x265探索与研究（六）：main()函数

x265探索与研究（六）：main()函数

x265源代码的入口函数是main()，本文分析main()的主要功能。

首先给出main()函数的功能及其代码结构；其次给出main()函数源代码以及分析；最后给出main()函数中的主要功能函数的详细功能。

1、main()函数的功能及其代码结构

main()函数的主要功能是解析參数并进行编码的一些准备工作，调用了例如以下几个重要的函数：

（1）cliopt.parse()函数：解析參数

（2）api->encoder_open()函数：打开编码器配置

（3）api->encoder_headers()函数：设置NAL相关信息

（4）api->encoder_encode()函数：进入编码函数

（5）api->encoder_close()函数：结束编码并进行总结

注：encoder_open()函数、encoder_headers()函数、encoder_encode()函数与encoder_close()函数均位于api.app中。

相应的函数关系图例如以下图所看到的：

2、main()函数源代码以及分析

main()函数的源代码分析例如以下代码中的凝视。代码例如以下：

/*=============================================================*/
/*
 ====== Analysed by: RuiDong Fang
 ====== Csdn Blog:	 http://blog.csdn.net/frd2009041510
 ====== Date:		 2016.04.10
 ====== Funtion：	 x265的入口main()函数
 */
/*=============================================================*/
/* CLI return codes:
 *
 * 0 - encode successful
 * 1 - unable to parse command line
 * 2 - unable to open encoder
 * 3 - unable to generate stream headers
 * 4 - encoder abort
 * 5 - unable to open csv file
 *
 */
int main(int argc, char **argv)	//主函数入口
{
#if HAVE_VLD
    // This uses Microsoft's proprietary WCHAR type, but this only builds on Windows to start with
    VLDSetReportOptions(VLD_OPT_REPORT_TO_DEBUGGER | VLD_OPT_REPORT_TO_FILE, L"x265_leaks.txt");
#endif
    PROFILE_INIT();
    THREAD_NAME("API", 0);

    GetConsoleTitle(orgConsoleTitle, CONSOLE_TITLE_SIZE);	//获取控制台窗体
    SetThreadExecutionState(ES_CONTINUOUS | ES_SYSTEM_REQUIRED | ES_AWAYMODE_REQUIRED);

    ReconPlay* reconPlay = NULL;
    CLIOptions cliopt;

    if (cliopt.parse(argc, argv))	//==========分析參数。对编码器的參数进行设定，打开文件
    {
        cliopt.destroy();
        if (cliopt.api)
            cliopt.api->param_free(cliopt.param);
        exit(1);
    }

    x265_param* param = cliopt.param;
    const x265_api* api = cliopt.api;

    /* This allows muxers to modify bitstream format */
    cliopt.output->setParam(param);

    if (cliopt.reconPlayCmd)
        reconPlay = new ReconPlay(cliopt.reconPlayCmd, *param);

    /* note: we could try to acquire a different libx265 API here based on
     * the profile found during option parsing, but it must be done before
     * opening an encoder */

    x265_encoder *encoder = api->encoder_open(param);	//==========encoder_open()函数，打印编码器配置
    if (!encoder)	//若打不开编码器配置。提示错误
    {
        x265_log(param, X265_LOG_ERROR, "failed to open encoder\n");
        cliopt.destroy();
        api->param_free(param);
        api->cleanup();
        exit(2);
    }

    /* get the encoder parameters post-initialization */
    api->encoder_parameters(encoder, param);

    if (cliopt.csvfn)
    {
        cliopt.csvfpt = x265_csvlog_open(*api, *param, cliopt.csvfn, cliopt.csvLogLevel);
        if (!cliopt.csvfpt)
        {
            x265_log(param, X265_LOG_ERROR, "Unable to open CSV log file <%s>, aborting\n", cliopt.csvfn);
            cliopt.destroy();
            if (cliopt.api)
                cliopt.api->param_free(cliopt.param);
            exit(5);
        }
    }

    /* Control-C handler */
	//当键入Ctrl-C的时候，当前运行程序调用指针函数sigint_handler 运行完后，再返回原来运行的地方接着往下走。

if (signal(SIGINT, sigint_handler) == SIG_ERR)
        x265_log(param, X265_LOG_ERROR, "Unable to register CTRL+C handler: %s\n", strerror(errno));

    x265_picture pic_orig, pic_out;		//定义x265的输入pic_orig和输出pic_out
    x265_picture *pic_in = &pic_orig;	//获取x265的输入pic_orig的地址

	/* Allocate recon picture if analysisMode is enabled */
    std::priority_queue<int64_t>* pts_queue = cliopt.output->needPTS() ? new std::priority_queue<int64_t>() : NULL;
    x265_picture *pic_recon = (cliopt.recon || !!param->analysisMode || pts_queue || reconPlay || cliopt.csvLogLevel) ?

