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/**********
This library is free software; you can redistribute it and/or modify it under
the terms of the GNU Lesser General Public License as published by the
Free Software Foundation; either version 2.1 of the License, or (at your
option) any later version. (See <http://www.gnu.org/copyleft/lesser.html>.)
This library is distributed in the hope that it will be useful, but WITHOUT
ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for
more details.
You should have received a copy of the GNU Lesser General Public License
along with this library; if not, write to the Free Software Foundation, Inc.,
59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
**********/
// "liveMedia"
// Copyright (c) 1996-2005 Live Networks, Inc. All rights reserved.
// RTP sink for MPEG-4 Elementary Stream video (RFC 3016)
// Implementation
#include "MPEG4ESVideoRTPSink.hh"
#include "MPEG4VideoStreamFramer.hh"
MPEG4ESVideoRTPSink
::MPEG4ESVideoRTPSink(UsageEnvironment& env, Groupsock* RTPgs,
unsigned char rtpPayloadFormat,
u_int32_t rtpTimestampFrequency)
: VideoRTPSink(env, RTPgs, rtpPayloadFormat, rtpTimestampFrequency, "MP4V-ES"),
fVOPIsPresent(False), fAuxSDPLine(NULL) {
}
MPEG4ESVideoRTPSink::~MPEG4ESVideoRTPSink() {
delete[] fAuxSDPLine;
}
MPEG4ESVideoRTPSink*
MPEG4ESVideoRTPSink::createNew(UsageEnvironment& env, Groupsock* RTPgs,
unsigned char rtpPayloadFormat,
u_int32_t rtpTimestampFrequency) {
return new MPEG4ESVideoRTPSink(env, RTPgs, rtpPayloadFormat,
rtpTimestampFrequency);
}
Boolean MPEG4ESVideoRTPSink::sourceIsCompatibleWithUs(MediaSource& source) {
// Our source must be an appropriate framer:
return source.isMPEG4VideoStreamFramer();
}
#define VOP_START_CODE 0x000001B6
void MPEG4ESVideoRTPSink
::doSpecialFrameHandling(unsigned fragmentationOffset,
unsigned char* frameStart,
unsigned numBytesInFrame,
struct timeval frameTimestamp,
unsigned numRemainingBytes) {
if (fragmentationOffset == 0) {
// Begin by inspecting the 4-byte code at the start of the frame:
if (numBytesInFrame < 4) return; // shouldn't happen
unsigned startCode = (frameStart[0]<<24) | (frameStart[1]<<16)
| (frameStart[2]<<8) | frameStart[3];
fVOPIsPresent = startCode == VOP_START_CODE;
}
// Set the RTP 'M' (marker) bit iff this frame ends a VOP
// (and there are no fragments remaining).
// This relies on the source being a "MPEG4VideoStreamFramer".
MPEG4VideoStreamFramer* framerSource = (MPEG4VideoStreamFramer*)fSource;
if (framerSource != NULL && framerSource->pictureEndMarker()
&& numRemainingBytes == 0) {
setMarkerBit();
framerSource->pictureEndMarker() = False;
}
// Also set the RTP timestamp. (We do this for each frame
// in the packet, to ensure that the timestamp of the VOP (if present)
// gets used.)
setTimestamp(frameTimestamp);
}
Boolean MPEG4ESVideoRTPSink::allowFragmentationAfterStart() const {
return True;
}
Boolean MPEG4ESVideoRTPSink
::frameCanAppearAfterPacketStart(unsigned char const* /*frameStart*/,
unsigned /*numBytesInFrame*/) const {
// Once we've packed a VOP into the packet, then no other
// frame can be packed into it:
return !fVOPIsPresent;
}
char const* MPEG4ESVideoRTPSink::auxSDPLine() {
// Generate a new "a=fmtp:" line each time, using parameters from
// our framer source (in case they've changed since the last time that
// we were called):
MPEG4VideoStreamFramer* framerSource = (MPEG4VideoStreamFramer*)fSource;
if (framerSource == NULL) return NULL; // we don't yet have a source
u_int8_t profile_level_id = framerSource->profile_and_level_indication();
if (profile_level_id == 0) return NULL; // our source isn't ready
unsigned configLength;
unsigned char* config = framerSource->getConfigBytes(configLength);
if (config == NULL) return NULL; // our source isn't ready
char const* fmtpFmt =
"a=fmtp:%d "
"profile-level-id=%d;"
"config=";
unsigned fmtpFmtSize = strlen(fmtpFmt)
+ 3 /* max char len */
+ 3 /* max char len */
+ 2*configLength /* 2*, because each by prints as 2 chars */
+ 2 /* trailing \r\n */;
char* fmtp = new char[fmtpFmtSize];
sprintf(fmtp, fmtpFmt, rtpPayloadType(), profile_level_id);
char* endPtr = &fmtp[strlen(fmtp)];
for (unsigned i = 0; i < configLength; ++i) {
sprintf(endPtr, "%02X", config[i]);
endPtr += 2;
}
sprintf(endPtr, "\r\n");
delete[] fAuxSDPLine;
fAuxSDPLine = strDup(fmtp);
delete[] fmtp;
return fAuxSDPLine;
}
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