Electronic camera featuring single image processing

• US 5,543,835 A
• Filed: 12/12/1994
• Issued: 08/06/1996
• Est. Priority Date: 04/23/1990
• Status: Expired due to Fees

• Current Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Original Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Inventors: Mumura, Toshihiko
• Primary Examiner(s): Greening, Wendy R.
• Assistant Examiner(s): Shalwala, Bipin
• Application Number:
  US08/354,774
• Time in Patent Office: 603 Days
• Field of Search: 348/207, 348/362, 348/71, 348/626, 348/581, 364/724.01, 364/724.16
• US Class Current: 348/207.99
• CPC Class Codes: H04N 1/2104 for one or a few pictures
• CPC Class Codes: H04N 1/2112 using still video cameras
• CPC Class Codes: H04N 1/2137 with temporary storage before final recording, e.g. in a frame buffer
• CPC Class Codes: H04N 2101/00 Still video cameras
• CPC Class Codes: H04N 23/84 for processing colour signals
• CPC Class Codes: H04N 25/00 Circuitry of solid-state image sensors [SSIS]; Control thereof
• CPC Class Codes: H04N 25/60 Noise processing, e.g. detecting, correcting, reducing or removing noise
• CPC Class Codes: H04N 25/61 the noise originating only from the lens unit, e.g. flare, shading, vignetting or "cos4"
• CPC Class Codes: H04N 5/208 for compensating for attenuation of high frequency components, e.g. crispening, aperture distortion correction

Abstract

An electronic camera includes a memory circuit for storing a video signal representing at least a single image, a signal processing circuit for conducting digital processing in a vertical direction with a predetermined characteristic on the video signal read out from the memory circuit in the vertical direction and for conducting digital processing in a horizontal direction with another predetermined characteristic which is different from the predetermined characteristic on the video signal read out from the memory circuit in the horizontal direction, and a control circuit for switching over reading out of the video signal from the memory circuit between the vertical direction and the horizontal direction and for switching over the processing characteristic of the signal processing circuit between the predetermined characteristic and the another predetermined characteristic which is different from the predetermined characteristic.

Claims

1. An electronic camera comprising:

memory means for storing a video signal representative of at least a single image, said memory means allowing read-out operations of the video signal selectively in one of a horizontal direction and a vertical direction;

a filter, having variable frequency characteristics, that can be controlled to have different variable frequency characteristics for data read out from said memory means both in a vertical direction and in a horizontal direction, for filtering an output video signal of said memory means; and

control means for changing the variable frequency characteristics of said filter in accordance with whether the signal is read out from said memory means in a horizontal direction or a vertical direction, so that said filter has first frequency characteristics when the signal is read out in a horizontal direction and said filter has different frequency characteristics when the signal is read out in a vertical direction.

2. The electronic camera according to claim 1, wherein said memory means comprises an X-Y addressing-type memory.

3. The electronic camera according to claim 2, wherein said X-Y addressing-type memory comprises a RAM.

4. The electronic camera according to claim 2, wherein said X-Y addressing-type memory comprises a FIFO memory which allows for write-in and read-out operations of data in both horizontal and vertical directions.

5. The electronic camera according to claim 4, wherein said FIFO memory comprises a plurality of basic cells arranged in columns and rows, each of said basic cells having two data output lines and two data input lines connected thereto.

6. The electronic camera according to claim 1, wherein said filter unit comprises a plurality of series-connected delaying elements, a single adder, and a plurality of coefficient units respectively connected between said individual delaying elements and said adder, a coefficient of each of said coefficient units which is set in the processing in the vertical direction being different from that set in the processing in the horizontal direction.

7. The electronic still camera according to claim 1, wherein said signal processing unit includes a digital signal processing means.

8. The electronic camera according to claim 1, wherein the filtering in the vertical direction in said filter unit includes a digit vertical aperture correction.

9. An electronic camera comprising:

image means for producing a video signal by conducting photoelectric conversion on a light from an object;

memory means for storing the video signal obtained by said imaging means, wherein the video signal is selectively read out from said memory means in one of a plurality of directions;

a filter, having variable frequency characteristics, that can be controlled to have different variable frequency characteristics for data read out from said memory means in each of the plurality of directions, for filtering the video signal read out from said memory means; and

control means for controlling the variable frequency characteristics of said filter in accordance with the direction in which the video signal is read out from said memory means, so that said filter has first frequency characteristics when the signal is read out in one of the plurality of directions and said filter has different frequency characteristics when the signal is read out in another of the plurality of directions.

