JP2003018547A - Video stream transmitting method, scene change point detecting method and decode instruction displaying apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To solve the problem that, when a video picture is to be displayed in a direction opposite to a normal time base, a re-encoder (decoder or storage device in a reverse direction) must be equipped in the case of a video stream utilizing video coding having correlation in the direction of the time base. SOLUTION: The time base in a video stream is changed with respect to a change in the time base by a slow motion. In the ISO/IEC13818-1 standards, the output intervals between PTS, DTS and packets in a PES header are changed. Further, a so-called non-display picture, which decodes a video stream and does not display it, is transmitted to apply decoding processing to a screen. A non-display instruction signal indicating the non-display picture is superimposed on the non-display picture.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image stream in the case of displaying an image stream using image coding having correlation in the time axis direction such as MPEG-2 on a time axis different from the normal time axis. The present invention relates to a transmission method and device, and further to a method and device for detecting a switching point of an image scene.

[0002]

2. Description of the Related Art Image coding with correlation in the time axis direction, for example, ISO / IEC13818-2, that is, M
As a method of displaying an image stream using PEG-2 on a time axis different from the normal time axis, there is one described in Japanese Patent Laid-Open No. 08-223533. The outline will be described below.

An object of the invention described in Japanese Patent Laid-Open No. 08-223533 is to provide a disc player that smoothes the movement of a display screen during slow motion reproduction of disc recording information. Image data encoded by MPEG-2 is recorded on the disc.
Intra frame (I picture), Forward predictive picture (P picture), Bidirectional picture (B picture)
Then, the image is composed. Usually, slow motion image data is not recorded. The P and B pictures have been subjected to predictive coding from a temporally past picture or a temporally future picture, and have a motion vector. Here, for example, 1 / n
(N is a natural number) In the case of slow motion playback, this motion vector is incremented by (1 / n) × I (I is incremented for each display screen. In the case of NTSC, up to 30 PAL
In the case of up to 25), a new interpolation motion vector is generated. Then, using this interpolated motion vector, an interpolated picture is generated. A slow motion screen is generated using this interpolation picture.

However, generating an interpolation picture means mounting an encoding device. MP
EG encoders are generally expensive and it is not preferred to have an encoder onboard. Especially High Def
In the case of "init", the price of the encoding device is very expensive and it is difficult to mount it. Moreover, re-encoding deteriorates the image quality. Furthermore, in the case of reverse slow motion, it is not possible to generate a display image only by generating an interpolated picture using only the interpolated motion vector. This is because in the case of reverse slow motion, the referenced image is transmitted after the image to be displayed. Therefore, in order to realize the reverse slow motion, two or more units of Group of Pictures are stored in the storage device, from which they are completely decoded and re-encoded to further generate an interpolated picture. Must. To achieve this, the device becomes very complicated.

As described above, in the invention disclosed in Japanese Patent Laid-Open No. 08-223533, which is a conventional example, a re-encoding device is used.
There is a big problem that it is impossible to develop a popular type device (in the case of the reverse direction, a decoding device and a large-capacity storage device) must be mounted.

On the other hand, as a means for detecting a scene change, a position where the scene changes is stored in a specific area and information from the specific area is used. However, in order to store the position where the scene changes in the specific area, it is necessary to reproduce the image once and detect the position by the person, not the machine. That is,
There was a big problem that scene detection could not be automated.

In view of the above problems, the present invention provides a method for transmitting an image stream capable of realizing slow motion and reverse slow motion with a simple device. Furthermore, the present invention provides a switching point detection method capable of detecting a scene switching point with a simple device.

[0008]

In order to achieve the above object, the image stream transmission method according to the present invention changes the time axis in the image stream in response to the change of the time axis due to slow motion. ISO / IEC13818-1
In the case of the standard, PTS and DTS in the PES header are changed. Further, in the case of reverse slow motion, information indicating that the image stream is decoded but not displayed is added. In the case of the ISO / IEC13818-1 standard, Stream_id in the PES header or P
ES # Private_data or PES_ex
Use the tension_field. In addition, ISO /
User_dat in the case of the IEC13818-2 standard
a or temporal in the Picture header
_Reference or extra_info
mation_Picture is used. Then, as a means for detecting the change of the scene, the amount of data at the time of encoding using prediction in the time axis direction is used. Further, in the case of the ISO / IEC13818-1 standard, S
It can also be used when the value of the quantization table in the expression_Header changes.

