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 com.android.gallery3d.jpegstream;
18
19import java.io.FilterOutputStream;
20import java.io.IOException;
21import java.io.OutputStream;
22public class JPEGOutputStream extends FilterOutputStream {
23    private long JNIPointer = 0; // Used by JNI code. Don't touch.
24
25    private byte[] mTmpBuffer = new byte[1];
26    private int mWidth = 0;
27    private int mHeight = 0;
28    private int mQuality = 0;
29    private int mFormat = -1;
30    private boolean mValidConfig = false;
31    private boolean mConfigChanged = false;
32
33    public JPEGOutputStream(OutputStream out) {
34        super(out);
35    }
36
37    public JPEGOutputStream(OutputStream out, int width, int height, int quality,
38            int format) {
39        super(out);
40        setConfig(width, height, quality, format);
41    }
42
43    public boolean setConfig(int width, int height, int quality, int format) {
44        // Clamp quality to range (0, 100]
45        quality = Math.max(Math.min(quality, 100), 1);
46
47        // Make sure format is valid
48        switch (format) {
49            case JpegConfig.FORMAT_GRAYSCALE:
50            case JpegConfig.FORMAT_RGB:
51            case JpegConfig.FORMAT_ABGR:
52            case JpegConfig.FORMAT_RGBA:
53                break;
54            default:
55                return false;
56        }
57
58        // If valid, set configuration
59        if (width > 0 && height > 0) {
60            mWidth = width;
61            mHeight = height;
62            mFormat = format;
63            mQuality = quality;
64            mValidConfig = true;
65            mConfigChanged = true;
66        } else {
67            return false;
68        }
69
70        return mValidConfig;
71    }
72
73    @Override
74    public void close() throws IOException {
75        cleanup();
76        super.close();
77    }
78
79    @Override
80    public void write(byte[] buffer, int offset, int length) throws IOException {
81        if (offset < 0 || length < 0 || (offset + length) > buffer.length) {
82            throw new ArrayIndexOutOfBoundsException(String.format(
83                    " buffer length %d, offset %d, length %d",
84                    buffer.length, offset, length));
85        }
86        if (!mValidConfig) {
87            return;
88        }
89        if (mConfigChanged) {
90            cleanup();
91            int flag = setup(out, mWidth, mHeight, mFormat, mQuality);
92            switch(flag) {
93                case JpegConfig.J_SUCCESS:
94                    break; // allow setup to continue
95                case JpegConfig.J_ERROR_BAD_ARGS:
96                    throw new IllegalArgumentException("Bad arguments to write");
97                default:
98                    throw new IOException("Error to writing jpeg headers.");
99            }
100            mConfigChanged = false;
101        }
102        int returnCode = JpegConfig.J_ERROR_FATAL;
103        try {
104            returnCode = writeInputBytes(buffer, offset, length);
105        } finally {
106            if (returnCode < 0) {
107                cleanup();
108            }
109        }
110        if (returnCode < 0) {
111            throw new IOException("Error writing jpeg stream");
112        }
113    }
114
115    @Override
116    public void write(byte[] buffer) throws IOException {
117        write(buffer, 0, buffer.length);
118    }
119
120    @Override
121    public void write(int oneByte) throws IOException {
122        mTmpBuffer[0] = (byte) oneByte;
123        write(mTmpBuffer);
124    }
125
126    @Override
127    protected void finalize() throws Throwable {
128        try {
129            cleanup();
130        } finally {
131            super.finalize();
132        }
133    }
134
135    native private int setup(OutputStream out, int width, int height, int format, int quality);
136
137    native private void cleanup();
138
139    native private int writeInputBytes(byte[] inBuffer, int offset, int inCount);
140
141    static {
142        System.loadLibrary("jni_jpegstream");
143    }
144}
145