我来自一个线程 Encoding H.264 from camera with Android MediaCodec .我的设置非常相似。但是，我尝试使用 javacv 编写多路编码帧并通过 rtmp 广播它们。
RtmpClient.java
...
private volatile BlockingQueue<byte[]> mFrameQueue = new LinkedBlockingQueue<byte[]>(MAXIMUM_VIDEO_FRAME_BACKLOG);
...
private void startStream() throws FrameRecorder.Exception, IOException {
if (TextUtils.isEmpty(mDestination)) {
throw new IllegalStateException("Cannot start RtmpClient without destination");
}
if (mCamera == null) {
throw new IllegalStateException("Cannot start RtmpClient without camera.");
}
Camera.Parameters cameraParams = mCamera.getParameters();
mRecorder = new FFmpegFrameRecorder(
mDestination,
mVideoQuality.resX,
mVideoQuality.resY,
(mAudioQuality.channelType.equals(AudioQuality.CHANNEL_TYPE_STEREO) ? 2 : 1));
mRecorder.setFormat("flv");
mRecorder.setFrameRate(mVideoQuality.frameRate);
mRecorder.setVideoBitrate(mVideoQuality.bitRate);
mRecorder.setVideoCodec(avcodec.AV_CODEC_ID_H264);
mRecorder.setSampleRate(mAudioQuality.samplingRate);
mRecorder.setAudioBitrate(mAudioQuality.bitRate);
mRecorder.setAudioCodec(avcodec.AV_CODEC_ID_AAC);
mVideoStream = new VideoStream(mRecorder, mVideoQuality, mFrameQueue, mCamera);
mAudioStream = new AudioStream(mRecorder, mAudioQuality);
mRecorder.start();
// Setup a bufferred preview callback
setupCameraCallback(mCamera, mRtmpClient, DEFAULT_PREVIEW_CALLBACK_BUFFERS,
mVideoQuality.resX * mVideoQuality.resY * ImageFormat.getBitsPerPixel(
cameraParams.getPreviewFormat())/8);
try {
mVideoStream.start();
mAudioStream.start();
}
catch(Exception e) {
e.printStackTrace();
stopStream();
}
}
...
@Override
public void onPreviewFrame(byte[] data, Camera camera) {
boolean frameQueued = false;
if (mRecorder == null || data == null) {
return;
}
frameQueued = mFrameQueue.offer(data);
// return the buffer to be reused - done in videostream
//camera.addCallbackBuffer(data);
}
...
VideoStream.java
...
@Override
public void run() {
try {
mMediaCodec = MediaCodec.createEncoderByType("video/avc");
MediaFormat mediaFormat = MediaFormat.createVideoFormat("video/avc", mVideoQuality.resX, mVideoQuality.resY);
mediaFormat.setInteger(MediaFormat.KEY_BIT_RATE, mVideoQuality.bitRate);
mediaFormat.setInteger(MediaFormat.KEY_FRAME_RATE, mVideoQuality.frameRate);
mediaFormat.setInteger(MediaFormat.KEY_COLOR_FORMAT, MediaCodecInfo.CodecCapabilities.COLOR_FormatYUV420SemiPlanar);
mediaFormat.setInteger(MediaFormat.KEY_I_FRAME_INTERVAL, 1);
mMediaCodec.configure(mediaFormat, null, null, MediaCodec.CONFIGURE_FLAG_ENCODE);
mMediaCodec.start();
}
catch(IOException e) {
e.printStackTrace();
}
long startTimestamp = System.currentTimeMillis();
long frameTimestamp = 0;
byte[] rawFrame = null;
try {
while (!Thread.interrupted()) {
rawFrame = mFrameQueue.take();
frameTimestamp = 1000 * (System.currentTimeMillis() - startTimestamp);
encodeFrame(rawFrame, frameTimestamp);
// return the buffer to be reused
mCamera.addCallbackBuffer(rawFrame);
}
}
catch (InterruptedException ignore) {
// ignore interrup while waiting
}
// Clean up video stream allocations
try {
mMediaCodec.stop();
mMediaCodec.release();
mOutputStream.flush();
mOutputStream.close();
} catch (Exception e){
e.printStackTrace();
}
}
...
