Still working on implementing VAL. I had to make what felt like a significant decision regarding file formatting and variable declarations. You see the original bitmap formatted I wrote last summer rewrites text files as binary files with appropriate padding at the beginning of words. WAH is easy to reformat as you just add an extra 0 every 31 or 63 bits. However, with VAL, the segments can vary in length so I thought a lot about what the best way to format these files is. I eventually deciding to pad the segments every 7 bits since all of the lengths are divisible by 7. This also allows the compressor to read the file byte by byte and recreate the 14 and 28 bit segments of necessary by reading two or three bytes and then building a 14 or 28 bit segment respectively.
This also raised an issue regarding the type definition of a word. WAH 32 and WAH 64 both read and write 32 bit words. However, VAL reads by 8 bits but writes to 32 bits. The WAH engine I wrote uses the same type for both reading and writing so I had to add another type definition for reading and writing which would be the same for both WAH compressors but different for the VAL compressor.
This also raised an issue regarding the type definition of a word. WAH 32 and WAH 64 both read and write 32 bit words. However, VAL reads by 8 bits but writes to 32 bits. The WAH engine I wrote uses the same type for both reading and writing so I had to add another type definition for reading and writing which would be the same for both WAH compressors but different for the VAL compressor.
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