Real-time line scan processor

• US 5,434,629 A
• Filed: 12/20/1993
• Issued: 07/18/1995
• Est. Priority Date: 12/20/1993
• Status: Expired due to Term

• Current Assignee: SBS Technologies Incorporated (General Electric Company)
• Original Assignee: Focus Automation Systems, Inc.
• Inventors: Houde, Jacques S., Merchant, David B., Wardell, Mark B., Burjoski, Joseph D., Lammers, Scott G., Strauss, Ronald E., Pearson, Eric C., Pawelko, Thomas P.
• Primary Examiner(s): Chin, Tommy P.
• Assistant Examiner(s): Le, Vu
• Application Number:
  US08/169,665
• Time in Patent Office: 575 Days
• Field of Search: 348/88, 348/135, 348/719, 348/720, 348/721, 382/27, 382/28, 382/49
• US Class Current: 348/721
• CPC Class Codes: G06T 1/20 Processor architectures; Processor configuration, e.g. pipelining

Abstract

A processor comprises a plurality of parallel channels having an upstream end and a downstream end, Each channel comprises a video data bus for continuously transferring video data from the upstream end to the downstream end, a plurality of modules serially connected along the video data bus and a host computer connected to the downstream end of the plurality of channels for receiving the video data. Each module comprises a crossbar switch, a pixel processing element connected to the crossbar switch, a delay resource connected across the crossbar switch and a microprocessor operably integrated within each module for controlling the operation thereof. The microprocessors of each module are serially connected together for transmitting and undertaking commands. The host computer is also connected to the microprocessor of each module for issuing commands for controlling the operation of the processor. The processor is capable of receiving video data from at least one line scan sensor and sequentially processes the video data to manipulate a high resolution image of an object moving relative to the at least one line scan camera.

Claims

1. A processor for continuously processing video data of an object moving relative to at least one line scan sensor to extract features and measurements of the object and outputting said features and measurements to a host computer, said processor comprising:

a plurality of parallel channels having an upstream end and a downstream end, each of said channels comprising;

a pipeline video data bus for continuously receiving video data at the upstream end and transferring the video data to the downstream end,

a plurality of modules connected along the pipeline video data bus, each module of said plurality of modules comprising;

a crossbar switch connected to the pipeline video bus, said crossbar switch directing the video data into, within and out of said module,

a pixel processing element connected to the crossbar switch, said pixel processing element performing a continuous operation on said video data for extracting features and measurements therefrom,

a microprocessor operably integrated within each module for controlling the operation thereof,

each microprocessor of said plurality of modules serially connected together for transmitting and undertaking commands issued by a host computer for controlling the operation of said processor.

2. A processor as claimed in claim 1 wherein said crossbar switch of each module comprises a first input connected to the video bus for receiving video data from upstream thereof, a second input for receiving video data from within the module, a first output connected to the video bus for transferring video data downstream thereof and a second output for transferring video data to within the module.

3. A processor as claimed in claim 2 wherein each module of said plurality of modules includes a delay line and look-up table connected to said crossbar switch aligning said video data.

4. A processor as claimed in claim 3 wherein said look-up table line comprises a RAM memory and said delay line comprises a FIFO memory.

5. A processor as claimed in claim 4 wherein said plurality of modules includes a sensor module, wherein the pixel processing element thereof receives the video data from said at least one line scan sensor, normalizes the video data and transfers the video data to the video data bus.

6. A processor as claimed in claim 5 wherein said sensor module includes a video image generator connected to said crossbar switch and connectable to a video monitor, wherein said video generator receives a copy of the video data and transforms the video data to a video image output of the object.

7. A processor as claimed in claim 6 wherein said sensor module includes a sensor interface for synchronizing and controlling said at least one line scan sensor, an encoder interface for receiving an encoder signal proportional to the object moving relative to said at least one line scan sensor and transmitting said encoder signal to said sensor interface, said sensor interface generating a lamp control signal for regulating a lamp for illuminating the object and a sensor control signal for controlling said at least one line scan sensor, both said lamp control signal and sensor control signal responsive to the encoder signal.

8. A processor as claimed in claim 4 wherein said plurality of modules includes a look-up table module, wherein the pixel processing element of the look-up table module performs pixel transformations and histogram computations on the video data.

