What it means
Older OCR engines segmented the plate into single characters and matched each one against templates. Current ANPR systems use neural networks that read the whole plate as a sequence, which copes better with uneven spacing, dirt and perspective. Most systems also check the result against the plate format rules of the country, so that a read with an impossible state code is flagged.
How it applies in India
Indian plates challenge OCR in specific ways: two-line and three-line layouts on two-wheelers and commercial vehicles, hand-painted fonts, decorative fonts on older plates, stickers and dirt, and confusions such as 0 and O, 8 and B, or 1 and I. HSRP plates use a standard font, which helps. Ask a vendor how the model was trained on Indian plates, and how the read rate is defined: the whole plate correct, or individual characters correct. Those are different numbers.