JP4208342B2 - Image recording apparatus, method, and computer-readable storage medium - Google Patents

Description

としている。
【００２５】
上記のようにレートを制御すると、始めは画質優先で記録をしながらも、記録媒体の残量が減少し、記録レートの上限が定められることによって、最低限あと何分記録可能かをユーザが知ることができる。また、さらに残量が少なくなり、記録レートが固定になることによって、ユーザは残りの記録可能時間を正確に知ることができる。この時も、レート制御部は残りの記録可能時間の情報を表示部１２０に表示する。
【００２６】
次に本発明の他の実施の形態としての記憶媒体について説明する。
本発明は、ハードウェア構成により実現することもできるが、ＣＰＵとメモリからなるコンピュータシステム構成により実現することもできる。コンピュータシステムに構成する場合、上記メモリは本発明によるコンピュータ読み取り可能な記憶媒体を構成する。
【００２７】
即ち、上記実施の形態で説明した動作を実行するためのソフトウェアのプログラムコードを記憶した記憶媒体をシステムや装置で用い、そのシステムや装置のＣＰＵが上記記憶媒体に格納されたプログラムコードを読み出し、実行することにより、本発明の目的を達成することができる。
【００２８】
また、この記憶媒体としては、ＲＯＭ、ＲＡＭ等の半導体メモリ、光ディスク、光磁気ディスク、磁気媒体等を用いてよく、これらをＣＤ−ＲＯＭ、フロッピィディスク、磁気テープ、磁気カード、不揮発性メモリカード等に構成して用いてよい。
【００２９】
従って、この記憶媒体を図１に示したシステムや装置以外の他のシステムや装置で用い、そのシステムあるいはコンピュータがこの記憶媒体に格納されたプログラムコードを読み出し、実行することによっても、上記実施の形態と同等の機能を実現できると共に、同等の効果を得ることができ、本発明の目的を達成することができる。
【００３０】
また、コンピュータ上で稼働しているＯＳ等が処理の一部又は全部を行う場合、あるいは記憶媒体から読み出されたプログラムコードが、コンピュータに挿入された拡張機能ボードやコンピュータに接続された拡張機能ユニットに備わるメモリに書き込まれた後、そのプログラムコードの指示に基づいて、上記拡張機能ボードや拡張機能ユニットに備わるＣＰＵ等が処理の一部又は全部を行う場合にも、上記実施の形態と同等の機能を実現できると共に、同等の効果を得ることができ、本発明の目的を達成することができる。
【００３１】
【発明の効果】
以上説明したように、本発明によれば、画質を優先して記録しながらも、記録媒体の残量によっては、記録可能時間を正確に計算することが可能となる。特に、記録媒体の残量が少なくなった場合に、記録レートを一定にして記録することにより、ユーザが残りの記録可能時間を正確に把握することができ、より有効に記録媒体を利用することができる。
【図面の簡単な説明】
【図１】本発明の実施の形態によるカメラ一体型画像記録装置を示すブロック図である。
【図２】画面入れ替えを説明するための構成図である。
【図３】符号化順序を示す構成図である。
【図４】レート制御を説明するための特性図である。
【図５】記録媒体の使用率に応じたレート制御を説明するための特性図である。
【符号の説明】
１０３ カメラ信号処理部
１０５ スイッチ
１０６ 減算器
１０７ ＤＣＴ部
１０８ 量子化部
１０９ 可変長符号化部
１１０ 逆量子化部
１１１ ＩＤＣＴ部
１１２ 加算器
１１３ 動き補償予測部
１１４ スイッチ
１１５ バッファ
１１６ レート制御部
１１７ 記録媒体[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an image recording apparatus and method suitable for recording digital moving images, and a computer-readable storage medium used therefor.
[0002]
[Prior art]
In a conventional image recording apparatus for recording a digital moving image, a method of prioritizing a target recording time by recording on a recording medium at a constant recording rate by using inter-frame coding of a moving image, and recording at a variable rate There is a method of keeping the image quality constant by doing so.
[0003]
[Problems to be solved by the invention]
In the above conventional technique, when the target recording time to be recorded on the recording medium is prioritized and the recording rate is constant, quantization is performed when the input image moves fast or the color band is wide. There is a problem that the image becomes rough and the image is not uniform for each frame.
In addition, when the image quality is prioritized and the quantization table is fixed, there is a problem in that the recording time cannot be accurately calculated because the recording rate is not constant.
[0004]
The present invention has been made to solve the above-described problem, and an object of the present invention is to be able to calculate the recordable time according to the remaining amount of the recording medium while giving priority to the image quality.
