JP2003250114A - Image recording apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To solve a problem of a conventional video camera recorder or video recorder that may have often brought about coding noises if an image to be inputted or a target object of a camera reaches a certain degree of complexity. <P>SOLUTION: A video compression coding means of the recording apparatus is provided with a means for displaying a fact of excess of a prescribed coding amount. A user can easily grasp a coding state with sense by employing the display means that varies the display depending on the complexity of an image received by the recording apparatus such that the display means displays the increased magnitude of the coding rate when the complexity of the image received by the recording apparatus is greater and on the contrary displays the decreased magnitude of the coding rate depending on the simplicity of the received image. Since the display means displays the varied magnitude of the coding rate depending on the complexity of the received image and the varied display color when the prescribed code amount is exceeded and the user can understand with sense that coding noises appear and coding with excellent performance is not executed, the user grasps it during recording and can avoid it when the user can adjust an object of the camera. Further, by displaying the remaining volume and the coding rate of the recording medium associated therewith, the decreasing pace of the remaining volume and the remaining time caused by recording may be notified to the user. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a technique for recording or reproducing video.

[0002]

2. Description of the Related Art As a reference technology for explaining the present invention, a DVD recorder DVR-1 made by Pioneer
There is an example as described on page 105 of the 000 type manual. As described in the reference example, it is described that the user of the recording apparatus can select the code compression rate of the recording apparatus and the selected state is displayed on the on-screen screen of the television connected to the outside. . It is also known to display the recordable time from the relationship between the remaining capacity of the disk medium and the recording coding rate.

However, the MPEG-2 standard MP @ ML, which is a device for compressing and encoding the above video signal and recording it.
(Main Profile @ Main Level)
In the device that adopts, the generated coding rate is 10 Mb.
It is difficult to set to ps or more. This is because, in particular, in the case of the disk recording device mentioned in the reference example, there is a problem that the recordable time becomes short in inverse proportion to the coding rate. Further, for MPEG-2 encoding, which is characterized in that the recording code rate can be set low compared to the case where the video signal is encoded without compression, the generated encoding rate is a high encoding rate such as 10 Mbps or more. The setting loses its characteristics. In the case of such a disk device, the recording coding rate is usually 5 to 7 Mb.
It is usually set to about ps, and such a coding rate is generally known as a coding rate with which an image quality usable in broadcasting can be obtained.

On the other hand, in the above video compression technique, it is known that the optimum coding rate after compression changes according to the complexity of the image input to the compression device, and the conventional recording method described above. If the upper limit of the recording coding rate is determined by selecting the compression rate as in the device, M
When an image of a complicated pattern is input to a stationary disk recorder equipped with a PEG-2 system image compression means, or when applied to a video camera, a very complex subject existing in nature is imaged by a lens. In addition, if a subject or a lens is dynamically moved to be photographed and recorded, the compressed image may generate coding noise. That is, in a device for digitally converting an input image and recording it on a recording medium such as a disc, particularly in the case of a video camera or a video recorder to which an optical disc is applied and using a high-efficiency encoding means called MPEG. Depending on the input image, unnatural noise called coding noise may be generated. The principle of generation of this coding noise will be described in "Embodiment of the Invention".

From the above description, if the range used as the recording coding rate is, for example, a device applying the above compression technology to a video camera, an object to be photographed, a stationary video recorder, Means for notifying the user whether or not the input video exceeds the upper limit of the recording coding rate becomes effective.

However, the specific coding rate display means as described above is not described in the above reference example.

[0007]

In a recording apparatus for digitally converting, compressing and coding a video signal and recording the same, at a normal recording coding rate, coding noise may occur depending on the complexity of the input video or the subject of the camera. It was mentioned above that this may occur. As a problem to be solved by the present invention, the user of the recording apparatus records the noise generated inside the encoding means in spite of the possibility that the above-mentioned encoding noise may occur. It is to solve the problem that the video cannot be known until it is decoded and played back. That is, the coding noise is generated according to the complexity of the image input to the operation panel or the display unit or the subject of the camera.
Or if there is a means to notify the user that it is likely to occur and the user can grasp this during recording and adjust the subject of the camera, adjust the state and position of the subject, the pattern, the background, etc. , Is to be able to avoid this. Alternatively, the above coding noise can be avoided by setting an optimum coding rate. However, when information is recorded on the recording medium, the recordable time varies depending on the coding rate. For example, if the coding rate is increased by capturing a complicated image, the capacity required to record information per unit time is increased. Therefore, for the unrecorded capacity (remaining capacity) of the recording medium, when recording at a large coding rate, the recordable time becomes smaller than when recording at a small coding rate,
The remaining time also becomes smaller. The remaining time increases or decreases as the coding rate changes. Usually, the remaining time is calculated by the following formula. (Remaining time) = (total capacity−written amount) / (encoding rate) Equation 1 In Equation 1, when the encoding rate changes, the remaining time also changes.
For example, if the coding rate in the subsequent recording becomes higher than the coding rate used to calculate the remaining time displayed at a certain point during recording,
This means that recording can be performed on the recording medium only for a time shorter than the remaining time displayed at a certain point during recording. In this case, the image to be recorded cannot be recorded due to the shortage of time, which is a problem. Therefore, it is necessary to devise a method of notifying the photographer of the remaining time, which is a problem.