With the above-mentioned structure, a smooth slow video can be viewed even in the case of an image stream utilizing image coding with correlation in the time axis direction. Further, the switching points of the scenes can be automatically set, and it is not necessary to view all the scenes and set the switching points.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION The image stream transmission method according to claim 1 of the present invention performs the decoding process of the image coding of the image stream using the image coding with correlation in the time axis direction, but after decoding. The non-display instruction signal indicating that the image data of 1 is not displayed on the screen is retained in the image stream. An advantage of the image stream transmission method according to the first aspect of the present invention is that, when it is desired to display the image by reversing the time axis, the images are displayed in the time direction in a consistent order. According to the image stream transmission method of claim 2 of the present invention, when the order change screen having a different screen display order from the decoding order of the image encoding of claim 1 is held, the non-display instruction signal of claim 1 is transmitted. It is characterized in that it is held in the order change screen. The effect of the image stream transmission method according to claim 2 of the present invention is that the images are displayed in a consistent order in the time direction. In the image stream transmission method according to claim 3 of the present invention, when the screen is updated in the forward direction and the order-changed screen according to claim 2 is present, a picture is encoded other than bidirectional prediction in the time axis direction. The non-display instruction signal according to claim 1 is held in a part or all of the above. The effect of the image stream transmission method according to the third aspect of the present invention is that when the screen is updated in the forward direction, the images are displayed in a consistent order as the time direction. A decoding display device according to a fourth aspect of the present invention is the decoding display device according to the first to third aspects.
Decoding of image coding is performed on the picture that holds the non-display instruction signal, but the screen is not displayed, and decoding of image coding is performed on the picture that does not hold the non-display instruction signal. The feature is that processing is performed and the screen is displayed. An effect of the decoding and displaying apparatus according to claim 4 of the present invention is to provide a decoding and displaying device capable of complying with claims 1 and 2. The image stream transmission method according to claim 5 of the present invention is ISO / IEC13.
The non-display instruction signal according to claim 1, which is an image stream using an encoding method standardized in 818, is ISO
The feature is that the existing value of / IEC13818 is changed and used. The effect of the image stream transmission method of claim 5 according to the present invention is that it can comply with ISO / IEC13818 without increasing the data amount. The image stream transmission method according to claim 6 of the present invention is an image stream using an encoding method standardized by ISO / IEC13818, and the non-display instruction signal according to claim 1 is a spare area of ISO / IEC13818. Is added to the image stream for use. The effect of the image stream transmission method of claim 6 according to the present invention is the same as the conventional ISO / IEC1381.
ISO / IEC13 without adversely affecting compatible devices
818 can be supported. Claim 7 according to the present invention
Image stream transmission method of ISO / IEC1381
An image stream using an encoding method standardized by the standard No. 8 as the non-display instruction signal according to claim 1.
It is characterized in that the meaning of the existing signal of EC13818 is changed and used. The effect of the image stream transmission method of claim 7 according to the present invention is that it can comply with ISO / IEC13818 without increasing the data amount. According to the image stream transmission method of claim 8 of the present invention, a reproduction other than the normal reproduction is performed on the image stream from the storage device that records the image stream using the image encoding having the correlation in the time axis direction. In this case, the picture to be displayed is thinned according to the transmission capacity of the communication path or the decoder capacity for decoding the image coding. The effect of the image stream transmission method of claim 8 according to the present invention is that the image stream does not overflow on the communication path or in the decoding device. The image stream transmission method of claim 9 according to the present invention is an image stream that uses image coding with correlation in the time axis direction, and in order to perform screen display by reversing the screen update order, It is characterized in that only the stream necessary for decoding the image coding is retransmitted. The effect of the image stream transmission method according to claim 9 of the present invention is that the screen display can be performed by reversing the screen update order. The image stream transmission method according to claim 10 of the present invention is an image stream that uses image encoding having correlation in the time axis direction, wherein the image stream is subjected to image encoding decoding processing, but after decoding Of a decoding device capable of responding to a non-display instruction signal indicating that the image data is not displayed on the screen or a decoding device incapable of responding to the non-display instruction signal. A non-display instruction signal is held in the image stream to transmit the image stream, and if the decoding device is not compatible, the non-display instruction signal is not held in the image stream and a correlation in the time axis direction is obtained. It is characterized by transmitting a picture-only image stream that has not been encoded. The effect of the image stream transmission method of claim 10 according to the present invention is that not only the effect of claim 1 but also an optimum image stream for a compatible device can be output. The image stream transmission method according to claim 11 of the present invention is an image stream that uses image coding with correlation in the time axis direction and has no correlation in the time axis direction for decoding and displaying on the screen. The feature is that an error flag is set to a picture other than the picture that has been converted and output. The effect of the image stream transmission method according to claim 11 of the present invention is that a part of the screen can be decoded and displayed in the conventional device without adversely affecting the conventional device. An image stream transmitting method according to a twelfth aspect of the present invention is an image stream using an encoding method standardized by ISO / IEC13818-1,
Error flag of ISO / IEC13818-1
Transport_error_indicato
It is characterized by using r. Claim 1 according to the present invention
The effect of the second image stream transmission method is ISO /
It is possible to comply with IEC13818-1 and to decode and display a part of the screen even in the conventional device without adversely affecting the conventional device. According to a thirteenth aspect of the present invention, there is provided the reproducing apparatus according to ISO / IEC1381.
An image stream using the encoding method standardized in 8-1 is recorded, and when the recorded image stream is reproduced and the display time of the screen is changed and displayed, time management is performed. It is characterized in that the time management signal being performed is rewritten to a predetermined value and the image data stream is output to the decoding device. An advantage of the reproducing apparatus according to claim 13 of the present invention is that the display speed of the screen can be easily changed with a simple device. According to a fourteenth aspect of the present invention, in the playback apparatus of claim 14, the screen is updated in the forward direction by 1 / n (n
Is a natural number) in the case of slow display, claim 1
PTS and DTS are selected as the time management signal described in 3, and the difference value for each picture of PTS and DTS is (1 / f) × n seconds (f is 30 for NTSC and 25 for PAL). It is characterized by rewriting PTS and DTS. An advantage of the fourteenth aspect of the reproducing apparatus according to the present invention is that screen display at even intervals can be performed by a simple method. According to a fifteenth aspect of the present invention, in the reproducing apparatus according to the thirteenth aspect, as the time management signal, Sequ
sense Header frame_rate_co
It is characterized by selecting de. An advantage of the fifteenth aspect of the reproducing apparatus according to the present invention is that the image processing of the decoding display apparatus can be easily controlled. A reproducing apparatus according to a sixteenth aspect of the present invention is a reproduced image data stream from the reproducing apparatus according to the thirteenth to fifteenth aspects, and displays the screen update in a forward direction in a slow display of 1 / n (n: natural number). In this case, not only is PTS and DTS rewritten so that the difference value for each picture of PTS and DTS is (1/30) × n seconds, but also Transport
The output interval of t Packet is also characterized by being n times as large as that during normal reproduction. The effect of the sixteenth aspect of the present invention in the reproducing apparatus is to facilitate the control of the image processing of the decoding display apparatus, particularly the control of the video buffer. According to a seventeenth aspect of the present invention, there is provided a scene switching point detecting method, which is an image stream using image coding having a correlation in a time axis direction, wherein a point at which information in the image stream greatly changes is recorded. The feature is that it is determined to be switched. An effect of the scene switching point detecting method of claim 17 according to the present invention is that the scene switching point can be automatically detected. Claim 18 according to the present invention
The method for detecting a scene switching point is characterized in that the point where the information described in claim 17 changes greatly is the point where the image data amount of the same encoding means changes greatly. An advantage of the method for detecting a scene switching point according to claim 18 of the present invention is that the scene switching point can be automatically detected even in an image stream in which a plurality of encoding methods are mixed. A scene switching point detection method according to a nineteenth aspect of the present invention is an image data stream using an encoding method standardized by ISO / IEC13818-2, wherein the information according to the seventeenth aspect is greatly changed. ,
It is characterized in that the value of the quantization table in Sequence_Header is changed. The effect of the scene switching point detection method of claim 18 according to the present invention is that it can be easily realized in encoding using the standardization of ISO / IEC13818-2.

The recording / reproducing apparatus according to a twentieth aspect of the present invention is characterized in that the scene switching points are registered and recorded as indexes, and the scene switching points are used as an index search during reproduction.

The effect of the recording / reproducing apparatus according to claim 20 of the present invention is that an index can be automatically created.

Embodiments of an image stream transmitting method, a decoding display device, a reproducing device, a scene switching point detecting method, and a recording / reproducing device according to the present invention will be described below in detail with reference to the drawings.

(First Embodiment) FIG. 1 is a stream configuration diagram showing a configuration of an image stream in an image stream transmission method according to the present invention. FIG. 2 shows an example of an encoding method in which a correlation is given in the time axis direction. FIG. 3 is a decoding display device for receiving, decoding and displaying an image stream. In order to simplify the explanation, here, an image stream that uses image coding with correlation in the time axis direction is recorded in a storage device, and the image stream to be transmitted is generated by reproducing the image stream. I will do it. Also, with the screen update order set to the forward direction, the case where the image stream of the special reproduction image that outputs a part of the recorded screen is transmitted and the case where the screen update order is reversed and the image stream is transmitted The case and the case will be described.

In FIG. 1, 1 is an n-th video stream (n is an integer), 2 is a c-th audio stream (c
Is an integer), 3 is an m-th video stream (m is an integer),
4 is the d-th audio stream (d is an integer), 10
Is the (i-1) th picture, 11 is the (i) th picture, 12 is the (i + 1) th picture, and 13 is (i +
2) The picture, 14 is the (j-1) th picture, (i and j are integers), 20 is the header, and 21 is the payload (valid data area).

In FIG. 2, reference numeral 31 is a 0th picture, which is a picture (I picture) which is coded by a coding method which performs coding without using prediction in the time axis direction, and 32 is the first picture. It is a picture, and by the coding method that performs coding using bidirectional prediction on the time axis,
A picture (B picture) 33 for coding is a second picture, and a picture (B picture) 34 for coding by a coding method for coding using bidirectional prediction on the time axis. Is a third picture, and a picture (P picture) that performs coding by a coding method that performs coding using prediction from the forward direction of the time axis, and similarly from 35 to 45, in each picture. is there.

