JP2006121574A - Imaging apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To easily switch photographing and recording modes even during photographing. <P>SOLUTION: The imaging apparatus comprises a control means for switching modes between a first recording mode during which moving image data are encoded and recorded with a target data rate of the moving image data as a first rate, and a second recording mode during which moving image data are encoded and recorded with the target data rate of the moving image data as a second rate different from the first rate; and a display means for displaying a recordable time on a recording medium, wherein the control means changes the first recording mode into the second recording mode in response to the operation of an operating switch during photographing in the first recording mode, and changes a display form of the recordable time on the display means in response to the operation of the operating switch. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an imaging apparatus and more particularly to switching between a plurality of modes.

  2. Description of the Related Art Conventionally, a digital VTR that records and reproduces image signals and audio signals as digital signals on a magnetic tape is known. In recent years, a disk recorder for recording these digital signals on an optical disk such as a DVD has also been proposed (see, for example, Patent Document 1).

In these digital VTRs and disk recorders, in order to effectively use tapes or disks having a limited recording capacity, in addition to the standard recording mode, the recording rate is reduced by increasing the compression rate to reduce the signal data rate. It is also considered to have a time recording mode.
JP 2004-40518 A

  As described above, in a digital VTR or disc recorder having a standard recording mode and a long-time recording mode (or a high image quality mode and a standard mode), a user sets a recording mode in advance before shooting, and shooting (recording). During shooting, shooting is performed in the set recording mode.

  Therefore, for example, in the high image quality mode, a less important scene is recorded with the same amount of data as an important scene, so that the recording medium is wasted.

  In addition, in the standard image quality mode, even if an important scene appears during shooting, it is necessary to temporarily stop shooting and set the recording mode to the high image quality mode. Even if it exists, there exists a problem that this cannot be image | photographed in high image quality mode.

  An object of the present invention is to solve such problems.

  Another object of the present application is to enable easy switching between shooting and recording modes even during shooting.

  In order to solve the above-described problems, the present invention records an image capturing unit, an encoding unit that encodes moving image data obtained by the image capturing unit, and moving image data encoded by the encoding unit. The recording means for recording on the medium, the operation switch, the encoding means for encoding the moving image data with the target data rate of the moving image data as the first rate, and the recording means for encoding the first rate The moving image data is encoded by the encoding means with a first recording mode for recording the converted moving image data and a second data rate different from the first rate as the target data rate of the moving image data. Control means for switching the mode between the second recording mode for recording the moving image data at the second rate by the recording means, and recording on the recording medium. Display means for displaying time, and the control means changes to the second recording mode according to the operation of the operation switch during photographing in the first recording mode, and operates the operation switch. Accordingly, the display mode of the recordable time by the display unit is changed.

  According to the present invention, it is possible to easily switch between shooting and recording modes even during shooting, and shooting and recording operations intended by the user are possible.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In the embodiment described below, a case where the present invention is applied to a disk recorder will be described.

  FIG. 1 is a diagram showing a configuration of a disk recorder 100 to which the present invention is applied.

  In FIG. 1, an image pickup unit 101 includes a known optical system such as a CCD, a lens, and an iris, picks up a subject image, and generates an image signal. Then, the image signal is processed by a built-in camera signal processing circuit, and then output to the encoding unit 103 and the monitor 111. The monitor 111 displays an image corresponding to the image signal obtained by the photographing unit 101 and also displays for menu setting according to a control signal from the control circuit 109. As will be described later, information on the recordable time of the disk 107 is also displayed in a multiplexed manner by OSD display.

  The encoding unit 103 encodes the image signal output from the imaging unit 101 as described later, and outputs the encoded image signal to the recording circuit 105. The recording circuit 105 adds additional data such as synchronization and ID to the image data encoded by the encoding unit 103, and further performs digital modulation processing to convert it into a form suitable for recording, and at a predetermined timing. Recording on the disc 107.

  The operation switch 113 includes various switches such as a power switch 113a, a recording trigger switch 113b, and a mode switch 113c, and outputs an instruction signal corresponding to the operation of each switch to the control circuit 109.

  The control circuit 109 controls the encoding unit 103 and the recording circuit 105 in accordance with the instruction signals from these operation switches 113 and instructs the monitor 111 to display characters for setting various menus. In particular, in this embodiment, there are two shooting modes as will be described later, and the control circuit 109 controls to display a character indicating the current shooting mode on the monitor 111.

