DLC Re-Builder: Sketch Based Recognition and 2-D Conversion of Digital Logic Circuit Maitreyi Sharma, Sonal Nipane, Rachita, Krupa N. Jariwala, and Rasika Khade (B) Sardar Vallabhbhai National Institute of Technology, Surat, India rasika.khandre@gmail.com http://www.svnit.ac.in Abstract. Sketch owing to its ability to convey ideas and ease of cre- ation has found application in almost all spheres. From client presen- tations to documentations, sketching is ideal for conveying thoughts. Sketching of initial ideas or drafts for brainstorming sessions is a com- mon practice. However, these rough sketches require remodelling to a for- mal format, which adds an overhead to the process. Thus, arises a need to efficiently create, store and update hand-drawn sketches. Computer interfaces for sketching, that can augment the process by maintaining fair drafts, recognizing objects in the sketch, analyzing and summarizing the sketch and more, have been developed. A system that does similar pro- cessing for logic circuits is aimed. The complete application is designed optimally to give an accuracy of 89.41% using R-CNN and 82.44% using YOLO. DLC Re-builder(Digital Logic Circuit Re-builder) is a sys- tem that would accept sketched logic circuits as input, recognize various components of the circuit and convert the sketch-based circuit into for- mal graphical format. It would also generate a boolean expression for the final reconstructed 2-D output along with the truth table. Keywords: Object detection · Deep learning · Sketch-based image · YOLO · R-CNN (Region-based Convolutional Neural Network) · Corner detection · Circuit reconstruction · Boolean expression 1 Introduction A sketch is any handwritten text, image or a freehand drawing used to illustrate an idea or thought quickly and efficiently. Sketching is not restricted to a certain field of study and happens to be a natural form of human communication which has led to its increasing popularity as a tool for interaction with user interfaces [6]. Recognition of sketch-based images, curves and drawings has found many applications owing to the ease with which a sketch can be drawn and its ability to demonstrate any abstract object, idea or a real-life problem [4]. A sketch can be used as an alternative to the finished drawings when cre- ated with online editors for structured and unstructured diagrams. Structured c  Springer Nature Singapore Pte Ltd. 2021 D. Garg et al. (Eds.): IACC 2020, CCIS 1368, pp. 200–214, 2021. https://doi.org/10.1007/978-981-16-0404-1_15