Once a synchronized average waveform has been computed for each electrode position in the grid, the overall 2d signal across the surface of the chest can be computed and animated. Here is an example of using the component software to assemble 25 different EKG signals into a 5x5 2d grid, and then to time-slice through that grid of data to produce a set of 2d datasets which can then be displayed and animated as a surface or an image.
All 25 signals gave been synchronized about the R peak of the EKG waveform. Here are surface and image plots of the R peak for all 25 sensors. This peak comes 1/4 second (64 points out of 256) into each of the 25 signals. The bottom 2 plots are scaled for the RS peak extrema, while the top 2 are scaled for the later T peak extrema. The slider can be freely moved to make the displays update, or it can be set to automatically step through a predefined range of values creating an animation of all displays.
Here is the overall minimum of the S peak for all 25 signals:
Here are two small QuickTime movies of an animation of the surface and image plots of the RS subset of the data shown above. These movies should play OK inline on the page, or you can download them and play them outside the browser. Each movie is only 25 frames at 4 fps, so you may want to use loop mode in your movie player.
Here is a surface and image of the T "wave" maximum:
Here is a surface and image of the T "wave" minimum. Note that in this dataset the T "wave" is biphasic for most of the electrode signals:
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