在android中进行视频的分割

最近项目有个需求要对录制的视频进行分割，查了很多资料，看到ffmpeg可以对视频进行分割。上网找到别人基于android的开源ffmpeg，终于编译成功ffmpeg.so。但是要使用的话还要查ffmpeg的api，并且写jni的调用接口，非常麻烦。偶然情况下发现了开源软件mp4parser: http://code.google.com/p/mp4parser/ 一款非常棒的开源软件，可以对视频进行分割、组合等操作，而且使用起来非常简单。通过svn对其下载后可以看到里面带着视频分割的例子，但是是用java实现，将其稍微修改一下就可以用在Android上了。

首先将例子中的代码修改为一个工具类，通过接口传进视频文件的路径和截取视频的开始、结束时间。需要注意的是，如果传的开始时间是10s，视频一般不会刚好是从10s开始的，要根据视频的关键帧做一下调整。截取出来的视频会放到存储卡的Clip目录下。代码如下：

点击(此处)折叠或打开

1. package com.example.mp4clip;
2. import java.io.File;
3. import java.io.FileOutputStream;
4. import java.io.IOException;
5. import java.nio.channels.FileChannel;
6. import java.util.Arrays;
7. import java.util.LinkedList;
8. import java.util.List;
9. import android.os.Environment;
10. import android.util.Log;
11. import com.coremedia.iso.boxes.Container;
12. import com.googlecode.mp4parser.authoring.Movie;
13. import com.googlecode.mp4parser.authoring.Track;
14. import com.googlecode.mp4parser.authoring.builder.DefaultMp4Builder;
15. import com.googlecode.mp4parser.authoring.container.mp4.MovieCreator;
16. import com.googlecode.mp4parser.authoring.tracks.CroppedTrack;
17. public class ClipUtil {
18. private static final String TAG = "ClipUtil";
19. /**
20. * 截取指定时间段的视频
21. * @param path 视频的路径
22. * @param begin 需要截取的开始时间
23. * @param end 截取的结束时间
24. * @throws IOException
25. */
26. public static void clipVideo(String path, double begin, double end)
27. throws IOException {
28. File mSdCardDir = Environment.getExternalStorageDirectory();
29. File f = new File(mSdCardDir.getAbsolutePath() + File.separator
30. + Util.SAVE_PATH);
31. if (!f.exists()) {
32. f.mkdir();
33. }
34. // Movie movie = new MovieCreator().build(new
35. // RandomAccessFile("/home/sannies/suckerpunch-distantplanet_h1080p/suckerpunch-distantplanet_h1080p.mov",
36. // "r").getChannel());
37. Movie movie = MovieCreator.build(path);
38. List<Track> tracks = movie.getTracks();
39. movie.setTracks(new LinkedList<Track>());
40. // remove all tracks we will create new tracks from the old
41. double startTime1 = begin;
42. double endTime1 = end;
43. // double startTime2 = 30;
44. // double endTime2 = 40;
45. boolean timeCorrected = false;
46. // Here we try to find a track that has sync samples. Since we can only
47. // start decoding
48. // at such a sample we SHOULD make sure that the start of the new
49. // fragment is exactly
50. // such a frame
51. for (Track track : tracks) {
52. if (track.getSyncSamples() != null
53. && track.getSyncSamples().length > 0) {
54. if (timeCorrected) {
55. // This exception here could be a false positive in case we
56. // have multiple tracks
57. // with sync samples at exactly the same positions. E.g. a
58. // single movie containing
59. // multiple qualities of the same video (Microsoft Smooth
60. // Streaming file)
61. Log.e(TAG,
62. "The startTime has already been corrected by another track with SyncSample. Not Supported.");
63. throw new RuntimeException(
64. "The startTime has already been corrected by another track with SyncSample. Not Supported.");
65. }
66. startTime1 = correctTimeToSyncSample(track, startTime1, false);
67. endTime1 = correctTimeToSyncSample(track, endTime1, true);
68. // startTime2 = correctTimeToSyncSample(track, startTime2,
69. // false);
70. // endTime2 = correctTimeToSyncSample(track, endTime2, true);
71. timeCorrected = true;
72. }
