JPH0937127A - Image pickup device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent a distorted image during the period of a change from an animation mode to a still picture mode from being recorded. SOLUTION: The output video signal of an image pickup circuit 101 is encoded, written later in memories 108-110 by a write control circuit 107 and a read control circuit 111 and recorded in a recorder 113 while reading is controlled. Besides, during the period of transition from the state of picking up the animation to the mode for picking up a still picture at the point of change from the animation recording mode to the still picture recording mode (the control period of an iris and a CCD output signal amplifier circuit corresponding to the change of shutter speed), the interval of write and read of the memories 108-110 is controlled corresponding to this period of state transition to the animation mode and control is performed so as to recover the interval at the time of the animation mode while a still picture frame is continuously recorded plural times.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image pickup apparatus such as a video camera for picking up and recording moving images and still images.

[0002]

2. Description of the Related Art In an image pickup apparatus capable of recording a moving image and a still image, a method of repeatedly recording a still image frame is considered in consideration of searchability of a still image recording area at the time of search and errors in the still image recording area. Proposed. FIG. 4 is a block diagram showing a conventional image pickup apparatus. In FIG. 4, reference numeral 301 denotes an image pickup circuit which includes a lens, an optical filter, an iris, a CCD, and a CCD drive driver, and which photoelectrically converts a subject image to output an image pickup signal, and 302 denotes a digital video signal obtained by A / D converting the image pickup signal. A / D conversion circuit for outputting
It is a digital encoding circuit including a blocking circuit 304, an orthogonal transformation circuit 305, a quantization circuit 306, and a memory circuit 311. The blocking circuit 304 has a built-in 2-frame block memory and shuffles and blocks digital image data to output blocked data. This blocked data is input to the orthogonal transform circuit 305, and orthogonal transform coefficient data is output. The orthogonal transform coefficient data is input to the quantization circuit 306, quantized in accordance with the orthogonal transform coefficient, and the quantized data is output. The quantized data is input to the memory circuit 311.

The memory circuit 311 has a memory (0) 308 and a memory (1) 309 each having a capacity of 1 frame (hereinafter, each memory will be referred to as a bank).
And a switch 307 for switching banks at the time of writing to the memory and a switch 310 controlled to select a bank different from the bank at the time of reading, where the data is deshuffled and the recording apparatus It is input to 312. Further, the mode changeover switch 314 selects the moving image recording mode or the still image recording mode (including the shutter speed), and the control circuit 3
13 controls switches 307 and 310 in the imaging circuit 301 and the memory circuit 311.

When the moving image mode is selected by the mode selector switch 314, the blocking circuit 304 is used.
The block memory in the inside, the frame memory in the memory circuit 311 (memory (0) 308, memory (1) 309)
Two frames of memory are alternately used as write and read banks. Further, when the still image mode is set by the mode changeover switch 314, it is possible to change the shutter speed to an arbitrary value in the image pickup circuit 301, and the iris is changed so as to obtain an appropriate exposure according to the shutter speed. (At shutter speed priority AE). The quantized data captured as a still image is written to the memory in a state where the writing bank is fixed by the switch 307 in the memory circuit 311, and the reading of the memory is fixed to the bank opposite to the writing by the switch 310. Still image data is output by continuously reading data in the same bank for a plurality of frame periods. A recording device 312 records a moving image and a still image.

FIG. 5 is a frame-by-frame timing chart for explaining the conventional method, and 401 shows the timing for changing the iris in the still picture mode. Reference numeral 402 denotes a frame number of data input to the blocking circuit 304 (where N is the frame number of data in the period in which the iris is changing). Reference numeral 403 indicates a frame number of data output from the blocking circuit 304 and input to the memory circuit 311, and 404 indicates a frame number of data read from the memory circuit 311 and recorded on a recording medium. Reference numeral 405 indicates the timing of the control signal of the write control switch 307 in the memory circuit 311.
Reference numeral 406 indicates the timing of the control signal of the read control switch 310.

