Embed Size (px)
Citation preview
APPENDIX - A. Image Processing Example A-1 Fixed Threshold ..................................................................................... 1 A-2 OCR DTC (Dynamic Threshold for OCR)............................................ 2
A-2.1 Ball Point Pen Fiter ............................................................................................. 2 A-2.2 Gradation............................................................................................................. 3 A-2.3 Threshold Table................................................................................................... 3 A-2.4 Noise Removal.................................................................................................... 4 A-2.5 Smoothing ........................................................................................................... 6
A-3 Form DTC (Dynamic Threshold for FORM) ........................................ 7 A-3.1 Sensitivity ........................................................................................................... 7 A-3.2 Threshold ............................................................................................................ 7
A-4 Dither....................................................................................................10 A-5 Minimize Average Error.......................................................................12 A-6 Random Dither .....................................................................................15 A-7 Filter .....................................................................................................17 *) Depending on the scanner yo
the sample image indicated in
P3PC-E087-02ENC2
u use or the document you scan, an actual scanning result may differ from this document.
Back to “Image Processing Software Option User’s Guide” >
1
A-1 Fixed Threshold
Original
Threshold = 192
Threshold = 128
Threshold = 64
User’s Guide →
2
A-2 OCR DTC (Dynamic Threshold for OCR) A-2.1 Ball Point Pen Fiter
Ball Point Pen Filter = OFF
Ball Point Pen Filter = ON
User’s Guide →
3
A-2.2 Gradation
A-2.3 Threshold Table
Gradation 0 Gradation 1 Gradation 2 Gradation 3
Threshold Table 0
Threshold Table 1
Threshold Table 2
Threshold Table 3
Threshold Table 4
Threshold Table 5
Threshold Table 6
Threshold Table 7
4
A-2.4 Noise Removal
Original (Noise Removal=OFF)
Noise Removal = 2x2 Noise Removal = 3x3
Noise Removal = 4x4 Noise Removal = 5x5
5
Noise Removal = 2x2
Noise Removal = 3x3
Noise Removal = 4x4
Noise Removal = 5x5
6
A-2.5 Smoothing
Smoothing = OFF
Smoothing = IMAGE
Smoothing = OCR
7
A-3 Form DTC (Dynamic Threshold for FORM) A-3.1 Sensitivity
A-3.2 Threshold
Sensitivity=0 (Threshold=128) Sensitivty=255 (Thr
Sensitivity=24, Threshold=128
(Sensitivity=24) Threshold=0 (Sensitivity=24) Thr
eshold=128)
eshold=255
User’s Guide →
8
Adjusting Sensitivity Default Sensitivity=24 is noisy. There are 2 ways to reduce noises.
1. Set higher value (ex. Sensitivity=32). Sensitivity is reduced but noises are reduced. 2. Use Average 3x3 Filter. Sharpness is lost but noises are reduced.
Sensitivity=32, Threshold=128
Sensitivity=24, Threshold=128
Sensitivity=24, Threshold=128 + Average 3x3
9
Adjusting Threshold Sensitivity is decided next to adjust the Threshold for background to be best suited.
Threshold=64
Threshold=128
Threshold=192
Using Average Filters In FORM processing, usually document condition are not good. Use of average filter is recommended. ‘Average 3x5 Filter’ is effective, if resolution is not required. ‘Average 3x3 Filter’ is effective, in typical cases.
Average 3x5 + FORM DTC (Sensitivity=24, Threshold=128)
Average 3x3 + FORM DTC (Sensitivity=24, Threshold=128)
10
A-4 Dither See also A-5 for “Adjusting Brightness”, “Adjusting Contrast”.
Dither 0
Dither 1
Dither 2
Dither 3
User’s Guide →
11
Dither 0 Dither 1
Dither 2 Dither 3
12
A-5 Minimize Average Error
MINIMIZE AVERAGE ERROR
User’s Guide →
13
Adjusting Brightness
Brightness=64 Brightness=192
Brightness=128
14
Adjusting Contrast
Contrast=64 Contrast=192
Contrast=128
15
A-6 Random Dither See also A-5 for “Adjusting Brightness”, “Adjusting Contrast”.
Text Fine (2x2 Solid)
Photo Fine (8x8 Blight)
Text Fine (2x2 Solid) Photo Fine (8x8 B
light)
User’s Guide →
16
Adjusting Outline Detection Threshold
Outline Detection Threshold = 0 Outline Detection Threshold = 127
A-7 Filter
User’s Guide →
17
Emphasis 3x3
Original (Threshold=128)
Average 3x3
Average 3x5