In FIG. 3, 120 is an input stream analysis circuit, 121 is a decoding circuit, 122 is a control signal generation circuit, 123 is a display circuit, 124 is a display device, 125 is an image data transmission path, and 126 is a display stop signal transmission path. Is.

The operation of the embodiment of the present invention will be described with reference to FIGS. 1, 2, and 3. The audio processing is omitted since it is not directly related to the present invention.

Now, let us consider the streams from the n-th video stream 1 to the m-th video stream 3 among the streams transmitted in series. The m-th video stream includes the (i-1) th picture 10 to the (j-1) th picture 14. The structure of the picture data is a header 20 and a payload 21. The (i-1) th picture 10 is encoded by an encoding method that does not perform prediction in the time axis direction. The i-th picture 11 and the (i + 1) th picture 12 are coded by a bidirectional prediction method from two pictures of the (i-1) th picture 10 and the (i + 2) th picture 13. (I + 2)
The thirteenth picture 13 is coded by a coding method for performing prediction from the (i-1) th picture 10. This will be described in comparison with FIG. (I-1) th picture 10
Is the I picture of the picture 31 in FIG. i-th picture 11 and (i + 1) -th picture 12
Are the B pictures of the picture 32 and the picture 33 of FIG. 2, respectively. The (i + 2) th picture 13 is the P picture of the picture 34 of FIG.

First, a case will be described in which the screen update order is set to the forward direction and the image stream of the special reproduction image for outputting a part of the recorded screen is transmitted.

The transmission order of image streams in the forward direction is
As shown at the time of forward transmission in FIG. 1, the (i−1) th picture 10, the (i + 2) th picture 13, the ith picture 11, and the (i + 1) th picture 12 are shown. Each picture transmitted in this order is subjected to a decoding process. And the decrypted screen is
The pictures are displayed in the same order as they were encoded, with the order changed. That is, the (i-1) th picture 1
The order is 0, i-th picture 11, (i + 1) -th picture 12, and (i + 2) -th picture 13.

For the sake of simplicity, here, the decoding processing is performed for the pictures other than the B picture, but the image is not displayed on the screen. Generally, of the I picture, the P picture, and the B picture, the B picture has the largest number of screens. Therefore, in the case of special reproduction in which a part of the screen is output in the forward direction, by doing so, a picture with a large number of screens is selected and displayed, so that the temporal relationship becomes relatively easy to understand. In particular,
This is valid when using the DSM trick mode of the ISO / IEC13818-1 standard. This is because when using the DSM trick mode of the ISO / IEC13818-1 standard, the recommended operation of the decoding display device in the standard is to immediately decode and display the received image stream. Therefore, if the decoding display device performs the operation based on the recommended operation, all the pictures (I, P, B) will be displayed immediately after decoding, and an inconsistent image on the time axis will be displayed on the screen. Will be done. In the present invention, if a non-display instruction signal (a signal indicating that decoding is performed but not displaying) is added to a picture other than the B picture, DS of the ISO / IEC13818-1 standard is added.
Even if the M-trick mode is used, it is possible to display a screen that has no temporal contradiction. A non-display instruction signal is added to the (i-1) th picture 10 and the (i + 2) th picture 13, and a non-display instruction signal is added to the (i + 1) th picture 12 and the (i + 2) th picture 13. do not do. That is, I picture and P
The non-display instruction signal is added only to the picture. By doing so, it is possible to construct a screen that is temporally consistent with only the B picture.

Next, a case where the order of updating the screens is reversed will be described.

The transmission order in the reverse direction is the same as that shown in the reverse transmission in FIG. i-th picture 11, (i
Since the (i-1) th picture 10 and the (i + 2) th picture 13 are required to decode and display the +1) th picture 12, the (i-1) th picture 10 and the (i + 2) th picture are required. 13 data i
Th picture 11 and (i + 1) th picture 12
Must be sent before. However, the display order is different from the decoding order. Therefore, on the receiving side,
It is necessary to perform a decoding process on the (i-1) th picture 10 and the (i + 2) th picture 13 to generate a reference screen for decoding the ith picture 11 and the (i + 1) th picture 12. . Furthermore, the receiving side needs a procedure of not displaying the (i-1) th picture 10. This is because the (i−1) th picture 10 is a picture that is earlier in time than the ith picture 11 and the (i + 1) th picture 12.
Th picture 11 and (i + 1) th picture 12
This is because it should not be displayed earlier.

Therefore, although a decoding process is performed in the header 20 of the (i-1) th picture 10, a flag is set on the screen to indicate that it is not displayed. Then, on the receiving side, the decoding process of the (i-1) th picture 10 and the (i + 2) th picture 13 is performed, and the reference screen for decoding the ith picture 11 and the (i + 1) th picture 12 is generated. Then, only the (i + 2) th picture 13 is displayed on the screen. Subsequently, the (i + 1) th picture 12 and the ith picture 11 are decoded and displayed on the screen.

The processing on the receiving side will be described with reference to the block diagram of the decoding and displaying apparatus shown in FIG.

The image stream is input to the input stream analysis circuit 120. The input stream analysis circuit 120 detects a non-display instruction signal indicating that the decoded image data is not displayed on the screen although the decoding process of the image coding is performed, and outputs it to the control signal generation circuit 122 via the transmission line 126. To do. At the same time, the image data is output to the decoding circuit 121 via the transmission path 125. The decoding circuit 121 performs a decoding process on the input stream and sets it as a reference screen. In the control signal generation circuit 122, the decoding circuit 121 generates an instruction signal indicating whether or not to display the decoded screen data, based on the input non-display instruction signal, and outputs the instruction signal to the decoding circuit 121. In the decoding circuit 121, in response to an instruction signal from the control signal generation circuit 122, screen data is output to the display circuit 123 if it is a screen to be displayed, and if it is a screen that should not be displayed, it is stopped as a reference screen. Keep it. The display circuit 123 outputs the input screen data to the display device 124. Furthermore, on the sending side, during the preparatory stage before transmitting the image stream,
It is detected whether the connected decoder is a model that supports the non-display instruction signal of the present invention or a model that does not support it. If the connected decoder is a model compatible with the non-display instruction signal of the present invention, the non-display instruction signal of the present invention is added to start transmission. If the connected decoder is a model that does not support the non-display instruction signal of the present invention, the picture is encoded without correlation in the time axis direction without adding the non-display instruction signal of the present invention. Only transmit the image stream.

As described above, when the update order of the screens is set to the forward direction and the image stream of the special reproduction image that outputs a part of the recorded screens is transmitted and when the time axis is to be displayed in reverse, , It is possible to display in the time direction in a consistent order. Moreover, as a preparatory step before the transmitting side transmits the image stream, it is performed to detect whether the connected decoder is a model that supports the non-display instruction signal of the present invention or a model that does not support it. For example, it will be possible to support conventional models.

