Distilling GRU with Data Augmentation for Unconstrained Handwritten Text Recognition

Transcription

1 Disilling GRU wih Daa Augmenaion for Unconsrained Handwrien Tex Recogniion Reporer: Zecheng Xie Souh China Universiy of Technology Augus 6,2018

2 Ouline Problem Definiion Daa Augmenaion Experimens Conclusion Problem Definiion 2

3 Ouline Problem Definiion Daa Augmenaion Experimens Conclusion Problem Definiion 3

4 Moivaion Problem Definiion Handwrien exs wih various syles, such as horizonal, overlapping, verical, and muli-lines exs, are commonly observed in he communiy Mos exising handwriing recogniion mehods only concenrae on one specific kind of ex syle The new unconsrained online handwrien ex recogniion problem Problem Definiion 4

5 Problem Definiion The New Unconsrained OHCTR Problem Horizonal Verical Overlap Righ-Down Overlap Screw-Roaion Righ-Down Crew-Roaion Muli-line Problem Definiion 5

6 Novel Perspecive Problem Definiion Why no focusing on he variaion beween adjacen poins [14,15] More sable han he pen-ip coordinae disribue beween a specific bound for mos siuaions The unconsrained ex of muliple syles share a very similar feaure paern, he only difference beween differen ex syles is he pen-ip movemen beween characers [14] X Zhang, e al Drawing and recognizing Chinese characers wih recurren neural nework, IEEE ransacions on paern analysis and machine inelligence, 2018 [15] L Sun, e al Deep lsm neworks for online Chinese handwriing recogniion, in ICFHR 2016 Problem Definiion 6

7 Ouline Problem Definiion Daa Augmenaion Experimens Conclusion Problem Definiion 7

8 Feaure Exracion (x, y ) i-h sroke Feaure Exracion Online Tex Sampling Poins Pen-ip Movemen Pen down\up sae

9 Disilling GRU GRU can only oupu feaure sequence wih he same ime sep as ha of he inpu daa - grealy burden he framework if direcly applied in ex recogniion problem How o accelerae he raining process while no sacrifice performance 9

10 Disilling GRU 1-1- ReLU -1 h = (h 1, h,, h T ) h = (h 1, h,, h T/N ) hidden sae inpu

11 Disilling GRU Unlike he radiional pooling layer, our disilling operaion does no lose informaion from he GRU oupu 1-1- Accelerae he raining process while no sacrifice any performance ReLU hidden sae inpu

12 Transcripion blank 观 期 π :_ 备 _ 受 _ 观观 _ 众 _ 期期 _ 待 _ π :_ 备 _ 受 _ 观 _ 众 _ 期 _ 待 π :_ 备 _ 受 _ 观 _ 众 _ 期期期 _ 待 P l s = B 备受观众期待 π:b π =l P (π s) 12

13 h = (h 1, h,, h T/N ) 13

14 Ouline Problem Definiion Daa Augmenaion Experimens Conclusion Problem Definiion 14

15 Daa Augmenaion Horizonal Verical Overlapping Muli-lines Screw roaion Righ-down Δ i, Δ i : pen movemen beween he i and i + 1-h characers imin, i ma :he minimum and maximum x-coordinae value of he i-h characer f i, l i : he x-coordinae values of he firs and las poins of he i-h characer Δ r :a random bias generaed from an even disribuion beween (-2, 13) Δ line :ex line lengh ha can be adjused according o pracical siuaion All he abovemenioned definiions also apply for he Y- axis Daa Augmenaion 15

16 Ouline Problem Definiion Daa Augmenaion Experimens Conclusion Problem Definiion 16

17 Experimens Training Daa CASIA-OLHWDB20-22 [1] Synheic Unconsrained Daa by CASIA-OLHWDB10-12 [1] Tesing Daa ICDAR2013 Tes Daase [2] Synheic Unconsrained Daa by CASIA-OLHWDB10-12 [1] Nework 2-Layers Disilling GRU,Disilling Rae=025 Hardware GeForce Tian-X GPU Convergence ime 208h 95h [1] C Liu, e al, CASIA online and offline Chinese handwriing daabases, 2011 Inernaional Conference on Documen Analysis and Recogniion (ICDAR), pp 37 41, 2011 [2] Yin F, e al, ICDAR 2013 Chinese handwriing recogniion compeiion, ICDAR2013, pp Experimens 17

18 Experimens Experimens 18

19 Experimens [3] X Zhou, e al, IEEE TPAMI, vol 35, no 10, pp , 2013 [4] X Zhou, e al, Paern Recogniion[J], 2014, 47(5): [29] Z Xie, e al, IEEE TPAMI, 2017 [30] K Chen, e al, in ICDAR 2017, vol 1 IEEE, 2017, pp Experimens 19

20 Demo Experimens Experimens 20

21 Conclusion The new unconsrained ex recogniion problem is suggesed o advance he handwrien ex recogniion communiy A special perspecive of he pen-ip rajecory is suggesed o reduce he difference beween exs of muliple syles A new daa augmenaion mehod is developed o synhesize unconsrained handwrien exs of muliple syles A Muli-layer disilling GRU is proposed o process he inpu daa in a sequenial manner Achieves sae-of-he-ar resuls on ICDAR2013 ex compeiion daase bu also shows robus performance on our synhesized handwrien es ses Conclusion 21

22 Q & A Thank you! Lianwen Jin( 金连文 ), PhD, Professor eelwjin@scueducn lianwenjin@gmailcom Zecheng Xie( 谢泽澄 ), PhD, suden Manfei Liu( 刘曼飞 ), Maser, suden hp://wwwhcii-labne/ Experimens 22