我想在Android上合并mp4和mp3,我正在使用JavaCV,请先检查下面的代码,然后我解释了以下奇怪的错误:
private void test2() throws Exception {
String path = Environment.getExternalStorageDirectory()
.getAbsolutePath();
int testId = 4;
String videoPath = path + "/" + "sample" + testId + ".mp4";
String audioPath = path + "/" + "love.mp3";
String outputPath = path + "/" + "out" + testId + ".mp4";
FrameGrabber grabber1 = new FFmpegFrameGrabber(videoPath);
FrameGrabber grabber2 = new FFmpegFrameGrabber(audioPath);
grabber1.start();
grabber2.start();
FrameRecorder recorder = new FFmpegFrameRecorder(outputPath,
grabber1.getImageWidth(), grabber1.getImageHeight(),
grabber2.getAudioChannels());
double frameRate = grabber1.getFrameRate();
recorder.setFrameRate(frameRate);
recorder.setSampleRate(grabber2.getSampleRate());
recorder.setVideoQuality(1);
recorder.start();
Frame frame1, frame2 = null;
// getLengthInTime is correct, but getLengthInFrames not accurate.
Log.d(TAG, " Video lengthInTime:" + grabber1.getLengthInTime()
+ " Video frames:" + grabber1.getLengthInFrames());
// Record video.
int count = 0;
while (true) {
frame1 = grabber1.grabFrame();
if (frame1 == null) {
break;
}
frame1.samples = null;
recorder.record(frame1);
count++;
Log.d(TAG, "Video frame timestamp:" + grabber1.getTimestamp());
}
Log.d(TAG, " Video frame count:" + count);
// Record audtio.
long videoTimestamp = recorder.getTimestamp();
while (true) {
frame2 = grabber2.grabFrame();
if (frame2 != null && grabber2.getTimestamp() <= videoTimestamp) {
frame2.image = null;
recorder.record(frame2);
// Log.d(TAG, "Audio frame timestamp:" +
// grabber2.getTimestamp());
} else {
break;
}
}
// release
recorder.stop();
recorder.release();
grabber1.stop();
grabber2.stop();
}
输出的音频没问题,但视频被扼杀了。视频播放1s并停止1s,然后像这样重复播放。我通过手机摄像头录制的输入视频。
我试着计算视频帧的实际数量,我发现实数远远大于方法getLengthInFrames()得到的数字。
答案 0 :(得分:1)
frameGrabber抓取ImageFrames和Sound Frames
如果您需要处理VideoFrame或其计数,请执行此操作
Frame grabFrame = frameGrabber.grabFrame();
if (grabFrame == null) {
// all frames are processed
System.out.println("!!! Failed cvQueryFrame");
runOnUiThread(new Runnable() {
@Override
public void run() {
Toast.makeText(RecordActivity.this, "Done !!!", Toast.LENGTH_SHORT).show();
}
});
break;
}
if (grabFrame.image != null) {
//This is a video Frame, Do your work here
}
}