The Tracking Analyzer module performs the extraction of the measured parameters from the trajectory of the tracked object. The unit of measurement of each parameter and the specific parameter(s) to extract from different zones can be set. As in the case of the Tracker module, zone settings (including parameter settings) and individual parameter settings can be as templates and . After finishing the operation, clicking will either the close the module, or return the user to the caller module.
Loading trajectories
Trajectories are stored in simple text files as a series of x-y coordinates separated by whitespace (decimals are separated by a dot). The ordinal numbers of the frames are signified by the ordinal numbers of the rows (as in, the first row contains the coordinates appertaining to the first frame). Frames to which coordinates are not allocated are signified by “null”.
To load trajectory files, click on the button.
video_track001.txt
- 229.62083 123.652084
- 237.8419 126.005714
- 254.4334 133.35347
- 261.40714 136.61786
- 269.62476 140.42857
- null
- null
- null
- null
- 276.33334 145.55933
- 281.40805 150.60919
- 285.1261 155.46892
- 290.2467 163.03955
Loading zones
Zones partitioning the area of investigation can be created using the Zone Designer module. Binary files (ATZ files) containing the zones can be loaded by clicking on the button. The names of loaded zones are listed in the .
To check the zones’ exact location within the recording, open the recording and click on the button. Thereafter, when selecting a zone in the , it will also appear in the image.
Setting parameters
Some sort of dimension (e.g. mm, cm; min, sec) is designated to most parameters, which in certain cases necessitates the definition of a conversion number between these dimensions and those of the recording (e.g. FPS; pixel/unit ratio).
These settings can be changed by clicking on the button.
Pop-up windows display the names of the currently available parameters. By clicking on the button located beside the name of the given parameter, a new window appears where settings can be changed – the window can differ from parameter to parameter.
Distance Parameter dialog
The unit of measurement of distance and the pixel/unit ratio can be set.
Time Parameter dialog
Time intervals between frames can be set. E.g. in case of 15 FPS this value would be 1/15 ≈ 0.067 sec.
Immobility Parameter dialog
This parameter serves to measure the duration of time the tracked object spends in a motionless state. In case the tracked object covers a distance (in pixels) less than that of the set value within a given number of frames, the program considers it to be immobile.
Setting zones
It is possible to set which parameters to extract from each zone. The row(s) the user wishes to modify must be selected in the of zones (more than one row can be selected at the same time) and the button should be clicked.
The list of available will be displayed in the pop-up window. By ticking the appropriate beside the listed parameters, the form the data is to be extracted in can be designated.
If this option is chosen, calculated values appertaining to all frames are extracted.
The output is the sum of the measured values.
The output is the mean of measured values.
The output is the standard deviation of measured values.
The output is the highest value among measured values.
The output is the lowest value among measured values.
Show results
Results are displayed upon clicking . It is possible to select whether the results should be displayed per zone or per parameter in the appearing window. The results, appearing in the results tables of ImageJ, can then easily be saved as text files or copied.
