ffmepg6.0录屏推流c++示例

以下是在 Windows 平台上，使用 FFmpeg 6.0 实现录屏推流的 C++ 示例代码：

#include <iostream>
#include <Windows.h>
#include <d3d9.h>
#include <d3dx9.h>
#include <libavcodec/avcodec.h>
#include <libavformat/avformat.h>
#include <libavutil/opt.h>

#pragma comment(lib, "d3d9.lib")
#pragma comment(lib, "d3dx9.lib")
#pragma comment(lib, "avcodec.lib")
#pragma comment(lib, "avformat.lib")
#pragma comment(lib, "avutil.lib")

#define SCREEN_WIDTH 1920
#define SCREEN_HEIGHT 1080
#define FPS 30
#define BIT_RATE 4000000
#define STREAM_URL "rtmp://localhost/live/stream"

int main()
{
    // 初始化 D3D9
    IDirect3D9Ex* pD3D = nullptr;
    if (FAILED(Direct3DCreate9Ex(D3D_SDK_VERSION, &pD3D)))
    {
        std::cerr << "Failed to create IDirect3D9Ex object" << std::endl;
        return -1;
    }

    // 枚举显示器适配器
    UINT adapterCount = pD3D->GetAdapterCount();
    if (adapterCount == 0)
    {
        std::cerr << "No display adapter found" << std::endl;
        return -1;
    }

    // 获取第一个适配器的显示模式
    D3DDISPLAYMODE displayMode;
    if (FAILED(pD3D->EnumAdapterModes(0, D3DFMT_X8R8G8B8, 0, &displayMode)))
    {
        std::cerr << "Failed to enumerate display adapter modes" << std::endl;
        return -1;
    }

    // 创建 D3D 设备
    D3DPRESENT_PARAMETERS d3dpp = {};
    d3dpp.Windowed = TRUE;
    d3dpp.BackBufferFormat = D3DFMT_X8R8G8B8;
    d3dpp.BackBufferWidth = SCREEN_WIDTH;
    d3dpp.BackBufferHeight = SCREEN_HEIGHT;
    d3dpp.SwapEffect = D3DSWAPEFFECT_DISCARD;
    IDirect3DDevice9Ex* pD3DDevice = nullptr;
    if (FAILED(pD3D->CreateDeviceEx(
        D3DADAPTER_DEFAULT,
        D3DDEVTYPE_HAL,
        GetDesktopWindow(),
        D3DCREATE_HARDWARE_VERTEXPROCESSING,
        &d3dpp,
        nullptr,
        &pD3DDevice)))
    {
        std::cerr << "Failed to create IDirect3DDevice9Ex object" << std::endl;
        return -1;
    }

    // 初始化 FFmpeg
    av_register_all();
    avcodec_register_all();
    avformat_network_init();

    // 创建输出流
    AVFormatContext* pFormatCtx = nullptr;
    if (avformat_alloc_output_context2(&pFormatCtx, nullptr, "flv", STREAM_URL) < 0)
    {
        std::cerr << "Failed to allocate output context" << std::endl;
        return -1;
    }

    // 创建视频流
    AVCodec* pCodec = nullptr;
    AVStream* pStream = avformat_new_stream(pFormatCtx, pCodec);
    if (!pStream)
    {
        std::cerr << "Failed to allocate video stream" << std::endl;
        return -1;
    }

    // 设置编码器参数
    AVCodecContext* pCodecCtx = pStream->codec;
    pCodecCtx->codec_id = AV_CODEC_ID_H264;
    pCodecCtx->codec_type = AVMEDIA_TYPE_VIDEO;
    pCodecCtx->width = SCREEN_WIDTH;
    pCodecCtx->height = SCREEN_HEIGHT;
    pCodecCtx->pix_fmt = AV_PIX_FMT_YUV420P;
    pCodecCtx->bit_rate = BIT_RATE;
    pCodecCtx->gop_size = FPS;
    pCodecCtx->time_base = { 1, FPS };
    pCodecCtx->level = 31;
    pCodecCtx->profile = FF_PROFILE_H264_MAIN;
    av_opt_set(pCodecCtx->priv_data, "preset", "ultrafast", 0);
    av_opt_set(pCodecCtx->priv_data, "tune", "zerolatency", 0);

    // 打开编码器
    pCodec = avcodec_find_encoder(pCodecCtx->codec_id);
    if (!pCodec)
    {
        std::cerr << "Failed to find video encoder" << std::endl;
        return -1;
    }
    if (avcodec_open2(pCodecCtx, pCodec, nullptr) < 0)
    {
        std::cerr << "Failed to open video encoder" << std::endl;
        return -1;
    }