&pic_out : NULL;

	uint32_t inFrameCount = 0;	//输入的帧数
    uint32_t outFrameCount = 0;	//输出的帧数

	x265_nal *p_nal;
    x265_stats stats;
    uint32_t nal;
    int16_t *errorBuf = NULL;
    int ret = 0;

    if (!param->bRepeatHeaders)
    {
        if (api->encoder_headers(encoder, &p_nal, &nal) < 0)	//==========encoder_headers函数
        {
            x265_log(param, X265_LOG_ERROR, "Failure generating stream headers\n");
            ret = 3;
            goto fail;
        }
        else
            cliopt.totalbytes += cliopt.output->writeHeaders(p_nal, nal);
    }

    api->picture_init(param, pic_in);

    if (cliopt.bDither)
    {
        errorBuf = X265_MALLOC(int16_t, param->sourceWidth + 1);
        if (errorBuf)
            memset(errorBuf, 0, (param->sourceWidth + 1) * sizeof(int16_t));
        else
            cliopt.bDither = false;
    }

    // main encoder loop（编码主循环）
    while (pic_in && !b_ctrl_c)
    {
        pic_orig.poc = inFrameCount;
        if (cliopt.qpfile)
        {
            if (!cliopt.parseQPFile(pic_orig))
            {
                x265_log(NULL, X265_LOG_ERROR, "can't parse qpfile for frame %d\n", pic_in->poc);
                fclose(cliopt.qpfile);
                cliopt.qpfile = NULL;
            }
        }

		//当输入帧将要所有编码且输入的帧数大于或等于将要编码的帧数
        if (cliopt.framesToBeEncoded && inFrameCount >= cliopt.framesToBeEncoded)
            pic_in = NULL;
        else if (cliopt.input->readPicture(pic_orig))	//每读入一帧
            inFrameCount++;	//输入的帧数自加1
        else
            pic_in = NULL;

        if (pic_in)
        {
            if (pic_in->bitDepth > param->internalBitDepth && cliopt.bDither)
            {
                x265_dither_image(*api, *pic_in, cliopt.input->getWidth(), cliopt.input->getHeight(), errorBuf, param->internalBitDepth);
                pic_in->bitDepth = param->internalBitDepth;
            }
            /* Overwrite PTS */
            pic_in->pts = pic_in->poc;
        }
		//进行编码的入口函数，读入24帧后才開始编码
        int numEncoded = api->encoder_encode(encoder, &p_nal, &nal, pic_in, pic_recon);	//==========encoder_encode()函数。numEncoded是将要编码的帧数
        if (numEncoded < 0)
        {
            b_ctrl_c = 1;
            ret = 4;
            break;
        }

        if (reconPlay && numEncoded)
            reconPlay->writePicture(*pic_recon);

        outFrameCount += numEncoded;

        if (numEncoded && pic_recon && cliopt.recon)
            cliopt.recon->writePicture(pic_out);
        if (nal)
        {
            cliopt.totalbytes += cliopt.output->writeFrame(p_nal, nal, pic_out);
            if (pts_queue)
            {
                pts_queue->push(-pic_out.pts);
                if (pts_queue->size() > 2)
                    pts_queue->pop();
            }
        }

        cliopt.printStatus(outFrameCount); //打印编码帧的详细信息
        if (numEncoded && cliopt.csvLogLevel)
            x265_csvlog_frame(cliopt.csvfpt, *param, *pic_recon, cliopt.csvLogLevel);
    }

