Tutorial / Processing image series

Open an image in UVMAT_DEMO03_PIVchallenge_2005C, representing a jet seeded by particles (accessible on ​http://servforge.legi.grenoble-inp.fr/pub/soft-uvmat/).

The series contains 99 image pairs, labelled by a number with 3 digits and a letter index a and b. The nomenclature type [NomType], given as the first image index, is therefore '001a'. Activate the menu bar option [Run/field series] to open the new GUI series.

This GUI is used to launch various processing programs on field series. The program name is selected in the menu [ActionName]. The default option 'check_data_files' just list the set of input files and checks their existence and type.

The lower and upper indices for the input field series are given by first_i, last_i, and first_j, first_j for the second index a~1 and b~2, with an increment incr_i and incr_j for each index. The min and max indices in the series are given by the tables [!MinIndex_i], [!MaxIndex_i], [!MinIndex_j], [!MaxIndex_j]. As an example, set first_i=50, last_i=100, incr_i=10, first_j=1, last_j=2, incr_j=1. Pressing [RUN], the function 'check_data_files' is activated and yields the list of file names, with the two last ones, c100a.png and c100b.png, marked as not found.

Aver_stat, simple field average

This function provides field average or global statistics on the whole input file series. Let us set first_i=1,last_i=99, incr_i=1. Then run 'aver_stat'. The average image is displayed and stored as Images.stat/c001ab.png.

Aver_stat, global statistics

Other statistics can be obtained by aver_stat using a projection object. To create an object, go back to uvmat. Then check Projection object (tag = [CheckObject]) in series.

Time_series

This function provides the image intensity at a set of points versus time. First define the set of points as a projection object, using uvmat. Once you run the function, the GUI get_field appears (as well as the Figure1) where you can select the coordinates of the figure.

Data organisation

Functions from series store results in files (except 'check_data_files'), so you need writing access on the data directory. An alternative possibility is to create a mirror directory using symbolic links so that the folders of the original images remains unperturbed.

To create such a mirror, first open the images with the menu bar option [Open campaign/browse...] (instead of [Open/browse...]). Press the browser button [SELECT] when the camppaign .../UVMAT_DEMO_FILES appears in the upper window [titlebox] of the browser (then the list of subfolders appears in the main window [list]. This opens a new GUI browse_data. Each example folder is then considered as an 'Experiment', and their subfolders are 'DataSeries'. To create a mirror, press [create_mirror] and set the path to the mirror folder to be created. Then select an 'Experiment' and a 'DataSeries' to open by uvmat.

At the next opening you can directly open the mirror folder.