Image pickup apparatus for producing a desired frame of image signals

• US 7,365,780 B1
• Filed: 09/07/2000
• Issued: 04/29/2008
• Est. Priority Date: 09/14/1999
• Status: Expired due to Fees

• Current Assignee: Fujifilm Corporation (Fujifilm Holdings Corporation)
• Original Assignee: Fujifilm Corporation (Fujifilm Holdings Corporation)
• Inventors: Miyazaki, Takao
• Primary Examiner(s): Ometz; David
• Assistant Examiner(s): NGUYEN, LUONG TRUNG
• Application Number:
  US09/656,995
• Time in Patent Office: 2,791 Days
• Field of Search: 348/231.99, 348/231.6, 348/231.1, 348/231.9, 348/221.1
• US Class Current: 348/231.6
• CPC Class Codes: H04N 23/632 for displaying or modifying preview images prior to image capturing, e.g. variety of image resolutions or capturing parameters
• CPC Class Codes: H04N 23/651 for reducing power consumption by affecting camera operations, e.g. sleep mode, hibernation mode or power off of selective parts of the camera
• CPC Class Codes: H04N 23/70 Circuitry for compensating brightness variation in the scene
• CPC Class Codes: H04N 5/2625 for obtaining an image which is composed of images from a temporal image sequence, e.g. for a stroboscopic effect sequence generated by event triggered capturing H04N7/188

Abstract

An image pickup apparatus capable of outputting one of successive pictures that is picked up at a desired timing. When the operator of the apparatus selects a continuous shoot mode, sets a mode dial at a “Pre (prior)/Post (posterior)” position, and then presses a release button to a half-stroke position, the apparatus picks up a desired scene at preselected intervals. Up to nine latest frames of image data are written to a main memory while being sequentially updated. Subsequently, when the operator presses the release button to a full-stroke position, up to five additional latest frames of image data are written to the main memory. The image data stored in the main memory are read out and transformed to display data. The display data appear on an LCD (Liquid Crystal Display) panel in a multiframe format. When the operator, watching pictures appearing on the LCD panel, selects desired one of the pictures by operating preselected switches arranged on an operation panel, the image data representative of the above picture is recorded in an external memory removably mounted to the apparatus.

Claims

1. An image pickup apparatus, comprising:

an image sensor for picking up a scene in response to a control signal to thereby output an image signal representative of said scene;

a recording device for recording a plurality of frames of image signals;

a selecting device for allowing an operator of said image pickup apparatus to select a desired one of the plurality of frames of image signals recorded in said recording device; and

a controller operative in response to said selecting device for outputting the control signal to cause said image sensor to pick up the scene at preselected intervals and for controlling said recording device,

wherein said controller sets a period of time corresponding to a photometric value as the preselected intervals,

wherein said recording device records latest ones of a plurality of frames of image signals picked up at the preselected intervals while sequentially updating said plurality of latest frames of image signals,

wherein said controller causes said recording device to hold frames of image signals picked up during a period of time based on a release operation, and causes non-selected frames of image signals, as distinguished from the one frame of image signal selected, existing in said recording device to be automatically deleted, such that only the selected one frame of image signal is maintained, wherein to set the period of time corresponding to the photometric value as the preselected intervals, said controller is configured to

determine a shutter time of a shutter based on the photometric value, and

set the period of time to be equal to or longer than a sum of the shutter time and a frame transfer time,

wherein the frame transfer time is a period of time necessary to transfer one frame of pixel signals from said image sensor to said recording device.

2. An apparatus in accordance with claim 1, wherein said controller comprises a mode setting circuit for allowing the operator to set a mode that causes said recording device to hold the frames of image signals picked up during the period of time at least before or after the release operation, whereby the frames of image signals are recorded in said recording device in accordance with said mode.

3. An apparatus in accordance with claim 2, wherein when the operator sets a “

Pre”

mode for causing said recording device to hold the frames of image signals picked up before the release operation, said controller causes said recording device to hold the frames of image signals picked up at least before the release operation.