    /* Flush the encoder */
	/*功能：前面读入24帧后才開始编码，此处事实上就是处理相应的倒数的24帧，将其存储*/
    while (!b_ctrl_c)	//退出上一个大循环后且没有按下Ctrl+C，代码继续运行
    {
        //==========encoder_encode()函数
		int numEncoded = api->encoder_encode(encoder, &p_nal, &nal, NULL, pic_recon);
        if (numEncoded < 0)
        {
            ret = 4;
            break;
        }

        if (reconPlay && numEncoded)
            reconPlay->writePicture(*pic_recon);

        outFrameCount += numEncoded;
        if (numEncoded && pic_recon && cliopt.recon)
            cliopt.recon->writePicture(pic_out);
        if (nal)
        {
            cliopt.totalbytes += cliopt.output->writeFrame(p_nal, nal, pic_out);
            if (pts_queue)
            {
                pts_queue->push(-pic_out.pts);
                if (pts_queue->size() > 2)
                    pts_queue->pop();
            }
        }

        cliopt.printStatus(outFrameCount);
        if (numEncoded && cliopt.csvLogLevel)
            x265_csvlog_frame(cliopt.csvfpt, *param, *pic_recon, cliopt.csvLogLevel);

        if (!numEncoded)
            break;
    }

    /* clear progress report */
    if (cliopt.bProgress)
        fprintf(stderr, "%*s\r", 80, " ");

fail:

    delete reconPlay;

    api->encoder_get_stats(encoder, &stats, sizeof(stats));
    if (cliopt.csvfpt && !b_ctrl_c)
        x265_csvlog_encode(cliopt.csvfpt, *api, *param, stats, cliopt.csvLogLevel, argc, argv);
    api->encoder_close(encoder);	//==========encoder_close()函数

    int64_t second_largest_pts = 0;
    int64_t largest_pts = 0;
    if (pts_queue && pts_queue->size() >= 2)
    {
        second_largest_pts = -pts_queue->top();
        pts_queue->pop();
        largest_pts = -pts_queue->top();
        pts_queue->pop();
        delete pts_queue;
        pts_queue = NULL;
    }
    cliopt.output->closeFile(largest_pts, second_largest_pts);

    if (b_ctrl_c)	//按下Ctrl+C，直接退出
        general_log(param, NULL, X265_LOG_INFO, "aborted at input frame %d, output frame %d\n",
                    cliopt.seek + inFrameCount, stats.encodedPictureCount);

    api->cleanup(); /* Free library singletons */

    cliopt.destroy();

    api->param_free(param);

    X265_FREE(errorBuf);

    SetConsoleTitle(orgConsoleTitle);	//设置控制窗体标题
    SetThreadExecutionState(ES_CONTINUOUS);

#if HAVE_VLD
    assert(VLDReportLeaks() == 0);
#endif

    return ret;
}

3、main()函数中的部分功能函数的详细功能

3.1、GetConsoleTitle(orgConsoleTitle, CONSOLE_TITLE_SIZE);

GetConsoleTitle的主要功能是获取控制台窗体。当中orgConsoleTitle指向一个缓冲区指针以接收包括标题的字符串。CONSOLE_TITLE_SIZE)是由orgConsoleTitle指向的缓冲区大小。假设函数成功。则返回值是以字符为单位的长度控制台窗体的标题；假设该函数失败，则返回值为零。要获取错误信息。能够调用GetLastError 。

3.2、cliopt.parse(argc, argv)

cliopt.parse(argc, argv)的主要功能是分析參数，直接调用x265.cpp中的bool CLIOptions::parse(int argc, char **argv)函数，该函数会打印输入视频的分辨率、帧率、视频格式、所要编码的帧数目以及输出文件名等。例如以下图所看到的：

相应的代码例如以下：

bool CLIOptions::parse(int argc, char **argv)
{
    bool bError = false;
    int bShowHelp = false;
    int inputBitDepth = 8;
    int outputBitDepth = 0;
    int reconFileBitDepth = 0;
    const char *inputfn = NULL;
    const char *reconfn = NULL;
    const char *outputfn = NULL;
    const char *preset = NULL;
    const char *tune = NULL;
    const char *profile = NULL;

    if (argc <= 1)
    {
        x265_log(NULL, X265_LOG_ERROR, "No input file. Run x265 --help for a list of options.\n");
        return true;
    }

    /* Presets are applied before all other options. */
    for (optind = 0;; )
    {
        int c = getopt_long(argc, argv, short_options, long_options, NULL);
        if (c == -1)
            break;
        else if (c == 'p')
            preset = optarg;
        else if (c == 't')
            tune = optarg;
        else if (c == 'D')
            outputBitDepth = atoi(optarg);
        else if (c == 'P')
            profile = optarg;
        else if (c == '?

