Understanding Scanners/Monochrome images and Optical Character Recognition (OCR) | Index | Home |
OCR generates noise around text |
Image with much noise in the vicinity of the letters |
This is caused by an exceedingly high threshold value hindering the import of the text and can be corrected by lowering the monochromatic threshold level and re-scanning. |
Lowering the threshold value too much will cause the letters to appear dim. |
Setting the monochrome threshold lower |
The noise has been reduced |
The appearance of the image can be improved with image editing software. After scanning with 256-color gray scale, use the tone curve and nonlinear (gamma) correcting feature to clean the background while leaving the text clear. |
Compare:Understanding Scanners/Text appears dim when using OCR |