Here, the still image mode (including the shutter speed) is selected before the time T (sec), and the iris control according to the set shutter speed is performed during the period from the time T to T + 1/30 (sec). If the frame number of the data taken in during the iris control is N, the image of the frame number N + 1 is recorded as a still image in a plurality of frames. 1 by the block memory in the blocking circuit 304
The frame-delayed data is input to the memory circuit 311 and is written at the write control switch 3 at a timing 405.
07 is controlled, and in the moving image mode up to T + 2/30 (sec), the data is alternately written in the memory (0) 308 and the memory (1) 309 in a frame unit, and T + 2/30 (s)
During the period of the still image recording mode from ec) to T + 7/30 (sec), the writing bank is fixed, and then the operation returns to the moving image mode.

The memory circuit 311 is read by controlling the read control switch 310 at the timing indicated by 406 so that the bank opposite to the write bank is selected. The frame recorded by the recording device 312 is the frame number N, as indicated by 404.
After this, 5 frames of image data of frame number N + 1 are recorded, and the process returns to the moving image mode at frame number N + 6.

[0008]

As described above, according to the conventional method, when a still image is to be recorded during moving image recording, a still image with a changed shutter speed is stabilized from the state in which a moving image is being captured. In order to pick up an image, it takes time to readjust the iris and adjust the gain of the CCD output signal amplifier circuit. For this reason, the transitional state (iris, iris,
An image of N frames during the gain adjustment of the CCD output signal amplification circuit) will be recorded, and an inappropriate image will be recorded as a moving image. Therefore, a video image that is disturbed before the still image is reproduced during reproduction. There was a problem of being played.

The present invention has been made to solve the above problems, and provides an image pickup apparatus capable of eliminating the recording of unstable images during the transition from the moving image mode to the still image mode. With the goal.

[0010]

According to the present invention, an image pickup means for picking up a subject image and outputting a video signal, a storage means for storing a video signal obtained from the image pickup means, and a moving image are picked up. Setting means for selectively setting the first mode and the second mode for capturing a still image; and writing and reading of the storage means according to the mode setting of the setting means. In the first mode, the video signal is continuously read, in the second mode, the same video portion of the video signal is repeatedly read a plurality of times, and the video portion in the transition period from the first mode to the second mode. Is provided with control means for controlling so as not to read.

[0011]

According to the present invention, the control means controls the writing and reading of the storage means according to the first and second modes, so that the video signal is continuously output in the first mode, and the moving image is displayed. In the second mode, the same video portion such as the same frame of the video signal is repeatedly output a plurality of times to obtain a still image. In addition, the distorted image portion during the transition period from the first mode to the second mode is not read.

[0012]

1 is a block diagram showing an embodiment of the present invention. In FIG. 1, 101 is an image pickup circuit that includes a lens, an optical filter, an iris, a CCD, and a CCD drive driver, and photoelectrically converts a subject image to output an image pickup signal, and 102 is a digital video signal obtained by A / D converting the image pickup signal. An A / D converter circuit 103 for outputting a block circuit 104, an orthogonal transform circuit 105, a quantization circuit 106,
A digital encoding circuit including a memory circuit 112, 113
Is a recording device for writing encoded data to a recording medium.

FIG. 2 is a block diagram showing an example of the configuration of the image pickup circuit 101, in which 501 is a lens, 502 is an iris, and 5 is an iris.
03 is an optical filter, 504 is a CC as an image sensor
D, 505 is an amplifier circuit for amplifying the output signal of the CCD 504, 506 is an iris drive circuit for driving the iris 502, 507 is a CCD drive circuit for driving the CCD 504,
Reference numeral 508 is a gain adjustment circuit that adjusts the output of the amplification circuit 505, 509 is an exposure detection circuit that detects exposure from the output of the amplification circuit 505, and 510 is a CCD drive signal that controls the CCD drive circuit 507, and controls the gain adjustment circuit 508. The shutter speed control circuit outputs a gain adjustment signal and an iris control signal for controlling the exposure detection circuit 509 as a still image mode signal.

