public void writeHead() throws IOException {
if (null == streams) {
throw new IllegalArgumentException("No Streams Found");
}
ChannelBuffer buffer = ChannelBuffers.dynamicBuffer(1024);
int dataSize = 0;
// flv header
buffer.writeByte('F');
buffer.writeByte('L');
buffer.writeByte('V');
buffer.writeByte(0x01); // version
buffer.writeByte(0x05); // audio & video
buffer.writeInt(0x09); // header size
buffer.writeInt(0x00); // first tag size
// metadata
Map<String, Object> map = new LinkedHashMap<String, Object>();
map.put("duration", 0);
for (int i = 0; i < streams.length; i++) {
AVStream av = (AVStream) streams[i];
if (av.getFormat() instanceof VideoFormat) {
if (av.getWidth() > 0) {
map.put("width", av.getWidth());
}
if (av.getHeight() > 0) {
map.put("heigth", av.getHeight());
}
if (av.getFrameRate() > 0) {
map.put("videoframerate", av.getFrameRate());
}
} else if (av.getFormat() instanceof AudioFormat) {
if (av.getSampleRate() > 0) {
map.put("audiosamplerate", av.getSampleRate());
}
if (av.getNumChannels() > 0) {
map.put("audiochannels", av.getNumChannels());
}
}
}
ChannelBuffer onMetaData = ChannelBuffers.dynamicBuffer();
Amf0Value.encode(onMetaData, "onMetaData");
Amf0Value.encode(onMetaData, map);
dataSize = onMetaData.readableBytes();
buffer.writeByte(0x18); // script type
buffer.writeMedium(dataSize);
buffer.writeInt(0); // timestamp
buffer.writeMedium(0); // stream id
buffer.writeBytes(onMetaData);
buffer.writeInt(dataSize + 11); // pre tag size
buffer.readBytes(out, buffer.readableBytes());
// stream config(s)
for (AVStream stream : streams) {
tryWriteHeader(stream);
}
}
private void tryWriteHeader(AVStream stream) throws IOException {
if (stream.getStreamIndex() >= writeHeaders.length) {
logger.error("Fail Add Stream#{}", stream.getStreamIndex());
return;
} else if (writeHeaders[stream.getStreamIndex()]) {
logger.debug("has writen headers");
return;
}
int dataSize = 0;
ChannelBuffer buffer = ChannelBuffers.dynamicBuffer(1024);
AVStreamExtra extra = stream.getExtra();
if (extra instanceof H264Extra) {
H264Extra h264 = (H264Extra) extra;
ByteBuffer profile = h264.readProfile();
if (null == profile || profile.remaining() != 3) {
logger.warn("H264.profile is NOT FOUND");
return;
}
ChannelBuffer avc = ChannelBuffers.buffer(128);
avc.writeByte(0x17); // key frame + avc
avc.writeByte(0x00); // avc sequence header
avc.writeMedium(0x00); // Composition time offset
avc.writeByte(0x01);
avc.writeBytes(profile);
avc.writeByte(0xFF); // 4 byte for nal header length
// sps(s)
ByteBuffer sps = h264.readSps();
avc.writeByte(0xE0 | 0x01);
avc.writeShort(sps.remaining());
avc.writeBytes(sps);
// pps(s)
ByteBuffer pps = h264.readPps();
avc.writeByte(0x01);
avc.writeShort(pps.remaining());
avc.writeBytes(pps);
dataSize = avc.readableBytes();
buffer.writeByte(0x09); // video type
buffer.writeMedium(dataSize);
buffer.writeInt(0); // timestamp
buffer.writeMedium(0); // stream id
buffer.writeBytes(avc);
buffer.writeInt(11 + dataSize);
buffer.readBytes(out, buffer.readableBytes());
writeHeaders[stream.getStreamIndex()] = true;
} else if (extra instanceof AACExtra) {
AACExtra aac = (AACExtra) extra;
ByteBuffer aacHeader = ByteBuffer.allocate(4);
aacHeader.put((byte) 0xAF); // aac, 44100, 2 channels, stereo
aacHeader.put((byte) 0x00); // aac header
int objectType = aac.getObjectType();
int sampleRateIndex = aac.getSampleRateIndex();
int numChannels = aac.getNumChannels();
BitWriter w = new BitWriter(aacHeader);
w.writeNBit(objectType, 5);
w.writeNBit(sampleRateIndex, 4);
w.writeNBit(numChannels, 4);
w.writeNBit(0, 1); // frame length - 1024 samples
w.writeNBit(0, 1); // does not depend on core coder
w.writeNBit(0, 1); // is not extension
w.flush();
aacHeader.flip();
dataSize = aacHeader.remaining();
buffer.writeByte(0x08);
buffer.writeMedium(dataSize); // data size
buffer.writeInt(0x00); // timestamp
buffer.writeMedium(0x00); // stream id
buffer.writeBytes(aacHeader); // data
buffer.writeInt(11 + dataSize); // pre tag size
buffer.readBytes(out, buffer.readableBytes());
writeHeaders[stream.getStreamIndex()] = true;
} else if (null == stream.getExtra()) {
logger.warn("no stream extra found {}", stream.getFormat());
} else {
logger.warn("unsupported {}", stream);
}
}
