TY - JOUR
T1 - Hardcopy image barcodes via block-error diffusion
AU - Damera-Venkata, Niranjan
AU - Yen, Jonathan
AU - Monga, Vishal
AU - Evans, Brian L.
N1 - Funding Information:
Manuscript received July 21, 2003; revised November 23, 2004. N. Damera-Venkata and B. L. Evans were supported by the U.S. National Science Foundation CAREER Award under Grant MIP-9702707. N. Damera-Venkata conducted some of this research while at The University of Texas, Austin. The associate editor coordinating the review of this manuscript and approving it for publication was Dr. Reiner Eschbach.
PY - 2005/12
Y1 - 2005/12
N2 - Error diffusion halftoning is a popular method of producing frequency modulated (FM) halftones for printing and display. FM halftoning fixes the dot size (e.g., to one pixel in conventional error diffusion) and varies the dot frequency according to the intensity of the original grayscale image. We generalize error diffusion to produce FM halftones with user-controlled dot size and shape by using block quantization and block filtering. As a key application, we show how block-error diffusion may be applied to embed information in hardcopy using dot shape modulation. We enable the encoding and subsequent decoding of information embedded in the hardcopy version of continuous-tone base images. The encoding-decoding process is modeled by robust data transmission through a noisy print-scan channel that is explicitly modeled. We refer to the encoded printed version as an image barcode due to its high information capacity that differentiates it from common hardcopy watermarks. The encoding/halftoning strategy is based on a modified version of block-error diffusion. Encoder stability, image quality versus information capacity tradeoffs, and decoding issues with and without explicit knowledge of the base image are discussed.
AB - Error diffusion halftoning is a popular method of producing frequency modulated (FM) halftones for printing and display. FM halftoning fixes the dot size (e.g., to one pixel in conventional error diffusion) and varies the dot frequency according to the intensity of the original grayscale image. We generalize error diffusion to produce FM halftones with user-controlled dot size and shape by using block quantization and block filtering. As a key application, we show how block-error diffusion may be applied to embed information in hardcopy using dot shape modulation. We enable the encoding and subsequent decoding of information embedded in the hardcopy version of continuous-tone base images. The encoding-decoding process is modeled by robust data transmission through a noisy print-scan channel that is explicitly modeled. We refer to the encoded printed version as an image barcode due to its high information capacity that differentiates it from common hardcopy watermarks. The encoding/halftoning strategy is based on a modified version of block-error diffusion. Encoder stability, image quality versus information capacity tradeoffs, and decoding issues with and without explicit knowledge of the base image are discussed.
UR - http://www.scopus.com/inward/record.url?scp=28844506126&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=28844506126&partnerID=8YFLogxK
U2 - 10.1109/TIP.2005.859776
DO - 10.1109/TIP.2005.859776
M3 - Article
C2 - 16370452
AN - SCOPUS:28844506126
SN - 1057-7149
VL - 14
SP - 1977
EP - 1989
JO - IEEE Transactions on Image Processing
JF - IEEE Transactions on Image Processing
IS - 12
ER -