XSort 0.1.5

Version 0.1.5 (04/29/2024)

• Extend support to non-Omniplex recordings in which the analog source is a flat binary file. The file may be
  interleaved (or not), and prefiltered (or not). Splitting analog channel streams into separate internal cache
  files is unnecessary when the analog source is a flat, prefiltered binary file.
• When "opening" a working directory for the first time, XSort will query user via dialog if there are multiple
  possible analog and/or unit source files, and/or if the analog source is a flat binary file. In the case of a flat
  binary source, the user must specify the sampling rate and number of channels recorded, the scale factor converting
  a raw binary sample to volts, whether or not the analog channel streams are interleaved, and whether or not the
  data is prefiltered. Once a valid directory configuration is specified, the configuration info is saved to an
  internal file (.xs.directory.txt) so that the user does not have to reenter the information the next time XSort
  visits the directory.
• Major redesign of the infrastructure/strategy for background task processing to improve performance and handle
  recording sessions with hundreds of analog channels and hundreds of neural units.
  • Divide up work among multiple processses where possible -- especially helpful for the building the internal
    cache for an XSort directory, and for computing statistics for units in the current display/focus list.
  • Evaluated a number of different approaches to handle the "build internal cache" task, using a Neuropixel
    session with 385 analog channels and 482 units.
  • We now only compute a unit's per-channel spike templates on up to 16 analog channels "in the neighborhood" of
    the unit's primary channel (channel exhibiting highest SNR). Since XSort does not yet support the notion of probe
    geometry, we use channel indices [P-8 .. P+7], where P is the primary channel index.
  • Greatly improved the algorithm for computing noise levels on each analog channel. The per-channel noise levels
    are calculated and cached as part of the "build internal cache" task -- after caching analog channels (if needed),
    but before caching neural unit metrics.
  • When there are more than 16 recorded analog channels, building the unit metrics cache files has two phases. First,
    a background task identifies the primary channel P for each unit. Then, a second background task computes the spike
    templates for the channels near each unit's primary channel and writes each unit's metrics (spike times, templates,
    snr, primary channel) to an internal cache file (.xs.unit.<uid>).
• Modified TemplateView implementation:
  • Precreate and reuse graphics items that render the templates and display channel labels. This is more efficient
    than destroying and recreating them every time -- improving overall GUI responsiveness.
  • Vertical span is auto-adjusted whenever there is a change in the displayed templates. User can still readjust the
    span using the slider provided.
• Modified ChannelView implementation:
  • Adjusts the visible Y-axis range whenever the user explicitly changes the vertical separation between trace so that,
    if the user has zoomed in on a few traces, those traces remain approximately in the same place after the change.
  • Precreate and reused graphics items that render channel traces and spike clips. Again, this is more efficient and
    improved overall GUI responsiveness.
  • Vertical trace offset is auto-adjusted whenever the channel traces are updated (this also resets the zoom/pan
    state). User can still readjust the trace offset using the slider provided.

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Installation Instructions

See README.