To make our integrated platform accessible to all users regardless of computational background, we derived a simple user interface for automated analysis of swimming movies (Figure 3). After defining the location of a family of sequentially named .tif images (multiple independent recordings can be analyzed and summary statistics are reported), the acquisition parameters (i.e., spatial resolution (µ/pixel) and recording speed (frames per second) are entered (Figure 3a). Users can adjust body and skeleton threshold values to obtain the best fit to their recording conditions (Figure 3b). After definition, users see the progress of analysis, including summary kinematics, biomechanics, skeletonization, and curvature plots (Figure 3c). Upon completion of the analysis, summary statistics for each of the 18 parameters are shown (Figure 3d) and users can review each individual recording for accuracy using trajectory plots, curvature analysis, and/or a skeleton browser. Data are output as .txt files for further analysis.
We have developed a free, user-friendly, and quantitative solution for integrative analysis of C. elegans locomotion. Our method uses equipment commonly found in C. elegans research labs, making it easy and inexpensive to implement. The ability to quantitatively analyze phenotypes regardless of image acquisition methods should allow comparison of data between laboratories. Full manuscript, BMP MATLAB scripts as well as detailed instructions and sample files (Krajacic et al., 2012) are available for download at www.genetics.org.
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