Next, the operation will be described. In FIG. 2, a subject image passes through a lens 501 and an iris 502, further passes through an optical filter 503 which is an optical LPF for suppressing high frequency components of the subject and suppresses false color signals, and is focused on a CCD 504 to form an electrical signal. And the electric signal is amplified by the amplifier circuit 505. When the image is captured in the moving image mode, the CCD drive circuit 507 is normally 1/6
The iris drive circuit 506 is controlled when the exposure detection circuit 509 determines that the output of the amplification circuit 505 does not indicate proper exposure because the drive is performed for 0 seconds.

Next, when the mode shifts to the still image mode, if the shutter speed is faster than 1/60 seconds and the image is taken, a stable still image cannot be taken if the image is taken in the same state as the moving image mode. Therefore, when the still image mode signal is input to the shutter speed control circuit 510 and an arbitrary shutter speed is designated, the CCD control signal, the gain adjustment signal, and the iris control signal corresponding to the shutter speed are calculated in advance and the appropriate values are calculated. The iris 502 and the amplification circuit 505 are controlled so as to be exposed. The output of the amplifier circuit 505 is A in FIG.
It is sent to the encoding circuit 103 via the / D conversion circuit 102.

Blocking circuit 10 in encoding circuit 103
Reference numeral 4 contains a 2-frame block memory, which shuffles and blocks input digital image data and outputs block data. This blocked data is input to the orthogonal transform circuit 105, and orthogonal transform coefficient data is output. The orthogonal transform coefficient data is input to the quantization circuit 106, quantized according to the orthogonal transform coefficient, and quantized data is output, and the quantized data is input to the memory circuit 112. The memory circuit 112 has a memory (0) 108, a memory (1) 109, a memory (2) 110 (each memory will be referred to as a bank hereinafter) having a capacity of 1 frame, and writing to each memory. It is composed of a write control circuit 107 that sometimes controls a bank and a read control circuit 111 that controls so as to select a bank different from the write bank when reading. The input quantized data is deshuffled by the memory circuit 112 and input to the recording device 113.

The mode changeover switch 115 selects a moving image recording mode or a still image recording mode (including shutter speed), and the control circuit 114
The image pickup circuit 101, the write control circuit 107 and the read control circuit 111 in the memory circuit 112 are controlled.

When the moving image mode is selected by the mode selector switch 115, the block memory in the blocking circuit 104 alternately uses the memory for two frames as the write and read banks. Further, the frame memory in the memory circuit 112 (memory (0) 108, memory (1) 109, memory (2) 1
10) is configured to have another bank in addition to writing and reading, and the written data is controlled and read so as to be read after two frames. The memory of another bank is used for image processing in the still image mode and processing such as ECC and digital interface at the time of playback in the case of the recording / playback shared circuit, and the delay amount is adjusted in the processing in the video recording mode. Will be used for.

Further, when the still image mode is set by the mode changeover switch 115, it is possible to change the shutter speed in the image pickup circuit 101 to an arbitrary shutter speed, and the iris is adjusted so as to obtain an appropriate exposure according to the shutter speed. Is changed (during shutter speed priority AE). The quantized data captured as a still image is stored in the memory circuit 112.
The write control circuit 107 therein writes the data in the memory with the write bank fixed. The reading of the memory is fixed to the bank different from the writing by the reading control circuit 111, and the still image data is output by reading the data of the same bank continuously for a plurality of frame periods and is recorded by the recording device 113.

FIG. 3 is a frame-by-frame timing chart for explaining the present embodiment, and 201 shows the timing for changing the iris in the still picture mode. Reference numeral 202 denotes a frame number of data input to the blocking circuit 104 (the frame number of data in the period in which the iris is changing is N). Reference numeral 203 denotes a frame number of data output from the blocking circuit 104 and input to the memory circuit 112, and 204 denotes a frame number of data read from the memory circuit 112 and recorded by the recording circuit 113. Reference numeral 205 shows the timing of the control signal of the write control circuit 107 in the memory circuit 112. Two
06 indicates the timing of the control signal of the read control circuit 111. The numbers 0 to 2 of 205 and 206 are memory (0) 108, memory (1) 109, and memory (2) 11
It is connected to 0.

