JP3208034B2 - Video monitoring method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a moving picture monitoring method , and more particularly to a technique for processing moving picture data which handles a compressed moving picture signal recorded on a digital storage medium.

[0002]

2. Description of the Related Art A variable-rate disk system is described in detail in "Proceedings of the 1994 Annual Conference of the Institute of Television Engineers of Japan", pp. 285-286, published by The Institute of Television Engineers of Japan on July 27, 1994. I have.

[0003]

However, according to the above-mentioned prior art, a method of copying recorded contents of a disk encoded at a variable rate to another digital recording medium at a high speed, and a method of monitoring an image while copying at a high speed. Nothing is said about how to do it.

By the way, when handling a disk having the recording content encoded at such a variable rate, it is possible to copy the recording content of the disk encoded at the variable rate to another digital recording medium at a high speed. In order to be able to monitor the contents of moving images, etc. that are currently being recorded while copying at high speed,
It is considered to be a much-coveted technique for shortening the processing time and improving the convenience of handling.

[0005] The present invention has been made in view of the above points,
And has an object, the recorded contents of the disc which is encoded by a variable rate, in high Hayako copy to another digital recording medium, to make it possible to monitor the contents of the moving image or the like which is currently recorded is there.

[0006]

In order to achieve the above-mentioned object, in accordance with the complexity of a picture or a group of pictures, the data obtained when digitally compressing the picture or the group of pictures to generate a bit stream is described. A bit stream is reproduced at a fixed data rate by a reproducing apparatus from a digital storage medium on which a moving image digitally compressed so that the rate is temporally changed is recorded, for example, an optical disk, and the reproduced bit stream is stored in the digital storage medium. On the receiving side transmitting from a transmission side having a transmission medium, for example, a cable, and receiving the transmitted bit stream, a digital storage medium, for example, an optical disk, a magnetic disk, a magnetic tape, or the like, at the fixed data rate, Record bitstream Sea urchin, composed.

At the same time, data is thinned out in units of the picture or picture group from a bit stream of a fixed data rate received by the receiving side.
It is configured to decode the remaining bit stream and continuously reproduce moving images that are temporally skipped.

[0008]

According to the complexity of the image, the digital image is compressed and reproduced so that the quality of the moving image becomes constant.
An optical disk on which a bit stream generated by digital compression so as to change the data rate when converted into a bit stream by digital compression (hereinafter referred to as “variable rate encoded” in the present invention) is recorded in a variable Play at a fixed rate using the highest bit rate in the range. The reproduced signal is transmitted through a transmission medium such as a cable, and the transmitted fixed-rate bit stream is recorded on an optical disk, a magnetic disk, a magnetic tape, or the like. This makes it possible to perform high-speed copying at a ratio between the average bit rate and the highest bit rate, as compared with a case where copying is performed while reproducing a bit stream from a disk at a variable rate.

At this time, data is thinned out in units of pictures or picture groups from the transmitted fixed-rate bit stream, and the remaining bit streams are decoded, so that temporally skipped moving images can be continuously displayed. Play and display on monitor. This makes it possible to monitor the content of the moving image currently recorded when the recorded content of the disc encoded at the variable rate is copied at high speed to another digital recording medium.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The details of the present invention will be described below with reference to embodiments shown in the drawings.

<First Embodiment> First, a first embodiment of the present invention will be described with reference to FIGS. FIG. 1 is a block diagram of a data transmission / reception system (image data processing system) according to a first embodiment of the present invention. In FIG. 1, reference numeral 1 denotes a data transmission device; Is a data receiving device, 4 is a recording / reproducing device in the receiving device 3, and 5 is a transmission medium such as a cable for transmitting digital signals.

FIG. 2 is an explanatory diagram showing a transmission signal in the data transmission / reception system of the present embodiment, and FIG.
2 shows a transmission signal when a signal is reproduced from the digital storage medium at a variable rate by the reproduction apparatus 2 in the transmission apparatus 1. FIG. 2B shows the transmission signal fixed from the digital storage medium by the reproduction apparatus 2. This shows a transmission signal when a signal is reproduced at a rate. Here, in FIG. 2, t indicates a time interval of a picture group of a moving image, for example. Both (1) and (2) in FIG.
The hatched portions a to i indicate valid data, and the blank portion in FIG. 2A indicates invalid data.