[0008]

Means for solving the above-mentioned problems can be realized by providing display means for displaying that the video compression coding means exceeds a predetermined coding rate in the video recording apparatus. . Further, the display means increases the value of the display displaying the coding rate according to the complexity of the video input to the recording device, and conversely reduces the ease of input video. Accordingly, the value of the display displaying the coding rate is set to be small, so that the coding status can be grasped easily and intuitively. Also, by changing the display color of the display that displays the coding rate according to the complexity of the input video, similarly, coding noise is sensuously generated and good-performance coding is achieved. Since it can be understood that this has not been done, if the user can grasp this during recording and adjust the subject of the camera, this can be avoided.

This display means is usually an optical disk or H
A stationary video recorder to which a DD (hard disk) is applied can be displayed on a character panel capable of displaying a clock or the like, and a portable video camera can display it on a viewfinder or the like for optical framing.

By displaying the above display according to the input video, the user of the apparatus can avoid the coding noise in the digital video coding represented by MPEG-2 from occurring. It can be realized to offer the possibility. Further, in the notification of the amount of remaining time, when the coding rate fluctuates, the remaining coding time is calculated by using the maximum coding rate that can be used in coding as the coding rate of Expression 1 above. . In Expression 1, the remaining time calculated using the maximum coding rate is the minimum remaining time when recording is performed at the maximum coding rate.
Therefore, if there is a period for recording at a coding rate smaller than the maximum coding rate, the remaining time will be extended accordingly. However, at least the remaining time calculated at the maximum coding rate can be recorded.
However, the degree to which the amount of remaining time decreases decreases depending on the size of the coding rate. That is, if the coding rate is high, the amount of remaining time becomes small, and if the coding rate is small, the amount of remaining time becomes small. Therefore, by notifying the coding rate, the degree of decrease in the amount of remaining time can also be notified. Therefore, depending on the coding rate,
Remaining time amount display means for changing the display form showing the amount of remaining time that can be recorded on the recording medium is provided. That is, the size of the coding rate can be known by observing the change in the display form. For example, a means for changing the display color of the display according to the coding rate is provided. That is, the size of the coding rate can be known by looking at the display color. As a result, in the case of a display color with a high coding rate, it is possible to sensuously know that the amount of remaining time decreases to a large extent, that is, the amount of remaining time decreases rapidly.
On the other hand, in the case of a display color with a low coding rate, it is possible to notify that the amount of remaining time becomes small to a small extent and the amount of remaining time becomes small late. The display of the coding rate is not limited to changing the display color, but may change the blinking speed of the display mark or change the size of the display mark. In any case, the size of the coding rate can be notified by changing the display form. In addition to indicating the amount of remaining time by displaying a numerical value, the amount of recording or the time related to recording is shown in a strip bar graph, etc. To be displayed. At that time, if the coding rate is high, the speed at which the area indicating the recorded area sequentially increases increases, and if the coding rate is low, the speed at which the area indicating the recorded area sequentially increases increases slowly. By doing so, it becomes possible to notify the magnitude of the coding rate and the degree of decrease in the amount of remaining time. To explain the above notification in another way, the amount of the unrecorded area or the recordable time is indicated by a strip bar graph or the like, and the area of the unrecorded area is gradually reduced as it is recorded. indicate. At that time, if the coding rate is high, the speed at which the area of the unrecorded range gradually decreases is increased, and if the coding rate is low, the speed at which the area of the unrecorded range gradually decreases is decreased. By doing so, it becomes possible to notify the magnitude of the coding rate and the degree of decrease in the amount of remaining time. Alternatively, the notification may display the recorded range and the unrecorded range together. In this case, a band-shaped bar graph showing the total capacity of the recording medium or the like is displayed in a certain size, and as recording is performed, the range indicating the recorded state becomes larger and the range indicating the unrecorded area becomes smaller. May be displayed.
Here, the amount of remaining time that can be recorded on the recording medium means that the area where information is not recorded on the recording medium (unrecorded area) is
It is a recordable area in which information can be newly written, and indicates the amount of information that can be written in the recordable area. Therefore, the amount of remaining time does not mean only the time of a specific numerical value as shown based on the unit of hours, minutes, seconds, and the like. For example, in the recording medium, when a recorded area which has already been recorded and an unrecorded area which has not been recorded yet are displayed, from the ratio of the displayed size of both, for example, it is still The size of the unrecorded area that has not been recorded can be relatively displayed. In other words, in the case of this display, the time of a specific numerical value as shown based on the unit of hours, minutes, seconds, etc. is not used, but the amount of remaining time that can be recorded on the recording medium is displayed. It is assumed that

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS For example, when the present invention is applied to a digital video signal recording / reproducing apparatus, a stationary optical disk recording apparatus for mainly recording a TV program as described above or an HDD ( Hard Disk Dr
A recording device using iv) is conceivable. A portable video camera recorder has also been developed using the above recording medium, and it has become possible with the latest miniaturized LSI technology and miniaturized optical pickup. Especially in a video camera, the image to be recorded, that is, the subject is valuable to the user of the video camera, and is often used when an extraordinary event occurs. Is often emphasized.

A video camera using the digital compression technology currently developed includes a 12 × zoom lens, a 10 × zoom lens, and a 10 × zoom lens.
CCD sensor with 0.1 to 1.2 million pixels, 0.18 μm
Camera signal processing using CMOS technology, MPEG-2 system as digital encoding system, 8 cm as recording medium
Size DVDRAM (DIGITAL Versat
ile Disc Random Access Memo
ry) has been put to practical use.