')
            bShowHelp = true;
    }

    if (!outputBitDepth && profile)
    {
        /* try to derive the output bit depth from the requested profile */
        if (strstr(profile, "10"))
            outputBitDepth = 10;
        else if (strstr(profile, "12"))
            outputBitDepth = 12;
        else
            outputBitDepth = 8;
    }

    api = x265_api_get(outputBitDepth);
    if (!api)
    {
        x265_log(NULL, X265_LOG_WARNING, "falling back to default bit-depth\n");
        api = x265_api_get(0);
    }

    param = api->param_alloc();
    if (!param)
    {
        x265_log(NULL, X265_LOG_ERROR, "param alloc failed\n");
        return true;
    }

    if (api->param_default_preset(param, preset, tune) < 0)
    {
        x265_log(NULL, X265_LOG_ERROR, "preset or tune unrecognized\n");
        return true;
    }

    if (bShowHelp)
    {
        printVersion(param, api);
        showHelp(param);
    }

    for (optind = 0;; )
    {
        int long_options_index = -1;
        int c = getopt_long(argc, argv, short_options, long_options, &long_options_index);
        if (c == -1)
            break;

        switch (c)
        {
        case 'h':
            printVersion(param, api);
            showHelp(param);
            break;

        case 'V':
            printVersion(param, api);
            x265_report_simd(param);
            exit(0);

        default:
            if (long_options_index < 0 && c > 0)
            {
                for (size_t i = 0; i < sizeof(long_options) / sizeof(long_options[0]); i++)
                {
                    if (long_options[i].val == c)
                    {
                        long_options_index = (int)i;
                        break;
                    }
                }

                if (long_options_index < 0)
                {
                    /* getopt_long might have already printed an error message */
                    if (c != 63)
                        x265_log(NULL, X265_LOG_WARNING, "internal error: short option '%c' has no long option\n", c);
                    return true;
                }
            }
            if (long_options_index < 0)
            {
                x265_log(NULL, X265_LOG_WARNING, "short option '%c' unrecognized\n", c);
                return true;
            }
#define OPT(longname) \
    else if (!strcmp(long_options[long_options_index].name, longname))
#define OPT2(name1, name2) \
    else if (!strcmp(long_options[long_options_index].name, name1) || \
             !strcmp(long_options[long_options_index].name, name2))

            if (0) ;
            OPT2("frame-skip", "seek") this->seek = (uint32_t)x265_atoi(optarg, bError);
            OPT("frames") this->framesToBeEncoded = (uint32_t)x265_atoi(optarg, bError);
            OPT("csv") this->csvfn = optarg;
            OPT("csv-log-level") this->csvLogLevel = x265_atoi(optarg, bError);
            OPT("no-progress") this->bProgress = false;
            OPT("output") outputfn = optarg;
            OPT("input") inputfn = optarg;
            OPT("recon") reconfn = optarg;
            OPT("input-depth") inputBitDepth = (uint32_t)x265_atoi(optarg, bError);
            OPT("dither") this->bDither = true;
            OPT("recon-depth") reconFileBitDepth = (uint32_t)x265_atoi(optarg, bError);
            OPT("y4m") this->bForceY4m = true;
            OPT("profile") /* handled above */;
            OPT("preset")  /* handled above */;
            OPT("tune")    /* handled above */;
            OPT("output-depth")   /* handled above */;
            OPT("recon-y4m-exec") reconPlayCmd = optarg;
            OPT("qpfile")
            {
                this->qpfile = fopen(optarg, "rb");
                if (!this->qpfile)
                {
                    x265_log(param, X265_LOG_ERROR, "%s qpfile not found or error in opening qp file\n", optarg);
                    return false;
                }
            }
            else
                bError |= !!api->param_parse(param, long_options[long_options_index].name, optarg);

            if (bError)
            {
                const char *name = long_options_index > 0 ? long_options[long_options_index].name : argv[optind - 2];
                x265_log(NULL, X265_LOG_ERROR, "invalid argument: %s = %s\n", name, optarg);
                return true;
            }
#undef OPT
        }
    }

    if (optind < argc && !inputfn)
        inputfn = argv[optind++];
    if (optind < argc && !outputfn)
        outputfn = argv[optind++];
    if (optind < argc)
    {
        x265_log(param, X265_LOG_WARNING, "extra unused command arguments given <%s>\n", argv[optind]);
        return true;
    }

    if (argc <= 1)
    {
        api->param_default(param);
        printVersion(param, api);
        showHelp(param);
    }

    if (!inputfn || !outputfn)
    {
        x265_log(param, X265_LOG_ERROR, "input or output file not specified, try --help for help\n");
        return true;
    }

    if (param->internalBitDepth != api->bit_depth)
    {
        x265_log(param, X265_LOG_ERROR, "Only bit depths of %d are supported in this build\n", api->bit_depth);
        return true;
    }