[0005]
[Means for Solving the Problems]
Therefore, in order to solve such a problem, the present invention provides an encoding unit that encodes an input moving image signal, and a recording that records the encoded moving image data obtained by the encoding unit on a recording medium. Means for detecting the remaining capacity of the recording medium, and when the remaining capacity of the recording medium is greater than a predetermined amount, the recording mode of the encoded moving image data specifies the encoding mode of the encoding means When the first encoding mode that does not exceed the upper limit of the recording medium is set and the remaining capacity of the recording medium is smaller than a predetermined amount, the encoding mode of the encoding means is set to a recording rate of the encoded moving image data. Control means for setting the second encoding mode and calculating a time of a moving image recordable on the recording medium from the set encoding mode and the remaining capacity of the recording medium and displaying the time on the display device ; Provided And wherein the door.
[0006]
The present invention also relates to an image recording method in an image recording apparatus for recording encoded moving image data obtained by encoding an input moving image signal on a recording medium, and detecting a remaining capacity of the recording medium. And when the remaining capacity of the recording medium is greater than a predetermined amount, the encoding mode is set to a first encoding mode in which the recording rate of the encoded moving image data does not exceed a specific upper limit, and the recording When the remaining capacity of the medium is smaller than a predetermined amount, the encoding mode is set to a second encoding mode in which the recording rate of the encoded moving image data is constant, and the set encoding mode and the recording medium characterized by chromatic control step of displaying from the remaining capacity calculated display time of a moving picture that can be recorded on the recording medium.
[0007]
In addition, the present invention provides a computer , an encoding unit that encodes an input moving image signal, a recording unit that records encoded moving image data obtained by the encoding unit on a recording medium, and the recording medium Detecting means for detecting the remaining capacity of the recording medium, and when the remaining capacity of the recording medium is larger than a predetermined amount, the encoding mode of the encoding means is set so that the recording rate of the encoded moving image data does not exceed a specific upper limit. When the encoding mode is set to 1 and the remaining capacity of the recording medium is smaller than a predetermined amount, the encoding mode of the encoding unit is set to a second encoding mode in which the recording rate of the encoded moving image data is constant. Pro for and sets, to the control means for displaying the calculated display time of a moving picture that can be recorded on the recording medium and a remaining capacity of the set coding mode and the recording medium, thereby to function Characterized by a computer-readable remembers medium storing a ram.
[0008]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described below with reference to the drawings.
FIG. 1 is a block diagram showing a camera-integrated image recording apparatus according to an embodiment of the present invention.
In FIG. 1, 101 is a lens, 102 is an image sensor such as a CCD, 103 is a camera signal processing unit, 104 is a screen rearranging unit, 105 is a switch, 106 is a subtractor, 107 is a DCT unit, 108 is a quantization unit, 109 is a variable encoding unit, 110 is an inverse quantization unit, 111 is an IDCT unit, 112 is an adder, 113 is a motion compensation prediction unit, 114 is a switch, 115 is a buffer, 116 is a rate control unit, 117 is a recording circuit, Reference numeral 118 denotes a magneto-optical disk as a recording medium. Reference numeral 119 denotes an operation unit that issues a recording instruction and an encoding mode instruction.
[0009]
Next, the operation will be described.
An image input from the lens 101 is input to the camera signal processing unit 103 as a digital image signal for each frame by the image sensor 102. In the camera signal processing unit 103, a correction value is determined using the image signal, and the image data obtained by correcting the image signal is divided into a color difference signal and a luminance signal and input to the screen rearrangement unit 104 and the display unit 120 in units of one frame. To do. The screen rearrangement circuit 104 has a memory that can store a plurality of frames by changing the order of the input frames, and outputs the output by changing the order of the input frames.
[0010]
The screen rearrangement will be described with reference to FIG.
FIG. 2 shows an example of the order in which the screen rearrangement unit 104 rearranges.
The screen rearrangement unit 104 receives the first frame, the second frame, the third frame, and so on, and outputs the second frame, the third frame, the first frame, and so on.
Such screen rearrangement is necessary for performing intra coding and inter coding as shown in FIG.
[0011]
Intra coding is coding using only data in a frame, and is coding for generating the I picture of FIG. In addition, inter coding is coding including inter-frame prediction, and is coding for generating the P and B pictures in FIG.
[0012]
Next, intra coding and inter coding will be described.
In FIG. 1, when performing intra coding, the switch 105 is connected to the A side and the switch 114 is turned off. The image data output from the screen rearrangement unit 104 is input to the DCT unit 107 via the switch 105 and orthogonally transformed. The orthogonally transformed image data is quantized by the quantizing unit 108 according to the quantization coefficient determined by the rate control unit 116 according to the remaining amount of the recording medium 117. The quantized image data is input to the inverse quantization unit 110 and the variable length coding unit 109.
The image data output from the screen rearrangement unit 104 is also input to the motion compensation prediction unit 113.
