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
18package android.filterpacks.base;
19
20import android.filterfw.core.Filter;
21import android.filterfw.core.FilterContext;
22import android.filterfw.core.Frame;
23import android.filterfw.core.FrameFormat;
24import android.filterfw.core.GenerateFieldPort;
25import android.filterfw.core.GenerateFinalPort;
26import android.filterfw.core.KeyValueMap;
27import android.filterfw.core.NativeProgram;
28import android.filterfw.core.NativeFrame;
29import android.filterfw.core.Program;
30import android.os.Handler;
31import android.os.Looper;
32
33import java.lang.Runnable;
34
35/**
36 * @hide
37 */
38public class CallbackFilter extends Filter {
39
40    @GenerateFieldPort(name = "listener", hasDefault = true)
41    private FilterContext.OnFrameReceivedListener mListener;
42
43    @GenerateFieldPort(name = "userData", hasDefault = true)
44    private Object mUserData;
45
46    @GenerateFinalPort(name = "callUiThread", hasDefault = true)
47    private boolean mCallbacksOnUiThread = true;
48
49    private Handler mUiThreadHandler;
50
51    private class CallbackRunnable implements Runnable {
52        private Filter mFilter;
53        private Frame mFrame;
54        private Object mUserData;
55        private FilterContext.OnFrameReceivedListener mListener;
56
57        public CallbackRunnable(FilterContext.OnFrameReceivedListener listener, Filter filter, Frame frame, Object userData) {
58            mListener = listener;
59            mFilter = filter;
60            mFrame = frame;
61            mUserData = userData;
62        }
63
64        public void run() {
65            mListener.onFrameReceived(mFilter, mFrame, mUserData);
66            mFrame.release();
67        }
68    }
69
70    public CallbackFilter(String name) {
71        super(name);
72    }
73
74    @Override
75    public void setupPorts() {
76        addInputPort("frame");
77    }
78
79    public void prepare(FilterContext context) {
80        if (mCallbacksOnUiThread) {
81            mUiThreadHandler = new Handler(Looper.getMainLooper());
82        }
83    }
84
85    public void process(FilterContext context) {
86        // Get frame and forward to listener
87        final Frame input = pullInput("frame");
88        if (mListener != null) {
89            if (mCallbacksOnUiThread) {
90                input.retain();
91                CallbackRunnable uiRunnable = new CallbackRunnable(mListener, this, input, mUserData);
92                if (!mUiThreadHandler.post(uiRunnable)) {
93                    throw new RuntimeException("Unable to send callback to UI thread!");
94                }
95            } else {
96                mListener.onFrameReceived(this, input, mUserData);
97            }
98        } else {
99            throw new RuntimeException("CallbackFilter received frame, but no listener set!");
100        }
101    }
102
103}
104