A multi-faceted vehicle, Jason is capable of carrying a wide variety of sampling apparatus and of performing many different activities. We provide several documents describing NDSF-maintained data systems and the content that Jason users will receive from them.
Jason’s primary navigation sources are a Doppler velocity log (DVL) in combination with a fiber optic gyroscope (FOG). This information is usually augmented with georeferenced information from an ultra-short baseline (USBL) system. During a dive both histories are displayed in real time and logged by in-house softwares navest and NavG. The two histories are mathematically merged in post-dive processing to yield an improved history. For those dives that are out of DVL range, a smoothed USBL-based product is delivered.
We recommend bringing to your cruise previously collected navigation and bathymetry, with historical station positions, to increase the efficiency and productivity of your dive time. Jason navigators can guide you in the creation of underlays and waypoints and will incorporate this information into operational software for use in real time. Prior to your cruise, the NDSF data manager can assist you finding information and processing content.
Jason carries a variety of video and still camera systems, generally described in the Jason User Manual. Please discuss your project’s needs with the Jason team during the pre-cruise process. The Jason control van houses a variety of imagery capture systems that have differing behaviors depending on source and time of development.
Constant Video Recording
Three video cameras (“pilot”, “brow”, and “science”) are captured by duplicate direct-to-hard drive recorders. Video and accompanying files are clipped at a definable time, usually 15 minutes. The codec is h.264, which provides excellent viewing quality but is unsuitable for production video editing. File volumes are about 2.4GB per hour per camera. The processing of these clips requires about 15 minutes per hour of dive time. Video and subtitle files are merged in post-processing to yield a video with optional overlays, playable using software such as vlc.
For those moments that may be processed for outreach, select activities of the dive can optionally be captured from the watchstander’s choice of high definition (1080i) pilot, brow, or ultra HD (2160p/4K) science camera streams. These clips are compressed using the Apple ProRes422 family of codecs (2.7GB/3 minutes for high definition, 15GB/3 minutes ultra definition) and contain embedded time code. The resulting file is a .mov file type, playable by QuickTime and editable using NLE software such as Final Cut or Premiere.
Several sources of still images from Jason cameras are now available.
- Simultaneous still grabbed images from two of the video streams from the science, pilot, or brow, or still image cameras, as selected by science watchstanders. The system produces color RGB TIFF images at 1920x1080 x 8 bits of quantization.
- Standard still camera. Sulis 4k (new March 2018), which produces 5968x3352 images in jpeg format.
- Photo survey systems.
- A machine vision camera & dscam software that is alternatively used for periodic (~10 seconds) downlooking shots, from which Bayer-coded TIFFs, color TIFFS, and color jpegs are produced. By pre-cruise
- Still images from the various Insite mini-Zeus cameras (SciCam, BrowCam, PilotCam), with the control set to a periodic sampling period. The uncertainties of controlling the pan and tilt mounts and the camera zooms may demand complex post-processing, but this offers an alternative when a downlooking configuration cannot be supported.
Jason lighting is now improved by use of LED technology, but some limitations on camera configurations exist. In particular, downlooking captures require use of strobes that can be flashed no more quickly than every ~10 seconds. Please be sure to discuss photographic requirements in the pre-cruise process.
All image filenames denote image capture time. A post-processed product merges vehicle navigation to image filename at the time the image was captured (.ppfx file).
Logging of Events
We are phasing in a new event log/dive summary system called sealog, and run sealog along with the Jason Virtual Van. Sealog provides an event logger interface, and both systems capture event science party commentary with sensor data and video grabs. Event hot buttons ease comment entry and standardize vocabulary. Currently we deliver VirtualVan content. We suggest that prior to the cruise you obtain or develop a hot button list according to the standards of your research community. Some vocabularies can be obtained from http://marinemetadata.org/guides/vocabs
Jason can carry a 400 kHz Reson Seabat 7125 multibeam sonar. Use of the Seabat 7125 should be arranged in the pre-cruise process, and the chief scientist may wish to bring personnel who specialize in the production of bathymetry maps. The Jason at-sea data processor will produce a quick-look gridded product that is based on a first-cut renavigation and multibeam soundings that have been processed using automated scripts.
Jason’s additional standard sensors include a dedicated pressure sensor from ParoScientific, an Aanderaa 4330 optical optode, a magnetometer, Reson SVP, and an RTD-based temperature probe. The Seabird Seacat19v2 CTD is typically used in a free-run ASCII output mode: alternate uses of the CTD should be addressed prior to the cruise and may require a dedicated watchstander from the science party.
The cruise data package will be placed on hard drive and will consist of
- all raw Jason sensor
- video as described
- still images
- tables (.csv) of sensors data, subsampled and
- metadata and
- Post-processed navigation
- Quick-look multibeam maps and raw multibeam ping files, when
- VirtualVan, provided by two methods:
- network-independent html hierarchy that can be viewed using a web
- after the cruise on password-protectable server at http://4dgeo.whoi.edu/jason
Data Package Media
We will provide a portable hard drive system and will deliver the data package on it to the chief scientist at the end of the cruise. The standard filesystem for the package is ExFAT, which is compatible with Windows Vista and later, MacOSX Snow Leopard and later, and linux with extensions. The Jason data processor will provide intermediary versions of the data package (excepting video highlights) throughout the cruise via a NAS share.
The media containing the data package will be suitable for transport and temporary housing of the data, but should not be used for permanent storage. Once back at your institution, please be sure to transfer the data to enterprise quality storage.
When data package is delivered at the end of the cruise, chief scientist will be asked to:
(1) review a form that describes the package inventory and provides details for returning the drives to WHOI and acknowledge delivery of the package.
(2) assign embargo duration on the various data components (NSF policy states maximum 2-years).
(3) name institutions for whom acknowledgement is due when cruise data is used for outreach or commercial purposes.