Record Ultrasound Sweeps

Records (grabs) data from one or multiple image streams and a live tracking stream.

Input

The algorithm requires at least one ImageStream and exactly one LiveTrackingStream as input. Instead of the individual image streams, a data group collecting all of them can be provided. In the latter case, the algorithm will automatically include (sub)streams later added to the data group.

Output

For each recording, a set of Ultrasound sweeps is produced, which might be added to the data model and/or saved to the file system, according to the settings.

Description

After clicking Start recording , the algorithm will start accumulating (copying) incoming 2D images and tracking information in memory. No synchronization or temporal resampling is hereby performed: The Ultrasound sweep data structure keeps timestamps for both images and tracking information and stores all incoming data without any modification. Whenever a combination of image and tracking matrix is required, the appropriate matrix is searched using the timestamp. The button Stop recording finalizes the recording

According to Keep last ... in data panel, the resulting sweeps are added to the data model. Previous sweeps are removed once the limit is reached. Substreams of a data group are not added to the data model unless saving to the file system is disabled.

If Automatic Storage is active, all resulting sweeps are saved to the file system:

  • The Directory for all data to be stored is adjusted in the advanced settings.
  • The field Patient Name is used for both the name of the subfolder, as well as the base name of the sweep file.
  • For each recording, a sequence number is incremented and added to the base name.
  • Finally, an optional Description is stripped of special characters and also added to the file name. Note that the sequence number is independent of the description string.

The final path of the file is thus: Directory/PatientName/PatientName-SeqNo-Description.imf, if the DICOM format is disabled. Substream sweeps are saved in a file with the identical name in a RawData subfolder. In addition, a log file of the form Directory/PatientName/PatientName.txt is created, for which additional log messages can be recorded using the Log field and the two buttons Save and CM (for “camera moved”). The button Discard Last Sweep removes the last recording both from the data model and the file system.

The algorithm allows setting the following advanced parameters:

  • Record all tracking target: Defines whether all tracking devices will be recorded or just the selected one. Default is on.
  • Compress: Defines if the output files will be compressed before saving. Default is off.
  • Tint image if tracking is lost: Colors the live 2D ultrasound red of the tracking quality drops.
  • Time limit: Defines the maximum recording time. Default is none.
  • Frames limit: Defines the maximum number of recorded images. Default is none.
  • Tracking data limit: Defines the maximum number of recorded tracking samples. Default is none.
  • Memory limit: Defines the maximum fraction of RAM to be exhausted before recording stops automatically. Default is 90%.
  • Tracker button click speed: Defines the minimum duration a tracking device button needs to remain pressed to start/stop the recording.
  • Sweep buffer: Defines the number of frames that are shown in the view as part of the Live Sweep visualization.
  • Resample: Defines whether the incoming images should be resampled before saving. Default is off.