(Second Embodiment) An image stream transmission method according to the second embodiment of the present invention will be described.
FIG. 4 is a stream configuration diagram showing the image stream configuration at the time of backward transmission in the image stream transmission method according to the present invention, taking ISO / IEC13818-1 of MPEG2 as an example. An image stream transmission method according to the second embodiment will be described with reference to FIG. The difference between the second embodiment and the first embodiment is that the MPEG2 is used as the image coding having the correlation in the time axis direction, and the decoding process is performed but the decoded image data is not displayed. Reserved as a command signal in the PES header
Stream_of PES indicating data Stream
Using id or Private Data
To use a field or extension field. In addition, as a non-display instruction signal, Tra
It is to give hidden meaning to the nport_priority.

In FIG. 4, 1 is an nth video stream (n is an integer), 2 is a cth audio stream (c
Is an integer), 3 is an m-th video stream (m is an integer),
4 is the d-th audio stream (d is an integer), 10
Is the (i-1) th picture (I picture), 11 is the (i) th picture (B picture), and 12 is (i +
1) th picture (B picture), 13 (i +
2) th picture (P picture), 14 is (j-
1) th picture, (i, j are integers), 49 is PES
Header, 21 is payload, 50 is Packet St
art Code, 51 is Stream ID, 52 is P
ES Packet Length, 53 is the binary number "1"
0 ", 54 is Control Signals, 55 is Flags, 56 is PTS / DTS, 57 is ESCR,
58 is ES Rate, 59 is DSM Trick Mo
de, 60 is Additional Copy Inf
o. , 61 is PES CRC, 62 is PES extend
sion, 63 is Flags, 64 is PES Priv
ate data, 65 is others, 66 is PES
_Extension_field_length, 6
Reference numeral 7 is a PES_extension_field.
The structure of the PES header is Control Signal
s54, Flags55, Flags63, etc. are described briefly. For details, refer to ISO / IEC13818-1, which is the MPEG2 standard. The I picture, the B picture, and the P picture are the same as those in the first embodiment. PE as a non-display instruction signal
The value of Stream ID in the S header is used. Stre
The am ID is an 8-bit signal. Normally, in the StreamID of the image stream, the upper 4 bits are “111”.
1 "(binary number), the lower 4 bits are arbitrary.
S that indicates the Reserve data Stream
The streamID is a value from “1111 1010” (binary number) to “1111 1110” (binary number). Select one of these values. For example, "1111 10
10 "(binary number) is selected as a signal indicating that the image decoding process is performed but the decoded image data is not displayed. At the time of backward transmission, the (i-1) th picture 10 and the (i + 2) th picture are selected. The decoding process is performed on the picture 13. However, the (i-1) th picture 10 does not display the screen, so the Stream ID 51 of the (i-1) th picture 10 is rewritten to "1111 1010". , (I + 2) th picture 13 and (i +
1) St of the 12th picture 12 and the i-th picture 11
The ream ID51 is not changed.

Then, the image stream as described above is
When the decoding display device of FIG. 3 described in the first embodiment receives it, it is possible to display a screen that is consistent on the time axis. That is, the (i + 2) th picture 13, (i +
1) The 12th picture 12 and the i-th picture 11 can be sequentially output. In this case, in the input stream analysis circuit 120 in FIG. 3, the PES header 49
The Stream ID 51 value of the
And output to the control signal generation circuit 122. In this embodiment, as the non-display instruction signal, in the StreamID of the PES header, the Reserved dare is set.
The value of ta Stream was used, but Private_
"1011 110", which is a value indicating stream_1
1 "(binary) and Private_stream_
It goes without saying that "1011 1111" (binary number), which is a value indicating 2, may be used. Furthermore, the non-display instruction signal is sent to the PES_Privat in the PES_Header.
e_data64 or PES_extension
It is also possible to insert it inside the field of n_field 67. This is Private_stream
m_1 and Private_stream_2 are already valid for the stream being used. further,
In the MPEG2 standard, Reserved bits may be used as a non-display instruction signal. in this case,
The decoder side is notified in advance which bit is used.

Further, the Transport Packet
Transport_priorit in Header
A non-display instruction signal can be obtained by changing the meaning of y. That is, transport_pr
iority = "0" is set as a non-display instruction, and the transp
ort_priority = “1” display instruction. As described above, when it is desired to reverse the time axis for display, the time direction can be displayed in a consistent order.

(Embodiment 3) An image stream transmission method according to Embodiment 3 of the present invention will be described.
FIG. 5 is a stream configuration diagram showing the image stream configuration at the time of backward transmission in the image stream transmission method according to the present invention, taking ISO / IEC13818-2 of MPEG2 as an example. An image stream transmission method according to the third embodiment will be described with reference to FIG. The difference between the third embodiment and the first and second embodiments is that MPEG2 is used as the image coding with correlation in the time axis direction, the decoding process is performed, but the decoded image data is not displayed. As a non-display instruction signal indicating that, User data
Or the Tempor of Picture_Header
al_reference or extra_in
formation_Picture is used.

In FIG. 5, 1 is an n-th video stream (n is an integer), 2 is a c-th audio stream (c
Is an integer), 3 is an m-th video stream (m is an integer),
4 is the d-th audio stream (d is an integer), 10
Is the (i-1) th picture (I picture), 11 is the (i) th picture (B picture), and 12 is (i +
1) th picture (B picture), 13 (i +
2) th picture (P picture), 14 is (j-
1) th picture, (i, j are integers), 49 is PES
Header, 21 is payload, 70 is Sequence
Header, 71 is User Data, 72 is GO
P Header, 73 is User Data, 74 is P
picture Header, 75 is Picture S
start code, 76 is Temporal Ref
Rence, 77 is a Picture Type, 78 is a VBV Delay, 79 is a Vector or Cod
es and 80 are extra_bit_Picture, 8
1 is extra_information_Pictu
Re and 82 are extension headers. Here, Vector or Codes 79 is described in a simplified format. Also, extension
Headers 82 are also described in a simplified format.
For details of the structure of the stream, refer to ISO / IEC13818-1, which is the MPEG2 standard.
The non-display instruction signal is set in the field of User Data 71 or the field of User Data 73. This is because the fields of User Data can be set in either of them. For example, Use
If 8 bits at the byte position next to the start code of r Data is "01" (hexadecimal number), decoding is performed as usual to display the screen, and if "02" (hexadecimal number), Decrypt but do not display the screen.
Since the (i-1) th picture 10 performs decoding but does not display the screen, "02" (hexadecimal number) is set. And
The (i) -th picture 11, the (i + 1) -th picture 12 and the (i + 2) -th picture 13 perform decoding as usual and display the screen, so "01" (hexadecimal number) is set.

The image stream thus configured is transmitted to the receiving side. If the decoding display device on the receiving side has the configuration shown in FIG. 3, the displayed screen is consistent on the time axis. However, in the input stream analysis circuit 120 in FIG. 3, the non-display instruction signal is detected by the User Data 71 or the User Data.
The above value of the field of 73 shall be used. In addition,
It goes without saying that the non-display instruction signal does not have to be “02” (hexadecimal number) and may have other values. Further, it goes without saying that the non-display instruction signal does not have to be 8 bits and may have another number of bits. Further, the non-display instruction signal is transmitted to extra_information_Pict in the Picture Header 74.
It may be set in the field of ure81. In this case, it may be the same as or different from the one set in the above User Data field.
In this case, User Data is not necessary for stream configuration. That is, User Data in FIG.
The 71 field and the User Data 73 can be deleted. The image stream thus configured is transmitted to the receiving side. If the decoding display device on the receiving side has the configuration shown in FIG. 3, the displayed screen is consistent on the time axis. However, in the input stream analysis circuit 120 in FIG.
extra_ in the image Header 74
The value set in the field of information_Picture 81 is used.

