/**
 * [[VideoFrameProcessorPipelineObserver]] is the observer for  VideoFrameProcessorPipeline to receive lifecycle or performance callbacks.
  export default interface VideoFrameProcessorPipelineObserver { /**
     * `processingDidStart` will be called when  VideoFrameProcessorPipeline starts streaming.
      processingDidStart ? ( ) : void ; /**
     * `processingDidFailToStart` will be called when  VideoFrameProcessorPipeline could not start streaming due to runtime errors.
      processingDidFailToStart ? ( ) : void ; /**
     * `processingDidStop` will be called when  VideoFrameProcessorPipeline stops streaming expectedly.
      processingDidStop ? ( ) : void ; /**
     * `processingLatencyTooHigh` will be called when the execution of  VideoFrameProcessorPipeline slows the frame rate down by half.
      processingLatencyTooHigh ? ( latencyMs ) : void ; }