  The disc recorder 100 according to the present embodiment includes, as a shooting (recording) mode, a high-quality mode in which the encoding unit 103 generates and records encoded image data of the first bit rate (10 Mbps in this embodiment), A standard image quality mode in which encoded image data of a bit rate (5 Mbps in this embodiment) is generated and recorded, and these shooting modes can be arbitrarily set by the operation switch 113.

  Next, the encoding unit 103 will be described. The encoding unit 103 encodes the input image signal by motion compensated prediction encoding according to MPEG2.

  FIG. 2 is a diagram illustrating a configuration of the encoding unit 103.

  In the figure, an image signal obtained from the imaging unit 101 is input to a screen rearrangement circuit 201. The screen rearrangement circuit 201 has a memory capable of storing image signals for a plurality of frames (four frames in this embodiment), and rearranges the order of the input image signals in units of frames, The result is output to the motion compensation prediction circuit 221.

  FIG. 3 is a diagram illustrating the order of image signals input to and output from the rearrangement circuit 201.

  As shown in FIG. 3A, the screen rearrangement circuit 201 converts the image signals input in the order of frames 1, 2, 3,... Into frames 3, 1, 2, 6, 4, 5 as shown in FIG. Output in the order of….

  FIG. 4 is a diagram showing the order of encoded frames by the encoding unit 103 of this embodiment.

  The encoding unit 103 of this embodiment uses two types of encoding, intra encoding and inter encoding.

  Intra coding is coding using only image data in one frame, and inter coding is coding using a plurality of frames such as inter-frame predictive coding.

  In MPEG2, encoding is performed by distinguishing each frame from an I picture, a P picture, and a B picture depending on the type of encoding.

  An I picture is a frame that intra-codes all image data, a P picture is a frame that performs forward predictive coding using image data of the forward I picture or P picture, and a B picture is the preceding or following I or P picture A frame from which I picture data is subjected to bidirectional predictive coding, and a picture from an I picture to a picture immediately before the next I picture is called a GOP (Group Of Pictures). Normally, 1 GOP is composed of 15 frames of image signals.

  FIG. 4 is a diagram showing the order in which the encoding unit 103 generates and encodes these I picture, P picture, and B picture.

  In the figure, image signals rearranged in the order of frame 3, frame 1, frame 2, frame 6... Are input from the screen rearrangement circuit 201. First, since frame 3 is an I picture, only the image data of frame 3 is input. Is intra-coded. Next, since frame 1 is a B picture, it is encoded with the image data of frame 3 that is the immediately preceding P picture (not shown in the previous GOP) and the immediately following I picture. Similarly, frame 2 is encoded with the image data of frame 3, which is the immediately preceding P picture (not shown) and the immediately following I picture. Next, frame 6 is input. Since frame 6 is a P picture, forward prediction encoding is performed using the image data of frame 3 which is the immediately preceding I picture.

  Thereafter, the image data of each frame is similarly encoded.

  Returning to FIG. 2, the description of the encoding unit 103 will be continued.

  The image data output from the screen rearrangement circuit 201 is output to the subtracter 203, and the subtracter 203 obtains a difference from the predicted image data output from the motion compensation prediction circuit 221 and outputs the difference to the switch 205.

  The switch 205 is controlled by the switch control circuit 225. When the image data input from the screen rearrangement circuit 201 is an I picture, the switch 205 is connected to the A side and the image data output from the screen rearrangement circuit 201 is converted to a DCT circuit. In the case of a B picture or a P picture, the difference data output from the subtracter 203 is selected and output to the DCT circuit 207.

  The DCT circuit 207 performs DCT processing on the image data output from the switch 205 and outputs it to the quantization circuit 209. The quantization circuit 209 quantizes the output data from the DCT circuit 207 using the quantization coefficient selected according to the instruction from the rate conversion circuit 225 and outputs the quantized data to the variable length coding circuit 211 and the inverse quantization circuit 215.

  The variable length encoding circuit 211 encodes the output data from the quantization circuit 209 using a variable length code such as a Huffman code and outputs the encoded data to the buffer memory 213. The buffer memory 213 can store encoded image data of a predetermined number of frames, and outputs the stored encoded image data to the recording circuit 105 at a predetermined timing.

