Apparatus for enhancing and thresholding scanned microfilm image

Facsimile and static presentation processing – Facsimile – Specific signal processing circuitry

Patent

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

358466, H04N 140

Patent

active

049822942

ABSTRACT:
Apparatus for enhancing and thresholding scanned microfilm images, specifically for removing single pixel noise therefrom, and accompanying methods for use therein are disclosed. Specifically, this apparatus convolves each one of a pre-defined group of incoming pixel values with a corresponding one of a pre-defined set of coefficients in order to generate an convolved pixel value. The convolved pixel is then compared against a threshold level to produce a thresholded pixel value indicative of the results of the comparison. The inventive apparatus also includes a noise processing circuit that contains a noise tracker and a noise detector and filter circuit. The noise tracker is used to produce a noise value that tracks a noise level present in the threshold pixel value. The noise detector and filter circuit filters pixel noise from the thresholded pixel value and, in response thereto, produces a corresponding output pixel value for a current incoming pixel value being processed and provides a signal to the noise tracker that pixel noise has been detected. A background tracker, which also forms part of the inventive apparatus, produces a background value that tracks a background level present in the incoming pixel values. The background value and the noise value are combined to produce an error signal which, in turn, is used, along with a deaveraged value of the current incoming pixel value, to set the threshold level for the current pixel value being processed. Specific apparatus for the background tracker and the noise tracker, and accompanying methods for use therein, are also disclosed herein.

REFERENCES:
patent: 2855513 (1958-10-01), Hamburgen et al.
patent: 3394222 (1968-07-01), Townsend
patent: 3443026 (1969-05-01), Townsend
patent: 3472958 (1969-10-01), Estock
patent: 3515803 (1970-06-01), Lorang
patent: 3737854 (1973-06-01), Klemt
patent: 3737855 (1973-06-01), Cutaia
patent: 3800078 (1974-03-01), Cochran et al.
patent: 4162481 (1979-07-01), DuVall
patent: 4194221 (1980-03-01), Stoffel
patent: 4258394 (1981-03-01), Kennedy
patent: 4272789 (1981-06-01), Biron
patent: 4345314 (1972-08-01), Melamud et al.
patent: 4351004 (1982-09-01), Choate et al.
patent: 4389677 (1983-06-01), Rushby et al.
patent: 4400738 (1983-08-01), Tomory et al.
patent: 4408343 (1983-10-01), Neill et al.
patent: 4430748 (1984-02-01), Tuhro et al.
patent: 4442544 (1984-04-01), Moreland
patent: 4468704 (1984-08-01), Stoffel et al.
patent: 4473847 (1984-09-01), Kurata
patent: 4491964 (1985-01-01), Sanner
patent: 4501016 (1985-02-01), Persoon et al.
patent: 4506382 (1985-03-01), Hada et al.
patent: 4520505 (1985-05-01), Yamamoto et al.
patent: 4532548 (1985-07-01), Zwirn
patent: 4539600 (1985-09-01), Takahashi et al.
patent: 4547711 (1985-10-01), Ochi et al.
patent: 4550435 (1985-10-01), Hayman
patent: 4554593 (1985-11-01), Fox et al.
patent: 4561104 (1985-12-01), Martin
patent: 4562470 (1985-12-01), Dinh et al.
patent: 4562486 (1985-12-01), Suzuki et al.
patent: 4570186 (1986-02-01), Kurata
patent: 4571573 (1986-02-01), Tadauchi et al.
patent: 4573070 (1986-02-01), Cooper
patent: 4573075 (1986-02-01), Bolger
patent: 4575768 (1986-03-01), Sakai et al.
patent: 4577235 (1986-03-01), Kannapell et al.
patent: 4584703 (1986-04-01), Hallberg
patent: 4593325 (1986-06-01), Kannapell et al.
patent: 4594733 (1986-06-01), Kanzaki et al.
patent: 4613986 (1986-09-01), Ataman et al.
patent: 4625330 (1986-11-01), Higgins
patent: 4636863 (1987-01-01), Kaizaki et al.
patent: 4672461 (1987-06-01), Yoshida
patent: 4674126 (1987-06-01), Kotera
patent: 4675909 (1987-06-01), Egami et al.
patent: 4691366 (1987-09-01), Fenster et al.
Penny, R. E. "Dynamic Threshold Setting Circuit" IBM Technical Disclosure vol. 18 No. 6 11/75 pp. 1962-1965.

LandOfFree

Say what you really think

Search LandOfFree.com for the USA inventors and patents. Rate them and share your experience with other people.

Rating

Apparatus for enhancing and thresholding scanned microfilm image does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Apparatus for enhancing and thresholding scanned microfilm image, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Apparatus for enhancing and thresholding scanned microfilm image will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFUS-PAI-O-2000898

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.