73. }
74. for (Track track : tracks) {
75. long currentSample = 0;
76. double currentTime = 0;
77. double lastTime = 0;
78. long startSample1 = -1;
79. long endSample1 = -1;
80. // long startSample2 = -1;
81. // long endSample2 = -1;
82. for (int i = 0; i < track.getSampleDurations().length; i++) {
83. long delta = track.getSampleDurations()[i];
84. if (currentTime > lastTime && currentTime <= startTime1) {
85. // current sample is still before the new starttime
86. startSample1 = currentSample;
87. }
88. if (currentTime > lastTime && currentTime <= endTime1) {
89. // current sample is after the new start time and still
90. // before the new endtime
91. endSample1 = currentSample;
92. }
93. // if (currentTime > lastTime && currentTime <= startTime2) {
94. // // current sample is still before the new starttime
95. // startSample2 = currentSample;
96. // }
97. // if (currentTime > lastTime && currentTime <= endTime2) {
98. // // current sample is after the new start time and still
99. // before the new endtime
100. // endSample2 = currentSample;
101. // }
102. lastTime = currentTime;
103. currentTime += (double) delta
104. / (double) track.getTrackMetaData().getTimescale();
105. currentSample++;
106. }
107. movie.addTrack(new CroppedTrack(track, startSample1, endSample1));// new
108. // AppendTrack(new
109. // CroppedTrack(track,
110. // startSample1,
111. // endSample1),
112. // new
113. // CroppedTrack(track,
114. // startSample2,
115. // endSample2)));
116. }
117. long start1 = System.currentTimeMillis();
118. Container out = new DefaultMp4Builder().build(movie);
119. long start2 = System.currentTimeMillis();
120. FileOutputStream fos = new FileOutputStream(f.getAbsolutePath()
121. + File.separator
122. + String.format("output-%f-%f.mp4", startTime1, endTime1));
123. FileChannel fc = fos.getChannel();
124. out.writeContainer(fc);
125. fc.close();
126. fos.close();
127. long start3 = System.currentTimeMillis();
128. Log.e(TAG, "Building IsoFile took : " + (start2 - start1) + "ms");
129. Log.e(TAG, "Writing IsoFile took : " + (start3 - start2) + "ms");
130. Log.e(TAG,
131. "Writing IsoFile speed : "
132. + (new File(String.format("output-%f-%f.mp4",
133. startTime1, endTime1)).length()
134. / (start3 - start2) / 1000) + "MB/s");
135. }
136. private static double correctTimeToSyncSample(Track track, double cutHere,
137. boolean next) {
138. double[] timeOfSyncSamples = new double[track.getSyncSamples().length];
139. long currentSample = 0;
140. double currentTime = 0;
141. for (int i = 0; i < track.getSampleDurations().length; i++) {
142. long delta = track.getSampleDurations()[i];
143. if (Arrays.binarySearch(track.getSyncSamples(), currentSample + 1) >= 0) {
144. // samples always start with 1 but we start with zero therefore
145. // +1
146. timeOfSyncSamples[Arrays.binarySearch(track.getSyncSamples(),
147. currentSample + 1)] = currentTime;
148. }
149. currentTime += (double) delta
150. / (double) track.getTrackMetaData().getTimescale();
151. currentSample++;
152. }
153. double previous = 0;
154. for (double timeOfSyncSample : timeOfSyncSamples) {
155. if (timeOfSyncSample > cutHere) {
156. if (next) {
157. return timeOfSyncSample;
158. } else {
159. return previous;
160. }
161. }
162. previous = timeOfSyncSample;
163. }
164. return timeOfSyncSamples[timeOfSyncSamples.length - 1];
165. }
166. }