  The rate control circuit 225 checks the amount of image data stored in the buffer memory 213, and the quantization circuit 209 performs quantization so that the data rate of the encoded image data output from the buffer memory 213 becomes substantially the target rate. Set the coefficient. Further, the rate control circuit 225 changes the target rate between the high image quality mode and the standard image quality mode in accordance with a control signal from the control circuit 109, as will be described later.

  The inverse quantization circuit 215 inversely quantizes the data quantized by the quantization circuit 209 and outputs the result to the inverse DCT circuit 217. The inverse DCT circuit 217 performs inverse DCT processing on the image data inversely quantized by the inverse quantization circuit 215 and outputs the processed image data to the adder 219. The adder 219 adds the output image data from the inverse DCT circuit 217 and the image data from the switch 223 and outputs the result to the motion compensation prediction circuit 221.

  The motion compensation prediction circuit 221 has a memory capable of storing the image data output from the adder 219 for a plurality of frames. When the image data to be encoded is a B or P picture, the image data stored in these memories is stored. Of these, the predicted image data is determined using the image data of the reference frame and the image data output from the screen rearrangement circuit 201. Then, the predicted image data is read from the internal memory and output to the subtracter 203 and the switch 223.

  The switch 223 is controlled by the switch control circuit 227 and is connected only when the image output from the screen rearrangement circuit 201 is a B or P picture, and outputs the prediction data from the motion compensation prediction circuit 221 to the adder 219.

  Next, the recording circuit 105 will be described.

  FIG. 5 is a diagram showing the configuration of the recording circuit 105.

  In the figure, the image data encoded by the encoding unit 103 is output to the format circuit 501. The format circuit 501 adds the synchronization, ID data, and other additional data generated by the additional information generation circuit (not shown) to the input image data, and writes it to the buffer memory 503. The buffer memory 503 can store a predetermined amount of recording data, and the recording data stored in the buffer memory 503 is read out by the modulation circuit.

  The modulation circuit 505 reads the recording data stored in the buffer memory 505 in accordance with the recording timing by the recording circuit 507, performs digital modulation processing, and outputs it to the recording circuit 507. A recording circuit 507 records digital data on the disk 107 in accordance with the output of the modulation circuit 505.

  The servo circuit 509 controls the mechanism 511 in accordance with a control signal from the control circuit 109 to rotate the disk 107, and controls the disk 107 to rotate at a constant rotational speed in accordance with a timing signal from the mechanism 511. To do. The servo circuit 509 outputs a timing signal accompanying the rotation of the disk 107 to the modulation circuit 505.

  In this embodiment, since the data rate that can be recorded by the recording circuit 507 is several times higher than the data rate of the encoded image data, the recording circuit 507 performs recording once per n rotations of the disk 107. Therefore, the modulation circuit 505 reads image data from the buffer memory 503 at a predetermined timing so that the recording circuit 507 performs recording once in n rotations in accordance with the timing signal from the servo circuit 509.

  Further, the modulation circuit 505 changes the read timing from the buffer memory 503 in accordance with the shooting mode by a control signal from the control circuit 109.

  Next, an operation related to switching of shooting modes in this embodiment will be described.

  As described above, the disk recorder of this embodiment includes the high image quality mode and the standard image quality mode. When the user does not shoot (record), the operation switch 113 displays a menu on the monitor 111 and uses this menu display to set the shooting mode.

  The control circuit 109 outputs a control signal to the encoding unit 103 and the recording circuit 105 in accordance with the shooting mode set as described above.

  Specifically, a control signal is output to the rate control circuit 225 in FIG. In accordance with this control signal, the rate control circuit 225 controls the quantization coefficient used in the quantization circuit 209 so that the data rate of the image data output from the buffer memory 213 is close to 10 Mbps in the high image quality mode. In the mode, the quantization coefficient used in the quantization circuit 209 is controlled so that the data rate of the image data output from the buffer memory 213 is close to 5 Mbps.

  Further, a control signal is output to the modulation circuit 505 for the recording circuit 105. In accordance with this control signal, the modulation circuit 505 reads data from the buffer memory 503 so as to record data once in n rotations of the disk 107 in the high image quality mode, and once in 3n rotations of the disk 107 in the standard image quality mode. Data is read from the buffer memory 503 so as to perform recording.

