feat: 完成发送RTP视频数据，读取h264文件去掉NALU头，分片传输。

tests/rtpStudy/rtpSendh264.cpp

@@ -0,0 +1,313 @@
+// test : 测试发送RTP视频数据，采用ffplay播放该RTP视频流，H264封装
+
+
+#include <iostream>
+//对于C++而言的网络库，需要引入下面的头文件和lib库
+#ifdef _WIN32
+#include <winsock2.h>
+#include <windows.h>
+//引入ws2tcpip来使用inet_pton
+#include <ws2tcpip.h> 
+#pragma comment(lib, "WS2_32.lib")
+#pragma comment(lib, "wsock32.lib")
+//对于C而言需要引入下面的头文件
+#else
+#include <netinet/in.h>
+#include <sys/types.h>
+#include <sys/socket.h>
+#include <arpa/inet.h>
+#include <errno.h>
+#ifndef INVALID_SOCKET
+#define INVALID_SOCKET	(SOCKET)(~0)
+#endif
+#ifndef SOCKET_ERROR
+#define SOCKET_ERROR	(-1)
+#endif
+#ifndef closesocket
+#define closesocket(x)	close(x)
+#endif
+typedef int SOCKET;
+#endif
+
+#include "test/rtp.h"
+#include <ws2ipdef.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+#include <string.h>
+#include <thread>
+
+#define H264_FILE_NAME  "./test.h264"
+#define CLIENT_IP       "127.0.0.1"   //destination ip
+#define CLIENT_PORT     1234              //destination port
+
+#define FPS             25                
+
+
+//写成内联函数减少开销
+static inline int startCode3(char* buf)
+{
+  if (buf[0] == 0 && buf[1] == 0 && buf[2] == 1)
+    return 1;
+  else
+    return 0;
+}
+
+static inline int startCode4(char* buf)
+{
+  if (buf[0] == 0 && buf[1] == 0 && buf[2] == 0 && buf[3] == 1)
+    return 1;
+  else
+    return 0;
+}
+
+static char* findNextStartCode(char* buf, int len)
+{
+  int i;
+
+  if (len < 3)
+    return NULL;
+
+  for (i = 0; i < len - 3; ++i)
+  {
+    if (startCode3(buf) || startCode4(buf))
+      return buf;
+
+    ++buf;
+  }
+
+  if (startCode3(buf))
+    return buf;
+
+  return NULL;
+}
+
+static int getFrameFromH264File(FILE* fd, char* frame, int size)
+{
+  int rSize, frameSize;
+  char* nextStartCode;
+
+  if (fd < 0)
+    return -1;
+
+  rSize = fread(frame, 1, size, fd);
+  if (!startCode3(frame) && !startCode4(frame))
+    return -1;
+
+  nextStartCode = findNextStartCode(frame + 3, rSize - 3);
+  if (!nextStartCode)
+  {
+    fseek(fd, 0, SEEK_SET);
+    frameSize = rSize;
+  }
+  else
+  {
+    frameSize = (nextStartCode - frame);
+    fseek(fd, frameSize - rSize, SEEK_CUR);
+  }
+
+  return frameSize;
+}
+
+static int createUdpSocket()
+{
+  int fd;
+  int on = 1;
+  //加载winsock 无论是客户端还是服务器都需要
+  WORD socketVersion = MAKEWORD(2, 2);
+  WSADATA wsaData;
+  //初始化socket资源
+  if (WSAStartup(socketVersion, &wsaData) != 0)
+  {
+    return 0;
+  }
+  fd = socket(AF_INET, SOCK_DGRAM, 0);
+  if (fd < 0)
+    return -1;
+
+  setsockopt(fd, SOL_SOCKET, SO_REUSEADDR, (const char*)&on, sizeof(on));
+
+  return fd;
+}
+
+static int rtpSendH264Frame(int socket, char* ip, int16_t port,
+  struct RtpPacket* rtpPacket, uint8_t* frame, uint32_t frameSize)
+{
+  uint8_t naluType; // nalu第一个字节
+  int sendBytes = 0;
+  int ret;
+
+  naluType = frame[0];
+
+  if (frameSize <= RTP_MAX_PKT_SIZE) // nalu长度小于最大包场：单一NALU单元模式
+  {
+    /*
+     *   0 1 2 3 4 5 6 7 8 9
+     *  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+     *  |F|NRI|  Type   | a single NAL unit ... |
+     *  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+     */
+    memcpy(rtpPacket->payload, frame, frameSize);
+    ret = rtpSendPacket(socket, ip, port, rtpPacket, frameSize);
+    if (ret < 0)
+      return -1;
+
+    rtpPacket->rtpHeader.seq++;
+    sendBytes += ret;
+    if ((naluType & 0x1F) == 7 || (naluType & 0x1F) == 8) // 如果是SPS、PPS就不需要加时间戳
+      goto out;
+  }
+  else // nalu长度小于最大包场：分片模式
+  {
+    /*
+     *  0                   1                   2
+     *  0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3
+     * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+     * | FU indicator  |   FU header   |   FU payload   ...  |