To reproduce a bit stream at a variable rate from a digital storage medium on which a bit stream encoded at a variable rate is recorded, as shown at (1) in FIG. Then, reproduction is performed so that the head of the data boundary of the shaded portion (in this case, the data boundary of the picture group) is arranged at intervals of t on the absolute reproduction time axis. By performing the reproduction in this manner, the bit frequency of the valid data is the highest value within the range of the variable data rate, but the reproduction rate of the valid data is set at the time interval of the picture group unit of the moving image to be compressed. A variable bit stream can be reproduced.

In this case, since the actual data recorded on the digital storage medium is only the valid data in the hatched portion, the reproducing device 2 performs the reproduction while suspending or resuming the reproduction. When the bit stream reproduced in this manner is transmitted through the transmission cable 5, the receiving apparatus 3 can record the bit stream while actually decoding the bit stream and monitoring the moving image. However, in this case, a time corresponding to the reproduction time of the moving image is required.

On the other hand, when a bit stream is reproduced from a digital storage medium at a fixed rate, as shown in the case of reproducing at a fixed rate in FIG. it can. In this case, the efficiency of the time compression is a ratio between the highest rate and the average rate within the range of the variable data rate at the time of moving image encoding. Thus, high-speed copying can be performed.

<Second Embodiment> Next, a second embodiment of the present invention will be described with reference to FIG. FIG. 3 is a block diagram showing a configuration of a reproduction device in a transmission device of a data transmission / reception system (image data processing system) according to a second embodiment of the present invention. This embodiment is an application example in which an optical disk is used as a digital storage medium. As in the first embodiment, a bit stream from a digital storage medium (here, an optical disk) is converted to a variable rate or fixed rate. Either one can be reproduced.

In FIG. 3, reference numeral 11 denotes an optical disk, 12 denotes a reproduction signal processing unit from the optical disk 11, 13 denotes a variable rate reproduction control unit, 14 denotes a fixed rate reproduction control unit, 15 denotes a reproduction control selection unit, and 16 denotes a reproduction control selection unit. A signal 17 is a reproduced bit stream (here, for example, a compressed moving image signal).

The reproducing apparatus according to the present embodiment performs the variable rate control for reproducing the bit stream according to the variable rate described in the first embodiment from the optical disc 11 on which the variable rate encoded bit stream is recorded. The reproduction control unit 13 and the fixed-rate reproduction control unit 1 for controlling reproduction at a fixed rate similarly described in the first embodiment.
4, and one of the reproduction control units 13 and 14 is
The selection is performed by the reproduction control selection unit 15 according to the reproduction control selection signal 16. Then, the reproduction control unit 13 or 14 controls the reproduction method of the optical disk 11 and the processing method of the signal reproduced from the optical disk 11. As a result, the reproducing apparatus of this embodiment can reproduce a signal from the optical disk 11 at a variable rate or a fixed rate, and reproduces the signal as shown in FIG. 2 (1) or FIG. 2 (2). And can be transmitted.

<Third Embodiment> Next, a third embodiment of the present invention will be described with reference to FIG. FIG. 4 is a block diagram of a data transmission / reception system (image data processing system) according to a third embodiment of the present invention. In FIG. 4, components equivalent to those in FIG. 1 are denoted by the same reference numerals. As shown in FIG. 4, a large number (arbitrary plural) of optical disks 21 to 25 and a disk selection device 26 having an autochanger function for selecting an optical disk are provided in the transmission device 1 of the present embodiment. The disk selecting device 26 selects an optical disk based on a request signal 27 from the receiving device 3. The playback device 2 in the transmission device 1 of the present embodiment is, for example, equivalent to the playback device of FIG. 3 shown in the second embodiment.

