| Literature DB >> 28261545 |
Benedikt J Daurer1, Hari Krishnan2, Talita Perciano2, Filipe R N C Maia1,3, David A Shapiro4, James A Sethian2,5, Stefano Marchesini2.
Abstract
BACKGROUND: The ever improving brightness of accelerator based sources is enabling novel observations and discoveries with faster frame rates, larger fields of view, higher resolution, and higher dimensionality.Entities:
Keywords: Ptychography; Streaming
Year: 2017 PMID: 28261545 PMCID: PMC5313566 DOI: 10.1186/s40679-017-0039-0
Source DB: PubMed Journal: Adv Struct Chem Imaging ISSN: 2198-0926
Fig. 1Streaming pipeline: Overview of the real-time streaming framework of Nanosurveyor. The modular server–client infrastructure is divided into a back-end (running the data processing unit) and a front-end (running the visualization and control unit). The data flow is depicted as a red arrow, while communication channels for controlling experiment and back-end are shown in gray. Once an experiment has started (trigger signal), the data collection unit continuously receives new data packets from a detector and sends raw data frames to the data processing unit. Depending on the specific needs of the experiment, different modules (from dark calibration to data writing) can be plugged into the pipeline. At all times, there is an active connection (asynchronous socket communication) between all components (including the visualization interface) allowing the scientist to monitor progress while data are still being acquired and processed
Fig. 2Ptychographic streaming pipeline: streaming pipeline implemented at the ALS for ptychographic imaging. The software structure follows the same logic as sketched in Fig. 1. Once a new scan has been triggered by the experimental control, a frame-grabber continuously receives raw data packets from the camera, assembles them to a frame and sends raw frames to the back-end. Incoming frames are processed by different (and independent) workers of the back-end and reduced data are sent back to the front-end and visualized in a graphical user interface (GUI). The pipeline includes a dark worker for dark correction, multiple frame workers for pre-processing and data reduction, an image worker for low-resolution image reconstruction and a SHARP worker for high-resolution ptychographic image reconstruction. A handler is coordinating the data and communication workflow in which different types of control and data plugs (sockets) are used. While most of the components communicate via the transmission control protocol (TCP), the raw data packets from the camera are sent via the user datagram protocol (UDP)
Fig. 3Graphical user interface (GUI): for the ptychographic streaming pipeline implemented at the ALS. The interface provides a real-time view of the ptychographic reconstruction (high resolution), b real-time view of the STXM analysis (low resolution), c current guess of the illumination function, d current processed data frame, e logging and error messages and f error metrics of the iterative reconstruction process, and other control and monitoring elements around