    InputFileInfo info;
    info.filename = inputfn;
    info.depth = inputBitDepth;
    info.csp = param->internalCsp;
    info.width = param->sourceWidth;
    info.height = param->sourceHeight;
    info.fpsNum = param->fpsNum;
    info.fpsDenom = param->fpsDenom;
    info.sarWidth = param->vui.sarWidth;
    info.sarHeight = param->vui.sarHeight;
    info.skipFrames = seek;
    info.frameCount = 0;
    getParamAspectRatio(param, info.sarWidth, info.sarHeight);

    this->input = InputFile::open(info, this->bForceY4m);
    if (!this->input || this->input->isFail())
    {
        x265_log(param, X265_LOG_ERROR, "unable to open input file <%s>\n", inputfn);
        return true;
    }

    if (info.depth < 8 || info.depth > 16)
    {
        x265_log(param, X265_LOG_ERROR, "Input bit depth (%d) must be between 8 and 16\n", inputBitDepth);
        return true;
    }

    /* Unconditionally accept height/width/csp from file info */
    param->sourceWidth = info.width;
    param->sourceHeight = info.height;
    param->internalCsp = info.csp;

    /* Accept fps and sar from file info if not specified by user */
    if (param->fpsDenom == 0 || param->fpsNum == 0)
    {
        param->fpsDenom = info.fpsDenom;
        param->fpsNum = info.fpsNum;
    }
    if (!param->vui.aspectRatioIdc && info.sarWidth && info.sarHeight)
        setParamAspectRatio(param, info.sarWidth, info.sarHeight);
    if (this->framesToBeEncoded == 0 && info.frameCount > (int)seek)
        this->framesToBeEncoded = info.frameCount - seek;
    param->totalFrames = this->framesToBeEncoded;

    /* Force CFR until we have support for VFR */
    info.timebaseNum = param->fpsDenom;
    info.timebaseDenom = param->fpsNum;

    if (api->param_apply_profile(param, profile))
        return true;

    if (param->logLevel >= X265_LOG_INFO)
    {
        char buf[128];
        int p = sprintf(buf, "%dx%d fps %d/%d %sp%d", param->sourceWidth, param->sourceHeight,
                        param->fpsNum, param->fpsDenom, x265_source_csp_names[param->internalCsp], info.depth);

        int width, height;
        getParamAspectRatio(param, width, height);
        if (width && height)
            p += sprintf(buf + p, " sar %d:%d", width, height);

        if (framesToBeEncoded <= 0 || info.frameCount <= 0)
            strcpy(buf + p, " unknown frame count");
        else
            sprintf(buf + p, " frames %u - %d of %d", this->seek, this->seek + this->framesToBeEncoded - 1, info.frameCount);

        general_log(param, input->getName(), X265_LOG_INFO, "%s\n", buf);
    }

    this->input->startReader();

    if (reconfn)
    {
        if (reconFileBitDepth == 0)
            reconFileBitDepth = param->internalBitDepth;
        this->recon = ReconFile::open(reconfn, param->sourceWidth, param->sourceHeight, reconFileBitDepth,
                                      param->fpsNum, param->fpsDenom, param->internalCsp);
        if (this->recon->isFail())
        {
            x265_log(param, X265_LOG_WARNING, "unable to write reconstructed outputs file\n");
            this->recon->release();
            this->recon = 0;
        }
        else
            general_log(param, this->recon->getName(), X265_LOG_INFO,
                    "reconstructed images %dx%d fps %d/%d %s\n",
                    param->sourceWidth, param->sourceHeight, param->fpsNum, param->fpsDenom,
                    x265_source_csp_names[param->internalCsp]);
    }

    this->output = OutputFile::open(outputfn, info);
    if (this->output->isFail())
    {
        x265_log(param, X265_LOG_ERROR, "failed to open output file <%s> for writing\n", outputfn);
        return true;
    }
    general_log(param, this->output->getName(), X265_LOG_INFO, "output file: %s\n", outputfn);
    return false;	//完毕后返回false
}

3.3、encoder_open()函数

encoder_open(param)的主要功能是打印编码器的配置信息，直接调用api.cpp中的x265_encoder *x265_encoder_open(x265_param *p)，该函数中调用了x265_print_params(param)用以打印编码器配置信息，例如以下图所看到的：

相应的代码例如以下：

x265_encoder *x265_encoder_open(x265_param *p)
{
    if (!p)
        return NULL;

