x264编码参数设置

H264Encoder *pEn = (H264Encoder *) AllocBuffer(sizeof(H264Encoder));
pEn->param = (x264_param_t *) AllocBuffer(sizeof(x264_param_t));
x264_param_default(pEn->param); //set default param

/*设置profile属性*/
//x264_profile_names数组定义如下：static const char * const x264_profile_names[] =
//{ "baseline", "main", "high", "high10", "high422", "high444", 0 };
x264_param_apply_profile(pEn->param,x264_profile_names[0]);

pEn->param->i_csp = X264_CSP_I420;// 设置帧数据格式为420
pEn->param->i_width = m_nPicW; // 设置帧宽度
pEn->param->i_height = m_nPicH; // 设置帧高度
pEn->param->rc.i_lookahead = 0;

pEn->param->i_fps_num = m_nFps; // 设置帧率（分子）
pEn->param->i_fps_den = 1; // 设置帧率时间1s（分母）

pEn->param->rc.i_bitrate = m_nBitrate; // 设置码率
pEn->param->rc.i_vbv_max_bitrate = pCodecParam->encoder.iMaxBitrate; // 设置平均码率模式下，最大瞬时码率
pEn->param->i_keyint_max = m_nFps * 2; // 设置GOP最大长度
pEn->param->i_keyint_min = m_nFps * 2; // 设置GOP最小长度

pEn->param->pf_log = x264_log; // 设置打印日志回调
pEn->param->p_log_private = NULL;
pEn->param->i_log_level = X264_LOG_WARNING;
pEn->param->b_vfr_input = 0; // 1:使用timebase和时间戳做码率控制 0：只使用fps做码率控制

pEn->param->i_timebase_num = 1; // timebase（分子）
pEn->param->i_timebase_den = 1000; // timebase（分母）

pEn->param->b_repeat_headers = 0; // 1:在每个关键帧前面放sps和pps
pEn->param->i_threads = 1; // 并行编码多个帧线程数
pEn->param->rc.i_rc_method = X264_RC_ABR; // 码率控制方法，CQP(恒定质量)，CRF(恒定码率)，ABR(平均码率)
pEn->param->rc.i_vbv_buffer_size = pCodecParam->encoder.iMaxBitrate; //码率控制缓冲区的大小，单位kbit，默认0

pEn->handle = x264_encoder_open(pEn->param); // 创建一个新的编码器句柄