    // 打开输出流
    if (avio_open(&pFormatCtx->pb, STREAM_URL, AVIO_FLAG_WRITE) < 0)
    {
        std::cerr << "Failed to open output stream" << std::endl;
        return -1;
    }

    // 写入文件头
    if (avformat_write_header(pFormatCtx, nullptr) < 0)
    {
        std::cerr << "Failed to write file header" << std::endl;
        return -1;
    }

    // 创建缓冲区
    const auto buffer_size = av_image_get_buffer_size(pCodecCtx->pix_fmt, SCREEN_WIDTH, SCREEN_HEIGHT, 1);
    auto buffer = static_cast<uint8_t*>(av_malloc(buffer_size));
    AVFrame* pFrame = av_frame_alloc();
    if (!pFrame)
    {
        std::cerr << "Failed to allocate video frame" << std::endl;
        return -1;
    }
    av_image_fill_arrays(pFrame->data, pFrame->linesize, buffer, pCodecCtx->pix_fmt, SCREEN_WIDTH, SCREEN_HEIGHT, 1);

    // 设置 D3D 设备参数
    IDirect3DSurface9* pSurface = nullptr;
    D3DXMATRIX matrix;
    D3DLOCKED_RECT lockedRect;
    pD3DDevice->CreateOffscreenPlainSurface(SCREEN_WIDTH, SCREEN_HEIGHT, D3DFMT_A8R8G8B8, D3DPOOL_SYSTEMMEM, &pSurface, nullptr);
    D3DXMatrixIdentity(&matrix);

    // 循环推流
    bool running = true;
    while (running)
    {
        // 从 D3D 设备中读取屏幕数据
        if (SUCCEEDED(pD3DDevice->GetFrontBufferData(0, pSurface)))
        {
            if (SUCCEEDED(pSurface->LockRect(&lockedRect, nullptr, D3DLOCK_READONLY)))
            {
                // 将屏幕数据转换为 YUV420P 格式
                for (int y = 0; y < SCREEN_HEIGHT; y++)
                {
                    auto dest = buffer + y * pFrame->linesize[0];
                    auto src = static_cast<uint8_t*>(lockedRect.pBits) + y * lockedRect.Pitch;
                    memcpy(dest, src, SCREEN_WIDTH * 4);
                }
                av_frame_set_pts(pFrame, av_rescale_q(av_gettime(), { 1, AV_TIME_BASE }, pCodecCtx->time_base));

                // 编码并写入数据
                AVPacket packet;
                av_init_packet(&packet);
                packet.data = nullptr;
                packet.size = 0;
                int result = avcodec_send_frame(pCodecCtx, pFrame);
                if (result == 0)
                {
                    while (result >= 0)
                    {
                        result = avcodec_receive_packet(pCodecCtx, &packet);
                        if (result == 0)
                        {
                            packet.stream_index = pStream->index;
                            av_interleaved_write_frame(pFormatCtx, &packet);
                            av_packet_unref(&packet);
                        }
                        else if (result == AVERROR(EAGAIN) || result == AVERROR_EOF)
                        {
                            break;
                        }
                        else
                        {
                            std::cerr << "Failed to encode video frame" << std::endl;
                            running = false;
                        }
                    }
                }
                else
                {
                    std::cerr << "Failed to send video frame for encoding" << std::endl;
                    running = false;
                }

                pSurface->UnlockRect();
            }
        }

        // 限制帧率
        Sleep(1000 / FPS);
    }

    // 写入文件尾
    av_write_trailer(pFormatCtx);

    // 释放资源
    if (pSurface)
    {
        pSurface->Release();
    }
    if (pD3DDevice)
    {
        pD3DDevice->Release();
    }
    if (pD3D)
    {
        pD3D->Release();
    }
    if (pCodecCtx)
    {
        avcodec_close(pCodecCtx);
    }
    if (pFrame)
    {
        av_frame_free(&pFrame);
    }
    if (pFormatCtx)
    {
        avio_close(pFormatCtx->pb);
        avformat_free_context(pFormatCtx);
    }
    if (buffer)
    {
        av_free(buffer);
    }

    return 0;
}

在这个示例中，我们使用了 Windows 平台上的 DirectX 9 API 来捕获屏幕数据，然后使用 FFmpeg 6.0 的编码器将数据编码为 H.264 格式，并通过 RTMP 协议推流到本地的流服务器。您需要根据具体的情况修改 STREAM_URL、SCREEN_WIDTH、SCREEN_HEIGHT、FPS 和 BIT_RATE 等参数。