使用SDL 2.0.20?Simple DirectMedia Layer - SDL version 2.0.20 (stable)https://www.libsdl.org/release/SDL2-devel-2.0.20-VC.zip

參考文章：

ffmpeg tutorial

學習文章的同時基于ffmpeg 4.4 和 sdl 2.0 做同樣功能的mfc demo。

可以先參考：CSDN

在制作播放器時，我們將使用 SDL 來輸出媒體文件的音頻和視頻。 SDL 是一個出色的跨平臺多媒體庫，可用于 MPEG 播放軟件、模擬器和許多視頻游戲。您需要為您的系統下載并安裝 SDL 開發庫，以便編譯本教程中的程序。

所以我們目前的計劃是替換教程 1 中的 SaveFrame() 函數，而是將我們的幀輸出到屏幕上。但首先我們必須先了解如何使用 SDL 庫。首先，我們必須包含庫并初始化 SDL：

參考SDL2源代碼分析1：初始化（SDL_Init()）_雷霄驊(leixiaohua1020)的專欄-CSDN博客_sdl_init

使用SDL 播放一個視頻代碼流程大體如下：

初始化：

1. SDL_Init() 初始化SDL

2. SDL_CreateWindow(): 創建窗口

3. SDL_CreateRenderer() 基于窗口創建渲染器

4. SDL_CreateTexture() 創建紋理

循環渲染數據

SDL_UpdateTexture 設置紋理的數據

SDL_RenderCopy 紋理復制給渲染器

SDL_RenderPresent 顯示

// MFCAudioResampleDlg.cpp: 實現文件 //#include "pch.h" #include "framework.h" #include "MFCAudioResample.h" #include "MFCAudioResampleDlg.h" #include "afxdialogex.h" #include <thread> #include <future>//Refresh Event #define REFRESH_EVENT (SDL_USEREVENT + 1)#define BREAK_EVENT (SDL_USEREVENT + 2)std::string GetFFmpegErorString(int errnum) {static CHAR g_av_error[AV_ERROR_MAX_STRING_SIZE] = { 0 };return std::string(av_make_error_string(g_av_error, AV_ERROR_MAX_STRING_SIZE, errnum)); }void msgBoxFFmpegError(int errnum) {::MessageBoxA(0, 0, GetFFmpegErorString(errnum).c_str(), 0); }std::wstring GetOneFile(BOOL bOpen = TRUE) {CString FilePathName;CFileDialog dlg(bOpen, NULL, NULL, NULL, NULL);//TRUE為OPEN對話框，FALSE為SAVE AS對話框 if (dlg.DoModal() == IDOK) {//清空FilePathName = dlg.GetPathName();}return std::wstring(FilePathName.GetBuffer()); }#ifdef _DEBUG #define new DEBUG_NEW #endif// 用于應用程序“關于”菜單項的 CAboutDlg 對話框class CAboutDlg : public CDialogEx { public:CAboutDlg();// 對話框數據 #ifdef AFX_DESIGN_TIMEenum { IDD = IDD_ABOUTBOX }; #endifprotected:virtual void DoDataExchange(CDataExchange* pDX); // DDX/DDV 支持// 實現 protected:DECLARE_MESSAGE_MAP() };CAboutDlg::CAboutDlg() : CDialogEx(IDD_ABOUTBOX) { }void CAboutDlg::DoDataExchange(CDataExchange* pDX) {CDialogEx::DoDataExchange(pDX); }BEGIN_MESSAGE_MAP(CAboutDlg, CDialogEx) END_MESSAGE_MAP()// CMFCAudioResampleDlg 對話框CMFCAudioResampleDlg::CMFCAudioResampleDlg(CWnd* pParent /*=nullptr*/): CDialogEx(IDD_MFCAUDIORESAMPLE_DIALOG, pParent) {m_hIcon = AfxGetApp()->LoadIcon(IDR_MAINFRAME); }void CMFCAudioResampleDlg::DoDataExchange(CDataExchange* pDX) {CDialogEx::DoDataExchange(pDX);DDX_Control(pDX, IDC_EDIT_INPUT_FILE, m_targetFilePath); }BEGIN_MESSAGE_MAP(CMFCAudioResampleDlg, CDialogEx)ON_WM_SYSCOMMAND()ON_WM_PAINT()ON_WM_QUERYDRAGICON()ON_BN_CLICKED(IDC_BUTTON_CHOOSE_FILE, &CMFCAudioResampleDlg::OnBnClickedButtonChooseFile) END_MESSAGE_MAP()// CMFCAudioResampleDlg 消息處理程序BOOL CMFCAudioResampleDlg::OnInitDialog() {CDialogEx::OnInitDialog();// 將“關于...”菜單項添加到系統菜單中。// IDM_ABOUTBOX 必須在系統命令范圍內。ASSERT((IDM_ABOUTBOX & 0xFFF0) == IDM_ABOUTBOX);ASSERT(IDM_ABOUTBOX < 0xF000);CMenu* pSysMenu = GetSystemMenu(FALSE);if (pSysMenu != nullptr){BOOL bNameValid;CString strAboutMenu;bNameValid = strAboutMenu.LoadString(IDS_ABOUTBOX);ASSERT(bNameValid);if (!strAboutMenu.IsEmpty()){pSysMenu->AppendMenu(MF_SEPARATOR);pSysMenu->AppendMenu(MF_STRING, IDM_ABOUTBOX, strAboutMenu);}}// 設置此對話框的圖標。 