一个基于jrtplib的轻量级rtsp客户端(myrtspclient)——实现篇：用户接口层之提取媒体流数据

 1 uint8_t * RtspClient::GetMediaData(string media_type, uint8_t * buf, size_t * size, size_t max_size) 
 2 {
 3         MyRegex Regex;
 4         map<string, MediaSession>::iterator it;
 5         bool IgnoreCase = true;
 6         if(!buf) return NULL;
 7         if(!size) return NULL;
 8 
 9         *size = 0; 
10 
11         for(it = MediaSessionMap->begin(); it != MediaSessionMap->end(); it++) {
12                 if(Regex.Regex(it->first.c_str(), media_type.c_str(), IgnoreCase)) break;
13         }
14 
15         if(it == MediaSessionMap->end()) {
16                 fprintf(stderr, "%s: No such media session
", __func__);
17                 return NULL;
18         }
19 
20         if(it->second.MediaType == "video") return GetVideoData(&(it->second), buf, size, max_size);
21         if(it->second.MediaType == "audio") return GetAudioData(&(it->second), buf, size, max_size);
22         return NULL;
23 }

 1 uint8_t * RtspClient::GetVideoData(MediaSession * media_session, uint8_t * buf, size_t * size, size_t max_size, bool get_vps_sps_pps_periodly) 
 2 {
 3     if(!media_session || !buf || !size) return NULL;
 4 
 5     *size = 0;
 6 
 7     const size_t GetSPS_PPS_Period = GET_SPS_PPS_PERIOD; // 30 times
 8     if(true == get_vps_sps_pps_periodly) {
 9         if(GetVideoDataCount >= GetSPS_PPS_Period) {
10             GetVideoDataCount = 0;
11 
12             const size_t NALU_StartCodeSize = 4;
13             size_t SizeTmp = 0;
14             if(!GetVPSNalu(buf + (*size), &SizeTmp) || SizeTmp <= NALU_StartCodeSize) {
15                 // fprintf(stderr, "33[31mWARNING: No H264 VPS33[0m
");
16             } else {
17                 *size += SizeTmp;
18             }
19             if(!GetSPSNalu(buf + (*size), &SizeTmp) || SizeTmp <= NALU_StartCodeSize) {
20                 fprintf(stderr, "33[31mWARNING: No SPS33[0m
");
21             } else {
22                 *size += SizeTmp;
23             }
24             if(!GetPPSNalu(buf + (*size), &SizeTmp) || SizeTmp <= NALU_StartCodeSize) {
25                 fprintf(stderr, "33[31mWARNING: No PPS33[0m
");
26             } else {
27                 *size += SizeTmp;
28             }
29             return buf;
30         } else {
31             GetVideoDataCount++;
32         }
33     }
34 
35     size_t SizeTmp = 0;
36     bool EndFlag = false;
37     NALUTypeBase * NALUTypeBaseTmp = NULL;
38     NALUTypeBase * NALUType;
39 
40     int PM = media_session->Packetization;
41     if(!IS_PACKET_MODE_VALID(PM)) {
42         cerr << "WARNING:Invalid Packetization Mode" << endl;
43         return NULL;
44     }
45     if(media_session->EncodeType == "H264") {
46         NALUTypeBaseTmp = &NaluBaseType_H264Obj;
47     } else if (media_session->EncodeType == "H265") {
48         NALUTypeBaseTmp = &NaluBaseType_H265Obj;
49     } else {
50         // Unknown Nalu type
51         printf("Unsupported codec type: %s
", media_session->EncodeType.c_str());
52         return NULL;
53     }
54 
55     do {
56         EndFlag = true;
57         if(!media_session->GetMediaData(VideoBuffer.Buf, &SizeTmp)) return NULL;
58         if(0 == SizeTmp) {
59             cerr << "No RTP data" << endl;
60             return NULL;
61         }
62         int NT; 
63         NT = NALUTypeBaseTmp->ParseNALUHeader_Type(VideoBuffer.Buf);
64         NALUType = NALUTypeBaseTmp->GetNaluRtpType(PM, NT);
65         if(NULL == NALUType) {
66             printf("Unknown NALU Type: %s
", media_session->EncodeType.c_str());
67             return NULL;
68         }
69 
70         if(SizeTmp > VideoBuffer.Size) {
71             cerr << "Error: RTP Packet too large(" << SizeTmp << " bytes > " << VideoBuffer.Size << "bytes)" << endl;
72             return NULL;
73         }
74 
75         if(*size + SizeTmp > max_size) {
76             fprintf(stderr, "33[31mWARNING: NALU truncated because larger than buffer: %u(NALU size) > %u(Buffer size)33[0m
", *size + SizeTmp, max_size);
77             return buf;
78         }
79 
80         SizeTmp = NALUType->CopyData(buf + (*size), VideoBuffer.Buf, SizeTmp);
81         *size += SizeTmp;
82         EndFlag = NALUType->GetEndFlag();
83     } while(!EndFlag);
84 
85     return buf;
86 }

 1 uint8_t * RtspClient::GetAudioData(MediaSession * media_session, uint8_t * buf, size_t * size, size_t max_size)
 2 {
 3         if(!media_session || !buf || !size) return NULL;
 4 
 5         *size = 0;
 6 
 7         size_t SizeTmp = 0;
 8         MPEGTypeBase * MPEGType;
 9 
10         if(!media_session->GetMediaData(AudioBuffer.Buf, &SizeTmp)) return NULL;
11         if(0 == SizeTmp) {
12                 cerr << "No RTP data" << endl;
13                 return NULL;
14         }
15 
16         MPEGType = &MPEG_AudioObj;
17 
18         if(SizeTmp > AudioBuffer.Size) {
19                 cerr << "Error: RTP Packet too large(" << SizeTmp << " bytes > " << AudioBuffer.Size << "bytes)" << endl;
20                 return NULL;
21         }
22 
23         if(*size + SizeTmp > max_size) {
24                 fprintf(stderr, "33[31mWARNING: NALU truncated because larger than buffer: %u(NALU size) > %u(Buffer size)33[0m
", *size + SizeTmp, max_size);
25                 return buf;
26         }
27 
28         SizeTmp = MPEGType->CopyData(buf + (*size), AudioBuffer.Buf, SizeTmp);
29         *size += SizeTmp;
30 
31         return buf;
32 }