10. The electronic camera according to claim 9, wherein said memory means comprises an X-Y addressing-type memory which allows for write-in and read-out operations of a signal in both horizontal and vertical directions.

11. The electronic camera according to claim 9, wherein said variable frequency characteristics of said filter unit is changed depending on whether the video signal is read out from said memory means in a horizontal direction or a vertical direction.

12. The electronic camera according to claim 9, wherein said filter unit comprises a plurality of series-connected delaying elements, a single adder, and a plurality of coefficient units respectively connected between said individual delaying elements and said adder, a coefficient of each of said coefficient units which is set in the processing in the vertical direction being different from that set in the processing in the horizontal direction.

13. A signal processing circuit comprising:

signal storage means;

control means for reading out a signal from said signal storage means selectively in one of a plurality of different read-out orders; and

a filter, having a frequency characteristic that is variable, and that can be controlled to have a different variable frequency characteristic in accordance with each of the plurality of different read-out orders, for filtering the signal read out from said signal storage means,

wherein, said filter has first frequency characteristics when the signal is read out in one of the plurality of different read-out orders and said filter has different frequency characteristics when the signal is read out in another of the plurality of different read-out orders.

14. The signal processing circuit according to claim 13, wherein said control means writes the output of said filter unit again in said signal storage means so that a plurality of different signal filtering can be conducted on the signal stored in said signal storage means on a time-sharing basis.

15. The signal processing circuit according to claim 13, wherein said signal storage means comprises an X-Y addressing-type memory.

16. The signal processing circuit according to claim 13, wherein said filter unit comprises a plurality of series-connected delaying elements, a single adder, and a plurality of coefficient units respectively connected between said individual delaying elements and said adder, a coefficient of each of said coefficient units which is set in the processing in the vertical direction being different from that set in the processing in the horizontal direction.

17. The signal processing circuit according to claim 13, wherein said control means comprises a microcomputer.

18. A filter apparatus comprising:

input means for inputting a signal;

a plurality of serially-connected delay units, having output terminals, connected to said input means for serially delaying the signal input by said input means;

a plurality of coefficient units, having respective coefficients, connected to respective ones of said output terminals of said plurality of serially-connected delay units, that can be controlled to have different respective variable coefficients in accordance with a data order that is characteristic of the signal, for multiplying respective output signals of said plurality of delay units by the respective coefficients of said plurality of coefficient units; and

control means for varying the respective coefficients of said plurality of coefficient units in accordance with the data order characteristic of the signal, so that said coefficient units have first coefficients when the signal has a first data order characteristic and said coefficient units have different coefficients when the signal has a second data order characteristic.

19. A filter apparatus according to claim 18, further comprising operation means for performing an operation on the output signals of said plurality of coefficient units.

20. A filter apparatus according to claim 19, wherein said operation means comprises an adding circuit.

21. A filter apparatus according to claim 18, further comprising a signal source for supplying an image signal to said input means.

22. A filter apparatus according to claim 21, wherein said signal source supplies the image signal selectively in one of a plurality of different orders.

23. A filter apparatus according to claim 22, wherein said signal source comprises memory means.

24. A filter apparatus according to claim 22, wherein said signal source supplies the image signal selectively corresponding to a vertical direction and to a horizontal direction.

25. A filter apparatus comprising:

an image signal source for supplying an image signal selectively in one of a plurality of different orders;

a filter, that can be controlled to have a different variable frequency characteristic for data supplied in each of the plurality of different orders, for filtering the image signal; and

control means for controlling the frequency characteristic of said filter in accordance with the order in which the image signal is supplied by said image signal source, so that said filter has a first frequency characteristic when the signal is in a first order and said filter has a different frequency characteristic when the signal is in another order.

26. A filter apparatus according to claim 25, wherein said image signal source comprises memory means.

27. A filter apparatus according to claim 26, wherein said image signal source supplies the image signal selectively in a vertical direction and in a horizontal direction.

28. A filter apparatus according to claim 25, wherein said filter unit comprises a finite impulse response filter.