Further, in the image data stream using the encoding method standardized by ISO / IEC13818-2, the GOP is surely performed for each Group of Pictures.
_Header is provided, and Pic is used as a non-display instruction signal.
temporal_ref in the true_Header
It is also possible to use a value equal to or larger than the number of pictures in the Group of Pictures as the value of erence. Generally, the time of Group of Picture is 0.5
~ 1 second. Therefore, Group of Pictur
In the case of NTSC frame, the number of pictures in e is
It is at most 30 and in the case of field it is at most 60. In the case of PAL, at most 25 in the case of frame.
And, in the case of the field, at most 50. Therefore, about 100 may be used as the non-display instruction signal. This time, in order to further confirm that the value of temporal_reference is equal to or larger than the number of pictures in the Group of Pictures, a number different from 100, for example, 1023 is used. Note that 1023 is the temporal_refer
It is the maximum value of ence. As a non-display instruction signal, te
general_reference = 1023 is used. Then, when decoding and displaying as usual, the values in the order of display are given or the original values are given. However, when the original value is 1023, the values in the displayed order must be re-added. In FIG. 5, te of the (i-1) th picture 10 and the (i + 2) th picture 13
The value of the general_reference is set to 1023. The values of temporal_reference of the (i + 1) th picture 12 and the ith picture 11 are
For example, 0 and 1, respectively.

In this way, the decoding display device as shown in FIG. 3 does not display the (i-1) th picture 10 upon reception, but the (i + 2) th picture 13 and (i + 1).
Display the 12th picture 12 and the i-th picture 11,
Images that are consistent on the time axis can be displayed. In FIG. 3, in the input stream analysis circuit 120, detection of the non-display instruction signal is performed by the temporary_reference.
nce value is used.

(Embodiment 4) An image stream transmission method according to Embodiment 4 of the present invention will be described.
FIG. 6 is a stream configuration diagram showing an image stream configuration at the time of backward transmission in the image stream transmission method according to the present invention, taking ISO / IEC13818-1 of MPEG2 as an example. An image stream transmission method according to the fourth embodiment will be described with reference to FIG. The difference between the fourth embodiment and the first to third embodiments is that stream control using an error indicator is added. In FIG. 6, 1 is an nth video stream (n is an integer), 2 is a cth audio stream (c is an integer), 3 is an mth video stream (m is an integer), 4
Is the d-th audio stream (d is an integer), 10 is the (i-1) -th picture (I picture), 11 is the (i) -th picture (B picture), and 12 is (i +).
1) th picture (B picture), 13 (i +
2) th picture (P picture), 14 is (j-
1) th picture, (i, j are integers), 90 is TSP
Header, 91 is payload, 92 is TSP header, 93
Is payload, 94 is TSP header, 95 is payload, 96 is Sync Byte (“47 (hexadecimal number)), and 97 is Transport_error_error_i.
ndicator, 98 are others. In addition,
Others 98 is simply described. Detail is,
See ISO / IEC 13818-1. (I + 2) th picture 13, (i + 1), which is a picture encoded by the encoding method using the correlation in the time axis direction.
Transspirt_error of the TSP header related to the 12th picture 12 and the (i) th picture 11
Activate the bit in _indicator97. Then, the TRANSPOIRT_ERR of the TSP header related to the (i-1) th picture 10, which is a picture encoded by an encoding method having no correlation in the time axis direction.
Deactivate the bit of or_indicator 97. In this way, the image stream is transmitted.
At this time, in the conventional decryption display device, Transpoir
Detects t_error_indicator97,
If active, a determination will be made that the payload involved contains an error and no decoding process is normally performed. That is, the screen is not displayed. Then, for a picture encoded by an encoding method having no correlation in the time axis direction, the Transpoi
The rt_error_indicator 97 is deactivated. Therefore, the displayed screen is only the picture coded by the coding method having no correlation in the time axis direction. If only a picture encoded by an encoding method having no correlation in the time axis direction is used, an image having no contradiction in the time axis direction is obtained even when transmitting in the backward direction of the time axis. That is, even a conventional decoding display device can display an image having no contradiction in the time axis direction. It should be noted that even for a part of the picture coded by the coding method having no correlation in the time axis direction, the Tran
The spot_error_indicator 97 may be activated. In this case, the number of screens to be displayed is reduced, and further frame-by-frame display is possible. Further, the fourth embodiment is based on ISO / I of MPEG2.
Although the description has been made using EC13818-1 as an example, even if other image coding with correlation in the time axis direction is used,
It goes without saying that it is possible. Further, in the decoding display device according to the present invention as shown in FIG. 3, when a stream having a reverse time axis direction is input, the input stream analysis circuit 120 causes the Trans of the TSP header to be transmitted.
Data is taken in regardless of the point_error_indicator 97. As a result, in the novel decoding display device as shown in FIG. 3, the (i) th picture 11, the (i + 1) th picture 12, and the (i
A decoding process is performed on the +2) th picture 13.
As described above, in both cases of the conventional decoding display device and the decoding display device according to the present invention, it is possible to display an image that is consistent on the time axis. When encoding with correlation in the time axis direction, in order to maintain the image quality while increasing the compression efficiency, the number of pictures encoded by the encoding method without the correlation in the time axis direction is inevitable. The number of pictures coded by a coding method having a correlation in the time axis direction is larger than that. Therefore, the decoding display device according to the present invention can obtain a screen with smoother motion than the conventional decoding display device.

(Embodiment 5) A reproducing apparatus according to Embodiment 5 of the present invention will be described. FIG. 8 is a signal processing block diagram relating to the reproducing apparatus according to the present invention. FIG. 10 is a diagram of relative values of PTS / DTS according to the ISO / IEC13818-1 standard of MPEG2. Signal processing in the reproducing apparatus according to the fifth embodiment will be described with reference to FIGS. 8 and 10. The difference between the fifth embodiment and the first to fourth embodiments is that MPEG2 is used.
ISO / IEC13818-1 standard PTS / D
The TS is rewritten according to the display time of the screen.

