TAO_AV: RTP_Packet Class Reference

List of all members.


Public Member Functions
	RTP_Packet (char *buffer, int length)
	Constructor for incoming RTP packets.
	RTP_Packet (unsigned char padding, unsigned char marker, unsigned char payloadType, ACE_UINT32 sequenceNumber, ACE_UINT32 timeStamp, ACE_UINT32 syncSource, unsigned char contribSourcCount, ACE_UINT32 contribSourceList[], char *data, ACE_UINT16 dataSize)
	Constructor for outgoing RTP packets.
	~RTP_Packet (void)
	Destructor.
ACE_UINT16	packet_size (void)
	Returns the size of the RTP packet in bytes.
ACE_UINT16	payload_size (void)
	Returns the size of the payload in bytes.
void	get_frame_info (TAO_AV_frame_info *frame_info)
	Populates the passed in frame_info.
int	is_valid (void)
	Returns 1 if packet is valid and 0 if not.
unsigned int	ver (void)
	Returns the RTP version of the packet.
unsigned int	pad (void)
	Returns 1 if the padding bit is set, 0 if not.
unsigned int	ext (void)
	Returns 1 if the header extension bit is set, 0 if not.
unsigned int	ext_bytes (void)
	Returns the number of bytes in the header extension or 0 if no extension.
unsigned int	cc (void)
unsigned int	mrk (void)
	Returns 1 if the marker bit is set, 0 if not.
unsigned int	pt (void)
	Returns the payload type of the packet.
ACE_UINT16	sn (void)
	Returns the sequence number of the packet.
ACE_UINT32	ts (void)
	Returns the timestamp of the packet.
ACE_UINT32	ssrc (void)
	Returns the synchronization source id of the packet.
void	get_csrc_list (ACE_UINT32 **csrc_list, ACE_UINT16 &length)
void	get_payload (char **payload, ACE_UINT16 &size)
void	get_packet_data (char **packet, ACE_UINT16 &size)
Private Attributes
char	packet_ [RTP_MTU]
	Local buffer to hold the RTP packet.
ACE_UINT32	host_byte_order_csrc_list_ [15]
char	host_byte_order_payload_ [RTP_MTU]
	Local buffer to hold the payload with the values stored in host byte order.
unsigned int	extension_bytes_
	The number of bytes in the header extension - 0 if no extension.
ACE_UINT16	packet_size_
	The size of the overall data packet.
ACE_UINT16	payload_size_
	The size of the payload portion of the packet.

Detailed Description

Constructor & Destructor Documentation

TAO_BEGIN_VERSIONED_NAMESPACE_DECL RTP_Packet::RTP_Packet	(	char *	buffer,
		int	length
	)

Constructor for incoming RTP packets.

Definition at line 49 of file RTP.cpp.

References extension_bytes_, host_byte_order_payload_, ACE_OS::memcpy(), packet_size_, payload_size_, RTP_PT_L16_MONO, RTP_PT_L16_OTHER, and RTP_PT_L16_STEREO.

00050 {
00051   // skip the standard header info
00052   int index = 12;
00053 
00054   ACE_OS::memcpy(this->packet_, buffer, length);
00055 
00056   for (int j=0; j<(int)this->cc(); j++)
00057     {
00058       this->host_byte_order_csrc_list_[j] = ntohl(*(ACE_UINT32*)&buffer[index]);
00059       index+=4;
00060     }
00061 
00062   // ignore the header extension if there is one
00063   if (this->ext())
00064     {
00065       index+=2;
00066       int extension_data_size = ntohs(*(ACE_UINT16*)&buffer[index]);
00067       index+=2;
00068       index+=extension_data_size;
00069 
00070       this->extension_bytes_ = 4 + extension_data_size;
00071     }
00072   else
00073     this->extension_bytes_ = 0;
00074 
00075   this->packet_size_ = static_cast<ACE_UINT16> (length);
00076   this->payload_size_ = static_cast<ACE_UINT16> (length-index);
00077 
00078   // This is necessary only for payload types that have 16 bit values to correct
00079   //  the network byte ordering.
00080   if ((this->pt() == RTP_PT_L16_OTHER) ||
00081       (this->pt() == RTP_PT_L16_STEREO) ||
00082       (this->pt() == RTP_PT_L16_MONO))
00083     {
00084       for (int i=0; i < payload_size_; i+=2)
00085         {
00086           *(ACE_UINT16*)&this->host_byte_order_payload_[i] = ntohs(*(ACE_UINT16*)&this->packet_[index]);
00087           index+=2;
00088         }
00089     }
00090   else
00091     for (int i=0; i<this->payload_size_; i++)
00092       {
00093         this->host_byte_order_payload_[i] = this->packet_[index];
00094         index++;
00095       }
00096 }

RTP_Packet::RTP_Packet	(	unsigned char	padding,
		unsigned char	marker,
		unsigned char	payloadType,
		ACE_UINT32	sequenceNumber,
		ACE_UINT32	timeStamp,
		ACE_UINT32	syncSource,
		unsigned char	contribSourcCount,
		ACE_UINT32	contribSourceList[],
		char *	data,
		ACE_UINT16	dataSize
	)

Constructor for outgoing RTP packets.

