DEV Community

Cover image for Barcode and QR detection in noisy real-world images: what actually helps
PRANJUL RATHOUR
PRANJUL RATHOUR

Posted on Originally published at pranjulrathour.scult.in

Barcode and QR detection in noisy real-world images: what actually helps

#vision #barcodedetection #robustness

A barcode or QR scanner tested on a clean printed sample works reliably. The same code, crumpled, poorly lit, or photographed at an angle on a real receipt, fails far more often — and that's the condition it actually needs to work in.

What actually helps

  • Preprocessing: adaptive thresholding and deskewing before detection, rather than feeding the raw photo directly to a decoder.
  • Trying multiple crop regions and rotations if the first detection attempt fails, rather than giving up after one pass.
  • Falling back to a larger, more robust detection library rather than a minimal one if your first choice struggles on real-world samples.

Testing honestly

Build your test set from real photos taken the way users will actually take them — hand-held, imperfect lighting — not from clean scanned samples, which will always overstate real-world performance.

See camera-quality problems that quietly break a vision model.

About Pranjul Rathour

Pranjul Rathour pitching with a microphone in front of a projector slide at CSJMU, Kanpur
Pitching at CSJMU, Kanpur

Pranjul Rathour speaking from the podium at VSICS, Kanpur
At the VSICS podium, Kanpur

Pranjul Rathour holding a trophy and a certificate of merit after a win
Trophy and certificate after a win

Pranjul Rathour presenting evaluation criteria — feasibility, innovation, practicality, problem solving — on a projector screen
Walking a room through evaluation criteria

Pranjul Rathour presenting BrandHive on a projector screen
Presenting BrandHive

Pranjul Rathour is a GenAI engineer from Kanpur, India, and CTO at SCULT INDIA, currently shipping production RAG,
fine-tuning and agentic AI systems, mentoring 200+ students through TechVerse Enclave, and judging and speaking at
student hackathons across India. Updated 2026-09-11.

Reach out if you want to talk GenAI, book a campus session, or invite him to judge:

Pranjul Rathour · GenAI engineer, 3x hackathon winner, campus mentor. Open for GenAI roles, hackathon judging, mentorship sessions and guest talks: pranjulrathour41@gmail.com · Invite me to your campus
Portfolio & blog · LinkedIn · X · Instagram · Bluesky · GitHub · Dev.to

Top comments (0)