In FIG. 8, 130 is a PTS / DTS rewriting / adding circuit, 131 is a PTS / DTS calculation circuit,
Reference numeral 132 is a control circuit, 133 is a signal reproducing circuit, and 134 is a recording device. In FIG. 10, reference numeral 151 denotes a 0th picture, which is a picture (I) to be coded by a coding method that performs coding without using prediction in the time axis direction.
And a reference numeral 152 is a first picture, which is a picture (B picture) that performs coding by a coding method that performs coding using bidirectional prediction on the time axis.
Reference numeral 53 is a second picture, and a picture (B picture) is coded by a coding method that performs coding using bidirectional prediction of the time axis, and 154 is a third picture, which is a time axis. A picture (P picture) that is coded by a coding method that performs coding using prediction from the forward direction of
It is each picture. Furthermore, the transmission order of each picture and the value of PTS / DTS at the time of normal reproduction are described as relative values. For the sake of simplicity, we will play a forward 1/2 × slow screen. That is, the normal screen update cycle is doubled. Also,
In FIG. 10, PTS / D in the case of 1/2 throw
The relative value of TS is described. The signal processing circuit 133 is used to reproduce the image stream from the recording device 134. The image stream is M compliant with ISO / IEC13818
PEG2. Further, in the signal processing circuit 133, signal processing (reproduction processing, etc.) relating to the recording device of the reproduced image stream is performed, and the reproduction stream is converted into the MPEG2 format conforming to ISO / IEC13818,
Output to the PTS / DTS rewriting / adding circuit 130.
During normal reproduction, the PTS / DTS rewrite / addition circuit 130 does nothing with respect to the input reproduction stream, and outputs it to the transmission line as it is. The relative value of PTS / DTS at this time is shown during normal reproduction in FIG. In the case of NTSC, the difference in PTS or the difference in DTS is a number obtained by counting 1/30 seconds with a 27 MHz clock. In the case of PAL, the PTS difference or the DTS difference is a number obtained by counting 1/25 seconds with a 27 MHz clock.

Now, assume that 1/2 slow playback is performed. 1/2
When the slow speed is input to the control circuit 132, the control circuit 132 causes the signal reproduction circuit 133 to halve the stream reproduction rate from the recording device 134 on average.
Output an instruction signal such that At the same time control circuit 13
2 is the PTS / DTS calculation circuit 131
An instruction signal for doubling the value of / DTS is output.
The PTS / DTS calculation circuit 131 calculates the PTS value and the DTS value according to the instruction signal from the control circuit 132, and outputs them to the PTS / DTS rewriting / adding circuit 130. In the case of this embodiment, it is doubled. FIG. 10 shows the relative values of PTS / DTS at 1/2 throw. And
The output interval of the Transport Packet is set to be twice that of the normal playback. Mostly, for PCR, ISO /
As the standard of PCR of IEC13818-1, 10
It may not be possible to leave an interval of 0 msec or more. It is necessary to insert a PCR packet so as to comply with this PCR standard. By doing so, the time reference during slow playback can be accurately maintained, and slow playback is possible even with a conventional decoding display device. As described above,
The device that receives the reproduction stream from the transmission path can obtain a smooth reproduction image without any change. It goes without saying that not only the device that receives the reproduction stream from the transmission path but also a decoding display device that is integrated with the reproduction device may be used. Further, in the fifth embodiment, as an example, 1/2 slow is used, but it goes without saying that other speeds, for example, 1/3 slow are also acceptable. 1
In the case of / 3, the difference value of PTS / DTS becomes three times the value at the time of normal reproduction, and TransportSpac
The output interval of ket is three times that of normal reproduction.

(Sixth Embodiment) A reproducing apparatus according to the sixth embodiment of the present invention will be described. FIG. 7 is a block diagram of an image stream according to the present invention. FIG. 9 is a signal processing block diagram of the recording / reproducing apparatus according to the present invention. Figure 7
Signal processing in the reproducing apparatus according to the sixth embodiment will be described with reference to FIG. The sixth embodiment differs from the first to fifth embodiments in that the scene switching point is automatically detected and the scene switching point is recorded as an index in the recording device together with the image stream.

In FIG. 7, 1 is an n-th video stream (n is an integer), 2 is a c-th audio stream (c
Is an integer), 3 is an m-th video stream (m is an integer),
4 is the d-th audio stream (d is an integer), 10
Is the (i-1) th picture (I picture), 11 is the (i) th picture (B picture), and 12 is (i +
1) th picture (B picture), 13 (i +
2) th picture (P picture), 14 is (j-
1) th picture, (i, j are integers), 49 is PES
Header, 70 is Sequence Header, 71
Is User Data, 72 is GOP Header, 7
3 is User Data, 74 is Picture Hea
der, 100 is the Sequence Start Cod
e, 101 is H, V Size Value, 102 is A
Spec Ratio Frame Rate, 103 is Bit Rate, 104 is VBV Buffer Si
ze, 105 is Flag, 106 is Load Intr
a Quantizer Matrix, 107 is Int
ra Quantizer Matrix, 108 is L
oad NonIntra Quantizer Mat
rix, 109 is NonIntra Quantize
r Matrix, 110 is extension Hea
ders. Sequence He in FIG.
The structure in the ader 70 is simplified and described.
For details, refer to the MPEG2 ISO / IEC13818-2 standard.

In order to simplify the description, the MPEG / ISO / IE of MPEG2 is used as the image coding with correlation in the time axis direction.
Take the C13818-2 standard as an example. It goes without saying that other image coding methods that have correlation in the time axis direction may be used. If the scenes are the same, there is not much difference between neighboring pictures. That is,
The amount of data in the P picture or the B picture, which is a picture coded by the coding method using the correlation on the time axis, is relatively small. On the other hand, in different scenes, the pictures in the neighborhood are very different. Therefore, if the correlation on the time axis is used with the scene as a boundary, P
The amount of data for pictures and B pictures is relatively large. In FIG. 7, the (i + 1) th picture 12 is encoded based on the reference screen from the difference from the (i-1) picture 10. For example, it is assumed that there is a scene switch between the (i + 1) th picture 12 and the (i + 2) th picture 13 among the four pictures from the (i−1) th picture 10 to the (i + 2) th picture 13. Since the reference screen for encoding the (i + 1) th picture 12 is generated from the (i−1) th picture 10, it is considerably different from the (i + 2) th picture 13. Therefore, if the code amount of the (i + 2) th picture 13 is mc, the value is relatively large. On the other hand, when there is no scene switching among the four pictures from the (i-1) th picture 10 to the (i + 2) th picture 13, (i + 1)
The reference screen for encoding the 12th picture 12 is (i
-1) Although it is generated from the 10th picture 10,
There is not much difference from the (i + 2) th picture 13. Therefore, the (i + 2) th picture 1 in this case
When the code amount of 3 is mn, the value is relatively small. That is, mc >> mn. Therefore, for each picture performed by the same encoding method, that is, comparing the code amounts of I pictures, P pictures, and B pictures,
Remarkably, the time when the value of the code amount changes can be the scene switching point.

The MPEG2 ISO / IEC138
Although the 18-2 standard has been described as an example, it goes without saying that other image coding methods having correlation in the time axis direction may be used.

