x265 create方法

 多线程处理：https://blog.youkuaiyun.com/strikedragon/article/details/82776001

bool allowPools = !p->numaPools || strcmp(p->numaPools, "none");

    // Trim the thread pool if --wpp, --pme, and --pmode are disabled
    if (!p->bEnableWavefront && !p->bDistributeModeAnalysis && !p->bDistributeMotionEstimation && !p->lookaheadSlices)
        allowPools = false;

bDistributeModeAnalysis ：评估使用多线程CU mode的花费

bDistributeMotionEstimation：使用多线程Motion estimation的花费

lookaheadSlices：使用多线程计算每一帧的花费

    m_numPools = 0;
    if (allowPools)
        m_threadPool = ThreadPool::allocThreadPools(p, m_numPools, 0);
    else
    {
        if (!p->frameNumThreads)
        {
            // auto-detect frame threads
            int cpuCount = ThreadPool::getCpuCount();
            ThreadPool::getFrameThreadsCount(p, cpuCount);
        }
    }

并发编码帧的数量

    if (!m_numPools)
    {
        // issue warnings if any of these features were requested
        if (p->bEnableWavefront)
            x265_log(p, X265_LOG_WARNING, "No thread pool allocated, --wpp disabled\n");
        if (p->bDistributeMotionEstimation)
            x265_log(p, X265_LOG_WARNING, "No thread pool allocated, --pme disabled\n");
        if (p->bDistributeModeAnalysis)
            x265_log(p, X265_LOG_WARNING, "No thread pool allocated, --pmode disabled\n");
        if (p->lookaheadSlices)
            x265_log(p, X265_LOG_WARNING, "No thread pool allocated, --lookahead-slices disabled\n");

        // disable all pool features if the thread pool is disabled or unusable.
        p->bEnableWavefront = p->bDistributeModeAnalysis = p->bDistributeMotionEstimation = p->lookaheadSlices = 0;
    }

对于每一个frame的线程，创建frameEncoder

 for (int i = 0; i < m_param->frameNumThreads; i++)
    {
        m_frameEncoder[i] = new FrameEncoder;
        m_frameEncoder[i]->m_nalList.m_annexB = !!m_param->bAnnexB;
    }

 

if (m_numPools)
    {
        for (int i = 0; i < m_param->frameNumThreads; i++)
        {
            int pool = i % m_numPools;
            m_frameEncoder[i]->m_pool = &m_threadPool[pool];
            m_frameEncoder[i]->m_jpId = m_threadPool[pool].m_numProviders++;
            m_threadPool[pool].m_jpTable[m_frameEncoder[i]->m_jpId] = m_frameEncoder[i];

把每个frameEncoder分配到对应的pool中，JobProvider是Frame level job providers. FrameEncoder and Lookahead derive from this class and implement findJob()

        }
        for (int i = 0; i < m_numPools; i++)
            m_threadPool[i].start();
    }
    else
    {
        /* CU stats and noise-reduction buffers are indexed by jpId, so it cannot be left as -1 */
        for (int i = 0; i < m_param->frameNumThreads; i++)
            m_frameEncoder[i]->m_jpId = 0;
    }

创建或者解析ScalingList

if (!m_scalingList.init())
    {
        x265_log(m_param, X265_LOG_ERROR, "Unable to allocate scaling list arrays\n");
        m_aborted = true;
        return;
    }
    else if (!m_param->scalingLists || !strcmp(m_param->scalingLists, "off"))
        m_scalingList.m_bEnabled = false;
    else if (!strcmp(m_param->scalingLists, "default"))
        m_scalingList.setDefaultScalingList();
    else if (m_scalingList.parseScalingList(m_param->scalingLists))
        m_aborted = true;

根据Pool来计算lookahead的线程，Lookahead

int pools = m_numPools;
    ThreadPool* lookAheadThreadPool = 0;
    if (m_param->lookaheadThreads > 0)
    {
        lookAheadThreadPool = ThreadPool::allocThreadPools(p, pools, 1);
    }
    else
        lookAheadThreadPool = m_threadPool;
    m_lookahead = new Lookahead(m_param, lookAheadThreadPool);
    if (pools)
    {
        m_lookahead->m_jpId = lookAheadThreadPool[0].m_numProviders++;
        lookAheadThreadPool[0].m_jpTable[m_lookahead->m_jpId] = m_lookahead;
    }
    if (m_param->lookaheadThreads > 0)
        for (int i = 0; i < pools; i++)
            lookAheadThreadPool[i].start();

创建DPB和RateControl类

    m_dpb = new DPB(m_param);
    m_rateControl = new RateControl(*m_param);

初始化VPS，SPS和PPS

initVPS(&m_vps);
    initSPS(&m_sps);
    initPPS(&m_pps);