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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 JPEG video (RFC 2435)
// Implementation
#include "JPEGVideoRTPSink.hh"
#include "JPEGVideoSource.hh"
JPEGVideoRTPSink
::JPEGVideoRTPSink(UsageEnvironment& env, Groupsock* RTPgs)
: VideoRTPSink(env, RTPgs, 26, 90000, "JPEG") {
}
JPEGVideoRTPSink::~JPEGVideoRTPSink() {
}
JPEGVideoRTPSink*
JPEGVideoRTPSink::createNew(UsageEnvironment& env, Groupsock* RTPgs) {
return new JPEGVideoRTPSink(env, RTPgs);
}
Boolean JPEGVideoRTPSink::sourceIsCompatibleWithUs(MediaSource& source) {
return source.isJPEGVideoSource();
}
Boolean JPEGVideoRTPSink
::frameCanAppearAfterPacketStart(unsigned char const* /*frameStart*/,
unsigned /*numBytesInFrame*/) const {
// A packet can contain only one frame
return False;
}
void JPEGVideoRTPSink
::doSpecialFrameHandling(unsigned fragmentationOffset,
unsigned char* /*frameStart*/,
unsigned /*numBytesInFrame*/,
struct timeval frameTimestamp,
unsigned numRemainingBytes) {
// Our source is known to be a JPEGVideoSource
JPEGVideoSource* source = (JPEGVideoSource*)fSource;
u_int8_t mainJPEGHeader[8]; // the special header
mainJPEGHeader[0] = 0; // Type-specific
mainJPEGHeader[1] = fragmentationOffset >> 16;
mainJPEGHeader[2] = fragmentationOffset >> 8;
mainJPEGHeader[3] = fragmentationOffset;
mainJPEGHeader[4] = source->type();
mainJPEGHeader[5] = source->qFactor();
mainJPEGHeader[6] = source->width();
mainJPEGHeader[7] = source->height();
setSpecialHeaderBytes(mainJPEGHeader, sizeof mainJPEGHeader);
if (fragmentationOffset == 0 && source->qFactor() >= 128) {
// There is also a Quantization Header:
u_int8_t precision;
u_int16_t length;
u_int8_t const* quantizationTables
= source->quantizationTables(precision, length);
unsigned const quantizationHeaderSize = 4 + length;
u_int8_t* quantizationHeader = new u_int8_t[quantizationHeaderSize];
quantizationHeader[0] = 0; // MBZ
quantizationHeader[1] = precision;
quantizationHeader[2] = length >> 8;
quantizationHeader[3] = length&0xFF;
if (quantizationTables != NULL) { // sanity check
for (u_int16_t i = 0; i < length; ++i) {
quantizationHeader[4+i] = quantizationTables[i];
}
}
setSpecialHeaderBytes(quantizationHeader, quantizationHeaderSize,
sizeof mainJPEGHeader /* start position */);
delete[] quantizationHeader;
}
if (numRemainingBytes == 0) {
// This packet contains the last (or only) fragment of the frame.
// Set the RTP 'M' ('marker') bit:
setMarkerBit();
}
// Also set the RTP timestamp:
setTimestamp(frameTimestamp);
}
unsigned JPEGVideoRTPSink::specialHeaderSize() const {
// Our source is known to be a JPEGVideoSource
JPEGVideoSource* source = (JPEGVideoSource*)fSource;
unsigned headerSize = 8; // by default
if (curFragmentationOffset() == 0 && source->qFactor() >= 128) {
// There is also a Quantization Header:
u_int8_t dummy;
u_int16_t quantizationTablesSize;
(void)(source->quantizationTables(dummy, quantizationTablesSize));
headerSize += 4 + quantizationTablesSize;
}
// Note: We assume that there are no 'restart markers'
return headerSize;
}
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