[0013]
The quantized data is inversely quantized by the inverse quantization unit 110, subjected to IDCT (inverse orthogonal transform) by the IDCT unit 111, and the IDCT image data is input to the motion compensation prediction unit 113. The motion compensation prediction circuit 113 outputs a predicted image for the next inter coding.
[0014]
On the other hand, the quantized image data is input to the variable length encoding unit 109, subjected to variable length encoding, and input to the buffer 115. The image data in the buffer 115 is recorded on the recording medium 117.
[0015]
Next, in the case of inter coding, the switch 105 is connected to the B side. The image data output from the screen rearrangement unit 104 is input to the subtracter 106 via the switch 105, and the predicted image from the motion compensation prediction unit 113 is subtracted. This subtraction is performed in order to reduce redundancy in the time axis direction.
[0016]
The image data whose redundancy in the time axis direction is reduced by the subtracter 106 is input to the DCT unit 107 and orthogonally transformed. The orthogonally transformed image data is quantized by the quantizing unit 108 according to the quantization coefficient determined by the rate control circuit 116 according to the remaining amount of the recording medium 117. The quantized image data is input to the inverse quantization unit 110 and the variable length coding unit 109. The image data output from the screen rearrangement circuit 104 is input to the motion compensation prediction unit 113.
[0017]
The quantized data is dequantized by the dequantization unit 110 and IDCT is performed by the IDCT unit 111. The image data subjected to IDCT is directly input to the motion compensation unit 113 when the switch 2114 is turned off. When the switch 2114 is turned on, the adder 112 adds the predicted image from the motion compensation prediction unit 113 to a decoded image. This decoded image is input to the motion compensation prediction unit 113 for the next image encoding.
[0018]
The motion compensation prediction unit 113 outputs a predicted image and a motion vector. The motion vector is input to the variable length coding unit 109. In addition, a predicted image is output for the next inter coding.
[0019]
On the other hand, the quantized data is input to the variable length encoding unit 109, subjected to variable length encoding, and input to the buffer 115. The image data in the buffer 115 is subjected to error correction coding, digital modulation processing and the like by the recording circuit 117 and recorded on the disk 118.
[0020]
Next, rate control will be described with reference to FIG.
In general, the details of the relationship between the quantization coefficient and the data amount differ depending on the type of image, but the data amount decreases as the quantization coefficient increases.
FIG. 4A shows the relationship between the quantization coefficient and the data amount when the quantization coefficient is fixed. Although the amount of data varies depending on the image, the image quality is kept constant. This is variable rate coding (1).
[0021]
FIG. 4B shows the relationship between the quantization coefficient and the data amount when an upper limit is set for the data amount. Although the quantization coefficient is basically fixed, when the data amount exceeds the predetermined upper limit, the quantization coefficient is adjusted so that the data amount does not exceed the predetermined upper limit. This is limited variable rate coding (2).
[0022]
FIG. 4C shows the relationship between the quantization coefficient and the data amount when the data amount is constant. Although the quantization coefficient varies depending on the image, the recording rate is kept constant. This is fixed rate coding (3).
[0023]
In the present embodiment, the user can arbitrarily set the encoding mode by instructing these three modes from the operation unit 119. At this time, the rate control unit 116 calculates the remaining recording time according to the set encoding mode and the remaining recording capacity of the disk 118, and displays information on the remaining time on the display unit 120. The remaining amount of the disc 120 can be detected from TOC (Table Of Contents) data reproduced from the disc 120 by a reproducing means (not shown) when the disc 120 is inserted.
In the present embodiment, when the encoding mode (1) is selected, the mode is automatically switched according to the remaining amount of the recording medium.
[0024]
FIG. 5 shows changes in the recording rate with respect to the usage rate of the recording medium when the three recording rate control methods are switched according to the usage rate of the recording medium. Here, for example,

It is said.
[0025]
When the rate is controlled as described above, the user can determine at least how many minutes can be recorded by setting the upper limit of the recording rate by reducing the remaining amount of the recording medium while initially recording with priority on image quality. I can know. Further, since the remaining amount is further reduced and the recording rate is fixed, the user can accurately know the remaining recordable time. Also at this time, the rate control unit displays the remaining recordable time information on the display unit 120.
[0026]
Next, a storage medium according to another embodiment of the present invention will be described.
The present invention can be realized by a hardware configuration, but can also be realized by a computer system configuration including a CPU and a memory. When configured in a computer system, the memory constitutes a computer-readable storage medium according to the present invention.
[0027]
That is, a storage medium storing a program code of software for executing the operation described in the above embodiment is used in a system or apparatus, and a CPU of the system or apparatus reads out the program code stored in the storage medium, By implementing it, the object of the present invention can be achieved.
[0028]
Further, as this storage medium, a semiconductor memory such as ROM and RAM, an optical disk, a magneto-optical disk, a magnetic medium, etc. may be used, and these may be a CD-ROM, floppy disk, magnetic tape, magnetic card, nonvolatile memory card, etc. It may be configured and used.