In the case of a video camera, the subject and the video to be recorded are basically set by the photographer, rather than recording a prerecorded program (program), and the opportunity for photographing is limited. It is necessary to surely record good image quality. In addition, the image finder in a video camera generally outputs a video image through a camera signal processing circuit, but a camera that has been developed in the past can check whether or not coding noise occurs during compression coding. There is no notification to the photographer. However, according to the present invention, it is possible to confirm whether or not coding noise is generated by performing shooting such as trial shooting before shooting, and it can be used as a reference when selecting a coding rate or by a photographer. It becomes possible to adjust the subject.

In this example, a digital video camera will be described in detail.

FIG. 1 is a circuit block diagram of a video camera for digitally converting an input image and recording it by using the MPEG-2 system. Reference numeral 1 is an optical disk recording medium such as a DVD, which has a diameter of 12 cm in general, but since the recording method is from the inner circumference of the disk, a small disk has been devised, and an 8 cm size is standardized. Has been done. The optical disc may be mounted on the camera only by the disc, but for the purpose of protecting the disc, the optical disc is put in a case conforming to the outer shape of the disc and is mounted together with the case. Reference numeral 2 is a pickup capable of writing and reading signals of an optical disc such as a DVD. Reference numeral 3 is an operation key for performing recording and reproduction, and 7 is a CCD image pickup element + AGC circuit + AD conversion circuit for converting light imaged from an optical lens into an electric signal, automatically adjusting an amplitude level, and converting into a digital signal. 4 is a DVD optical disc integrated with a tracking, focus and disc spindle servo circuit and an error correction circuit for writing and reading data, and 8 is a camera signal processing D
SP circuit, 10 is a camera control microcomputer, 11 is MPEG
-2 codecs, 13 is a system control microcomputer, and 15 is a viewfinder capable of displaying a subject image and a reproduced image obtained from a lens, and is generally composed of a liquid crystal panel such as an LCD. The LCD display panel 15 has a diagonal size of 2 inches to 4 inches, and its contents can be easily confirmed when the image on the disc is reproduced. Reference numeral 2 is a pickup capable of writing and reading signals of an optical disc such as a DVD.

Next, with reference to the circuit block diagram of the video camera shown in FIG. 1, the flow of signals at the time of shooting and the processing of each block will be described.

The subject image obtained from the optical lens is CC
After being photoelectrically converted by the D image pickup element + AGC circuit + AD conversion circuit 7, a change in the signal level in the optical system is set to a predetermined signal level by the AGC circuit, and after being AD converted into a digital signal because of an analog signal,
It is input to the camera signal processing DSP 8. The signal obtained from the CCD image pickup device + AGC circuit + AD conversion circuit 7 is CC
Since the read signal is generated according to the physical arrangement of the D sensor, the camera signal processing DSP 8 outputs Y, U, and
While being converted into a V signal, the image is enhanced and output. The camera signal processing DSP 8 is a CCD
A drive pulse required for the image sensor + AGC circuit + AD conversion circuit 7 and a synchronization signal required for video output are generated and supplied to each unit. At this time, although not shown, the camera control microcomputer 10 which is a camera control unit, zooms and focuses the lens, and image information obtained from the CCD image pickup device + AGC circuit + AD conversion circuit 7, and the operation keys 3.
The camera signal processing DSP 8 is optimally controlled by the information obtained from the above. Further, although not shown, an analog output such as an angular velocity sensor using a gyro sensor or the like is AD-converted and then taken into the camera control microcomputer 10 so as to obtain an image with less camera shake by controlling the drive pulse of the CCD image pickup device. I have to.

The digital image signal obtained from the camera signal processing DSP 8 is sent to the MPEG-2 codec 11 as, for example, 16-bit parallel data in this example. The MPEG-2 codec 11 uses the memory 12 as an image memory and develops the image of the camera signal processing DSP 8 to convert moving image data to about 1/6 according to the MPEG-2 format.
Compress to about 0. The compressed image data is output to the system internal bus 5 according to an instruction from the system control microcomputer 13. On the other hand, although the audio signal is not shown, a signal obtained from a microphone built in the camera is AD-converted and compressed by software in the system control microcomputer 13 to generate an MPEG audio stream. On the other hand, the image data output by the MPEG-2 codec 11, the image stream and the audio stream in the system control microcomputer 13 are multiplexed by software to generate an MPEG data stream. This MPEG data stream is a DVD
Temporary MPE is performed by the buffer RAM 6 for avoiding a write error such as a scratch in the optical disk or a seek of the head, which temporarily stops writing.
The G stream is stored for several seconds and is sent to the DVD optical disc signal processing circuit composed of the DVD error correction servo circuit 4 and the DVD RF data R / W circuit 16 via the system internal bus 5. Reference numeral 4 is an integration of a tracking, focus and disc spindle servo circuit for a DVD optical disc and an error correction circuit for writing and reading data, and the MPEG data stream is DV.
The data is processed by the D error correction servo circuit 4 into a data format according to the DVD standard, a correction code is added, and the DVD R
Digital modulation is performed by the F data R / W circuit 16 and recorded on the DVD optical disc 1 by the pickup 2.