9. A processor as claimed in claim 8 wherein said pixel processing element of the look-up table module comprises an output connectable to a power source of a light source for illuminating said object, whereby the pixel processing element of said look-up table continuously undertakes said histogram computations and generates a signal for modulating said power source for maintaining a substantially constant light intensity illuminating said object.

10. A processor as claimed in claim 4 wherein said plurality of modules includes a buffer module, wherein the pixel processing element of the buffer module comprising a memory for storing a golden template image and said pixel processing element of the buffer module subtracts said golden template image from the video data for extracting a difference image.

11. A processor as claimed in claim 10 wherein said buffer module simultaneously processes at least two streams of video data.

12. A processor as claimed in claim 4 wherein said plurality of modules includes a blob module, wherein the pixel processing element of the blob module performs greyscale connectivity analysis on said difference image for extracting object descriptor information thereby extracting said features and measurements.

13. A processor as claimed in claim 12 wherein said blob module simultaneously processes at least two streams of video data.

14. A processor for manipulating video data of an image of an object moving relative to at least one line scan sensor and outputting information extracted from the video image to a host computer, said processor comprising:

a plurality of parallel channels having an upstream end and a downstream end, each of said channels comprising;

a video data bus for continuously transferring video data from the upstream end to the downstream end,

a plurality of modules serially connected along the video data bus, each module of said plurality of modules comprising;

a crossbar switch connected to the video bus, said crossbar switch directing video data into, within and out of said module,

a pixel processing element connected to the crossbar switch, said pixel processing element performing an operation on said video data,

a delay line and look-up table connected to said crossbar switch for aligning video data,

a microprocessor operably integrated within each module for controlling the operation thereof, said microprocessor of each module of said plurality of modules serially connected together for transmitting and undertaking commands;

said plurality of modules includes;

a sensor module for receiving the video data from said at least one line scan sensor and transferring the video data to the crossbar switch of the sensor module, said sensor module comprising

a sensor interface for synchronizing and controlling said at least one line scan sensor, an encoder interface for receiving an encoder signal proportional to the relative movement of the object and transmitting said encoder signal to said sensor interface, said sensor interface generating a lamp control signal for modulating a light source illuminating the object and a sensor control signal responsive to the encoder signal, said sensor control signal for controlling the operation of the at least one line scan sensor,

an offset circuit and a normalization circuit connected between the sensor interface and the crossbar switch, said offset circuit and normalization circuit for minimizing effects of background noise on the video data as the video data is transferred from the sensor interface to the crossbar switch, and

a video display generator connected to said crossbar switch and connectable to a video monitor, said video generator receives a copy of the video data and transforms the video data to a video display output;

a buffer module for storing a golden template image and template matching a high resolution image with said golden template image and generating a difference image,

a blob module for performing greyscale connectivity analysis on said difference image for extracting object descriptor information.

15. A processor as claimed in claim 14 wherein said plurality of modules further includes a look-up table module for performing pixel transformations and histogram computations on the video data, said look-up table module is connectable to a power source of the light source illuminating said object, whereby said look-up table continuously undertakes histogram computations and generates a signal for modulating the power source for maintaining a substantially constant light intensity illuminating said object.

16. A method of continuously processing video data of an object moving relative to at least one line scan sensor to extract features and measurements of the object, said method comprising the steps of:

synchronizing and controlling at least one line scan sensor generating a video image of the object comprising a stream of video data;

normalizing the stream of video data;

transferring the stream of video data to a video data bus;

comparing the stream of video data with a golden template image of the object and generating a difference image;

performing greyscale connectivity analysis on the difference image and extracting features and measurements;

outputting said features and measurements to a host computer.

17. A method as claimed in claim 16 wherein said method further includes a step of performing histogram computations on the stream video data and generating a signal for modulating a power source for a light source illuminating the object, maintaining a substantially constant light intensity illuminating said object.

18. A method as claimed in claim 16 wherein said method further includes transferring a copy of the stream of video data to a video generator and generating a video display of the object.

19. A method as claimed in claim 16 wherein said method simultaneously processes in parallel at least two streams of video data.

20. A method as claimed in claim 16 wherein said stream of video data is filtered prior to the step of comparing the stream of video data with said golden template image of the object and generating said difference image.