4. An apparatus in accordance with claim 2, wherein when the operator sets a “

Post”

mode for causing said recording device to hold the frames of image signals picked up after the release operation, said controller causes said recording device to hold the frames of image signals picked up at least after the release operation.

5. An apparatus in accordance with claim 2, wherein when the operator sets a “

Pre/Post”

mode for causing said recording device to hold the frames of image signals picked up before and after the release operation, said controller causes said recording device to hold the frames of image signals picked up before and after the release operation.

6. An apparatus in accordance with claim 1, further comprising a display for displaying pictures represented by the frames of image signals recorded in said recording device, wherein said controller causes a picture represented by the one frame of image signal selected to be distinguished from the other pictures on said display.

7. An apparatus in accordance with claim 6, wherein said controller causes said display to display the pictures together in a preselected format.

8. An apparatus in accordance with claim 2, further comprising a switch circuit for generating first information and second information in response to a first release operation and a second release operation, respectively, wherein said controller controls, in response to said first information, said image sensor and said recording device for executing pickup control at the preselected intervals and recording resulting frames of image signals in said recording device and then causes, in response to said second information and in accordance with the mode set by the operator, said recording device to hold the frames of image signals existing therein.

9. An apparatus in accordance with claim 8, wherein said switch circuit generates the first information when the operator presses a release button to a half-stroke position and then generates the second information when the operator presses said release button to a full-stroke position.

11. An apparatus in accordance with claim 1, further comprising a signal generating circuit for generating timing signals at the preselected intervals under control of said controller, wherein said controller executes the pickup control over said image sensor and storage control over said recording device at said preselected intervals for thereby causing the frames of image signals picked up at said intervals to be written to said recording device.

12. An apparatus in accordance with claim 1, wherein said controller further executes, when executing the pickup control by controlling said image sensor, control for correcting exposure in a plurality of steps, wherein said recording device records latest ones of the plurality of frames of image signals picked up at the preselected intervals and corrected in exposure in said plurality of steps while sequentially updating said latest frames of image signals, and wherein said selecting device allows the operator to select a desired one of image data including image data corrected in exposure in said plurality of steps.

13. An apparatus in accordance with claim 1, further comprising a bilevel image data generating device for generating bilevel image data representative of a bilevel picture to be compared with pictures represented by the plurality of frames of image signals existing in said recording device with respect to a correlation, wherein said controller determines a correlation between each of said pictures and said bilevel picture, and wherein said selecting device allows the operator to select a frame of image data having a high degree of correlation as determined by said controller.

14. An apparatus in accordance with claim 13, wherein said controller transforms each of the frames of signals recorded in said recording device to bilevel image data and compares said bilevel image data and the bilevel image data output from said bilevel image data generating device to thereby determine the correlation.

15. An apparatus in accordance with claim 14, wherein said controller causes the frame of image data having the high degree of correlation to be distinguished from the other frames of image data at the time of display.

16. An apparatus in accordance with claim 13, wherein said controller further executes, when executing the pickup control by controlling said image sensor, control for correcting exposure in a plurality of steps, wherein said recording device records, among the plurality of frames of image signals picked up at the preselected intervals and corrected in exposure in said plurality of steps, a plurality of latest frames of image signals while sequentially updating said plurality of latest frames of image signals, and wherein said selecting device allows the operator to select a desired one of image data including image data corrected in exposure in said plurality of steps.

17. An apparatus in accordance with claim 13, wherein said controller transforms the image data picked up at the preselected intervals without the exposure correction and recorded in said recording device to bilevel image data and compares said bilevel image data and the bilevel image data output from said bilevel image data generating device.

18. An apparatus in accordance with claim 1, wherein said controller is configured to

determine whether the shutter time is faster or equal to the frame transfer time,

set the period of time to be equal to the sum of the shutter time and the frame transfer time when the controller determines that the shutter time is faster or equal to the frame transfer time, and

set the period of time to be equal to a multiple of the shutter time when the controller determines that the shutter time is slower than the frame transfer time,

wherein the multiple is at least 2.

10. An apparatus in accordance with clam 8, wherein said switch circuit comprises a sensor for generating the first information when the operator holds said apparatus in a position ready to shoot the scene.