Next, the case of reproducing image data from the DVD optical disk 1 will be described. Basically, a signal flows in the reverse of the above recording state. First, the pit information in the DVD optical disc 1 is read by the pickup 2 from the DVD optical disc 1 in a digitally modulated state, and the DVD RF
The data R / W circuit 16 detects waveform equalization and servo signals, and the DVD error correction servo circuit 4 detects MPEG.
-2 is output to the system internal bus 5 as an image stream. For the image and audio data of the system internal bus 5, the data transfer on the bus is controlled by the command of the system control microcomputer 13, and the MPEG-2 codec 1
The original image data is restored by decompression operation by 1,
Camera DSP8 with 16-bit parallel signal as well as recording
After being converted into a video signal such as an NTSC or PAL signal by, the image is displayed as a reproduced image on the LCD display panel 15 through the character generation unit 14 for generating on-screen characters and the LCD control unit 9. Similarly, since the camera signal processing DSP 8 outputs an NTSC or PAL video signal, it can be displayed on an external display device from the video output terminal. Here, it has been described that a moving image according to the MPEG-2 system is recorded and reproduced, but this camera can also capture and record a still image according to the JPEG system. JPEG encoding operation is MPEG
The operation is almost the same as the I-picture encoding operation of the system, and the MPEG-2 codec 11 can also perform the JPEG encoding operation by switching a part of the operation of the circuit. The still image output from the MPEG-2 codec 11 is recorded on the DVD optical disc 1 as one file.

FIG. 1 shows a video camera to which the present invention is applied.
The image signal obtained from the CCD image pickup device + AGC circuit + AD conversion circuit 7 of the camera of FIG.
MPEG- which is highly efficient coded according to the PEG-2 standard
The operation in the 2-codec 11 and the operation in the system control microcomputer 13 that drives and controls it are important. The system control microcomputer 13 controls the MPEG-2 codec 11 to start recording and generate MPEG-2 data at a predetermined coding rate when a user of the video camera operates the operation key 3. There is a need. Also, always DV
The system control microcomputer 13 grasps the remaining capacity of the D optical disk 1 via the DVD error correction servo circuit 4, and the estimated remaining recordable time is displayed on the LCD display panel 15 or the like for the user of the video camera. Need to show.

FIG. 2 is a circuit block diagram showing the inside of the MPEG-2 codec 11 in detail. MPEG-2
Codec unit 11 and system control microcomputer 1
3, the part that controls the coding rate will be described in detail.

In a video camera using the MPEG-2 system, in order to improve the image quality of an image to be recorded, the input image has a large motion component and many high frequency components in the horizontal and vertical directions in the video signal, that is, a so-called complicated image. In the case of a pattern, the rate control circuit 24 is operated according to the input image,
It is generally known to record while sequentially changing the coding rate. At this time, for example, it is necessary to perform recording at a coding rate higher than the coding rate so that an image quality sufficient for a home video camera can be obtained. The system internal bus 5 and the system control microcomputer 13 are the same as the system internal bus 5 and the system control microcomputer 13 in FIG. Figure 2
In FIG. 1, the MPEG-2 codec 11 is a part surrounded by a frame, and shows the internal block of the MPEG-2 codec 11 of FIG. Camera signal processing D in FIG.
The digitized image data of SP8 is input to the video conversion circuit 160, and MP @ ML of the MPEG-2 standard is used.
(Main profile at Main Level
The data is converted so that it can be easily encoded according to l). The image data output from the video conversion circuit 160 is input to the motion detection / prediction circuit 18, the motion information of the image data is detected, and the motion vector is extracted. The extracted motion vector is added to the motion compensation circuit 23, and the motion compensation circuit 23 uses the motion vector obtained from the motion detection / prediction circuit 18 to shift a temporally preceding and following image by a motion amount, and a reference image. Generates difference data from the reference image extracted from the image data, called a template,
DCT (Discrete Cosine Transf)
orm) circuit 19 is added to the frequency conversion circuit. At this time, the image data is transferred from the video conversion circuit 160 to M
It is added to the image memory 12, the motion detection / prediction circuit 18, and the motion compensation circuit 23 via the system internal bus 5 connected to the inside of the PEG-2 codec 11. Reference numeral 22 is a data compression determination circuit having a function of selecting the most efficient image frame when detecting the difference in the amount of motion of the image.
The DCT circuit 19 can extract the frequency component of the image by performing the DCT operation on the image signal. When a screen with a large flat area, that is, an image with a low frequency component is input to the input image, the DCT circuit 19 As output, image data concentrated on low frequency components can be obtained. On the other hand, when a screen having many fine parts is input to the input image, the output of the DCT circuit 19 is image data in which many high frequency components are generated. The quantizing circuit 20 is a part for digitally thinning and quantizing the image data decomposed into frequency components output by the DCT circuit 19, particularly for a high frequency portion, and the thinning amount is reduced to output by the DCT circuit 19. If the image data is faithfully quantized, a high-definition image faithful to the input image can be obtained. On the contrary, if the thinning interval is widened, the generated coding rate is reduced and the compression rate of the entire MPEG-2 codec 11 is improved, but the image quality is deteriorated. At this time, when the present invention is applied to a recording / reproducing apparatus such as an optical disc, the usable coding rate is limited as described above. For example, in the case of a home video camera, the coding rate is limited to 6 Mbps. , If the input image is a complicated video, the above quantization is D
The image data output from the CT circuit is thinned out, the fidelity to the input image is reduced, and a phenomenon called so-called coding noise occurs. Since this encoding noise causes image data handled by the DCT circuit 19 to be in units called macroblocks, luminance distortion, that is, a luminance step, occurs between macroblocks, resulting in discontinuous encoded images. It is known as an unpleasant thing because it becomes an image that does not exist in nature. Next, VLC (Variable Length Cod)
e) The circuit 21 is a circuit for compressing the quantized code according to a rule called variable-length coding, and the output of the VLC circuit 21 finally becomes recording data to be recorded on a recording medium such as an optical disk. At this time, the system control microcomputer 13 uses the MPEG-2 codec 1
It is necessary to control the coding rate per unit time that all 1 occurs. The system control microcomputer 13
The video recording / reproducing apparatus as a whole sends an instruction to the rate control circuit 24 to control the data thinning amount of the quantization circuit 19 in accordance with the coding rate at which the image quality of the home video camera can be obtained sufficiently. Here, the system control microcomputer 13 constantly monitors whether or not the quantization circuit 20 has exceeded the thinning-out amount at which the above coding noise is likely to occur. In the program area of the system control microcomputer 13, for example, a decimation amount that is 20% higher than the decimation amount at the encoding rate of 6 Mbps that is normally recorded is set, and, for example, MPEG GOP (Group).
Information is acquired from the rate control circuit 24 for each Of Picture), and comparison judgment with the set thinning amount is performed to judge whether or not the area is in a region where coding noise is likely to occur. When it is detected that this area has been entered, a predetermined command is output to the system internal bus 5 to control the display drive circuit 17 to turn on the red LED on the display circuit 50 composed of, for example, an LED. Give instructions. This allows the user of the video camera to know whether or not there is a problem in image quality in the current shooting situation from the viewpoint of coding noise. For example, in the area where a stable image is obtained, which is less than the area where the coding noise is likely to occur, the LED is turned green or turned off,
It is also possible to notify the user of the recording state. As a result, the user selects a subject, stabilizes the camera, or switches the encoding rate of the video camera, that is, selects the image quality switching mode so that the LED is always off or the green state is maintained. Can be the reference. A user-preferred image that is valuable to the user is not degraded by coding noise, and if the user and the user's subject allow it, once try recording in a low coding rate mode,
It is also possible to recognize that the display has turned red, switch the coding rate to the higher one, and take the image again.