private void encodeFrame(byte[] input, long timestamp) {
try {
ByteBuffer[] inputBuffers = mMediaCodec.getInputBuffers();
ByteBuffer[] outputBuffers = mMediaCodec.getOutputBuffers();
int inputBufferIndex = mMediaCodec.dequeueInputBuffer(0);
if (inputBufferIndex >= 0) {
ByteBuffer inputBuffer = inputBuffers[inputBufferIndex];
inputBuffer.clear();
inputBuffer.put(input);
mMediaCodec.queueInputBuffer(inputBufferIndex, 0, input.length, timestamp, 0);
}
MediaCodec.BufferInfo bufferInfo = new MediaCodec.BufferInfo();
int outputBufferIndex = mMediaCodec.dequeueOutputBuffer(bufferInfo, 0);
if (outputBufferIndex >= 0) {
while (outputBufferIndex >= 0) {
ByteBuffer outputBuffer = outputBuffers[outputBufferIndex];
// Should this be a direct byte buffer?
byte[] outData = new byte[bufferInfo.size - bufferInfo.offset];
outputBuffer.get(outData);
mFrameRecorder.record(outData, bufferInfo.offset, outData.length, timestamp);
mMediaCodec.releaseOutputBuffer(outputBufferIndex, false);
outputBufferIndex = mMediaCodec.dequeueOutputBuffer(bufferInfo, 0);
}
}
else if (outputBufferIndex == MediaCodec.INFO_OUTPUT_BUFFERS_CHANGED) {
outputBuffers = mMediaCodec.getOutputBuffers();
} else if (outputBufferIndex == MediaCodec.INFO_OUTPUT_FORMAT_CHANGED) {
// ignore for now
}
} catch (Throwable t) {
t.printStackTrace();
}
}
...
FFmpegFrameRecorder.java
...
// Hackish codec copy frame recording function
public boolean record(byte[] encodedData, int offset, int length, long frameCount) throws Exception {
int ret;
if (encodedData == null) {
return false;
}
av_init_packet(video_pkt);
// this is why i wondered whether I should get outputbuffer data into direct byte buffer
video_outbuf.put(encodedData, 0, encodedData.length);
video_pkt.data(video_outbuf);
video_pkt.size(video_outbuf_size);
video_pkt.pts(frameCount);
video_pkt.dts(frameCount);
video_pkt.stream_index(video_st.index());
synchronized (oc) {
/* write the compressed frame in the media file */
if (interleaved && audio_st != null) {
if ((ret = av_interleaved_write_frame(oc, video_pkt)) < 0) {
throw new Exception("av_interleaved_write_frame() error " + ret + " while writing interleaved video frame.");
}
} else {
if ((ret = av_write_frame(oc, video_pkt)) < 0) {
throw new Exception("av_write_frame() error " + ret + " while writing video frame.");
}
}
}
return (video_pkt.flags() & AV_PKT_FLAG_KEY) == 1;
}
...
当我尝试流式传输视频并对其运行 ffprobe 时，我得到以下输出:
ffprobe version 2.5.3 Copyright (c) 2007-2015 the FFmpeg developers
built on Jan 19 2015 12:56:57 with gcc 4.1.2 (GCC) 20080704 (Red Hat 4.1.2-55)
