Video process control apparatus

• US 4,400,728 A
• Filed: 02/24/1981
• Issued: 08/23/1983
• Est. Priority Date: 02/24/1981
• Status: Expired due to Fees

• Current Assignee: Everett Charles Test Equipment
• Original Assignee: Everett/Charles Incorporated
• Inventors: Long, David J.
• Primary Examiner(s): Bookbinder, Marc E.
• Assistant Examiner(s): Coles, Edward L.
• Application Number:
  US06/237,689
• Time in Patent Office: 910 Days
• Field of Search: 358/93, 358/107, 358/903, 364/515, 364/516, 364/517, 340/146.3 H, 340/146.3 Q
• US Class Current: 348/138
• CPC Class Codes: G01B 11/024 by means of diode-array scanning
• CPC Class Codes: G06T 7/60 Analysis of geometric attributes

Abstract

A video process control system for identifying, inspecting, or measuring machined parts or the like in which each part is placed in the viewing field of a video camera. A pixel scan of the camera image is converted to a set of binary bits, one bit for pixel, and the bits corresponding to one complete frame are stored in a frame memory. A plurality of digital control words stored in a memory each define a selected area or "window" in the field of view a predetermined number of bits of one value. Each word in memory is used to select a group of the stored pixel bits corresponding to the defined window. A counter counts the number of bits of one value in the select group, and their count is compared with desired number of bits defined by the same control word. The analysis is repeated for a plurality of the control words to get a complete measurement of a part.

Claims

1. Video process control apparatus comprising video camera means including raster scan means for generating a video output signal of the image field of the camera, means dividing the video signal into a series of pixels, means converting each pixel to a binary bit whose value indicates whether the amplitude of the video signal is above or below a predetermined threshold amplitude, frame memory means storing the bits converted from pixels forming one frame of the raster scan, digital memory means storing a plurality of digitally coded words, each word defining the margins of one predetermined window area within the image field of the camera, each word further defining the desired number of bits of one value corresponding to pixels within the defined area, means for reading out a selected full word at a time from the digital memory means, counter means, control means responsive to any selected word read out of said memory means for transferring all the bits of one value corresponding to pixels within the area defined by the selected word from the frame memory means to the counter, and means responsive to the selected word read out of said memory and the counter means for comparing the number of bits counted with the desired number of bits defined by said selected word.

2. The apparatus of claim 1 wherein said memory means stores words defining a range within upper and lower limits of the desired number of bits of one value within the defined area, said comparing means including means generating an output signal indicating when the counter means is within said range.

3. Apparatus of claim 2 further including means for reading out a plurality of said words in the memory means in sequence to the control means and the comparing means.

4. The apparatus of claim 3 further including means storing the output signals from said comparing means with each word read out of the memory means.

5. Apparatus of claim 4 further including video monitor means, means selectively or simultaneously responsive to said video signal output from the camera, the output of said means converting the pixels to binary bits, and the output of said frame memory means for driving the video monitor to form visual images from said outputs.

6. Apparatus of claim 5 further including means responsive to the selected word read out of memory defining a window for changing the image brightness on the monitor within the window area defined by said selected word.

7. Apparatus of claim 6 further including means for adjusting said threshold value of said means converting pixels to binary bits.

8. Apparatus of claim 1 wherein said digital memory means includes means for addressing and reading out each word in parallel.

9. Apparatus of claim 8 further including means for addressing and selectively writing in or reading out selected portions of each word.

10. Apparatus of claim 9 further including central processor means for selectively addressing each word or a portion of each word in the digital memory means.

11. Apparatus for visual analyzing assembly parts or the like comprising a video camera, pixel scan means for converting an image field of the camera into a stream of pixels, frame memory means storing the pixels corresponding to one pixel scan of the image field as corresponding number of binary bits, means responsive to each pixel for coding the bit to indicate when the pixel magnitude is above or below a predetermined threshold, window parameter memory means storing a plurality of digitally coded words, each word defining the addresses of bits in the frame memory means corresponding to pixels from a predetermined area of the image field, each word further defining a desired number of bits of one binary value associated with the area of the image field, means reading a selected word out of the window parameter memory, means responsive to each word read out of the window parameter memory means for addressing and reading out the bits stored in the frame memory from the addresses defined by said word, means counting the number of bits of one value read out of the frame memory means, and means comparing the number of bits counted with the desired number of bits defined by said word.

12. Apparatus of claim 11 wherein said means reading out a selected word out of the window parameter includes means for reading out a plurality of said words in sequence, each word separately addressing and reading out a different group of bits from the frame memory means.