Here, although different from the method of FIG. 2, a method not using the display drive 17 and the display 50 can be considered. As shown in FIG. 1, a video camera usually has an LCD.
Since the display panel 15 and the character generation unit 14 are used, the information detected by the MPEG-2 codec 11 and the system control microcomputer 13 is transmitted to the camera control microcomputer unit 10 by inter-microcomputer communication using the display panel 15 and the character generation unit 14. It is possible to control 14 to display the state of the coding rate on the LCD display panel 15. According to this, the display function of the present invention can be provided without adding any new hardware.

In the case of the present embodiment, a CBR (Constant Bit Rate) system for recording at 6 Mbit / s is provided due to the limitation of the recording time by the capacity of 1.46 GB of the 8 cm type optical DVD disc and the image quality required for the home video camera. Has been. On the other hand, VBR (Variable Bit Rate) that sequentially changes the coding rate
The mode has a mode of recording at a maximum of 8 Mbits and a minimum of about 4 Mbits according to the movement and complexity of the image to be recorded. Here, a device that compresses and encodes a video signal and records it, particularly MP @ ML (Ma of the MPEG-2 standard).
In Profile @ Main Level), an optical disc with a recording capacity of about 4.7 GB on one side and a small 8 cm type optical disc with a recording capacity of about 1.46 GB on one side can be used in Constant Bit Rat
It is difficult to set the e coding rate to 10 Mbps or higher. This is because it takes about 1 hour or less for an optical disc of about 4.7 GB and about 18 minutes for a small disc of 1.46 GB, and a practical recording time is required for a video camera employing a small disc of 1.46 GB. Because there is. At this time, it is usual to set the recording coding rate to about 5 to 7 Mbps.
It is known as a recording coding rate at which an image quality that can be used for broadcasting is obtained at about Mbps.

Next, the display function of the present invention is
How it operates according to the input image will be described with reference to FIG. When a complex and dynamic image is input as in 27 of FIG. 3, a CBR (Vari) such as 28 is input.
Since the coding rate to be recorded cannot be increased in the “Able Bit Rate” mode, the above coding noise is likely to occur. In addition, VBR (Variab) such as 25
Even in the le Bit Rate mode, it is difficult to set it to 10 Mbps or more due to the practical limitation of the recording time as described above. Therefore, no matter how the code rate for recording is increased, a specific image existing in nature is input. Then, coding noise may occur. Reference numeral 29 is a line indicating a threshold value for determining whether or not coding noise, which is a feature of the present invention, is likely to occur, and in this example, it is set to about 7 Mbps. For example, VBR (Variable)
When the bit rate) coding rate 25 records a complex and dynamic image, it may exceed 29 lines. If this is exceeded, the system control microcomputer 13 in FIG. Group
It becomes possible to acquire the information from the rate control circuit 24 for each Of Pictures and make a determination, control the display drive circuit 17, and notify the user of the video camera of the information that the recording is not good.