+     * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+     */
+
+     /*
+      *     FU Indicator
+      *    0 1 2 3 4 5 6 7
+      *   +-+-+-+-+-+-+-+-+
+      *   |F|NRI|  Type   |
+      *   +---------------+
+      */
+
+      /*
+       *      FU Header
+       *    0 1 2 3 4 5 6 7
+       *   +-+-+-+-+-+-+-+-+
+       *   |S|E|R|  Type   |
+       *   +---------------+
+       */
+
+    int pktNum = frameSize / RTP_MAX_PKT_SIZE;       // 有几个完整的包
+    int remainPktSize = frameSize % RTP_MAX_PKT_SIZE; // 剩余不完整包的大小
+    int i, pos = 1;
+
+    /* 发送完整的包 */
+    for (i = 0; i < pktNum; i++)
+    {
+      rtpPacket->payload[0] = (naluType & 0x60) | 28;
+      rtpPacket->payload[1] = naluType & 0x1F;
+
+      if (i == 0) //第一包数据
+        rtpPacket->payload[1] |= 0x80; // start
+      else if (remainPktSize == 0 && i == pktNum - 1) //最后一包数据
+        rtpPacket->payload[1] |= 0x40; // end
+
+      memcpy(rtpPacket->payload + 2, frame + pos, RTP_MAX_PKT_SIZE);
+      ret = rtpSendPacket(socket, ip, port, rtpPacket, RTP_MAX_PKT_SIZE + 2);
+      if (ret < 0)
+        return -1;
+
+      rtpPacket->rtpHeader.seq++;
+      sendBytes += ret;
+      pos += RTP_MAX_PKT_SIZE;
+    }
+
+    /* 发送剩余的数据 */
+    if (remainPktSize > 0)
+    {
+      rtpPacket->payload[0] = (naluType & 0x60) | 28;
+      rtpPacket->payload[1] = naluType & 0x1F;
+      rtpPacket->payload[1] |= 0x40; //end
+
+      memcpy(rtpPacket->payload + 2, frame + pos, remainPktSize + 2);
+      ret = rtpSendPacket(socket, ip, port, rtpPacket, remainPktSize + 2);
+      if (ret < 0)
+        return -1;
+
+      rtpPacket->rtpHeader.seq++;
+      sendBytes += ret;
+    }
+  }
+
+out:
+
+  return sendBytes;
+}
+
+int main(int argc, char* argv[])
+{
+  int socket;
+  FILE* fd;
+  int fps = 25;
+  int startCode;
+  struct RtpPacket* rtpPacket;
+  uint8_t* frame;
+  uint32_t frameSize;
+  char* fileName;
+  int16_t port;
+
+  std::cout << "please input this video's port" << std::endl;
+  while (std::cin >> port) {
+    if (getchar() == '\n')
+      break;
+  }
+  std::cout << "port is : " << port << std::endl;
+
+  fd = fopen(H264_FILE_NAME, "rb");
+  if (fd < 0)
+  {
+    printf("failed to open %s\n", H264_FILE_NAME);
+    return -1;
+  }
+
+  socket = createUdpSocket();
+  if (socket < 0)
+  {
+    printf("failed to create socket\n");
+    return -1;
+  }
+  // 加入到组播
+  //struct ip_mreq op;  //ip_mreq和ip_mreqn都有相同的效果， 后者是更新的版本多了一个设置级别ifindex，
+  ////但是前者依然可以使用
+  //op.imr_interface.s_addr = INADDR_ANY; // 本地地址
+  //inet_pton(AF_INET, "127.0.0.1", &op.imr_multiaddr.s_addr);
+  ////加入组播
+  //setsockopt(socket, IPPROTO_IP, IP_ADD_MEMBERSHIP, (const char*)&op, sizeof(op));
+
+  rtpPacket = (struct RtpPacket*)malloc(500000);
+  frame = (uint8_t*)malloc(500000);
+
+  rtpHeaderInit(rtpPacket, 0, 0, 0, RTP_VESION, RTP_PAYLOAD_TYPE_H264, 0,
+    0, 0, 0x88923423);
+
+  while (1)
+  {
+    std::cout << "timestamp : " << GetTickCount64() << std::endl;
+    frameSize = getFrameFromH264File(fd, (char*)frame, 500000);
+    if (frameSize < 0)
+    {
+      printf("read err\n");
+      continue;
+    }
+
+    if (startCode3((char*)frame))
+      startCode = 3;
+    else
+      startCode = 4;
+
+    frameSize -= startCode;
+    rtpSendH264Frame(socket, CLIENT_IP, port,
+      rtpPacket, frame + startCode, frameSize);
+    for (int i = 0; i < 1000; i++) {
+      std::cout << (int)rtpPacket->payload[i] << " ";
+    }
+    std::cout << std::endl;
+    std::cout << std::endl;
+    rtpPacket->rtpHeader.timestamp += 90000 / FPS;
+
+    std::this_thread::sleep_for(std::chrono::milliseconds(1000 / fps));
+  }
+
+  free(rtpPacket);
+  free(frame);
+
+  return 0;
+}