#if _MSC_VER
#pragma warning(disable: 4127) // conditional expression is constant, yes I know
#endif

#if HIGH_BIT_DEPTH
    if (X265_DEPTH == 12)
        x265_log(p, X265_LOG_WARNING, "Main12 is HIGHLY experimental, do not use!\n");
    else if (X265_DEPTH != 10 && X265_DEPTH != 12)
#else
    if (X265_DEPTH != 8)
#endif
    {
        x265_log(p, X265_LOG_ERROR, "Build error, internal bit depth mismatch\n");
        return NULL;
    }

    Encoder* encoder = NULL;
    x265_param* param = PARAM_NS::x265_param_alloc();
    x265_param* latestParam = PARAM_NS::x265_param_alloc();
    if (!param || !latestParam)
        goto fail;

    memcpy(param, p, sizeof(x265_param));
    x265_log(param, X265_LOG_INFO, "HEVC encoder version %s\n", PFX(version_str));
    x265_log(param, X265_LOG_INFO, "build info %s\n", PFX(build_info_str));

    x265_setup_primitives(param);

    if (x265_check_params(param))
        goto fail;

    if (x265_set_globals(param))
        goto fail;

    encoder = new Encoder;
    if (!param->rc.bEnableSlowFirstPass)
        PARAM_NS::x265_param_apply_fastfirstpass(param);

    // may change params for auto-detect, etc
    encoder->configure(param);
    // may change rate control and CPB params
    if (!enforceLevel(*param, encoder->m_vps))
        goto fail;

    // will detect and set profile/tier/level in VPS
    determineLevel(*param, encoder->m_vps);

    if (!param->bAllowNonConformance && encoder->m_vps.ptl.profileIdc == Profile::NONE)
    {
        x265_log(param, X265_LOG_INFO, "non-conformant bitstreams not allowed (--allow-non-conformance)\n");
        goto fail;
    }

    encoder->create();
    encoder->m_latestParam = latestParam;
    memcpy(latestParam, param, sizeof(x265_param));
    if (encoder->m_aborted)
        goto fail;

    x265_print_params(param);	//打印參数
    return encoder;

fail:
    delete encoder;
    PARAM_NS::x265_param_free(param);
    PARAM_NS::x265_param_free(latestParam);
    return NULL;
}

3.4、encoder_headers()函数

int x265_encoder_headers(x265_encoder *enc, x265_nal **pp_nal, uint32_t *pi_nal)
{
    if (pp_nal && enc)
    {
        Encoder *encoder = static_cast<Encoder*>(enc);
        Entropy sbacCoder;
        Bitstream bs;
        encoder->getStreamHeaders(encoder->m_nalList, sbacCoder, bs);	//get Stream Headers
        *pp_nal = &encoder->m_nalList.m_nal[0];
        if (pi_nal) *pi_nal = encoder->m_nalList.m_numNal;
        return encoder->m_nalList.m_occupancy;
    }

    return -1;
}

3.5、encoder_encode()函数

int x265_encoder_encode(x265_encoder *enc, x265_nal **pp_nal, uint32_t *pi_nal, x265_picture *pic_in, x265_picture *pic_out)
{
    if (!enc)
        return -1;

    Encoder *encoder = static_cast<Encoder*>(enc);
    int numEncoded;

    // While flushing, we cannot return 0 until the entire stream is flushed
    do
    {
        numEncoded = encoder->encode(pic_in, pic_out);	//==========进入编码函数
    }
    while (numEncoded == 0 && !pic_in && encoder->m_numDelayedPic);

    // do not allow reuse of these buffers for more than one picture. The
    // encoder now owns these analysisData buffers.
    if (pic_in)
    {
        pic_in->analysisData.intraData = NULL;
        pic_in->analysisData.interData = NULL;
    }

    if (pp_nal && numEncoded > 0)
    {
        *pp_nal = &encoder->m_nalList.m_nal[0];
        if (pi_nal) *pi_nal = encoder->m_nalList.m_numNal;
    }
    else if (pi_nal)
        *pi_nal = 0;

    return numEncoded;
}

3.6、encoder_close()函数

void x265_encoder_close(x265_encoder *enc)
{
    if (enc)
    {
        Encoder *encoder = static_cast<Encoder*>(enc);

        encoder->stopJobs();
        encoder->printSummary();	//==========打印总结信息
        encoder->destroy();
        delete encoder;
        ATOMIC_DEC(&g_ctuSizeConfigured);
    }
}

到这儿。main()函数的主要功能就分析完成了。