Next, FIG. 4 shows a display function of the present invention.
6 shows an example of a liquid crystal monitor screen of a home video camera provided with a PEG-2 codec or a display screen of a viewfinder for framing an object.
Reference numeral 36 is a display showing operation modes such as recording operation and reproduction operation, and 37 is a program AE mode for operating automatic control such as exposure control and shutter speed control according to the object of the subject or photographer. Showing 3
A camera using an optical disk or the like as a recording medium 8 can record a large amount of still images. Therefore, not only moving images of general video cameras but also still images can be recorded as "moving images / still images". Switching operation mode display, 39 is a zoom bar display that appears when zooming the optical lens or electronically zooms, 45 is a display that indicates mode selection of the recording coding rate, and 50 is a display that is a feature of the present invention. In the present embodiment, when the complexity of the normal subject or the image input to the camera is small, the display bar of 50 is displayed in white or green, and the complexity of the image input to the camera becomes complicated. , When the camera is in the recording state and encoding is performed in a state where encoding noise occurs, the display bar of 50 moves to the right and the entire color changes to red or magenta, It is obtained by as a warning to the user. 41 is the date and time of shooting, 4
2 indicates the remaining capacity of the battery, 43 indicates the remaining recording time of the recording medium, and 44 indicates the elapsed time from the start of recording.

Here, the user of the camera looks at the state of the display 50 and changes the angle of view of the subject, or avoids, for example, if there is a complex object with many high frequency components in the background of the subject. You can also take a picture. Also, for example,
A video camera to which the present invention is applied is a Constant Bi
Even if the recording is performed by t Rate, if the target coding rate can be switched, the user of the camera often looks red while viewing the display 50.
It is also possible to raise the target value of the Constant Bit Rate to some extent. In addition, although it is a sensational effect, the presence of the display 50 also has an effect of providing a sense of security that effective shooting is possible even if there is only one shooting opportunity.

In comparison with the example applied to the viewfinder of FIG. 4, FIG. 5 is provided with a display lamp having the same function as the display 51 around the viewfinder or in the operation panel, for example, constituted by LEDs emitting two colors. It shows the case. Although the function is exactly the same as in the case of FIG. 4, it is possible to more effectively recognize the function by providing it in the periphery of the viewfinder rather than in the viewfinder. In other words, it is possible to continue shooting while more clearly monitoring whether or not the shooting state is good. Of course, display 50
Since the display 51 and / or the display 51 may not need to be monitored, there may be an operation mode of "display off" so that the display 50 and / or the display 51 does not function.

Although the example of FIGS. 4 and 5 shows an example in which the present invention is applied to a home video camera, it may be applied to, for example, a stationary video recorder. For example, a notification such as display 50 and / or display 51 during recording of the video recorder allows the user of the video recorder to optimally select the recording coding rate of the video recorder. The effect of adjusting the recording level while monitoring the audio recording level of the conventionally known audio recording deck with the display meter can be obtained. In the above embodiment, the user is notified that the coding noise is occurring or is likely to occur depending on the complexity of the input image or the subject of the camera. Grasp this during recording,
In order to avoid this, if the coding rate can be switched, the coding rate can be switched and adjusted so that coding noise is less likely to occur. It goes without saying that this is carried out in the information recording device including the above-mentioned home video camera, stationary video recorder and the like.

Next, an embodiment of how to display the remaining amount will be described. FIG. 6 shows a flowchart for obtaining the remaining time. In FIG. 6, it is determined in S1 whether or not recording is in progress. If recording is in progress, the process proceeds to S2, and if not, the process proceeds to S5. If recording is in progress, the amount actually written on the disc is obtained in S2, and the coding rate is obtained in S3. Then, in step S4, the remaining time is calculated by the above equation 1. When the coding rate fluctuates, the calculation is performed using the maximum usable coding rate, and therefore the minimum remaining time that can be recorded is always calculated.
If recording is not in progress, a free disk space is acquired in S5. Then, in S3, the coding rate is acquired, and in S4, the remaining time is calculated by the above equation 1. As a result, even when the coding rate is changed while the recording is stopped, the remaining time according to the coding rate can be obtained. The remaining time calculation routine described above is performed at a certain time interval, for example, every second or
By carrying out every 1/60 second, it becomes possible to accurately determine the remaining time. Although the coding rate is acquired in S3, the acquisition is not limited to the acquisition at the position shown in FIG. However, it is necessary to acquire the coding rate before calculating the remaining time by the above Expression 1 in S4. Also, the coding rate is not necessarily required to be acquired. For example, a flag indicating that the coding rate has changed may be provided when the coding rate has changed, and the coding rate may be acquired when the flag has changed. By doing this, as long as the flag does not change,
With the same coding rate, the remaining time may be calculated by the above equation 1 in S4.

Next, a description will be given of an embodiment in which the coding rate is displayed and the degree of decrease in the remaining time is sensuously displayed. FIG. 7 illustrates, for example, a viewfinder of a camera displaying the remaining time. Reference numeral 70 is a recorded portion, 72 is a recording head portion, 74 is an unrecorded portion, 76 is an elapsed time from the start of recording, and 78 is a remaining time of the recording medium. In FIG. 7, when the color of the recording head portion 72 is high, for example, the color is red, and when the color is low, the color is blue. The display is easy to understand. As the recording progresses, the recording head portion 72 moves to the right and the unrecorded portion 74 becomes smaller successively.
When the coding rate is high, the recording head portion 72
Moves to the right earlier and the recording head 72 moves to the right later when the coding rate is small, the degree of decrease in the remaining time can be displayed in an easy-to-understand manner.

