To improve the processing algorithm

[emilinecsa]

As described, the data extraction method occurs in two stages:

1. To run the old data extraction algorithm
2. To apply the new text recognition stage to read NUM2 metadata.

The algorithm should be refactored such that the metadata type can be detected initially, and then read according to its type. This refactoring and rebuilding of the code base could resolve certain long-standing issues and may improve yield. Furthermore, it can enable the algorithm to be more adaptable to be able to read Alouette-2, ISIS-1 and ISIS-2 ionograms.

[emilinecsa]

I recommend to modify the algorithm. This would be a significant improvement. In addition, this will make the code easier to read and to understand.