A new data transfer method via signal-rich-art code images captured by mobile devices Source: IEEE Transactions on Circuits and Systems for Video Technology, Vol. 25, No. 4, pp. 688-700, 2015. Authors: Lee Ya-Lin, Tsai Wen-Hsiang Speaker: Huang Peng-Cheng Date: 11/9/2018

Outline Introduction Proposed Scheme Experiment Results Conclustion

Introduction(1/2) What is the signal rich art using for? Exchange the information The techniques for signal-rich-art communication Barcodes (1-D barcode, QR code, PDF417, Data matrix code) Data hiding (watermarking)

Introduction(2/2)

Proposed Scheme(1/12) Major steps of two phases of proposed method

Proposed Scheme(2/12). 1. Generation of Signal-Rich-Art Code Image. A Proposed Scheme(2/12) 1. Generation of Signal-Rich-Art Code Image A. Pattern Image Creation(1/2)

Proposed Scheme(3/12). 1. Generation of Signal-Rich-Art Code Image. A Proposed Scheme(3/12) 1. Generation of Signal-Rich-Art Code Image A. Pattern Image Creation(2/2)

Proposed Scheme(4/12). 1. Generation of Signal-Rich-Art Code Image. B Proposed Scheme(4/12) 1. Generation of Signal-Rich-Art Code Image B. Block Luminance Modulation (1/3) NB, Nw Ti Sort Bi q1' q2' q3' q4' q5' q6' q7' q8' q9' q10' q11' q12' q13' q14' q15' q16' e.g. T4 NB=4, Nw=12 Sort 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16

Proposed Scheme(5/12). 1. Generation of Signal-Rich-Art Code Image. B Proposed Scheme(5/12) 1. Generation of Signal-Rich-Art Code Image B. Block Luminance Modulation (2/3) = 1 4 1+2+3+4 = 1 12 5+…+16

Proposed Scheme(6/12). 1. Generation of Signal-Rich-Art Code Image. B Proposed Scheme(6/12) 1. Generation of Signal-Rich-Art Code Image B. Block Luminance Modulation (3/3)

Proposed Scheme(7/12). 2. Message Extraction. A Proposed Scheme(7/12) 2. Message Extraction A. Localization of Signal-Rich-Art Code Image and Inverse Perspective Transform(1/1)

Proposed Scheme(8/12). 2. Message Extraction. B Proposed Scheme(8/12) 2. Message Extraction B. Block Number Identification and Block Segmentation (1/2) (1)Compute the gradient value of each pixel. (3) Find the candidate splitting lines (2)guess the number NS of unit blocks in the horizontal or vertical direction (4) Find the largest nj which get the close to the largest AGnj, as the desired number Ns. Where L is the side length of the capture image

Proposed Scheme(9/12). 2. Message Extraction. B Proposed Scheme(9/12) 2. Message Extraction B. Block Number Identification and Block Segmentation (2/2)

Proposed Scheme(10/12). 2. Message Extraction. C Proposed Scheme(10/12) 2. Message Extraction C. Binarization and Recognition of Pattern Blocks(1/3) (1) Binarize the image using Moment-preserving threshold technique (2) Calculate the feature of the black for each block 𝑏𝑓 𝑘𝑗 = 1, 𝑤ℎ𝑒𝑛 𝑡ℎ𝑒 𝑢𝑛𝑖𝑡 𝑏𝑙𝑜𝑐𝑘 𝑖𝑠 𝑏𝑙𝑎𝑐𝑘 0, 𝑤ℎ𝑒𝑛 𝑡ℎ𝑒 𝑢𝑛𝑖𝑡 𝑏𝑙𝑜𝑐𝑘 𝑖𝑠 𝑤ℎ𝑖𝑡𝑒 For code pattern For pattern block (3) Find out the minimum absolute distance between the object with eight code pattern

Proposed Scheme(11/12). 2. Message Extraction. C Proposed Scheme(11/12) 2. Message Extraction C. Binarization and Recognition of Pattern Blocks(2/3) Suppose that

Proposed Scheme(12/12). 2. Message Extraction. C Proposed Scheme(12/12) 2. Message Extraction C. Binarization and Recognition of Pattern Blocks(3/3)

Experiment Results(1/7)

Experiment Results(2/7)

Experiment Results(3/7) the metric of mean structural similarity (MSSIM)

Experiment Results(4/7)

Experiment Results(5/7)

Experiment Results(6/7)

Experiment Results(7/7)

Conclusion a better visual appearance the message data extraction accuracy is higher the data extraction speed is higher