【寒武纪硬件产品型号】：MLU270

【使用操作系统】必填：Kylin Linux Desktop V10(sp1)

【使用驱动版本】：neuwar-mlu270-driver-dkms_4.8.0_all.deb

【出错信息】必填*：初始化设置输入缓存和输出缓存为1，回调后输出缓存变成了5，不能强制设置为1

【操作步骤】选填:

初始化设置输入缓存和输出缓存为1

    int video_decoder_hwj::initDecodeContext(videoDecodeContext *pContext){
          memset(&pContext->decInfo, 0, sizeof(pContext->decInfo));

          pContext->decInfo.codec = CNCODEC_H264;
          if(m_enc_param->codec_params.codec ==  work::VideoCodec::H264)
          {
            pContext->decInfo.codec = CNCODEC_H264;
          }else if(m_enc_param->codec_params.codec ==  work::VideoCodec::HEVC)
          {
            pContext->decInfo.codec = CNCODEC_HEVC;          
          }
          
          pContext->decInfo.width = m_enc_param->width;
          pContext->decInfo.height = m_enc_param->height;
          pContext->decInfo.inputBufNum = 1;
          pContext->decInfo.outputBufNum = 1;
          pContext->decInfo.pixelFmt = cncodecPixelFormat::CNCODEC_PIX_FMT_I420; // 420 OR NV12
          pContext->decInfo.progressive = 1;
          // callbackevent pUserdata
          pContext->decInfo.userContext = reinterpret_cast<void*>(this);

          pContext->decInfo.instance = cnvideoDecInstance::CNVIDEODEC_INSTANCE_1;
          pContext->decInfo.allocType = CNCODEC_BUF_ALLOC_LIB;//CNCODEC_BUF_ALLOC_APP;
        
          /* allocate input and output buffer */
          if (pContext->decInfo.allocType == CNCODEC_BUF_ALLOC_APP) {
            pContext->decInfo.inputBuf = (cncodecDevMemory *)malloc(pContext->decInfo.inputBufNum * sizeof(cncodecDevMemory));
            pContext->decInfo.outputBuf = (cncodec  *)malloc(pContext->decInfo.outputBufNum * sizeof(cncodec ));
            pContext->outputBufMap = ( CpuAddr *)malloc(pContext->decInfo.outputBufNum * sizeof( CpuAddr));
            pContext->inputBufMap = (uint64_t *)malloc(pContext->decInfo.inputBufNum * sizeof(uint64_t));
        
            cnrtContextInit(0, getBestChannelForDecoder(0));
            printf("initDecodeContext --- call allocateDecodeBuffer-------\n");
            allocateDecodeBuffer(pContext);
          }
        
          pContext->eos = false;
          sem_init(&(pContext->eosSemaphore), 0, 0);
  
          return 0;        
        }

回调后

pContext->seqinfo.minOutputBufNum 为5，强制设置pContext->decInfo.outputBufNum = 1 也不成功

        int video_decoder_hwj::HandleSequenceEvent(cnvideoDecSequenceInfo *pFormat) {
          int ret = 0;
          m_pContext->seqinfo = *pFormat;
          
          updateDecodeContext(m_pContext);
                             
          // start decode
          ret = cnvideoDecStart(m_pContext->handle,&m_pContext->decInfo);
          if (ret != CNCODEC_SUCCESS) {
            printf("cnvideoDecStart fail, ret(%d)\n", ret);
            return -1;
          }
        
          return 0;
        }
        
        
        int video_decoder_hwj::updateDecodeContext(videoDecodeContext *pContext) {
          printf("updateDecodeContext --------\n");
          cnrtContextInit(0, getBestChannelForDecoder(0));
                  
          // release output buffer
          if (pContext->decInfo.allocType == CNCODEC_BUF_ALLOC_APP) {
            free(pContext->decInfo.outputBuf);
            releaseDecodeOutputBuffer(pContext);
          }
        
          // update decode info
          pContext->decInfo.codec = pContext->seqinfo.codec;          
          pContext->decInfo.height = pContext->seqinfo.height;
          pContext->decInfo.width = pContext->seqinfo.width;
          // update exit buufer ?  >1 ??????????????TODO outputBufNumMin == 5
          pContext->decInfo.inputBufNum = pContext->seqinfo.minInputBufNum;
          pContext->decInfo.outputBufNum = pContext->seqinfo.minOutputBufNum > pContext->decInfo.outputBufNum
                                               ? pContext->seqinfo.minOutputBufNum
                                               : pContext->decInfo.outputBufNum;
          printf("inputBufNum-------%d output=%d width=%d height=%d \n", pContext->decInfo.inputBufNum, pContext->decInfo.outputBufNum, pContext->decInfo.width, pContext->decInfo.height);                                               
          pContext->decInfo.userContext = (void *)pContext;
        
          // re-allocate output(capture) buffer
          if (pContext->decInfo.allocType == CNCODEC_BUF_ALLOC_APP) {
            pContext->decInfo.outputBuf = (cncodec  *)malloc(pContext->decInfo.outputBufNum * sizeof(cncodec ));
            printf("updateDecodeContext --------call allocateDecodeOutputBuffer\n");
            allocateDecodeOutputBuffer(pContext);
          }
        
          return 0;
        }