Improving performance with different length templates using both of correlation and absolute difference on similar play estimation - Emerging Trends in Image Processing, Computer Vision, and Pattern Recognition - page 406

point of the template ST-image. In the experiments, the lengths of the template ST-images are
15, 20, 25, 30, and 40. The F-measures are 0.818, 0.846, 0.849, 0.863, and 0.781 respectively.
Table 1 shows the relations between the performances and the length of templates using cor-
relation for calculating similarities. Using correlation for the similarity measure, the 40 frames
of length is too long for retrieving pitches in baseball games. Comparing the 30 frames of
length, the performance of the 40 is 10% lower than one of the 30.

Table 1
Performance with Correlation

Length Recall Precision F-Measure

15 0.809 0.828 0.818

20 0.845 0.847 0.846

25 0.821 0.879 0.849

30 0.887 0.840 0.863

40 0.803 0.760 0.781

Table 2 shows the relation between the performance and the starting point of 30 frames tem-
plate ST-images. In a range of six frames from 120125 to 120131, the F-measures keep over 0.84.

Table 2
Performance with Correlation by Starting Frame in 30 Frames Length Template ST Image

Starting Frame Recall Precision F-Measure

120115 0.565 0.646 0.602

120120 0.750 0.693 0.720

120125 0.892 0.799 0.842

120127 0.839 0.871 0.854

120129 0.887 0.840 0.863

120131 0.815 0.887 0.849

5.5 Absolute Difference Based Similarity Measure in Pitching
Retrieval
The length of durations of templates afects the performance a litle. In the experiments range,
the shortest one is the best one. The 15 frames length template retrieves all pitches. Moreover,
it is best in F-measure ( Table 3 ).