cplayer/CPlayer/transcode/Transcode.cpp

#include "Transcode.h"
#include "LHQLogAPI.h"


#if(USING_FFMPEG == true)
extern "C"
{
#include "libavcodec/avcodec.h"
#include "libswscale/swscale.h"
#include "libavutil/pixfmt.h"
#include "libavutil/imgutils.h"
}
#endif  // USING_FFMPEG

TransCode::TransCode()
{

}

TransCode::~TransCode()
{
#if(USING_FFMPEG == true)
    if(m_swsCtx != nullptr)
    {
        sws_freeContext(m_swsCtx);
        m_swsCtx = nullptr;
    }
#endif  // USING_FFMPEG

}

/* 使用ffmpeg将yv12转换成RGB24 */
// bool YV12ToRGB24_FFmpeg(unsigned char *pYV12Data, unsigned char *pRGB24Data, int width, int height)
// {

//     if (width < 1 || height < 1 || pYV12Data == NULL || pRGB24Data == NULL)
//         return false;
//     //int srcNumBytes,dstNumBytes;
//     //uint8_t *pSrc,*pDst;
//     AVPicture pFrameYUV, pFrameBGR;
    
//     //pFrameYUV = avpicture_alloc();
//     //srcNumBytes = avpicture_get_size(PIX_FMT_YUV420P,width,height);
//     //pSrc = (uint8_t *)malloc(sizeof(uint8_t) * srcNumBytes);
//     avpicture_fill(&pFrameYUV, pYV12Data, AV_PIX_FMT_YUV420P, width, height);

//     //U,V互换
//     uint8_t * ptmp=pFrameYUV.data[1];
//     pFrameYUV.data[1]=pFrameYUV.data[2];
//     pFrameYUV.data [2]=ptmp;

//     //pFrameBGR = avcodec_alloc_frame();
//     //dstNumBytes = avpicture_get_size(PIX_FMT_BGR24,width,height);
//     //pDst = (uint8_t *)malloc(sizeof(uint8_t) * dstNumBytes);
//     avpicture_fill(&pFrameBGR, pRGB24Data, AV_PIX_FMT_BGR24, width,height);

//     struct SwsContext* imgCtx = NULL;
//     imgCtx = sws_getContext(width,height, AV_PIX_FMT_YUV420P, width, height, AV_PIX_FMT_BGR24,SWS_BILINEAR, 0, 0, 0);

//     if (imgCtx != NULL){
//         sws_scale(imgCtx,pFrameYUV.data,pFrameYUV.linesize,0,height,pFrameBGR.data,pFrameBGR.linesize);
//         if(imgCtx){
//             sws_freeContext(imgCtx);
//             imgCtx = NULL;
//         }
//         return true;
//     }
//     else{
//         sws_freeContext(imgCtx);
//         imgCtx = NULL;
//         return false;
//     }
// }

#if(USING_FFMPEG == true)
bool TransCode::YV12ToRGB24_FFmpeg(unsigned char *pYV12Data, unsigned char *pRGB24Data, int width, int height)
{
    int ret = 0;
    /* 创建AVFrame */
    AVFrame* pFrameYV12 = av_frame_alloc();
    AVFrame* pFrameBGR = av_frame_alloc();

    /* 将pFrameYV12与pYV12Data相关联 */
    ret = av_image_fill_arrays(pFrameYV12->data, pFrameYV12->linesize, pYV12Data, AV_PIX_FMT_YUV420P, width, height, 1);
    if(ret < 0)
    {
        av_frame_free(&pFrameYV12);
        av_frame_free(&pFrameBGR);
        return false;
    }
    /* UV互换，海康的UV是反的 */
    uint8_t* pTmp = pFrameYV12->data[1];
    pFrameYV12->data[1] = pFrameYV12->data[2];
    pFrameYV12->data[2] = pTmp;

    /* 将pFrameBGR和数组pRGB24Data关联起来 */
    // ret = av_image_fill_arrays(pFrameBGR->data, pFrameBGR->linesize, pRGB24Data, AV_PIX_FMT_BGR24, width, height, 1);
    ret = av_image_fill_arrays(pFrameBGR->data, pFrameBGR->linesize, pRGB24Data, AV_PIX_FMT_RGB24, width, height, 1);
    if(ret < 0)
    {
        av_frame_free(&pFrameYV12);
        av_frame_free(&pFrameBGR);
        return false;
    }