當應用程序主窗口不是對話框時，框架將自動// 執行此操作SetIcon(m_hIcon, TRUE); // 設置大圖標SetIcon(m_hIcon, FALSE); // 設置小圖標// TODO: 在此添加額外的初始化代碼return TRUE; // 除非將焦點設置到控件，否則返回 TRUE }void CMFCAudioResampleDlg::OnSysCommand(UINT nID, LPARAM lParam) {if ((nID & 0xFFF0) == IDM_ABOUTBOX){CAboutDlg dlgAbout;dlgAbout.DoModal();}else{CDialogEx::OnSysCommand(nID, lParam);} }// 如果向對話框添加最小化按鈕，則需要下面的代碼 // 來繪制該圖標。 對于使用文檔/視圖模型的 MFC 應用程序， // 這將由框架自動完成。void CMFCAudioResampleDlg::OnPaint() {if (IsIconic()){CPaintDC dc(this); // 用于繪制的設備上下文SendMessage(WM_ICONERASEBKGND, reinterpret_cast<WPARAM>(dc.GetSafeHdc()), 0);// 使圖標在工作區矩形中居中int cxIcon = GetSystemMetrics(SM_CXICON);int cyIcon = GetSystemMetrics(SM_CYICON);CRect rect;GetClientRect(&rect);int x = (rect.Width() - cxIcon + 1) / 2;int y = (rect.Height() - cyIcon + 1) / 2;// 繪制圖標dc.DrawIcon(x, y, m_hIcon);}else{CDialogEx::OnPaint();} }//當用戶拖動最小化窗口時系統調用此函數取得光標 //顯示。 HCURSOR CMFCAudioResampleDlg::OnQueryDragIcon() {return static_cast<HCURSOR>(m_hIcon);} void CMFCAudioResampleDlg::SaveFrame(AVFrame* pFrame, int width, int height, int iFrame) {m_Frame = pFrame;SDL_Event event;event.type = REFRESH_EVENT;SDL_PushEvent(&event);}void CMFCAudioResampleDlg::OnBnClickedButtonChooseFile() {if (!SDL_Init(SDL_INIT_VIDEO | SDL_INIT_TIMER)) {assert(false);}// TODO: 在此添加控件通知處理程序代碼auto target = GetOneFile();m_targetFilePath.SetWindowTextW(target.c_str());UpdateData(TRUE);CString strTargetWindowText;m_targetFilePath.GetWindowTextW(strTargetWindowText);AVFormatContext* avFormatContext = avformat_alloc_context();USES_CONVERSION;if (!PathFileExists(strTargetWindowText.GetBuffer())) {return;}auto result = avformat_open_input(&avFormatContext, W2A((strTargetWindowText.GetBuffer())), nullptr, nullptr);if (result < 0) {assert(false);}result = avformat_find_stream_info(avFormatContext, NULL);if (result < 0){assert(false);}av_dump_format(avFormatContext, 0, NULL, 0);// Find the first video streamint videoStream = -1;for (int i = 0; i < avFormatContext->nb_streams; i++)if (avFormatContext->streams[i]->codecpar->codec_type == AVMEDIA_TYPE_VIDEO) {videoStream = i;break;}if (videoStream == -1)return ; // Didn't find a video streamAVCodecContext* avCodecContext = avcodec_alloc_context3(NULL);result = avcodec_parameters_to_context(avCodecContext, avFormatContext->streams[videoStream]->codecpar);if (result < 0){assert(false);}avCodecContext->pkt_timebase = avFormatContext->streams[videoStream]->time_base;AVCodec* codec = avcodec_find_decoder(avCodecContext->codec_id);avCodecContext->codec_id = codec->id;result = avcodec_open2(avCodecContext, codec, nullptr);if (result < 0){msgBoxFFmpegError(result);assert(false);}m_sdlThread = std::move(std::thread([this, avCodecContext]() {m_sdlWindow = SDL_CreateWindow("sdl display", SDL_WINDOWPOS_UNDEFINED, SDL_WINDOWPOS_UNDEFINED, avCodecContext->width, avCodecContext->height, SDL_WINDOW_OPENGL);assert(m_sdlWindow);m_sdlRender = SDL_CreateRenderer(m_sdlWindow, -1, 0);assert(m_sdlRender);m_sdlTexture = SDL_CreateTexture(m_sdlRender, SDL_PixelFormatEnum::SDL_PIXELFORMAT_RGB24, SDL_TextureAccess::SDL_TEXTUREACCESS_STREAMING, avCodecContext->width, avCodecContext->height);assert(m_sdlTexture);SDL_Event