When quantization is used in the encoding process, in order to optimize the code amount, that is, to obtain the highest image quality with the smallest code amount, the quantization table for each scene is used. It is desirable to rewrite Therefore, In in the Sequence Header 70
tra Quantizer Matrix107 or Non Intra Quantizer Matrix
If x109 is detected and the value is significantly different from the previous value, it can be determined that the scene has changed. Then, the scene switching point is detected by the above scene switching method and registered as an index, so that the index can be automatically generated. This specific example will be described with reference to FIG. In FIG. 9, 140 is a scene change detection circuit, 141 is an index generation circuit, 14
2 is a signal recording circuit, 143 is a recording device, 144 is a signal reproducing circuit, 145 is a controller, 146 is a reproducing control circuit, 147 is a stream input line, and 148 is a stream output line. For simplicity, the image encoding method is MPEG2 ISO / IEC13818. First,
The time of recording will be described. The image stream is input to the scene switching detector 140 and the signal recording circuit 142 via the stream input line 147. The scene switching detector 140 detects a scene switching point. As described above, in the present invention, there are two methods for detecting scene switching points. One uses the difference amount of the code amount of the picture, and the other uses the change of the value of the quantization table. If a scene switching point can be detected, a signal indicating it (hereinafter referred to as a scene switching signal) is sent to the scene switching detector 140.
Is output to the index generation circuit 141. This signal may be, for example, the total picture number from the start of recording, the number of MPEG GOPs, or seconds / minutes / minutes.
Times such as hours may be used, or a combination of these may be used. The index generation circuit 141 generates an index based on the input scene switching signal. This index may be, for example, a table (hereinafter, referred to as a scene switching point table) of the time (hour / minute / second / frame) at which the scene switching point is switched to. The scene switching point table is output to the signal recording circuit 142 as one file. Further, the scene switching point table may be divided and output to the signal recording circuit 142. The signal recording circuit 142 converts the image stream input from the stream input line 147 into a recording signal optimum for the recording device 143 and outputs the recording signal to the recording device 143. Further, the index information which is an input signal from the index generation circuit 141 is converted into a recording signal most suitable for the recording device 143 and output to the recording device 143. At this time, the scene switching point table may be recorded as one file in a different location from the recording area of the image stream. Also,
It is also possible to divide the scene switching point table and record it at the relevant part of the image stream, including before and after it. For example,
If the scenes are switched at the A picture, there are a total of 11 scene switching points, which are about five scenes before the scene change point in time and five scenes behind the scene change point around the scene in A picture. Record near the recording area of the A picture. It should be noted that, here, it is assumed that there are around five in terms of time, but other values, for example, 10 may be used. Further, it is not necessary to record that the A picture is the scene switching point. next,
The playback time will be described. During reproduction, the reproduction control circuit 14
6 controls the recording device 143 to obtain a reproduction signal,
A reproduction signal is input to the signal reproduction circuit 144. The signal reproduction circuit 144 performs reproduction processing on the reproduction signal to generate an image stream, and outputs the image stream to the stream output line 148. further. Controller 145 for scene change point table
Output to. Since the normal reproduction is the same as the conventional one, the description thereof will be omitted and only the index search will be described.
The controller 145 holds the detected scene switching point table. Then, the user is notified of the information on the scene switching points held by the controller. The controller 145 notifies the reproduction control circuit 146 of the required scene switching point. The reproduction control circuit 146 calculates the position where the picture of the desired scene switching point is recorded, and requests the recording device 143 to reproduce the corresponding position. In the recording device 143, when the signal is reproduced, the signal is inputted to the signal reproducing circuit 144. The signal reproduction circuit 144 forms an image stream from the reproduction signal and outputs it. This time,
Transfer an image stream to the Transpoirt Packet
When outputting with, the start of the picture is Trans
If there is no alliance with the point packet, stuffing may be performed to form the alliance. As a result, the scene switching point can be displayed using the screen as an index when necessary.
The user can select the viewing screen from the index screen, and if one index screen is selected,
The time is held in the controller 145. Based on the information from the controller 145, the reproduction control circuit 146 calculates the read position in the recording device 143 and realizes reproduction from the corresponding location. It should be noted that the embodiment has been described by taking MPEG2 as an example of the image coding having the correlation in the time axis direction, but other image coding having the correlation in the time axis direction may be performed. Needless to say.

(Embodiment 7) An image stream transmission method according to Embodiment 7 of the present invention will be described.
FIG. 11 is a stream configuration diagram showing an image stream configuration at the time of backward transmission in the time axis direction and an image stream configuration at the time of thinning out a display picture at the time of backward transmission in the time axis direction in the image stream transmission system according to the present invention. FIG. 4 is a stream configuration diagram showing. In FIG. 11, the picture indicated by the broken line is a so-called hidden picture in which the decoding process is performed but the screen is not displayed. An image stream transmission method according to the seventh embodiment will be described with reference to FIG. The seventh embodiment is different from the first to sixth embodiments in that a display image is re-transmitted in order to generate a screen to be displayed, and the display image depends on the performance of a communication channel or a decoder. If you need to decimate,
This is a point of thinning out display images. 17 in FIG.
0 is the first I2 picture, 171 is the first B0 picture, and so on, 181 is the first B10 picture, 182 is the second I2 picture, and so on.
193 is a second B10 picture. Since the encoding using the correlation on the time axis is used, the B picture needs to generate a reference screen that is the source of the encoding. This reference screen is a picture that is temporally before and after the B picture. Therefore, in order to decode the B picture,
In advance, it is necessary to transmit the I picture or P picture serving as the reference screen. On the time axis, forward image streams are transmitted in the order shown by the forward arrows in FIG. Then, the I picture and the P picture are not decoded and displayed on the screen immediately,
After the B picture is displayed, the screen is displayed. On the other hand, transmission of the forward image stream on the time axis requires transmission of the I picture or P picture, which is the reference screen, in order to decode the B picture. However, the decoding display device cannot hold a large number of baseband picture data serving as a reference screen. This is because a large capacity memory circuit is required. In particular, the amount of data for a High Definition image is 1 × 10 ⁹ bits, which is huge.
Not feasible. Therefore, if a different reference picture is needed after decoding the B picture, the image stream required for the reference picture is transmitted again. Using FIG. 11,
This situation will be briefly described. Now, after displaying up to the second B6 picture 189, it is transmitted in the opposite direction on the time axis.
The next display screen is the second P5 picture 185. Then, the second B4 picture 187 and the second B3 picture 186 follow. A second I2 picture 182 is required for these decodings. Therefore, the second I2 picture 182 is transmitted as a non-display picture (picture that performs decoding but does not display on the screen). Similarly, the second
B1 picture 184 and second B0 picture 183
The image stream from the first I2 picture 170 to the second I2 picture 182 needs to be transmitted for the screen display. Further, in order to display the first P11 picture 179 to the first B9 picture 180 on the screen, the transmission from the first I2 picture 170 to the first P11 picture 179 is performed again. Similarly, in order to display the first P8 picture 176 to the first B6 picture 177 on the screen, the transmission from the first I2 picture 170 to the first P8 picture 176 is performed again. In this way, by retransmitting the image stream required to generate the reference screen, not only does the decoding display device side not need to have an enormous memory, but the decoding procedure becomes almost the same as usual and Due to the direction, it is not necessary to go through a complicated decoding procedure. Moreover,
The retransmitted image stream is only the I picture and P picture streams necessary for generating the reference screen. That is, the B picture stream in the middle is not transmitted. This results in efficient transmission. Furthermore, when the image transmission rate cannot be set high due to the performance of the communication channel or the decoding display device, the display screen may be thinned. Comparing the configuration diagram of the backward image stream in FIG. 11 with the configuration diagram of the backward thinned image stream, the backward thinned image stream configuration diagram is from the first P11 picture 179 to the first B9 picture 180. Thinning out. Therefore, the image stream from the first I2 picture 170 to the first B9 picture 180, which is the image stream during this period, is not transmitted. In this way, the transmission band of the image stream can be reduced, and the system as a whole does not break down.

