輸出ppm檔案有誤,無法顯示
阿新 • • 發佈:2021-02-05
// FFmpegDemo1.cpp : 此檔案包含 "main" 函式。程式執行將在此處開始並結束。 // #include<iostream> #include<output> using namespace xiuye; extern "C" { #include <libavcodec/avcodec.h> #include <libavformat/avformat.h> //#include <ffmpeg/swscale.h> #include <libswscale/swscale.h> #include <libavutil/imgutils.h> } //儲存的ppm檔案 無法顯示!!! void SaveFrame(AVFrame* pFrame, int width, int height, int iFrame) { FILE* pFile; char szFilename[32]; int y; // Open file sprintf_s(szFilename, "frame%d.ppm", iFrame); fopen_s(&pFile,szFilename, "wb"); if (pFile == NULL) return; // Write header fprintf(pFile, "P6\n%d %d\n255\n", width, height); // Write pixel data for (y = 0; y < height; y++) fwrite(pFrame->data[0] + y * pFrame->linesize[0], 1, width * 3, pFile); // Close file fclose(pFile); } int main(int argc, char* argv[]) { //新的ffmpeg庫不需要集中初始化的組建 //::av_register_all(); AVFormatContext* pFormatCtx = NULL; //檔案工作路徑是專案路徑 並不是輸出debug 或者 release的路徑OK!!! if (avformat_open_input(&pFormatCtx, "D:/codes/windows/FFmpegDemo1/x64/Release/888.mp4", nullptr, nullptr) != 0) { std::cout << "failed to open input" << std::endl; return -1; } if (avformat_find_stream_info(pFormatCtx, nullptr) < 0) { std::cout << "failed to find stream info" << std::endl; return -2; } //if (argc < 2) { // println("input parameters less than 2"); // return -1; //} println(argv[0]); //log(argv[1]); // Dump information about file onto standard error av_dump_format(pFormatCtx, 0, argv[1], 0); int i; AVCodecContext* pCodecCtxOrig = NULL; AVCodecParameters* pCodecCtx = NULL; // Find the first video stream int videoStream = -1; for (i = 0; i < pFormatCtx->nb_streams; i++) if (pFormatCtx->streams[i]->codecpar->codec_type == AVMEDIA_TYPE_VIDEO) { videoStream = i; break; } if (videoStream == -1) return -1; // Didn't find a video stream // Get a pointer to the codec context for the video stream pCodecCtx = pFormatCtx->streams[videoStream]->codecpar; AVCodec* pCodec = NULL; // Find the decoder for the video stream pCodec = avcodec_find_decoder(pCodecCtx->codec_id); if (pCodec == NULL) { fprintf(stderr, "Unsupported codec!\n"); return -1; // Codec not found } // Copy context AVCodecContext* pCodecCtx2 = avcodec_alloc_context3(pCodec); //if (avcodec_copy_context(pCodecCtx, pCodecCtxOrig) != 0) { //if (avcodec_parameters_to_context(pCodecCtxOrig,pCodecCtx) != 0) {//這一句有問題,原因待查! // fprintf(stderr, "Couldn't copy codec context"); // return -1; // Error copying codec context //} // Open codec if (avcodec_open2(pCodecCtx2, pCodec,nullptr) < 0) return -1; // Could not open codec AVFrame* pFrame = NULL; // Allocate video frame pFrame = av_frame_alloc(); // Allocate an AVFrame structure AVFrame* pFrameRGB = av_frame_alloc(); if (pFrameRGB == NULL) return -1; uint8_t* buffer = NULL; int numBytes; // Determine required buffer size and allocate buffer //numBytes = avpicture_get_size(AV_PIX_FMT_RGB24, pCodecCtx->width, numBytes = av_image_get_buffer_size(AV_PIX_FMT_RGB24, pCodecCtx->width,pCodecCtx->height,1); buffer = (uint8_t*)av_malloc(numBytes * sizeof(uint8_t)); // Assign appropriate parts of buffer to image planes in pFrameRGB // Note that pFrameRGB is an AVFrame, but AVFrame is a superset // of AVPicture /* avpicture_fill((AVPicture*)pFrameRGB, buffer, AV_PIX_FMT_RGB24, pCodecCtx->width, pCodecCtx->height);*/ av_image_fill_arrays( pFrameRGB->data, pFrameRGB->linesize, buffer, AV_PIX_FMT_RGB24, pCodecCtx->width, pCodecCtx->height, 1); struct SwsContext* sws_ctx = NULL; int frameFinished; AVPacket packet; // initialize SWS context for software scaling sws_ctx = sws_getContext(pCodecCtx->width, pCodecCtx->height, AVPixelFormat(pCodecCtx->format), pCodecCtx->width, pCodecCtx->height, AV_PIX_FMT_RGB24, SWS_BILINEAR, NULL, NULL, NULL ); i = 0; while (av_read_frame(pFormatCtx, &packet) >= 0) { // Is this a packet from the video stream? if (packet.stream_index == videoStream) { // Decode video frame //avcodec_decode_video2(pCodecCtx, pFrame, &frameFinished, &packet); frameFinished = av_read_frame(pFormatCtx, &packet); // Did we get a video frame? if (!frameFinished) { // Convert the image from its native format to RGB sws_scale(sws_ctx, (uint8_t const* const*)pFrame->data, pFrame->linesize, 0, pCodecCtx->height, pFrameRGB->data, pFrameRGB->linesize); // Save the frame to disk if (++i <= 5) SaveFrame(pFrameRGB, pCodecCtx->width, pCodecCtx->height, i); } } // Free the packet that was allocated by av_read_frame //av_free_packet(&packet);//old av_packet_unref(&packet); } // Free the RGB image av_free(buffer); av_free(pFrameRGB); // Free the YUV frame av_free(pFrame); // Close the codecs //av_free(pCodecCtx); //avcodec_close(pCodecCtx); avcodec_close(pCodecCtxOrig); // Close the video file avformat_close_input(&pFormatCtx); std::cout << "Hello World!\n"; } // 執行程式: Ctrl + F5 或除錯 >“開始執行(不除錯)”選單 // 除錯程式: F5 或除錯 >“開始除錯”選單 // 入門使用技巧: // 1. 使用解決方案資源管理器視窗新增/管理檔案 // 2. 使用團隊資源管理器視窗連線到原始碼管理 // 3. 使用輸出視窗檢視生成輸出和其他訊息 // 4. 使用錯誤列表視窗檢視錯誤 // 5. 轉到“專案”>“新增新項”以建立新的程式碼檔案,或轉到“專案”>“新增現有項”以將現有程式碼檔案新增到專案 // 6. 將來,若要再次開啟此專案,請轉到“檔案”>“開啟”>“專案”並選擇 .sln 檔案