  Further, the present embodiment is configured such that the shooting mode can be switched even during shooting in such a preset shooting mode.

  That is, by operating the operation switch 113c during shooting, it is possible to switch to a mode different from the normally set shooting mode during the operation period.

  Specifically, for example, by operating the operation switch 113c during shooting in the standard image quality mode, the apparatus mode is set to the high image quality mode during this operation period.

  For example, when receiving an instruction from the mode switch 113c during shooting in the standard image quality mode, the control circuit 109 switches the apparatus mode to the high image quality mode during the period in which the instruction signal is output in response to the instruction signal. When the operation of the mode switch 113c is canceled, the standard image quality mode is set again. FIG. 6 shows how the data rate of the image data encoded by the encoding unit 103 changes at this time.

  In FIG. 6, when the mode switch 113c is operated, a control signal is output to the encoding unit 103. The encoding unit 103 gradually increases the data rate in accordance with the control signal and sets the target data rate to 10 Mbps. And After that, when the operation of the mode switch 113c is released, the encoding unit 103 increases the data rate this time and sets the target data rate to 5 Mbps.

  At this time, the control circuit 109 switches the display form of the recordable time of the disk 107 to the monitor 111 as shown in FIG.

  Thus, in this embodiment, when the mode switch 113c is operated during shooting, the shooting mode can be switched even during shooting.

  Therefore, even if it is desired to switch modes during shooting, there is no need to interrupt the shooting operation and reset the shooting mode.

  Therefore, for example, during shooting in the high image quality mode, a scene that the user determines is not very important can be recorded in the standard image quality mode only by operating the mode switch 113c, and a large amount of recording capacity is consumed for an unimportant scene. Can be prevented.

  Further, usually, shooting in the normal image quality mode saves the disk consumption capacity, and shooting in the high image quality mode can be performed by operating the mode switch 113c in a scene that the user likes. Note that the images displayed on the monitor 111 are the same in the high image quality mode and the standard image quality mode, but the character indicating the current shooting mode is always displayed on the monitor 111. The user can easily confirm in which shooting mode the user is currently shooting.

  In the above-described embodiment, the mode is set to be switched only during the operation period of the mode switch 113c. However, this may be configured by a trigger switch so that the mode is switched for each operation.

  Alternatively, the mode may be switched only for a predetermined period by operating the mode switch 113c once, and automatically switched to the original photographing mode after the predetermined period.

  In the above-described embodiment, an apparatus having two recording modes has been described. However, three or more shooting modes may be provided, and the plurality of shooting modes may be arbitrarily changed by operating a switch during shooting. .

  In the above-described embodiment, motion compensation predictive coding is used, but other than this, coding including other high-efficiency coding processing, information amount compression processing, and signal processing may be used.

  In the above-described embodiment, the case where the present invention is applied to a disk recorder has been described. However, other than this, for example, data is recorded via a semiconductor memory, a device for recording data on a hard disk, or a network. Similarly, the present invention can be applied to a system that transmits and records in a server or the like, and has the same effect.

1 is a diagram illustrating a configuration of a recording apparatus to which the present invention is applied. It is a figure which shows the structure of an encoding part. It is a figure which shows the rearrangement process of the screen by an encoding part. It is a figure which shows the mode of an encoding process. It is a figure which shows the structure of a recording circuit. It is a figure which shows the change of the data rate accompanying the change of a recording mode. It is a figure which shows the display form of recordable time.

Claims (1)

Imaging means;
Encoding means for encoding moving image data obtained by the imaging means;
Recording means for recording the moving image data encoded by the encoding means on a recording medium;
An operation switch;
First encoding the moving image data by the encoding means using the target data rate of the moving image data as a first rate, and recording the encoded moving image data at the first rate by the recording means. The moving image data is encoded by the encoding unit with the recording mode and the target data rate of the moving image data being a second rate different from the first rate, and the moving image having the second rate is encoded by the recording unit. Control means for switching a mode between a second recording mode for recording image data;
Display means for displaying the recordable time in the recording medium,
The control means changes to the second recording mode in accordance with the operation of the operation switch during shooting in the first recording mode, and sets the recordable time by the display means in accordance with the operation of the operation switch. An imaging apparatus characterized by changing a display form.

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