8 and 9 similarly display the remaining time. Reference numerals 80 and 90 indicate recorded portions, 82 and 92 indicate recording beginning portions, 84 and 94 indicate unrecorded portions, 86 and 96 indicate elapsed time from recording start, and 88 and 98 indicate remaining time of recording medium. is there. In FIG. 8, the width of the recording head portion 82 is made thick when the coding rate is large, and in FIG. 9, when the coding rate is small, the width of the recording head portion 92 is made thin so that the coding rate The size is displayed by the width of the recording head portions 82 and 92 so as to be intuitively understood. Of course, also in FIGS. 8 and 9, as in FIG. 7, when the coding rate is high, the recording heads 82 and 92 are
If the recording heads 82 and 92 are moved to the right earlier and the coding rate is smaller, the recording heads 82 and 92 are moved to the right later, so that the degree of decrease in the remaining time can be displayed in an easy-to-understand manner.

According to the above embodiment, by displaying the remaining amount display of the unrecorded area of the recording medium and the coding rate in association with each other, the degree of decrease in the remaining amount and remaining time due to recording is notified in an easy-to-understand manner. It becomes possible to do. For example, when an image is recorded in an imaging device such as a camera, the amount of remaining time that can be recorded on a recording medium is also adjusted based on the notified remaining time and the degree of decrease in the amount of remaining time. The photographer can intuitively predict. Therefore, it becomes possible to prepare for the replacement of the recording medium based on the amount of the remaining time that is sensuously predicted, and the usability is improved even in the recording in which the variation of the coding rate occurs.

In the configuration of the above embodiment, the display means may be used to indicate the magnitude of the value of the coding rate, or the magnitude of the value of the coding rate of the coding means. It is also possible to provide a coding rate display means for indicating the level. Further, in the above-mentioned configuration, the remaining time amount indicating the amount of remaining time that can be recorded on the recording medium may be displayed by the display means,
Alternatively, the amount of remaining time that can be recorded on the recording medium may be displayed by the remaining time amount display means.

When the display form on the encoding rate display means or the remaining time amount display means is changed according to the magnitude of the value of the encoding rate, the value of the encoding rate is set to a predetermined value. A means for comparing may be provided. However, the means for comparing the value of the coding rate with a predetermined value may be one that is processed inside a control means such as a system control microcomputer that controls signal processing and the like in the video recording device.

Further, the hardware necessary for the embodiment according to the present invention is constituted by using a device for performing a basic operation of a video camera which applies an optical disk or the like in an example of displaying on a viewfinder at the time of photographing, There is no particular cost increase. The software is smaller in program capacity than the firmware for controlling the optical disc and the software for searching the inside of the optical disc.

In the above embodiments, the recording medium is an optical disk or HDD, but the recording medium is not limited to this, and it goes without saying that the recording medium such as a memory can be used.

[0038]

By applying the present invention, it is possible to provide means for avoiding unnatural noise called coding noise, and especially for users of video cameras and video recorders that apply optical disks, less noise than before. There is an effect that a recorded / reproduced image can be obtained. Further, by using the present invention, it is possible to notify the degree of decrease in the remaining amount.

[Brief description of drawings]

FIG. 1 is a circuit block diagram of a video camera to which an optical disc is applied.

FIG. 2 is a circuit block diagram of an MPEG-2 encoder.

FIG. 3 is a diagram showing characteristics of an encoding rate for an input image.

FIG. 4 is a diagram showing a display example of a recording finder of a video camera using the present invention.

FIG. 5 is a diagram showing an example of a display lamp of a video camera using the present invention.

FIG. 6 is a diagram showing a flowchart of remaining time calculation.

FIG. 7 is a diagram showing an example of a remaining time display using the present invention.

FIG. 8 is a diagram showing an example of remaining time display using the present invention.

FIG. 9 is a diagram showing an example of a remaining time display using the present invention.

[Explanation of symbols]

1 ... DVD type optical disk, 2 ... Optical pickup, 3 ...
Operation keys, 4 ... Error correction servo circuit, 5 ... System internal bus, 6 ... Buffer RAM, 7 ... CCD image sensor + AG
C circuit + AD conversion circuit, 8 ... Camera signal processing DSP, 1
DESCRIPTION OF SYMBOLS 1 ... MPEG-2 codec signal processing circuit, 13 ... System control microcomputer, 15 ... LCD finder, 18 ... Motion detection prediction circuit of input image, 20 ... Quantization circuit, 23 ... Motion compensation which extracts the difference between frames of a moving image Circuit, 24 ... Encoding rate control circuit, 25 ... Variable encoding rate VBR (Variable Bit Rat)
e) Coding characteristics of mode, 28 ... Characteristics of CBR (Variable Bit Rate) mode coding when the coding rate is fixed, 70, 80, 90 ... Recorded portion,
72, 82, 92 ... Head of recording, 74, 84, 94 ...
Unrecorded area, 76, 86, 96 ... Elapsed time from recording start, 78, 88, 98 ... Remaining time of recording medium.

─────────────────────────────────────────────────── ───

[Procedure amendment]

[Submission date] April 10, 2002 (2002.4.1)
0)

[Procedure Amendment 1]

[Document name to be amended] Statement

[Name of item to be corrected] 0002

[Correction method] Change

[Correction content]

[0002]

As the important reference techniques in describing the Related Art The present invention, to be able to select a code compression rate users recorder, displaying the selected state to the television on-screen display on which is connected to an external What is known is. In addition, it is known to display the recordable time from the relationship between the remaining capacity of the disk medium and the recording coding rate.

Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) H04N 5/225 H04N 5/91 L 5/92 5/92 H 7/24 7/13 Z (72) Inventor Yaji Shigeru Fumi 1410 Inada, Hitachinaka City, Ibaraki, Ltd. Digital Media Products Division, Hitachi, Ltd. (72) Inventor Morio Aoki 1410 Inada, Hitachinaka City, Hitachinaka City, Ibaraki F-Term (Reference) 5C022 AC01 AC12 AC13 AC18 5C053 GA11 GB21 GB22 GB38 LA02 5C059 KK01 LA01 MA00 MA05 MA23 ME01 NN01 PP01 PP04 PP14 RC32 RF05 SS13 SS14 TA45 TB03 TC10 TC15 TC24 TC38 TC47 TD11 UA02 UA31 UA33 5D044 AB05 CC07A04 G05 AB03 BC04 BC04 BC05 BC04 BC04 BC04 HA07 HC09 HC23 HC50

Claims (20)

[Claims] 1. A video recording apparatus comprising a coding means for coding a video signal and a recording means for recording the coded information obtained from the coding means on a recording medium, wherein a coding rate of the coding means. The video recording apparatus is characterized in that a coding rate display means for indicating the magnitude of the value of is provided, and the display form of the coding rate display means is changed according to the magnitude of the value of the coding rate. 2. The video recording apparatus according to claim 1, wherein the value of the coding rate of the coding means is compared with a predetermined value to change the display form of the coding rate display means. Video recording device. 3. The video recording apparatus according to claim 1, wherein the display color indicating the magnitude of the value of the coding rate of said coding rate display means changes. 4. The video recording apparatus according to claim 1, wherein the value of the coding rate of said coding rate display means changes in accordance with the value of the value of said coding rate. Video recorder. 5. The video recording apparatus according to claim 1, further comprising: a remaining time amount display means for indicating an amount of remaining time that can be recorded on the recording medium, wherein: A video recording apparatus, wherein the display form of the remaining time amount display means is changed. 6. The video recording apparatus according to claim 5, wherein the value of the encoding rate of the encoding means is compared with a predetermined value, and the display form of the remaining time amount display means is changed. Video recorder. 7. The video recording apparatus according to claim 5, wherein the display color indicating the amount of remaining time of said remaining time amount display means is changed. 8. The video recording apparatus according to claim 5 or 6, wherein the display amount of the remaining time amount display means changes based on the information amount of the encoded information recorded on the recording medium. A video recording device characterized by the above. 9. The video recording apparatus according to claim 5, wherein the color displayed by said remaining time display means is changed according to the value of said encoding rate. Recording device. 10. The video recording apparatus according to claim 5, wherein the size of the display indicated by said remaining time amount display means is changed according to the value of said encoding rate. Video recording device. 11. The video recording apparatus according to claim 5 or 6, wherein the number of blinks per unit time of the display indicated by the remaining time amount display means is changed according to the value of the encoding rate. Video recording device characterized by. 12. A video recording apparatus according to claim 1, further comprising a camera optical system, a camera signal processing means, a finder means for looking at an object, and a power supply circuit. . 13. A video signal is compression-encoded, and in the video compression encoding, there is provided compression encoding means capable of varying the encoding rate according to the complexity of the video signal, and the video compression-encoded code is recorded. In the video recording device that stores in the medium,
A video recording device comprising a display means for displaying whether the coding rate of the coded video signal is higher or lower than a predetermined coding rate. 14. The apparatus according to claim 13, wherein when the coding rate of the video compression coding means increases in accordance with the complexity of the video, the display value for displaying the coding rate is large. The video recording apparatus is characterized in that, when the coding rate of the video compression coding means becomes smaller according to the simplicity of the video, the display value for displaying the coding rate becomes smaller. 15. The apparatus according to claim 13, wherein when the coding rate of the video compression coding means increases according to the complexity of the video and exceeds the predetermined coding rate, A video recording device characterized in that the display color displaying the coding rate changes. 16. The apparatus according to claim 15, wherein when the coding rate of the video compression coding means increases according to the complexity of the video and exceeds the predetermined coding rate, An image recording device characterized in that the display color displaying the encoding rate changes to red. 17. A video is compression-encoded and the compression rate of the video compression means is varied according to the complexity of an input video signal, so that the coding rate is fixed regardless of the complexity of the video signal. In a video recording apparatus having a compression encoding means for storing the video compression encoded code in a recording medium, a display means is provided for displaying whether the compression rate is higher or lower than a predetermined compression rate. Video recording device. 18. A video recording apparatus according to claim 13, wherein said recording apparatus comprises an optical lens, a camera signal processing means, a finder means for determining an angle of view of an object, and a battery. 19. The apparatus according to claim 17, wherein the compression rate of the video compression coding means becomes higher according to the complexity of the video and exceeds the predetermined compression rate. A video recording device characterized in that the display color displaying is changed. 20. The apparatus according to claim 17, wherein the compression rate of the video compression encoding means is increased in accordance with the complexity of the video and exceeds a predetermined compression rate. An image recording device characterized in that the display color being displayed changes to red.