    /* 获取转码上下文 */
    if(m_swsCtx == nullptr)
    {
        m_swsCtx = sws_getCachedContext(m_swsCtx,
                                width, height,                              /* 原图像大小和格式 */
                                AV_PIX_FMT_YUV420P,                         /* 输入图像的像素格式 */
                                width, height,                              /* 目标图像的大小 */
                                AV_PIX_FMT_RGB24,                           /* 目标图像的格式 */
                                SWS_BILINEAR,                               /* 图像缩放算法，双线性 */
                                nullptr,                                    /* 输入图像的滤波器信息，不需要传NULL */
                                nullptr,                                    /* 输出图像的滤波器信息，不需要传NULL */
                                nullptr);                                   /* 特定缩放算法需要的参数，不需要传NULL */
    }
    /* 转换图像 */
    bool result = false;
    if(m_swsCtx != nullptr)
    {
        sws_scale(m_swsCtx, pFrameYV12->data, pFrameYV12->linesize, 0, height, pFrameBGR->data, pFrameBGR->linesize);
        result = true;
    }else {
        LH_WRITE_ERROR(QString("获取转码上下文失败"));
        result = false;
    }
    /* 释放资源 */
    av_frame_free(&pFrameYV12);
    av_frame_free(&pFrameBGR);
    return result;
}

#else
bool TransCode::YV12ToRGB24_FFmpeg(unsigned char *pYV12Data, unsigned char *pRGB24Data, int width, int height)
{
    return false;
}

#endif // USING_FFMPEG



/* YV12转RGB888 */
void TransCode::YV12ToRGB888(unsigned char *pYV12Data, unsigned char *pRGB24Data, int width, int height)
{
    int ySize = width * height;
    int uvSize = ySize / 4;

    const uint8_t* yData = pYV12Data;
    const uint8_t* vData = pYV12Data + ySize;
    const uint8_t* uData = pYV12Data + ySize + uvSize;

    for (int y = 0; y < height; y++) {
        for (int x = 0; x < width; x++) {
            int yIndex = y * width + x;
            int uvIndex = (y / 2) * (width / 2) + (x / 2);

            uint8_t Y = yData[yIndex];
            uint8_t U = uData[uvIndex];
            uint8_t V = vData[uvIndex];

            // YUV 转 RGB
            int R = Y + 1.403 * (V - 128);
            int G = Y - 0.344 * (U - 128) - 0.714 * (V - 128);
            int B = Y + 1.770 * (U - 128);

            // 限制范围 [0, 255]
            R = std::min(std::max(R, 0), 255);
            G = std::min(std::max(G, 0), 255);
            B = std::min(std::max(B, 0), 255);

            // 存储 RGB 数据
            int rgbIndex = yIndex * 3;
            pRGB24Data[rgbIndex]     = static_cast<uint8_t>(R);
            pRGB24Data[rgbIndex + 1] = static_cast<uint8_t>(G);
            pRGB24Data[rgbIndex + 2] = static_cast<uint8_t>(B);
        }
    }
}


/* RGB888转QImage */
void TransCode::YV12ToQImage(unsigned char *pYV12Data, Image_QImage& image, int width, int height)
{
    unsigned char* rgbData = new unsigned char [width * height * 3];

    YV12ToRGB888(pYV12Data, rgbData, width, height);
    if(rgbData != nullptr)
    // if(YV12ToRGB24_FFmpeg(pYV12Data, rgbData, width, height))
    {
        image.image = QImage(rgbData, width, height, QImage::Format_RGB888);
        image.width = width;
        image.height = height;
    }else {
        LH_WRITE_ERROR("YV12ToRGB24_FFmpeg failed!");
    }

    

    /* 释放资源 */
    delete [] rgbData;
}


/* YV12转YUV420 */
void TransCode::YV12ToYUV420(unsigned char *pYV12Data, Image_YUV420& yuvData, int width, int height)
{
    int y_size = width * height;
    int uv_size = y_size / 4;

    // 分配 YUV 数据的空间
    yuvData.yData.resize(y_size);
    yuvData.uData.resize(uv_size);
    yuvData.vData.resize(uv_size);
    yuvData.width = width;
    yuvData.height = height;

    // 提取 Y、V、U 分量，交换uv分量，海康的uv是反的
    const uint8_t* y = pYV12Data;
    const uint8_t* v = pYV12Data + y_size;
    const uint8_t* u = pYV12Data + y_size + uv_size;

    // 复制 Y 分量
    std::memcpy(yuvData.yData.data(), y, y_size);

    // 复制 U 分量
    std::memcpy(yuvData.uData.data(), u, uv_size);

    // 复制 V 分量
    std::memcpy(yuvData.vData.data(), v, uv_size);

}