RTP_Packet::~RTP_Packet ( void )

Destructor.

Definition at line 178 of file RTP.cpp.

00179 {
00180 }

Member Function Documentation

unsigned int RTP_Packet::cc ( void )

Returns the contributing source count. This should only be non-zero for mixers.

Definition at line 213 of file RTP.cpp.

Referenced by get_csrc_list().

00214 {
00215   return ( this->packet_[0] & 0x0F ) ;
00216 }

unsigned int RTP_Packet::ext ( void )

Returns 1 if the header extension bit is set, 0 if not.

Definition at line 207 of file RTP.cpp.

00208 {
00209   return ( this->packet_[0] & 0x10 ) >> 4;
00210 }

unsigned int RTP_Packet::ext_bytes ( void )

Returns the number of bytes in the header extension or 0 if no extension.

Definition at line 249 of file RTP.cpp.

References extension_bytes_.

00250 {
00251   return this->extension_bytes_;
00252 }

void RTP_Packet::get_csrc_list	(	ACE_UINT32 **	csrc_list,
		ACE_UINT16 &	length
	)

Returns a pointer to the local contributing source list and its length. This should be empty except for mixers. RTP_Packet retains ownership.

Definition at line 294 of file RTP.cpp.

References cc(), and host_byte_order_csrc_list_.

00295 {
00296   *csrc_list = this->host_byte_order_csrc_list_;
00297   length = static_cast<ACE_UINT16> (this->cc ());
00298 }

void RTP_Packet::get_frame_info ( TAO_AV_frame_info * frame_info )

Populates the passed in frame_info.

Definition at line 255 of file RTP.cpp.

References TAO_AV_frame_info::format, mrk(), pt(), TAO_AV_frame_info::sequence_num, sn(), ssrc(), TAO_AV_frame_info::ssrc, TAO_AV_frame_info::timestamp, and ts().

Referenced by TAO_AV_RTP_Object::handle_input().

00256 {
00257   frame_info->timestamp = this->mrk();
00258   frame_info->timestamp = this->ts();
00259   frame_info->ssrc = this->ssrc();
00260   frame_info->sequence_num = this->sn();
00261   frame_info->format = static_cast<CORBA::Octet> (this->pt());
00262 }

void RTP_Packet::get_packet_data	(	char **	packet,
		ACE_UINT16 &	size
	)

Returns a pointer to the locally stored rtp packet and its size in bytes. RTP_Packet retains ownership.

Definition at line 308 of file RTP.cpp.

References packet_, and packet_size_.

Referenced by TAO_AV_RTP_Object::send_frame().

00309 {
00310   *packet = this->packet_;
00311   length = this->packet_size_;
00312 }

void RTP_Packet::get_payload	(	char **	payload,
		ACE_UINT16 &	size
	)

Returns a pointer to the locally stored payload and its size in bytes. The payload is returned in host byte order. RTP_Packet retains ownership.

Definition at line 301 of file RTP.cpp.

References host_byte_order_payload_.

Referenced by TAO_AV_RTP_Object::handle_input().

00302 {
00303   *payload = this->host_byte_order_payload_ ;
00304   length = this->payload_size_;
00305 }

int RTP_Packet::is_valid ( void )

Returns 1 if packet is valid and 0 if not.

Definition at line 265 of file RTP.cpp.

References extension_bytes_, RTCP_PT_RR, RTCP_PT_SR, and RTP_VERSION.

Referenced by RTCP_Channel_In::recv_rtp_packet().