In the configuration shown in FIG. 4, for example, specific video software is requested from the receiving device 3 by a request signal 27. Upon receiving the request signal 27, the disc selecting device 26 of the transmitting device 1 determines whether or not the requested video software is present on the optical disc currently mounted on the reproducing apparatus 2, and determines whether the video software is present on the mounted optical disc. In this case, the playback device 2 is controlled so as to perform the fixed-rate playback described in the above embodiment. If the requested video software is not present on the optical disc currently loaded in the reproducing apparatus 2, for example, an optical disc on which the requested video software is recorded is selected from the discs 21 to 25, and this is selected. It is mounted on the playback device 2 to perform fixed-rate playback. Here, the disc selecting device 26 actually has, for example, a table indicating an identification number for identifying each optical disc and its recorded content, and selects a desired optical disc based on the disc number and the recorded content. Has become.

In FIG. 4, a cable for transmitting data from the transmitting device 1 to the receiving device 3 and a cable for transmitting the request signal 27 are represented by different signal lines. By performing transmission or half-duplex transmission in a time-division manner, it can be physically realized by one cable.

As described above, according to the present embodiment, according to the request signal 27 from the receiving device 3, the transmitting device 1
A bit stream (reproduced compressed moving image signal) matching the content of the request signal 27 can be transmitted.

<Fourth Embodiment> Next, a fourth embodiment of the present invention will be described with reference to FIG. FIG. 5 is a block diagram showing a configuration of a recording / reproducing device in a receiving device of a data transmitting / receiving system (image data processing system) according to a fourth embodiment of the present invention. And signals are assigned the same numbers. In FIG. 5, 31 is a recordable optical disk, 32 is a recording signal processing unit, 33 is a fixed rate recording control unit, 34 is a recording and reproduction control selection unit, 35 is a recording and reproduction selection signal, 36 is a reproduction state signal, and 37 is a recording state The signal 38 is a bit stream to be recorded (here,
(Compressed moving image signal).

In the configuration shown in FIG. 5, when recording a bit stream transmitted from a transmission device via a transmission cable, the recording / reproduction control selection unit 34 is set to a recording state by a recording / reproduction selection signal 35. As a result, the recording / reproduction control selecting unit 34 sends the recording state signal 37 to the fixed rate recording control unit 33, and operates the recording signal processing unit 32 by the fixed rate recording control unit 33 to record the bit stream on the recordable optical disk 31. Record. At the same time,
The recording / reproduction control selection unit 34 sends a signal for prohibiting reproduction to the reproduction control selection unit 15 by the reproduction state signal 36. In response to the prohibition signal, the variable-rate reproduction control unit 13, the fixed-rate reproduction control unit 14, and the reproduction signal processing unit 12 stop operating. By such an operation, the transmitted bit stream can be recorded on the recordable optical disk 31 at a fixed rate.

When the reproduction state is selected by the recording / reproduction selection signal 35, the recording / reproduction control selection section 34
The recording is prohibited by the recording state signal 37, and the reproduction control selecting unit 15 is set to the reproduction state by the reproduction state signal.
The operation after the reproduction control selection unit 15 is the same as that described in the second embodiment with reference to FIG. Note that the recording / reproducing device of the present embodiment can be used as a recording / reproducing device in the transmitting device 1.

Here, in each of the above embodiments, an optical disk has been described as an example of the digital storage medium. However, the digital storage medium may be any other medium or a combination thereof. As a digital storage medium, a magnetic disk or a magnetic tape for a digital VTR may be used. Then, the playback device or the recording / playback device in the transmission device 1 or the recording / playback device in the reception device 3 may be configured by a device corresponding to these media types (this also applies to the following embodiments). The same is true).

<Fifth Embodiment> Next, a fifth embodiment of the present invention will be described with reference to FIGS. FIG. 6 is a block diagram of a data transmission / reception system (image data processing system) according to a fifth embodiment of the present invention. In FIG. 6, the same reference numerals are given to components equivalent to those in FIG. In FIG. 6, reference numeral 105 denotes a thinning-out reproduction device for transmission data.

