package android.filterfw; 19 20 import android.filterfw.core.Filter; 21 import android.filterfw.core.FilterFactory; 22 import android.filterfw.core.FilterFunction; 23 import android.filterfw.core.Frame; 24 import android.filterfw.core.FrameManager; 25 26 /** 27 * A FilterFunctionEnvironment provides a simple functional front-end to manually executing 28 * filters. Use this environment if a graph-based approach is not convenient for your case. 29 * Typically, a FilterFunctionEnvironment is used as follows: 30 * 1. Instantiate a new FilterFunctionEnvironment instance. 31 * 2. Perform any configuration, such as setting a GL environment. 32 * 3. Wrap Filters into FilterFunctions by calling createFunction(). 33 * 4. Execute FilterFunctions individually and use the results for further processing. 34 * Additionally, there is a convenience method to execute a number of filters in sequence. 35 * @hide 36 */ 37 public class FilterFunctionEnvironment extends MffEnvironment { 38 39 /** 40 * Create a new FilterFunctionEnvironment with the default components. 41 */ 42 public FilterFunctionEnvironment() { 43 super(null); 44 } 45 46 /** 47 * Create a new FilterFunctionEnvironment with a custom FrameManager. Pass null to auto-create 48 * a FrameManager. 49 * 50 * @param frameManager The FrameManager to use, or null to auto-create one. 51 */ 52 public FilterFunctionEnvironment(FrameManager frameManager) { 53 super(frameManager); 54 } 55 56 /** 57 * Create a new FilterFunction from a specific filter class. The function is initialized with 58 * the given key-value list of parameters. Note, that this function uses the default shared 59 * FilterFactory to create the filter instance. 60 * 61 * @param filterClass The class of the filter to wrap. This must be a Filter subclass. 62 * @param parameters An argument list of alternating key-value filter parameters. 63 * @return A new FilterFunction instance. 64 */ 65 public FilterFunction createFunction(Class filterClass, Object... parameters) { 66 String filterName = "FilterFunction(" + filterClass.getSimpleName() + ")"; 67 Filter filter = FilterFactory.sharedFactory().createFilterByClass(filterClass, filterName); 68 filter.initWithAssignmentList(parameters); 69 return new FilterFunction(getContext(), filter); 70 } 71 72 /** 73 * Convenience method to execute a sequence of filter functions. Note that every function in 74 * the list MUST have one input and one output port, except the first filter (which must not 75 * have any input ports) and the last filter (which may not have any output ports). 76 * 77 * @param functions A list of filter functions. The first filter must be a source filter. 78 * @return The result of the last filter executed, or null if the last filter did not 79 produce any output. 80 * 81 public Frame executeSequence(FilterFunction[] functions) { 82 Frame oldFrame = null; 83 Frame newFrame = null; 84 for (FilterFunction filterFunction : functions) { 85 if (oldFrame == null) { 86 newFrame = filterFunction.executeWithArgList(); 87 } else { 88 newFrame = filterFunction.executeWithArgList(oldFrame); 89 oldFrame.release(); 90 } 91 oldFrame = newFrame; 92 } 93 if (oldFrame != null) { 94 oldFrame.release(); 95 } 96 return newFrame; 97 }*/ 98 99 } 100
