mfc 中ffmpeg yuy2字节流转图片完整代码

以下是将 YUY2 格式的字节流转换为图片的完整 MFC 代码：

#include <iostream>
#include <fstream>
#include "stdafx.h"
extern "C" {
#include <libavcodec/avcodec.h>
#include <libavformat/avformat.h>
#include <libswscale/swscale.h>
}

#define INPUT_FILE_NAME "test.yuy2"
#define OUTPUT_FILE_NAME "test.jpg"
#define WIDTH 640
#define HEIGHT 480

int _tmain(int argc, TCHAR* argv[], TCHAR* envp[])
{
    // 初始化 FFmpeg
    av_register_all();

    // 打开输入文件
    std::ifstream inputFile(INPUT_FILE_NAME, std::ios::binary | std::ios::ate);
    if (!inputFile.is_open()) {
        std::cerr << "Could not open input file: " << INPUT_FILE_NAME << std::endl;
        return -1;
    }
    int inputSize = inputFile.tellg();
    uint8_t *inputData = new uint8_t[inputSize];
    inputFile.seekg(0, std::ios::beg);
    inputFile.read((char*)inputData, inputSize);
    inputFile.close();

    // 创建 AVFrame 和 AVPicture
    AVFrame *pFrame = av_frame_alloc();
    AVPicture picture;
    avpicture_alloc(&picture, AV_PIX_FMT_YUV422P, WIDTH, HEIGHT);

    // 填充 AVFrame
    pFrame->data[0] = inputData;
    pFrame->data[1] = pFrame->data[0] + WIDTH * HEIGHT * 2 / 4;
    pFrame->data[2] = pFrame->data[1];
    pFrame->linesize[0] = WIDTH * 2;
    pFrame->linesize[1] = WIDTH;
    pFrame->linesize[2] = WIDTH;

    // 将 AVFrame 转换为 AVPicture
    struct SwsContext *sws_ctx = sws_getContext(WIDTH, HEIGHT, AV_PIX_FMT_YUYV422, WIDTH, HEIGHT, AV_PIX_FMT_YUV422P, 0, NULL, NULL, NULL);
    sws_scale(sws_ctx, pFrame->data, pFrame->linesize, 0, HEIGHT, picture.data, picture.linesize);

    // 保存为图片
    AVCodec *pCodec = avcodec_find_encoder(AV_CODEC_ID_MJPEG);
    AVCodecContext *pCodecCtx = avcodec_alloc_context3(pCodec);
    pCodecCtx->pix_fmt = AV_PIX_FMT_YUVJ422P;
    pCodecCtx->width = WIDTH;
    pCodecCtx->height = HEIGHT;
    pCodecCtx->time_base.num = 1;
    pCodecCtx->time_base.den = 25;
    avcodec_open2(pCodecCtx, pCodec, NULL);
    AVPacket pkt;
    av_init_packet(&pkt);
    pkt.data = NULL;
    pkt.size = 0;
    int got_packet = 0;
    avcodec_encode_video2(pCodecCtx, &pkt, &picture, &got_packet);
    if (got_packet) {
        FILE *fp = fopen(OUTPUT_FILE_NAME, "wb");
        fwrite(pkt.data, 1, pkt.size, fp);
        fclose(fp);
    }
    avcodec_close(pCodecCtx);
    av_free(pCodecCtx);
    av_free_packet(&pkt);

    // 释放资源
    avpicture_free(&picture);
    av_frame_free(&pFrame);
    sws_freeContext(sws_ctx);
    delete[] inputData;

    return 0;
}

这段代码利用了 C++ 的 ifstream 类读取 YUY2 格式的字节流数据，并将其转换为 JPEG 格式的图片。需要注意的是，这里使用了 FFmpeg 中的 libswscale 库进行图像转换。