[0048]

As described above, according to the image stream transmission method, the decoding display device, the playback device, the scene switching point detection method, and the recording / playback device according to the present invention, slow motion and reverse slow motion can be achieved with a simple device. This can be realized, and furthermore, the switching point of the scene can be detected by a simple device.

[Brief description of drawings]

FIG. 1 is an image stream configuration diagram according to a first embodiment of the present invention.

FIG. 2 is an example diagram of an encoding method according to Embodiment 1 of the present invention in which correlation is provided in a time axis direction.

FIG. 3 is a block diagram of a decoding display device according to the first to fourth embodiments of the present invention.

FIG. 4 is an image stream configuration diagram at the time of backward transmission in the time axis according to the second embodiment of the present invention.

FIG. 5 is an image stream configuration diagram during time-axis backward transmission according to the third embodiment of the present invention.

FIG. 6 is an image stream configuration diagram at the time of backward transmission in the time axis according to the fourth embodiment of the present invention.

FIG. 7 is an image stream configuration diagram at the time of backward transmission in the time axis according to the sixth embodiment of the present invention.

FIG. 8 is a block diagram of a playback device according to a fifth embodiment of the present invention.

FIG. 9 is a block diagram of a recording / reproducing apparatus according to a sixth embodiment of the present invention.

FIG. 10 is a PTS / DTS according to a fifth embodiment of the present invention.
Example of value of

FIG. 11 is an example diagram of image stream transmission according to the seventh embodiment of the present invention.

[Explanation of symbols]

1 nth video stream 2cth audio stream 3mth video stream 4 d th audio stream 10 i-1st picture 11 i th picture 12 i + 1st picture 13 i + 2nd picture 14 j-1st picture 20 header 21 Payload

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Atsuo Ochi             1006 Kadoma, Kadoma-shi, Osaka Matsushita Electric             Sangyo Co., Ltd. (72) Inventor Yasuaki Toyama             1006 Kadoma, Kadoma-shi, Osaka Matsushita Electric             Sangyo Co., Ltd. F-term (reference) 5C053 FA23 GA11 GB06 GB29 GB37                       HA23 HA25 JA21 LA14                 5C059 LB07 MA00 MA05 PP05 PP06                       PP07 PP14 RC12 SS16 TA07                       TA71 TB04 TC21 UA02 UA05

Claims (20)

[Claims] 1. A method of transmitting an image stream using image encoding having a correlation in the time axis direction, wherein the image stream image encoding is decoded but the decoded image data is not displayed on the screen. A non-display instruction signal indicating that is held in the image stream and transmitted. 2. The image stream according to claim 1, wherein when a sequence changing screen whose image display decoding order is different from a screen display order is held, a non-display instruction signal is held in said order changing screen. Transmission method. 3. When the screen is updated in the forward direction and an order-changed screen exists, a non-display instruction signal is held in a part or all of the coded pictures other than the bidirectional prediction in the time axis direction. The image stream transmission method according to claim 2, wherein 4. A picture having a non-display instruction signal according to any one of claims 1 to 3 is subjected to image coding decoding processing, but screen display is not performed, and the non-display instruction signal is not held. A decoding display device characterized by performing a decoding process of image coding on a picture to display a screen. 5. The image stream is ISO / IEC138.
A non-display instruction signal, which is an image stream using an encoding method standardized by ISO 18, is ISO / IEC13818.
4. The image stream transmission method according to claim 1, wherein the signal is a signal that is used by changing the existing value of. 6. The image stream is ISO / IEC138.
A non-display instruction signal, which is an image stream using an encoding method standardized by ISO 18, is ISO / IEC13818.
4. The image stream transmission method according to claim 1, wherein the signal is a signal to be used by adding the spare area to the image stream. 7. The image stream is ISO / IEC138.
A non-display instruction signal, which is an image stream using an encoding method standardized by ISO 18, is ISO / IEC13818.
4. The image stream transmission method according to claim 1, wherein the signal is used by changing the meaning of the existing signal. 8. A transmission of a communication path when a reproduction other than normal reproduction is performed on the image stream from a storage device which records an image stream using image encoding having a correlation in the time axis direction and the image stream is transmitted. A method for transmitting an image stream, characterized in that the picture to be displayed is thinned according to the capability or the decoder capability of decoding the image coding. 9. An image stream transmission using image coding having a correlation in the time axis direction, wherein the screen display is performed by reversing the update order of the screen, and thus the image coding is decoded. A method for transmitting an image stream, which comprises retransmitting only a necessary stream. 10. An image stream transmission using image encoding having a correlation in a time axis direction, wherein a decoding device at a transmission destination performs a decoding process of image encoding of an image stream, but a decoded image. Investigate whether the decoding device is compatible with a non-display instruction signal indicating that data is not displayed on the screen or is not compatible with the non-display instruction signal. If the decoding device is incapable of supporting the signal in the image stream and transmitting the image stream, the non-display instruction signal may not be held in the image stream, and encoding without correlation in the time axis direction may be performed. A method for transmitting an image stream, which comprises transmitting an image stream of only the performed picture. 11. An image stream transmission using image encoding having a correlation in the time axis direction, wherein the image is transmitted to a picture other than a picture that has been encoded and has no correlation in the time axis direction for screen display. An image stream transmission method characterized by outputting with an error flag. 12. An image stream transmission using an encoding method standardized by ISO / IEC13818-1, comprising:
As an error flag, Transport_error_indicator of ISO / IEC13818-1
12. The image stream transmission method according to claim 11, characterized in that. 13. An image stream using an encoding method standardized by ISO / IEC13818-1 is recorded, the recorded image stream is reproduced, and the display time of the screen is changed and displayed. In this case, rewrite the time management signal that is performing time management to a predetermined value,
A reproducing apparatus, which outputs an image data stream to a decoding apparatus. 14. When PTS and DTS are selected as time management signals when slow-displaying 1 / n (n is a natural number) of screen updates in the forward direction, PTS and DTS are selected.
The difference value for each picture is (1 / f) × n seconds (f is NT
14. The reproducing apparatus according to claim 13, wherein the PTS and DTS are rewritten so as to be 30 for SC and 25 for PAL. 15. A Sequence as a time management signal.
The playback device according to claim 13 or 14, wherein frame_rate_code of Header is selected. 16. A reproduced image data stream has a difference value of (1/30) × for each picture of PTS and DTS when a screen update is displayed slowly in a forward direction of 1 / n (n: natural number). PTS and D to be n seconds
Not only rewriting TS, but also Transport
16. The reproducing apparatus according to claim 13, wherein the output interval of the packet is also n times that of the normal reproduction. 17. A method of detecting a scene switching point of an image stream using image coding having a correlation in the time axis direction, wherein a point at which information in the image stream greatly changes is determined as scene switching. A method for detecting a scene switching point, which is characterized in that 18. The method for detecting a scene switching point according to claim 17, wherein the point at which the information greatly changes is a point at which the picture data amount of the same encoding means greatly changes. 19. A method for detecting a scene switching point of an image data stream using an encoding method standardized by ISO / IEC13818-2, wherein a point at which information largely changes is a value in a quantization table in Sequence_Header. 18. The point at which is changed.
The scene switching point detection method described. 20. A recording / reproducing apparatus, wherein a scene switching point is registered and recorded as an index, and the scene switching point is used as an index search during reproduction.