输入：CSV格式的RSSI数据

For each row 'i' from 0 to 19936:

Reshape first 520 elements of row 'i' of 'a' into a 26 × 20 matrix, assign to D(i).e

Display D(i).e in grayscale

Adjust image to remove borders and axes, set size to 163.84x163.84

Save image to "D:\wen\UJIndoorLoc\final_files\train\", file name derived from elements 521-523 of row 'i' in 'a', format.jpg

End For