FIG. 7 is an explanatory diagram showing image signal processing in the data transmission / reception system of the present embodiment. (1) of FIG. 7 represents a moving image before compression, and includes a to i.
Indicates a picture group. (2) of FIG. 7 shows a transmission signal when a signal is reproduced from a digital storage medium at a variable rate by the reproducing device 2 in the transmitting device 1. (3) of FIG. 7 shows a transmission signal when a signal is reproduced from a digital storage medium at a fixed rate by the reproduction device 2 in the transmission device 1.
Here, t in (2) of FIG. 7 indicates, for example, a time interval of a group of pictures of a moving image. Also, in (2) and (3) of FIG.
Indicates valid data obtained by performing variable rate encoding on a group of pictures with the same symbol of a moving image before compression, and a blank portion in (2) of FIG. 7 indicates invalid data. Further, (4) of FIG. 7 shows data after being decimated in picture group units by the decimating / reproducing apparatus 105, and (5) of FIG. 7 shows an image reproduced from the decimated data.

To reproduce a bit stream according to the variable rate from a digital storage medium on which a bit stream encoded at a variable rate is recorded, as shown in the case of reproducing at a variable rate in FIG. Then, reproduction is performed so that the head of the data boundary of the shaded portion (in this case, the data boundary of the picture group) is arranged at intervals of t on the absolute reproduction time axis.

By performing the reproduction in this manner, the bit frequency of the effective data is the highest value within the range of the variable data rate, but the effective data is reproduced at the time interval of the picture group of the moving image to be compressed. The bit stream can be reproduced at a variable rate. In this case, since the actual data recorded on the digital storage medium is only the valid data in the hatched portion, the reproducing device 2 performs the reproduction while temporarily stopping or resuming the reproduction. When the bit stream reproduced in this manner is transmitted through the transmission cable 5, the receiving apparatus 3 can record the bit stream while actually decoding the bit stream and monitoring the moving image. However, in this case, a time corresponding to the reproduction time of the moving image is required.

On the other hand, when a bit stream is reproduced from a digital storage medium at a fixed rate, as shown in FIG. 7 (3) when reproduced at a fixed rate, invalid data portions may be temporally padded. it can. In this case, the efficiency of the time compression is a ratio between the highest rate and the average rate within the range of the variable data rate at the time of moving image encoding. Thus, high-speed copying can be performed.

Data corresponding to the picture groups c, f, g, and i are thinned out from the fixed-rate signal as shown in FIG. The remaining a, b, d,
When a picture group is reproduced from the data of e and h, FIG.
As shown in (5), the rate of the picture group matches the rate of the picture group of the moving image before compression. Therefore, by displaying this on a monitor, the moving image currently being recorded can be monitored while copying at a high speed.

<Sixth Embodiment> Next, a sixth embodiment of the present invention will be described with reference to FIGS. FIG. 8 is a block diagram showing a configuration of a reproduction system in a receiving device of a data transmission / reception system (image data processing system) according to a sixth embodiment of the present invention. In FIG. 8, reference numeral 111 denotes a reproduction system of the receiving apparatus 3;
Side, a received signal receiving unit 113, a data thinning-out determination unit 113, a picture group unit, a memory 114, a compressed image decoder 115, a monitor 116, a reference signal 117 indicating a picture group interval, and 118 to the memory 114 Is a write stop signal.

FIG. 9 is an explanatory diagram showing signal processing in the reproduction system 111 in the receiving device of the data transmission / reception system of this embodiment. 9 (1) is a reference signal 117, FIG. 9 (2) is a received signal 112, FIG. 9 (3) is a signal indicating the head of a group of pictures a to i in the received signal 112, and FIG.
(4) shows data to be written into the memory 114 after the data is decimated, and (5) in FIG. 9 shows a reproduced image decoded from the data after the data is decimated.

The thinning-out judging section 113 of this embodiment detects the head of each picture group from the received signal 112. The values ta to ti shown in (3) of FIG.
Is the head signal of each of the picture groups a to i detected. The thinning determination unit 113 determines a group of pictures to be thinned based on the reference signal 117 (t0 to t5) input from the compressed image decoder 115. In the present embodiment, the presence of ta between the reference signals t0 and t1 is detected, and the data of the picture group a is written into the memory 114. Next t1 and t
Between the two, tb which appears first is detected, and only the picture group b is written into the memory 114, and the picture group c is not written into the memory 114.