configuration: --prefix=/usr --bindir=/usr/bin --datadir=/usr/share/ffmpeg --incdir=/usr/include/ffmpeg --libdir=/usr/lib64 --mandir=/usr/share/man --arch=x86_64 --optflags='-O2 -g -pipe -Wall -Wp,-D_FORTIFY_SOURCE=2 -fexceptions -fstack-protector --param=ssp-buffer-size=4 -m64 -mtune=generic' --enable-bzlib --disable-crystalhd --enable-libass --enable-libdc1394 --enable-libfaac --enable-nonfree --disable-indev=jack --enable-libfreetype --enable-libgsm --enable-libmp3lame --enable-openal --enable-libopencv --enable-libopenjpeg --enable-libopus --enable-librtmp --enable-libtheora --enable-libvorbis --enable-libvpx --enable-libx264 --enable-libxvid --enable-x11grab --enable-avfilter --enable-avresample --enable-postproc --enable-pthreads --disable-static --enable-shared --enable-gpl --disable-debug --disable-stripping --enable-libcaca --shlibdir=/usr/lib64 --enable-runtime-cpudetect
libavutil 54. 15.100 / 54. 15.100
libavcodec 56. 13.100 / 56. 13.100
libavformat 56. 15.102 / 56. 15.102
libavdevice 56. 3.100 / 56. 3.100
libavfilter 5. 2.103 / 5. 2.103
libavresample 2. 1. 0 / 2. 1. 0
libswscale 3. 1.101 / 3. 1.101
libswresample 1. 1.100 / 1. 1.100
libpostproc 53. 3.100 / 53. 3.100
Metadata:
Server NGINX RTMP (github.com/arut/nginx-rtmp-module)
width 320.00
height 240.00
displayWidth 320.00
displayHeight 240.00
duration 0.00
framerate 0.00
fps 0.00
videodatarate 261.00
videocodecid 7.00
audiodatarate 62.00
audiocodecid 10.00
profile
level
[live_flv @ 0x1edb0820] Could not find codec parameters for stream 0 (Video: none, none, 267 kb/s): unknown codec
Consider increasing the value for the 'analyzeduration' and 'probesize' options
Input #0, live_flv, from 'rtmp://<server>/input/<stream id>':
Metadata:
Server : NGINX RTMP (github.com/arut/nginx-rtmp-module)
displayWidth : 320
displayHeight : 240
fps : 0
profile :
level :
Duration: 00:00:00.00, start: 16.768000, bitrate: N/A
Stream #0:0: Video: none, none, 267 kb/s, 1k tbr, 1k tbn, 1k tbc
Stream #0:1: Audio: aac (LC), 16000 Hz, mono, fltp, 63 kb/s
Unsupported codec with id 0 for input stream 0
无论如何，我都不是 H264 或视频编码方面的专家。我知道从 MediaCodec 出来的编码帧包含 SPS NAL、PPS NAL 和帧 NAL 单元。我还将 MediaCodec 输出写入一个文件并能够播放它(我确实必须指定格式和帧率，否则它会播放得太快)。
我的假设是事情应该有效(看看我知道的有多么少 :))。知道SPS和PPS都写出来了，decoder应该知道就够了。然而，ffprobe 无法识别编解码器、fps 和其他视频信息。我是否需要将数据包标志信息传递给 FFmpegFrameRecorder.java:record() 函数？还是应该使用直接缓冲区？任何建议将不胜感激!我应该通过提示来解决问题。
PS:我知道一些编解码器使用 Planar 和其他 SemiPlanar 颜色格式。如果我克服了这一点，这种区别将在稍后出现。另外，我没有采用 Surface 到 MediaCodec 的方式，因为我需要支持 API 17，它需要比这条路线更多的变化，我认为这有助于我理解更基本的流程。阿甘，我感谢任何建议。如果有什么需要澄清的，请告诉我。
更新#1
所以做了更多测试后，我看到我的编码器输出以下帧:
000000016742800DDA0507E806D0A1350000000168CE06E2
0000000165B840A6F1E7F0EA24000AE73BEB5F51CC7000233A84240...
0000000141E2031364E387FD4F9BB3D67F51CC7000279B9F9CFE811...
0000000141E40304423FFFFF0B7867F89FAFFFFFFFFFFCBE8EF25E6...
0000000141E602899A3512EF8AEAD1379F0650CC3F905131504F839...
...
第一帧包含 SPS 和 PPS。据我所见，这些只传输了一次。其余的是 NAL 类型 1 和 5。因此，我的假设是，要让 ffprobe 不仅在流开始时查看流信息，我还应该捕获 SPS 和 PPS 帧，并在一定数量的帧之后自己定期重新传输它们，或者可能在每个 I 帧之前。你怎么看？
更新#2
无法验证我是否正在成功写入帧。在尝试读回写入的数据包后，我无法验证写入的字节。奇怪的是，成功写入 IPL 图像和流后，我也无法在 avcodec_encode_video2 之后打印出编码数据包的字节。进入官方的死胡同。
最佳答案
据我所知，您不需要混合视频和音频流。当您发送 ANNOUNCE 消息时，您还指定了您将向哪些端口发送音频和视频流。您需要将它们单独打包并使用 RTP 发送。有关详细信息，请参阅维基百科。 https://en.wikipedia.org/wiki/Real_Time_Streaming_Protocol
关于android - 将 Android MediaCodec 编码的 H264 数据包复用到 RTMP 中，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/28775931/