event;while (1){SDL_WaitEvent(&event);if (event.type == REFRESH_EVENT) {SDL_UpdateTexture(m_sdlTexture, nullptr, m_Frame->data[0], avCodecContext->width * 3);SDL_Rect sdlRect = {};sdlRect.x = 0;sdlRect.y = 0;sdlRect.h = avCodecContext->height;sdlRect.w = avCodecContext->width;SDL_RenderClear(m_sdlRender);SDL_RenderCopy(m_sdlRender, m_sdlTexture, nullptr, &sdlRect);SDL_RenderPresent(m_sdlRender);}else if (event.type == SDL_WINDOWEVENT) {}else if (event.type == SDL_QUIT) {}else if (event.type == BREAK_EVENT) {break;}}}));AVFrame* pFrame = nullptr;pFrame = av_frame_alloc();// 我們最終的目的是將原始視頻幀存儲為24-bit RGB 視頻。AVFrame* pFrameRGB24 = av_frame_alloc();uint8_t* bufferRawRGB24 = nullptr;const int numBytes = av_image_get_buffer_size(AV_PIX_FMT_RGB24, avCodecContext->width, avCodecContext->height, 1);bufferRawRGB24 = (uint8_t*)av_malloc(numBytes * sizeof(uint8_t));av_image_fill_arrays(pFrameRGB24->data, pFrameRGB24->linesize, bufferRawRGB24, AV_PIX_FMT_RGB24, avCodecContext->width, avCodecContext->height, 1);// 讀取數據// sws_ctx 定義了從pix_fmt 到 AV_PIX_FMT_RGB24的轉換struct SwsContext* sws_ctx = NULL;int frameFinished;// initialize SWS context for software scalingsws_ctx = sws_getContext(avCodecContext->width,avCodecContext->height,avCodecContext->pix_fmt,avCodecContext->width,avCodecContext->height,AV_PIX_FMT_RGB24,SWS_BILINEAR,NULL,NULL,NULL);int i = 0;AVPacket packet;bool bReadEof = false;while (true){Sleep(33);int readResult = -1;if (!bReadEof){readResult = av_read_frame(avFormatContext, &packet);if (readResult < 0) {::MessageBoxA(0, 0, GetFFmpegErorString(readResult).c_str(), 0);bReadEof = true;}else if (readResult == 0) {static int iCnt = 0;if (packet.stream_index == videoStream) {++iCnt;}CString str;str.Format(L"cunt[%d]\r\n", iCnt);OutputDebugStringW(str.GetBuffer());}}if (bReadEof){// 需要給刷空avcodec_send_packet(avCodecContext, NULL);}else{// Is this a packet from the video stream?if (packet.stream_index == videoStream) {// Decode video frameavcodec_send_packet(avCodecContext, &packet);}}int receiveResult = avcodec_receive_frame(avCodecContext, pFrame);// Did we get a video frame?if (receiveResult == 0) {// Convert the image from its native format to RGBsws_scale(sws_ctx, (uint8_t const* const*)pFrame->data,pFrame->linesize, 0, avCodecContext->height,pFrameRGB24->data, pFrameRGB24->linesize);++i;SaveFrame(pFrameRGB24, avCodecContext->width,avCodecContext->height, i);}else if (receiveResult == AVERROR_EOF){::MessageBoxA(0, 0, "read eof", 0);SDL_Event event;event.type = BREAK_EVENT;SDL_PushEvent(&event);break;}else if(receiveResult == AVERROR(EAGAIN)){if (bReadEof) {break;}else {}}else {msgBoxFFmpegError(receiveResult);}// Free the packet that was allocated by av_read_frameif(readResult == 0)av_packet_unref(&packet);}SDL_Quit();av_frame_free(&pFrame);av_frame_free(&pFrameRGB24);av_free(bufferRawRGB24);avcodec_close(avCodecContext);avformat_close_input(&avFormatContext); }

完整項目ffmpegsdl2.0rgb24player-互聯網文檔類資源-CSDN下載

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