// Calculate the number of samples per packet
size_t MastCodec_MPA::frames_per_packet_internal( size_t max_bytes )
{
int frames_per_packet = max_bytes/twolame_get_framelength( this->twolame );
MAST_DEBUG("MPEG Audio Frames per Packet: %d", frames_per_packet );
return frames_per_packet*TWOLAME_SAMPLES_PER_FRAME;
}
/*
mast_fill_input_buffer()
Make sure input buffer if full of audio
*/
size_t mast_fill_input_buffer( MastAudioBuffer* buffer )
{
size_t total_read = 0;
int frames_wanted = buffer->get_write_space();
int frames_read = 0;
if (frames_wanted==0) {
// No audio wanted
MAST_DEBUG( "Tried to fill buffer when it is full" );
return 0;
}
// Loop until buffer is full
while( frames_wanted > 0 ) {
frames_wanted = buffer->get_write_space();
frames_read = sf_readf_float( g_input_file, buffer->get_write_ptr(), frames_wanted );
// Add on the frames read
if (frames_read > 0) {
buffer->add_frames( frames_read );
total_read += frames_read;
}
// Reached end of file?
if (frames_read < frames_wanted) {
MAST_DEBUG("Reached end of file (frames_wanted=%d, frames_read=%d)", frames_wanted, frames_read);
if (g_loop_file) {
// Seek back to the beginning
if (sf_seek( g_input_file, 0, SEEK_SET )) {
MAST_ERROR("Failed to seek to start of file: %s", sf_strerror( g_input_file ) );
return 0;
}
} else {
// Reached end of file (and don't want to loop)
break;
}
}
}
if (total_read == 0) {
MAST_ERROR("Failed to read from file: %s", sf_strerror( g_input_file ) );
}
return total_read;
}
// Constructors
MastTool::MastTool( const char* tool_name, RtpSessionMode mode )
{
int log_level = ORTP_WARNING|ORTP_ERROR|ORTP_FATAL;
// Initialise defaults
this->session = NULL;
this->profile = &av_profile;
this->mimetype = new MastMimeType();
this->payloadtype = NULL;
this->payloadtype_index = -1;
this->tool_name = tool_name;
this->payload_size_limit = DEFAULT_PAYLOAD_LIMIT;
// Initialise the oRTP library
ortp_init();
// Set the logging message level
#ifdef DEBUGGING
MAST_DEBUG( "Compiled with debugging enabled" );
log_level |= ORTP_DEBUG;
log_level |= ORTP_MESSAGE;
#endif
ortp_set_log_level_mask(log_level);
// Create RTP session
session = rtp_session_new( mode );
if (session==NULL) {
MAST_FATAL( "Failed to create oRTP session.\n" );
}
// Enabled multicast loopback
rtp_session_set_multicast_loopback(session, TRUE);
// Callbacks
rtp_session_signal_connect(session,"ssrc_changed",(RtpCallback)ssrc_changed_cb, 0);
rtp_session_signal_connect(session,"payload_type_changed",(RtpCallback)pt_changed_cb, 0);
rtp_session_signal_connect(session,"network_error",(RtpCallback)network_error_cb, 0);
// Set the MPEG Audio payload type to 14 in the AV profile
rtp_profile_set_payload(profile, RTP_MPEG_AUDIO_PT, &payload_type_mpeg_audio);
// Set RTCP parameters
this->set_source_sdes();
}
// Callback called by JACK when buffersize changes
static int buffersize_callback(jack_nframes_t nframes, void *arg)
{
MastSendTool* tool = (MastSendTool*)arg;
int channels = tool->get_input_channels();
MAST_DEBUG("JACK buffer size is %d samples long", nframes);
// (re-)allocate conversion buffer
g_interleavebuf = (jack_default_audio_sample_t*)
realloc( g_interleavebuf, nframes * sizeof(float) * channels );
if (g_interleavebuf == NULL) {
MAST_FATAL("Failed to (re-)allocate the convertion buffer");
}
// Success
return 0;
}
int MastCodec_MPA::set_param_internal( const char* name, const char* value )
{
/* Parameters listed in RFC3555 for audio/MPA:
layer: 1,2,3
samplerate:
mode: "stereo", "joint_stereo", "single_channel", "dual_channel"
bitrate: the data rate for the audio bit stream
ptime: duration of each packet in milliseconds
maxptime: maximum duration of each packet in milliseconds