00266 {
00267   // taken from RFC 1889 - Appendix A.1
00268 
00269   // make sure the RTP version is correct
00270   if (this->ver() != RTP_VERSION)
00271     return 0;
00272 
00273   // make sure the payload type is not SR or RR
00274   if ((this->pt() == RTCP_PT_SR) || (this->pt() == RTCP_PT_RR))
00275     return 0;
00276 
00277   // if the p bit is set, the last octet of the packet must contain a valid
00278   // octet count, in particular, less than the total packet length minus
00279   // the header size.
00280   if (this->pad() != 0)
00281     if ((unsigned int)this->packet_[this->packet_size_] >=
00282         (this->packet_size_ - (12 + this->cc() + this->extension_bytes_)))
00283       return 0;
00284 
00285   // If there is an extension, it is ignored (taken care of in constructor)
00286 
00287   // The length of the packet must be consistent with CC and payload type (if
00288   // payloads have a known length)
00289 
00290   return 1;
00291 }

unsigned int RTP_Packet::mrk ( void )

Returns 1 if the marker bit is set, 0 if not.

Definition at line 219 of file RTP.cpp.

Referenced by get_frame_info().

00220 {
00221   return ( this->packet_[1] & 0x80 ) >> 7;
00222 }

ACE_UINT16 RTP_Packet::packet_size ( void )

Returns the size of the RTP packet in bytes.

Definition at line 183 of file RTP.cpp.

References packet_size_.

00184 {
00185     return this->packet_size_;
00186 }

unsigned int RTP_Packet::pad ( void )

Returns 1 if the padding bit is set, 0 if not.

Definition at line 201 of file RTP.cpp.

00202 {
00203   return ( this->packet_[0] & 0x20 ) >> 5;
00204 }

ACE_UINT16 RTP_Packet::payload_size ( void )

Returns the size of the payload in bytes.

Definition at line 189 of file RTP.cpp.

Referenced by RTCP_Channel_Out::updateStatistics().

00190 {
00191     return this->payload_size_;
00192 }

unsigned int RTP_Packet::pt ( void )

Returns the payload type of the packet.

Definition at line 225 of file RTP.cpp.

Referenced by get_frame_info(), and RTCP_Channel_In::updateStatistics().

00226 {
00227   return ( this->packet_[1] & 0x7F ) ;
00228 }

ACE_UINT16 RTP_Packet::sn ( void )

Returns the sequence number of the packet.

Definition at line 231 of file RTP.cpp.

Referenced by get_frame_info(), RTCP_Channel_Out::updateStatistics(), and RTCP_Channel_In::updateStatistics().

00232 {
00233   return ntohs(*(ACE_UINT16*)(&this->packet_[2])) ;
00234 }

ACE_UINT32 RTP_Packet::ssrc ( void )

Returns the synchronization source id of the packet.

Definition at line 243 of file RTP.cpp.

Referenced by get_frame_info(), and TAO_AV_RTCP_Callback::receive_frame().

00244 {
00245   return ntohl(*(ACE_UINT32*)(&this->packet_[8])) ;
00246 }

ACE_UINT32 RTP_Packet::ts ( void )

Returns the timestamp of the packet.

Definition at line 237 of file RTP.cpp.

Referenced by get_frame_info(), RTCP_Channel_Out::updateStatistics(), and RTCP_Channel_In::updateStatistics().

00238 {
00239   return ntohl(*(ACE_UINT32*)(&this->packet_[4])) ;
00240 }

unsigned int RTP_Packet::ver ( void )

Returns the RTP version of the packet.

Definition at line 195 of file RTP.cpp.

00196 {
00197   return ( this->packet_[0] & 0xC0 ) >> 6;
00198 }

Member Data Documentation

unsigned int RTP_Packet::extension_bytes_ [private]

The number of bytes in the header extension - 0 if no extension.

Definition at line 345 of file RTP.h.

Referenced by ext_bytes(), is_valid(), and RTP_Packet().

ACE_UINT32 RTP_Packet::host_byte_order_csrc_list_[15] [private]

Local buffer to hold the contributing source list with the values stored in host byte order.

Definition at line 339 of file RTP.h.

Referenced by get_csrc_list().

char RTP_Packet::host_byte_order_payload_[RTP_MTU] [private]

Local buffer to hold the payload with the values stored in host byte order.

Definition at line 342 of file RTP.h.

Referenced by get_payload(), and RTP_Packet().

char RTP_Packet::packet_[RTP_MTU] [private]

Local buffer to hold the RTP packet.

Definition at line 335 of file RTP.h.

Referenced by get_packet_data().

ACE_UINT16 RTP_Packet::packet_size_ [private]

The size of the overall data packet.

Definition at line 348 of file RTP.h.

Referenced by get_packet_data(), packet_size(), and RTP_Packet().

ACE_UINT16 RTP_Packet::payload_size_ [private]

The size of the payload portion of the packet.

Definition at line 351 of file RTP.h.

Referenced by RTP_Packet().

RTP_Packet Class Reference

Public Member Functions

Private Attributes

Detailed Description

Constructor & Destructor Documentation

Member Function Documentation

Member Data Documentation