IS-1500 User Guide
Thales Visionix, Inc.
MNL- 0024 (D)
Page 39 of 59
5.3
sfHub.info
The sfHub.info file is located in the sfHub subfolder of the software directory. It is broken up into four sections- General, IS1500, Vins,
and FusionCore.
5.3.1
Logging and Playback of Tracking Data
In addition to the methods sfStudio uses for capturing tracking data, sfHub has a built in logging function that collects image and
IMU data directly from the InertiaCam as it’s received. This data can be used to replay tracking runs for experiments, simulations,
presentations, or any other applications that require repeatable data. Once enabled, a new log is collected each time streaming is
started in sfHub.
As a warning, this logging function is not to be confused with that which creates a text file (sfHub.log) indicating program errors,
etc. This process saves each frame as an image rather than as a video to prevent encoding interfering with playback. While this
ensures that the data captured is faithful to the original tracking data and is repeatable, it also means that log files tend to be large.
It is recommended that several gigabytes of hard drive space are free before collecting a number of logs. It is also very important
to disable logging once the desired data has been collected. The data is not overwritten when sfHub is restarted and, if it’s not
disabled, will continue to consume hard drive space until the hard drive is full.
Also, logging is more computationally intensive than tracking. It is recommended that prior to and while logging tracking data,
background and end-user applications are closed and only sfHub and sfStudio are run. For optimal performance, do not perform
any tasks while sfHub is running with logging or playback enabled, including mouse clicks or typing. This is because of the way
sfHub processes incoming data. If the data queue is temporarily overloaded due to processing limitations, IMU records or image
frames will be dropped. While not an issue during live tracking, dropping records during playback can cause a butterfly effect that
will change the outcome of the otherwise reproducible replay.
A. To collect a log, follow the steps below.
1.
If they are currently running, close the sfHub and sfStudio programs.
2.
Open the sfHub.info file.
3.
Under the General section, find the Master subsection and set logData
1
.
General
{
appMode 1
; (1) Tracking (2) Playback (3) Configuration Utility
numSensors 1
; (1) Min (4) Max
verbosity 0
; (0) Low (1) Med (2) High
Master
{
; (1) sfCore 3DOF
; (2) sfCore 6DOF
; (3) NFT + Fid
; (4) NFT + GPS
; (5) NFT + GPS + Fid
trkMode 3
sensorType 2
; (1) HObIT (2) InertiaCam
initState 1
; (1) Streaming, (0) Paused
logData
1
; (1) Enable data logging
}
}
4.
Save and close sfHub.info.