Here, the still image mode (including the shutter speed) is selected before the time T (sec), and the iris control according to the shutter speed set in the period of T + 1/30 (sec) from the time T is performed. If the frame number of the data taken in during the iris control is N, the image of frame number N + 1 is recorded as a still image in a plurality of frames. 1 by the block memory in the blocking circuit 104
The frame-delayed data is input to the memory circuit 112, and at the timing indicated by 205, the write control circuit 107
Is controlled, and in the moving image mode up to T + 2/30 (sec), the memory (0) 108, the memory (1) 109, and the memory (2) 110 are sequentially selected and written for each frame, and T + 2/30 (sec). ) To T + 6/3
During the still image recording mode of 0 (sec), the writing bank is fixed, and then the operation returns to the moving image mode.

The reading of the memory circuit 112 is controlled by the read control circuit 111 at a timing 206.
In movie mode, if the writing bank is M (M
+1) It is controlled to select the read bank in the relation of mod3, and when fixing the bank in the still image mode,
The read bank is controlled so as to be (M + 2) mod3. As a result, the frames recorded by the recording device 312 are thinned out after the frame number N-1 and the image data of the frame number N are recorded, and still image data of the frame number N + 1 are continuously recorded for 5 frames, as shown by 204. The frame number N + 5 is returned to the moving image mode. That is, the image data of the frame number N, which is an unstable image, is not recorded.

[0023]

As described above, according to the present invention, when an attempt is made to record a still image during moving image recording, a still image with a changed shutter speed can be stably obtained from the state where a moving image is being captured. Since a frame image is not recorded in an excessive state of state transition time due to readjustment of iris for image pickup, gain adjustment of CCD output signal amplifier circuit, etc. A stable image can be played back without disturbing an image.

[Brief description of drawings]

FIG. 1 is a block diagram showing an embodiment of the present invention.

FIG. 2 is a block diagram illustrating a configuration example of an image pickup circuit in FIG.

FIG. 3 is a timing chart showing the operation of the embodiment.

FIG. 4 is a block diagram showing a conventional imaging device.

FIG. 5 is a timing chart showing a conventional operation.

[Explanation of symbols]

 101 image pickup circuit 112 memory circuit 107 write control circuit 108 memory (0) 109 memory (1) 110 memory (2) 111 read control circuit 112 memory circuit 113 recording device 114 control circuit 115 mode changeover switch 502 iris 504 CCD 505 amplification circuit 506 Iris drive circuit 507 CCD drive circuit 508 Gain adjustment circuit 509 Exposure detection circuit 510 Shutter speed control circuit

Claims (4)

[Claims] 1. An image pickup means for picking up a subject image and outputting a video signal, a storage means for storing a video signal obtained from the image pickup means, a first mode for picking up a moving image, and a still image pickup. And a setting means for selectively setting a second mode for carrying out the operation, and writing and reading of the storage means according to the mode setting of the setting means. In the first mode, the video signal is set. Is continuously read, the same video portion of the video signal is repeatedly read a plurality of times in the second mode, and control is performed so as not to read the video portion in the transition period from the first mode to the second mode. And an image pickup apparatus including. 2. The image pickup device comprises an image pickup device for photoelectrically converting the subject image, a shutter control device for controlling an electronic shutter speed, and a gain control device for a video signal output from the image pickup device. 1. The imaging device according to 1. 3. The image pickup apparatus according to claim 1, wherein the storage means has a storage capacity for three frames. 4. The control means writes and reads the first image portion while repeatedly reading the same image portion from the storage means a plurality of times after a transition period from the first mode to the second mode. The image pickup apparatus according to claim 1, wherein the timing is returned to the mode.