How Bengali OCR Handles যুক্তবর্ণ and Handwriting

Scanning a Bengali exam script is harder than it looks. Bengali orthography uses over 300 conjunct characters (যুক্তবর্ণ) formed by combining base characters with hasanta. A single misread ligature can turn a correct answer into gibberish. E-Porikkha's OCR pipeline is built specifically to handle this.

When you upload a scan, the file is split into individual pages and each page is read by our OCR engine, tuned specifically for Bengali handwriting and mixed-script pages. It reads the page holistically — not character by character — which makes it far more robust to smudging, uneven ink pressure, and margin notes.

Pages are processed in parallel, so a 10-page script takes roughly the same time as a 2-page one.

Wherever the pipeline cannot confidently read a word — due to extreme smudging, torn paper, or very faint pencil — it outputs [illegible] rather than guessing. This is intentional and enforced end to end: the grading step is explicitly instructed never to invent an answer for a spot marked [illegible], and never to treat it as the student having skipped the question. A hallucinated Bengali word looks plausible but is wrong; [illegible] is honest and lets you decide.

You'll see [illegible] markers in the extracted text before you grade. The text is fully editable at that point, so you can correct any misread word yourself before grading runs.

Many science and maths papers mix Bengali prose with English technical terms, formulas, or numbers. The OCR model handles this natively — it preserves English words in their original script without transliteration.

Scan at 300 DPI or higher. JPEG compression at low quality settings blurs fine strokes. If your scanner exports PDF, keep it at the original resolution rather than re-saving as a low-quality image.

If a paper is consistently getting [illegible] in the same spot, check whether the physical page has a fold or shadow — repositioning the paper on the scanner almost always helps.