As described above, the head of the picture group that appears first in each cycle of the reference signal is detected, and only the one picture group whose head is detected is written in the memory 114. That is, at each time interval t of the picture group, only one picture group is selected and written to the memory 114, and the picture group is selected without writing the data of the remaining picture group to the memory 114.

By sequentially decoding the data written in the memory 114 as described above,
The thinned decoded image can be reproduced. As a result, the moving image currently being recorded can be monitored while copying at a high speed.

<Seventh Embodiment> Next, a seventh embodiment of the present invention will be described with reference to FIGS. FIG. 10 is a block diagram showing a configuration of a reproduction system in a receiving device of a data transmission / reception system (image data processing system) according to a seventh embodiment of the present invention. Signals are given the same numbers. In FIG.
119 is a write inhibit signal for preventing the memory 114 from overflowing.

FIG. 11 is an explanatory diagram showing signal processing in the reproduction system 111 in the receiving device of the data transmission / reception system of this embodiment. (1) of FIG.
2, (2) in FIG. 11 is a signal indicating the head of the picture group in the received signal 112, (3) in FIG. 11 is a write inhibit signal 119 in the memory 114, and (4) in FIG. And (5) in FIG. 11 represent the reproduced image decoded from the data after data thinning,
Each is shown.

Also in this embodiment, the thinning-out judging section 113
Then, the head of each picture group is detected from the received signal 112. In this embodiment, when the amount of data remaining in the memory 114 increases, the memory 114 outputs a write inhibit signal 119 to prevent overflow. When the write prohibition signal 119 indicates the prohibition state, the thinning determination unit 113 stops writing the data of the picture group indicated by the head signal of the picture group detected in the prohibition section to the memory 114 by the write stop signal 118.

As a result, in this embodiment, FIG.
As shown in (3), control is performed so that the data of the picture groups c, f, g, and i are not written to the memory 114. Therefore, the data written to the memory 114 is the data shown in FIG.
As shown in 1 (4), by decoding this with the compressed image decoder 115, the thinned decoded image can be reproduced. Thus, the moving image currently being recorded can be monitored while copying at a high speed.

<Eighth Embodiment> Next, an eighth embodiment of the present invention will be described with reference to FIG. FIG. 12 is an explanatory diagram showing processing of an image signal in a data transmission / reception system (image data processing system) according to the eighth embodiment of the present invention, and (1) to (3) of FIG. It is equivalent to (1) to (3) in FIG. 7 of the example, and (4) in FIG.
Shows a reproduction method by the reproduction system of the receiving apparatus of the present embodiment, and shows an image reproduced from the thinned data.

In this embodiment, data of the number of screens proportional to the transmission time of the data of each of the picture groups a to i is extracted from the transmission signal (3) in FIG. Extracted from a group of pictures, played back, and displayed.

As a result, an image of at least one screen can be reproduced from each picture group, and a monitor with less discomfort can be performed as compared with a case where data is thinned out and reproduced in picture group units.

<Ninth Embodiment> Finally, a ninth embodiment of the present invention will be described with reference to FIG. FIG. 13 shows a ninth embodiment of the present invention.
FIG. 2 is an explanatory diagram illustrating signal processing in a reproduction system in a receiving device of the data transmission / reception system (image data processing system) according to the embodiment. FIG. 13A shows a received signal, and FIG. 13B shows a signal indicating the head of a picture group in the received signal. FIG. 13C shows a method of determining the number of display screens, and tp is a display interval of each screen. FIG. 13D shows a display screen after decoding.

In this embodiment, in order to determine the number of display screens for each picture group, the number of display interval signals (tp) of each screen existing between the head signals of each picture group is counted. The number is determined as the number of display screens, and screen data for that number is extracted from each picture group and displayed.

Thus, from the transmission signal reproduced at a fixed rate, data of the number of screens proportional to the transmission time of the data of each picture group can be extracted from each picture group, reproduced, and displayed. it can.

