1/*
2 * Copyright (C) 2013 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
17package android.support.rastermill;
18
19import android.graphics.Bitmap;
20import java.nio.ByteBuffer;
21
22import java.io.InputStream;
23
24public class FrameSequence {
25    static {
26        System.loadLibrary("framesequence");
27    }
28
29    private final long mNativeFrameSequence;
30    private final int mWidth;
31    private final int mHeight;
32    private final boolean mOpaque;
33    private final int mFrameCount;
34    private final int mDefaultLoopCount;
35
36    public int getWidth() { return mWidth; }
37    public int getHeight() { return mHeight; }
38    public boolean isOpaque() { return mOpaque; }
39    public int getFrameCount() { return mFrameCount; }
40    public int getDefaultLoopCount() { return mDefaultLoopCount; }
41
42    private static native FrameSequence nativeDecodeByteArray(byte[] data, int offset, int length);
43    private static native FrameSequence nativeDecodeStream(InputStream is, byte[] tempStorage);
44    private static native FrameSequence nativeDecodeByteBuffer(ByteBuffer buffer, int offset, int capacity);
45    private static native void nativeDestroyFrameSequence(long nativeFrameSequence);
46    private static native long nativeCreateState(long nativeFrameSequence);
47    private static native void nativeDestroyState(long nativeState);
48    private static native long nativeGetFrame(long nativeState, int frameNr,
49            Bitmap output, int previousFrameNr);
50
51    @SuppressWarnings("unused") // called by native
52    private FrameSequence(long nativeFrameSequence, int width, int height,
53                          boolean opaque, int frameCount, int defaultLoopCount) {
54        mNativeFrameSequence = nativeFrameSequence;
55        mWidth = width;
56        mHeight = height;
57        mOpaque = opaque;
58        mFrameCount = frameCount;
59        mDefaultLoopCount = defaultLoopCount;
60    }
61
62    public static FrameSequence decodeByteArray(byte[] data) {
63        return decodeByteArray(data, 0, data.length);
64    }
65
66    public static FrameSequence decodeByteArray(byte[] data, int offset, int length) {
67        if (data == null) throw new IllegalArgumentException();
68        if (offset < 0 || length < 0 || (offset + length > data.length)) {
69            throw new IllegalArgumentException("invalid offset/length parameters");
70        }
71        return nativeDecodeByteArray(data, offset, length);
72    }
73
74    public static FrameSequence decodeByteBuffer(ByteBuffer buffer) {
75        if (buffer == null) throw new IllegalArgumentException();
76        if (!buffer.isDirect()) {
77            if (buffer.hasArray()) {
78                byte[] byteArray = buffer.array();
79                return decodeByteArray(byteArray, buffer.position(), buffer.remaining());
80            } else {
81                throw new IllegalArgumentException("Cannot have non-direct ByteBuffer with no byte array");
82            }
83        }
84        return nativeDecodeByteBuffer(buffer, buffer.position(), buffer.remaining());
85    }
86
87    public static FrameSequence decodeStream(InputStream stream) {
88        if (stream == null) throw new IllegalArgumentException();
89        byte[] tempStorage = new byte[16 * 1024]; // TODO: use buffer pool
90        return nativeDecodeStream(stream, tempStorage);
91    }
92
93    State createState() {
94        if (mNativeFrameSequence == 0) {
95            throw new IllegalStateException("attempted to use incorrectly built FrameSequence");
96        }
97
98        long nativeState = nativeCreateState(mNativeFrameSequence);
99        if (nativeState == 0) {
100            return null;
101        }
102        return new State(nativeState);
103    }
104
105    @Override
106    protected void finalize() throws Throwable {
107        try {
108            if (mNativeFrameSequence != 0) nativeDestroyFrameSequence(mNativeFrameSequence);
109        } finally {
110            super.finalize();
111        }
112    }
113
114    /**
115     * Playback state used when moving frames forward in a frame sequence.
116     *
117     * Note that this doesn't require contiguous frames to be rendered, it just stores
118     * information (in the case of gif, a recall buffer) that will be used to construct
119     * frames based upon data recorded before previousFrameNr.
120     *
121     * Note: {@link #destroy()} *must* be called before the object is GC'd to free native resources
122     *
123     * Note: State holds a native ref to its FrameSequence instance, so its FrameSequence should
124     * remain ref'd while it is in use
125     */
126    static class State {
127        private long mNativeState;
128
129        public State(long nativeState) {
130            mNativeState = nativeState;
131        }
132
133        public void destroy() {
134            if (mNativeState != 0) {
135                nativeDestroyState(mNativeState);
136                mNativeState = 0;
137            }
138        }
139
140        // TODO: consider adding alternate API for drawing into a SurfaceTexture
141        public long getFrame(int frameNr, Bitmap output, int previousFrameNr) {
142            if (output == null || output.getConfig() != Bitmap.Config.ARGB_8888) {
143                throw new IllegalArgumentException("Bitmap passed must be non-null and ARGB_8888");
144            }
145            if (mNativeState == 0) {
146                throw new IllegalStateException("attempted to draw destroyed FrameSequenceState");
147            }
148            return nativeGetFrame(mNativeState, frameNr, output, previousFrameNr);
149        }
150    }
151}
152