[0029]
Therefore, the above-described embodiment can also be realized by using this storage medium in another system or apparatus other than the system or apparatus shown in FIG. 1, and reading and executing the program code stored in this storage medium by the system or computer. A function equivalent to that of the embodiment can be realized, an equivalent effect can be obtained, and the object of the present invention can be achieved.
[0030]
Further, when an OS or the like running on the computer performs part or all of the processing, or an extended function board in which a program code read from a storage medium is inserted into the computer or an extended function connected to the computer Even when the CPU or the like provided in the extension function board or extension function unit performs part or all of the processing based on the instruction of the program code after being written in the memory provided in the unit, it is equivalent to the above embodiment. In addition to realizing the above functions, the same effect can be obtained and the object of the present invention can be achieved.
[0031]
【The invention's effect】
As described above, according to the present invention, it is possible to accurately calculate the recordable time depending on the remaining amount of the recording medium while recording with priority on image quality. In particular, when the remaining amount of the recording medium is low, by recording at a constant recording rate, the user can accurately grasp the remaining recordable time and use the recording medium more effectively. Can do.
[Brief description of the drawings]
FIG. 1 is a block diagram showing a camera-integrated image recording apparatus according to an embodiment of the present invention.
FIG. 2 is a configuration diagram for explaining screen replacement.
FIG. 3 is a configuration diagram illustrating an encoding order.
FIG. 4 is a characteristic diagram for explaining rate control.
FIG. 5 is a characteristic diagram for explaining rate control according to the usage rate of a recording medium.
[Explanation of symbols]
103 Camera Signal Processing Unit 105 Switch 106 Subtractor 107 DCT Unit 108 Quantization Unit 109 Variable Length Coding Unit 110 Inverse Quantization Unit 111 IDCT Unit 112 Adder 113 Motion Compensation Prediction Unit 114 Switch 115 Buffer 116 Rate Control Unit 117 Recording Medium

Claims (7)

Encoding means for encoding the input video signal ;
Recording means for recording the encoded moving image data obtained by the encoding means on a recording medium;
Detecting means for detecting a remaining capacity of the recording medium;
When the remaining capacity of the recording medium is larger than a predetermined amount, the encoding mode of the encoding means is set to a first encoding mode in which the recording rate of the encoded moving image data does not exceed a specific upper limit, When the remaining capacity of the recording medium is smaller than a predetermined amount, the encoding mode of the encoding means is set to a second encoding mode in which the recording rate of the encoded moving image data is constant, and the set encoding Control means for calculating the time of a moving image recordable on the recording medium from the mode and the remaining capacity of the recording medium and displaying the time on the display device ;
An image recording apparatus comprising: Said encoding means, after orthogonal transformation and quantization of the motion image signal the input, image recording apparatus according to claim 1, characterized in that the sign-reduction. It said encoding means, an image recording apparatus according to claim 2, wherein the controller controls the recording rate by Rukoto changing the quantization step. The moving image signal, an image recording apparatus according to any one of claims 1 to 3, characterized in that a moving image signal captured by the imaging means. Further comprising an instruction means for manually instructing an arbitrary coding mode of said first encoding mode and the second encoding mode,
Said control means, an image recording apparatus according to any one of claims 1 to 4, characterized in that selecting the coding mode in response to an instruction of said instruction means. An image recording method in an image recording apparatus for recording encoded moving image data obtained by encoding an input moving image signal on a recording medium,
A detection step of detecting a remaining capacity of the recording medium;
When the remaining capacity of the recording medium is larger than a predetermined amount, the encoding mode is set to a first encoding mode in which the recording rate of the encoded moving image data does not exceed a specific upper limit, and the remaining capacity of the recording medium Is smaller than a predetermined amount, the encoding mode is set to the second encoding mode in which the recording rate of the encoded moving image data is constant, and the set encoding mode and the remaining capacity of the recording medium are used. A control step of calculating a time of a moving image that can be recorded on the recording medium and displaying the time on a display device;
Image recording method characterized by have a. The computer,
Encoding means for encoding the input video signal;
Recording means for recording the encoded moving image data obtained by the encoding means on a recording medium;
Detecting means for detecting a remaining capacity of the recording medium;
When the remaining capacity of the recording medium is larger than a predetermined amount, the encoding mode of the encoding means is set to a first encoding mode in which the recording rate of the encoded moving image data does not exceed a specific upper limit, When the remaining capacity of the recording medium is smaller than a predetermined amount, the encoding mode of the encoding means is set to a second encoding mode in which the recording rate of the encoded moving image data is constant, and the set encoding Control means for calculating the time of a moving image recordable on the recording medium from the mode and the remaining capacity of the recording medium and displaying the time on the display device;
Computer readable remembers medium storing a program for operating with.

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