@Override
    public void writeHeader() throws IOException {
        // create a buffer
        ByteBuffer buf = ByteBuffer.allocate(HEADER_LENGTH + 4); // FLVHeader (9 bytes) + PreviousTagSize0 (4 bytes)
        // instance an flv header
        FLVHeader flvHeader = new FLVHeader();
        flvHeader.setFlagAudio(audioCodecId != -1 ? true : false);
        flvHeader.setFlagVideo(videoCodecId != -1 ? true : false);
        // write the flv header in the buffer
        flvHeader.write(buf);
        // the final version of the file will go here
        createOutputFile();
        // write header to output channel
        bytesWritten = fileChannel.write(buf);
        assert ((HEADER_LENGTH + 4) - bytesWritten == 0);
        log.debug("Header size: {} bytes written: {}", (HEADER_LENGTH + 4), bytesWritten);
        buf.clear();
        buf = null;
    }
@ Override public void writeHeader ( ) throws IOException { ByteBuffer buf = ByteBuffer . allocate ( HEADER_LENGTH + 4 ) ; FLVHeader flvHeader = new FLVHeader ( ) ; flvHeader . setFlagAudio ( audioCodecId != - 1 ? true : false ) ; flvHeader . setFlagVideo ( videoCodecId != - 1 ? true : false ) ; flvHeader . write ( buf ) ; createOutputFile ( ) ; bytesWritten = fileChannel . write ( buf ) ; assert ( ( HEADER_LENGTH + 4 ) - bytesWritten == 0 ) ; log . debug ( "Header size: {} bytes written: {}" , ( HEADER_LENGTH + 4 ) , bytesWritten ) ; buf . clear ( ) ; buf = null ; }
Writes the header bytes

@throws IOException
Any I/O exception