Document size conversion circuit for a document filing system

• US 4,468,755 A
• Filed: 10/30/1981
• Issued: 08/28/1984
• Est. Priority Date: 10/31/1980
• Status: Expired due to Term

• Current Assignee: Tokyo Shibaura Denki Kabushiki Kaisha
• Original Assignee: Tokyo Shibaura Denki Kabushiki Kaisha
• Inventors: Iida, Kazuhiko
• Primary Examiner(s): Smith, Jerry
• Assistant Examiner(s): Watson, Mark P.
• Application Number:
  US06/316,911
• Time in Patent Office: 1,033 Days
• Field of Search: 382/46, 382/47, 358/287, 364/200 MS File, 364/900 MS File
• US Class Current: 345/668
• CPC Class Codes: G06K 17/0016 Selecting or retrieving of images by means of their associated code-marks, e.g. coded microfilm or microfiche microfilm reading G03B21/11; computers therefor G06F16/00; teaching devices G09B5/02; accessing record carriers G11B27/002; static digital stores using optical elements G11C13/04; intermediate storage of facsimile picture signals H04N1/21
• CPC Class Codes: G06T 3/40 Scaling of whole images or parts thereof, e.g. expanding or contracting
• CPC Class Codes: H04N 1/2175 with local image input
• CPC Class Codes: H04N 1/2195 with temporary storage before final recording or on play-back, e.g. in a frame buffer
• CPC Class Codes: H04N 1/32512 of different type, e.g. internal and external devices
• CPC Class Codes: H04N 1/32529 of different type, e.g. internal and external devices
• CPC Class Codes: H04N 1/32561 using a programmed control device, e.g. a microprocessor
• CPC Class Codes: H04N 1/3875 combined with enlarging or reducing enlarging or reducing per se H04N1/393
• CPC Class Codes: H04N 2201/0081 Image reader H04N2201/0091 - H04N2201/0094 take precedence
• CPC Class Codes: H04N 2201/0082 Image hardcopy reproducer H04N2201/0091 - H04N2201/0094 take precedence
• CPC Class Codes: H04N 2201/0087 Image storage device
• CPC Class Codes: H04N 2201/0089 Image display device

Abstract

Picture information stored in a memory device is read out and written into a page buffer and visually displayed on the screen of a CRT display under control of an interface unit for display, through a size conversion circuit.

Claims

1. A document size conversion circuit for a document filing system comprising:

an information input terminal to which pieces of line picture information are supplied;

a plurality of memories each adapted to store one of said pieces of line picture information supplied to the terminal;

means for forming a matrix array of local picture information consisting of bits extracted from said plurality of memories;

means for obtaining a picture dot position in said matrix array of local picture information, the picture dot position corresponding to a size conversion rate;

means for obtaining an average gray level of said matrix array of local picture information with respect to said picture dot position; and

comparator means for comparing said average gray level and a predetermined slice level to form size converted data.

2. A document size conversion circuit according to claim 1, wherein said picture dot position obtaining means includes:

conversion rate setting data supplying means; and

X-direction and Y-direction distance calculating means for calculating an address designating signal from said size conversion rate setting data.

3. A document size conversion circuit according to claim 2, wherein said average gray level obtaining means includes arithmetic memory means for storing a plurality of average gray level data by using said address designating signal.

4. A document size conversion circuit according to claim 1, wherein said matrix array of local picture information forming means includes a plurality of latches for latching said bits extracted from said memories.