[0048]

According to the present invention as described above, according to the present invention, a digital storage medium such as an optical disk, while a copy fast, it is possible to monitor the contents of the moving image that is currently recorded.

[Brief description of the drawings]

FIG. 1 is a block diagram of a data transmission / reception system according to a first embodiment of the present invention.

FIG. 2 is an explanatory diagram showing transmission signals in the data transmission / reception system according to the first embodiment of the present invention.

FIG. 3 is a block diagram showing a configuration of a playback device in a transmission device of a data transmission / reception system according to a second embodiment of the present invention.

FIG. 4 is a block diagram of a data transmission / reception system according to a third embodiment of the present invention.

FIG. 5 is a block diagram showing a configuration of a recording / reproducing device in a receiving device of a data transmitting / receiving system according to a fourth embodiment of the present invention.

FIG. 6 is a block diagram of a data transmission / reception system according to a fifth embodiment of the present invention.

FIG. 7 is an explanatory diagram showing image signal processing in a data transmission / reception system according to a fifth embodiment of the present invention.

FIG. 8 is a block diagram showing a configuration of a reproduction system in a receiving device of a data transmission / reception system according to a sixth embodiment of the present invention.

FIG. 9 is an explanatory diagram showing signal processing in a reproduction system in a receiving device of a data transmission / reception system according to a sixth embodiment of the present invention.

FIG. 10 is a block diagram illustrating a configuration of a reproduction system in a receiving device of a data transmission / reception system according to a seventh embodiment of the present invention.

FIG. 11 is an explanatory diagram showing signal processing in a reproduction system in a receiving device of a data transmission / reception system according to a seventh embodiment of the present invention.

FIG. 12 is an explanatory diagram showing image signal processing in a data transmission / reception system according to an eighth embodiment of the present invention.

FIG. 13 is an explanatory diagram showing signal processing in a reproduction system in a reception device of a data transmission / reception system according to a ninth embodiment of the present invention.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 transmitting device 2 reproducing device 3 receiving device 4 recording / reproducing device 5 transmission cable (transmission medium) 11 optical disk 12 reproduction signal processing unit 13 variable rate reproduction control unit 14 fixed rate reproduction control unit 15 reproduction control selection unit 16 reproduction control selection signal 17 Reproduced bit stream (compressed moving image signal) 21 to 25 Optical disk 26 Disk selection device 27 Request signal 31 Recordable optical disk 32 Recording signal processing unit 33 Fixed rate recording control unit 34 Recording / reproduction control selection unit 35 Recording / reproduction selection signal 36 Reproduction Status signal 37 Recording status signal 38 Bit stream to be recorded (compressed moving image signal) 105 Thinning-out reproduction device 111 Reproduction system of receiving device 112 Received signal 113 Thinning-out determination unit 114 Memory 115 Compressed image decoder 116 Monitor 117 Reference signal 118 Writing Stop signal 119 write inhibit signal

──────────────────────────────────────────────────続 き Continuation of the front page (72) Inventor Takao Arai 292 Yoshida-cho, Totsuka-ku, Yokohama-shi, Kanagawa Pref. Hei 5-35407 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) H04N 5/76-5/956 G11B 20/10-20/12 H04N ^7/ 14-7/173

Claims (4)

(57) [Claims] A plurality of picture groups having different compression ratios are recorded.
From the digital storage media
Read the composed moving image data, and
When recording to a digital storage medium,
In a moving image monitoring method for monitoring data, a moving image obtained by thinning out a part of the moving image data is monitored.
A moving picture monitoring method characterized by the above-mentioned. 2. The moving picture monitoring method according to claim 1,
There are, in the moving image obtained by thinning out a part of the moving image data, picture relevant
It is characterized in that it is a moving image thinned out per unit
Video monitoring method. 3. The moving picture monitoring method according to claim 1,
There are, in the moving image obtained by thinning out a part of the moving image data, picture relevant
Video characterized in that the video is
Image monitoring method. 4. The moving picture monitoring method according to claim 1,
There are, said moving image obtained by thinning out a part of the moving image data, each Pic
Decimation to leave at least one screen image per char group
A moving image monitoring method, characterized in that the moving image is a moving image.