有了工具类，下面就是增加一个操作界面了。我用一个列表列出所有的视频，点击视频后就会在后台截取出5s~15s总共10s的视频。当然也可以根据需要加上自己想要的开始结束时间，代码如下：

点击(此处)折叠或打开

1. package com.example.mp4clip;
2. import java.io.IOException;
3. import java.lang.ref.SoftReference;
4. import android.app.Activity;
5. import android.content.Context;
6. import android.content.Intent;
7. import android.database.Cursor;
8. import android.graphics.drawable.Drawable;
9. import android.net.Uri;
10. import android.os.Bundle;
11. import android.os.Environment;
12. import android.provider.MediaStore;
13. import android.util.Log;
14. import android.util.SparseArray;
15. import android.view.Menu;
16. import android.view.MenuItem;
17. import android.view.View;
18. import android.view.ViewGroup;
19. import android.widget.AdapterView;
20. import android.widget.AdapterView.OnItemClickListener;
21. import android.widget.ImageView;
22. import android.widget.ListView;
23. import android.widget.SimpleCursorAdapter;
24. import android.widget.TextView;
25. import edu.mit.mobile.android.imagecache.ImageCache;
26. import edu.mit.mobile.android.imagecache.ImageCache.OnImageLoadListener;
27. public class MainActivity extends Activity implements OnItemClickListener,
28. OnImageLoadListener {
29. private static final String TAG = "MainActivity";
30. ListView mList;
31. private Cursor mCursor;
32. private final SparseArray<SoftReference<ImageView>> mImageViewsToLoad = new SparseArray<SoftReference<ImageView>>();
33. private ImageCache mCache;
34. @Override
35. protected void onCreate(Bundle savedInstanceState) {
36. super.onCreate(savedInstanceState);
37. setContentView(R.layout.activity_main);
38. mCache = ImageCache.getInstance(this);
39. mCache.registerOnImageLoadListener(this);
40. mList = (ListView) findViewById(R.id.list);
41. mList.setOnItemClickListener(this);
42. mCursor = getContentResolver().query(
43. MediaStore.Video.Media.EXTERNAL_CONTENT_URI, null, null, null,
44. MediaStore.Video.Media.DATE_MODIFIED + " desc");
45. SimpleCursorAdapter adapter = new videoListAdapter(this,
46. R.layout.video_listitem, mCursor,
47. new String[] { MediaStore.Video.Media.TITLE },
48. new int[] { R.id.video_title });
49. mList.setAdapter(adapter);
50. }
51. @Override
52. public boolean onCreateOptionsMenu(Menu menu) {
53. getMenuInflater().inflate(R.menu.main, menu);
54. return true;
55. }
56. public boolean onOptionsItemSelected(MenuItem item) {
57. // 扫描新多媒体文件,添加到数据库中
58. sendBroadcast(new Intent(Intent.ACTION_MEDIA_MOUNTED,
59. Uri.parse("file://"
60. + Environment.getExternalStorageDirectory()
61. .getAbsolutePath())));
62. return false;
63. }
64. @Override
65. public void onItemClick(AdapterView<?> parent, View view, int position,
66. long id) {
67. if (mCursor.moveToPosition(position)) {
68. int index = -1;
69. index = mCursor.getColumnIndex(MediaStore.Video.Media.DATA);
70. String path = null;
71. if (index >= 0) {
72. path = mCursor.getString(index);
73. try {
74. ClipUtil.clipVideo(path, 5, 15);
75. } catch (IOException e) {
76. // TODO Auto-generated catch block
77. e.printStackTrace();
78. }
79. }
80. }
81. }
82. private static final class ViewHolder {
83. /** 视频名称 */
84. TextView titleView;
85. /** 视频时长 */
86. TextView durationView;
87. /** 文件大小 */
88. TextView sizeView;
89. }
90. private class videoListAdapter extends SimpleCursorAdapter {
91. /*
92. * constructor.
93. */
94. public videoListAdapter(Context context, int layout, Cursor c,
95. String[] from, int[] to) {
96. super(context, layout, c, from, to);
97. }
98. @Override
99. public int getCount() {
100. return super.getCount();
101. }
102. @Override
103. public Object getItem(int position) {
104. return super.getItem(position);
105. }
106. @Override
107. public long getItemId(int position) {
108. return super.getItemId(position);
109. }
110. @Override
111. public View getView(int position, View convertView, ViewGroup parent) {
112. View view = super.getView(position, convertView, parent);
113. Cursor cursor = getCursor();
114. cursor.moveToPosition(position);
115. ViewHolder holder = (ViewHolder) view.getTag();
116. if (holder == null) {
117. holder = new ViewHolder();
118. holder.titleView = (TextView) view
119. .findViewById(R.id.video_title);
120. holder.durationView = (TextView) view
121. .findViewById(R.id.video_duration);
122. holder.sizeView = (TextView) view.findViewById(R.id.video_size);
123. }
124. view.setTag(holder);
125. final ImageView iv = (ImageView) view.findViewById(R.id.thumbnail);
126. int index = -1;
127. index = mCursor.getColumnIndex(MediaStore.Video.Media.DATA);
128. String path = null;
129. if (index >= 0) {
130. path = mCursor.getString(index);
131. try {
132. Drawable draw = mCache.loadImage(position, Uri.parse(path),
133. 120, 120);
134. if (draw != null) {
135. iv.setBackground(draw);
136. } else {
137. mImageViewsToLoad.put(position,
138. new SoftReference<ImageView>(iv));
139. }
140. } catch (IOException e) {
141. e.printStackTrace();
142. }
143. }
144. index = -1;
145. index = cursor.getColumnIndex(MediaStore.Video.Media.TITLE);
146. String title = null;
147. if (index >= 0) {
148. title = cursor.getString(index);
149. holder.titleView.setText(title);
150. }
151. index = -1;
152. index = cursor.getColumnIndex(MediaStore.Video.Media.DURATION);
153. int duration;
154. if (index >= 0) {
155. duration = cursor.getInt(index);
156. holder.durationView.setText(Util.durationFormat(duration));
157. }
158. index = -1;
159. index = cursor.getColumnIndex(MediaStore.Video.Media.SIZE);
160. long size;
161. if (index >= 0) {
162. size = cursor.getLong(index);
163. holder.sizeView.setText(Util.sizeFormat(size));
164. }
165. return view;
166. }
167. }
168. @Override
169. public void onImageLoaded(int id, Uri imageUri, Drawable image) {
170. Log.d(TAG, "onImageLoaded:" + id);
171. final SoftReference<ImageView> ivRef = mImageViewsToLoad.get(id);
172. if (ivRef == null) {
173. Log.d(TAG, "ivRef=null");
174. return;
175. }
176. final ImageView iv = ivRef.get();
177. if (iv == null) {
178. Log.d(TAG, "ivRef=null");
179. mImageViewsToLoad.remove(id);
180. return;
181. }
182. iv.setBackground(image);
183. }
184. }