Example:
audio/MPA;layer=2;mode=stereo;bitrate=160;
*/
if (strcmp(name, "layer")==0) {
int layer = atoi(value);
if (layer!=2) return -2;
} else if (strcmp(name, "mode")==0) {
TWOLAME_MPEG_mode mode;
if (strcmp(value, "stereo")==0) mode = TWOLAME_STEREO;
else if (strcmp(value, "joint_stereo")==0) mode = TWOLAME_JOINT_STEREO;
else if (strcmp(value, "single_channel")==0) mode = TWOLAME_MONO;
else if (strcmp(value, "dual_channel")==0) mode = TWOLAME_DUAL_CHANNEL;
else return -2;
if (twolame_set_mode( this->twolame, mode )) {
MAST_WARNING("Failed to set mode");
}
} else if (strcmp(name, "bitrate")==0) {
int bitrate = atoi(value);
if (twolame_set_bitrate( this->twolame, bitrate )) {
MAST_WARNING("Failed to set bitrate");
} else {
MAST_DEBUG("Set bitrate to %d", bitrate);
}
} else {
// Unsupported parameter
return -1;
}
// Success
return 0;
}
/* Take an hex SSRC string (from command line) and set it for session */
void MastTool::set_session_ssrc( const char* ssrc_str )
{
int ssrc = 0;
// Remove 0x from the start of the string
if (optarg[0] == '0' && (optarg[1] == 'x' || optarg[1] == 'X')) {
ssrc_str += 2;
}
// Parse the hexadecimal number into an integer
if (sscanf(ssrc_str, "%x", &ssrc)<=0) {
MAST_ERROR("SSRC should be a hexadeicmal number");
return;
}
// Set it in the session
MAST_DEBUG( "SSRC for session set to 0x%x", ssrc );
rtp_session_set_ssrc( session, ssrc );
}
int main(int argc, char **argv)
{
MastTool* tool = NULL;
RtpProfile* profile = &av_profile;
PayloadType* pt = NULL;
FILE* output = NULL;
mblk_t* packet = NULL;
int ts_diff = 0;
int ts = 0;
// Create an RTP session
tool = new MastTool( MAST_TOOL_NAME, RTP_SESSION_RECVONLY );
tool->enable_scheduling();
// Parse the command line arguments
// and configure the session
parse_cmd_line( argc, argv, tool );
// Recieve an initial packet
packet = tool->wait_for_rtp_packet();
if (packet == NULL) MAST_FATAL("Failed to receive an initial packet");
// Lookup the payload type
pt = rtp_profile_get_payload( profile, rtp_get_payload_type( packet ) );
if (pt == NULL) MAST_FATAL( "Payload type %d isn't registered with oRTP", rtp_get_payload_type( packet ) );
fprintf(stderr, "Payload type: %s\n", payload_type_get_rtpmap( pt ));
// Work out the duration of the packet
ts_diff = mast_rtp_packet_duration( packet );
MAST_DEBUG("ts_diff = %d", ts_diff);
// Open the output file
output = open_output_file( g_filename );
if (output==NULL) MAST_FATAL( "failed to open output file" );
// We can free the packet now
freemsg( packet );
// Setup signal handlers
mast_setup_signals();
// The main loop
while( mast_still_running() )
{
// Read in a packet
packet = rtp_session_recvm_with_ts( tool->get_session(), ts );
if (packet==NULL) {
MAST_DEBUG( "packet is NULL" );
} else {
int data_len = mast_rtp_packet_size( packet );
if (data_len==0) {
MAST_WARNING("Failed to get size of packet's payload");
} else {
unsigned char* data_ptr = packet->b_cont->b_rptr;
int bytes_written = 0;
// Skip the extra header for MPA payload
if (rtp_get_payload_type( packet ) == RTP_MPEG_AUDIO_PT) {
data_ptr += 4;
data_len -= 4;
}
// Update the timestamp difference
ts_diff = mast_rtp_packet_duration( packet );
MAST_DEBUG("ts_diff = %d", ts_diff);
MAST_DEBUG("data_len = %d", data_len);
// Write to disk
bytes_written = fwrite( data_ptr, 1, data_len, output );
if (bytes_written != data_len) {
MAST_ERROR("Failed to write data to disk: %s", strerror(errno) );
break;
}
}
}
// Increment the timestamp for the next packet
ts += ts_diff;
}
// Close output file
if (fclose( output )) {
MAST_ERROR("Failed to close output file:\n%s", strerror(errno));
}
// Close RTP session
delete tool;
// Success
return 0;
}