1 | /********** |
2 | This library is free software; you can redistribute it and/or modify it under |
3 | the terms of the GNU Lesser General Public License as published by the |
4 | Free Software Foundation; either version 3 of the License, or (at your |
5 | option) any later version. (See <http://www.gnu.org/copyleft/lesser.html>.) |
6 | |
7 | This library is distributed in the hope that it will be useful, but WITHOUT |
8 | ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS |
9 | FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for |
10 | more details. |
11 | |
12 | You should have received a copy of the GNU Lesser General Public License |
13 | along with this library; if not, write to the Free Software Foundation, Inc., |
14 | 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA |
15 | **********/ |
16 | // "liveMedia" |
17 | // Copyright (c) 1996-2020 Live Networks, Inc. All rights reserved. |
18 | // RTP sink for DV video (RFC 3189) |
19 | // (Thanks to Ben Hutchings for prototyping this.) |
20 | // Implementation |
21 | |
22 | #include "DVVideoRTPSink.hh" |
23 | |
24 | ////////// DVVideoRTPSink implementation ////////// |
25 | |
26 | DVVideoRTPSink |
27 | ::DVVideoRTPSink(UsageEnvironment& env, Groupsock* RTPgs, unsigned char rtpPayloadFormat) |
28 | : VideoRTPSink(env, RTPgs, rtpPayloadFormat, 90000, "DV" ), |
29 | fFmtpSDPLine(NULL) { |
30 | } |
31 | |
32 | DVVideoRTPSink::~DVVideoRTPSink() { |
33 | delete[] fFmtpSDPLine; |
34 | } |
35 | |
36 | DVVideoRTPSink* |
37 | DVVideoRTPSink::createNew(UsageEnvironment& env, Groupsock* RTPgs, unsigned char rtpPayloadFormat) { |
38 | return new DVVideoRTPSink(env, RTPgs, rtpPayloadFormat); |
39 | } |
40 | |
41 | Boolean DVVideoRTPSink::sourceIsCompatibleWithUs(MediaSource& source) { |
42 | // Our source must be an appropriate framer: |
43 | return source.isDVVideoStreamFramer(); |
44 | } |
45 | |
46 | void DVVideoRTPSink::doSpecialFrameHandling(unsigned fragmentationOffset, |
47 | unsigned char* /*frameStart*/, |
48 | unsigned /*numBytesInFrame*/, |
49 | struct timeval framePresentationTime, |
50 | unsigned numRemainingBytes) { |
51 | if (numRemainingBytes == 0) { |
52 | // This packet contains the last (or only) fragment of the frame. |
53 | // Set the RTP 'M' ('marker') bit: |
54 | setMarkerBit(); |
55 | } |
56 | |
57 | // Also set the RTP timestamp: |
58 | setTimestamp(framePresentationTime); |
59 | } |
60 | |
61 | unsigned DVVideoRTPSink::computeOverflowForNewFrame(unsigned newFrameSize) const { |
62 | unsigned initialOverflow = MultiFramedRTPSink::computeOverflowForNewFrame(newFrameSize); |
63 | |
64 | // Adjust (increase) this overflow, if necessary, so that the amount of frame data that we use is an integral number |
65 | // of DIF blocks: |
66 | unsigned numFrameBytesUsed = newFrameSize - initialOverflow; |
67 | initialOverflow += numFrameBytesUsed%DV_DIF_BLOCK_SIZE; |
68 | |
69 | return initialOverflow; |
70 | } |
71 | |
72 | char const* DVVideoRTPSink::auxSDPLine() { |
73 | // Generate a new "a=fmtp:" line each time, using parameters from |
74 | // our framer source (in case they've changed since the last time that |
75 | // we were called): |
76 | DVVideoStreamFramer* framerSource = (DVVideoStreamFramer*)fSource; |
77 | if (framerSource == NULL) return NULL; // we don't yet have a source |
78 | |
79 | return auxSDPLineFromFramer(framerSource); |
80 | } |
81 | |
82 | char const* DVVideoRTPSink::auxSDPLineFromFramer(DVVideoStreamFramer* framerSource) { |
83 | char const* const profileName = framerSource->profileName(); |
84 | if (profileName == NULL) return NULL; |
85 | |
86 | char const* const fmtpSDPFmt = "a=fmtp:%d encode=%s;audio=bundled\r\n" ; |
87 | unsigned fmtpSDPFmtSize = strlen(fmtpSDPFmt) |
88 | + 3 // max payload format code length |
89 | + strlen(profileName); |
90 | delete[] fFmtpSDPLine; // if it already exists |
91 | fFmtpSDPLine = new char[fmtpSDPFmtSize]; |
92 | sprintf(fFmtpSDPLine, fmtpSDPFmt, rtpPayloadType(), profileName); |
93 | |
94 | return fFmtpSDPLine; |
95 | } |
96 | |