JP2001157177A - Device and method for transmitting digital data and recording medium with recorded transmitting program - Google Patents

Abstract

PROBLEM TO BE SOLVED: To multiplex digital data to one frame period (valid video period) of a television signal and to transmit the multiplexed digital data, even when the transmission of data corresponding to a reproducing speed except for the speed of an integral multiple is requested. SOLUTION: This device is provided with a reproducing means for reproducing digital data at a speed requested from the outside, a flag-preparing means for preparing a flag showing, whether digital data reproduced by the said reproducing means are valid or invalid on the basis of the reproducing speed for each frame, a multiplexing means for providing at least one transmitting area in one frame period of the television signal on the basis of the reproducing speed, multiplexing the flag prepared by the said flag preparing means to the digital data from the reproducing means and locating these multiplexed digital data in the transmitting area, and a transmitting means for transmitting the digital data multiplexed by the said multiplexing means and while using the flag, data are transmitted corresponding to the reproducing speed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a digital data transmission apparatus for multiplexing and transmitting digital data including video data and audio data, and more particularly to a digital data transmission apparatus for multiplexing and transmitting digital data during an effective video period of a television signal. The present invention relates to a transmission device, a transmission method, and a recording medium on which a transmission program is recorded.

[0002]

2. Description of the Related Art Currently, broadcasting stations around the world use the SMPTE-259M standard, that is, a serial digital interface (Serial D
digitalInterface (hereinafter referred to as "SDI") standard. As is well known, the SDI standard is based on the Society of Motion Picture and Television Engineers (SMPTE).
ICT and Television Engineers), and stipulates that digital data including video data and audio data be converted to serial data and transmitted. By using the SDI standard as described above, the digital data transmission apparatus transmits, for example, a one-channel 4: 2: 2 component television signal without passing through an analog transmission system to prevent deterioration of the signal. I have. In addition, there is a problem for a broadcasting station to effectively use stored digital data (material data) for a program in order to cope with multi-channels accompanying the development of digital broadcasting. For this reason, it is known that a broadcasting station performs data transmission by connecting a digital data transmission device between an editing device exemplified by a non-linear editing device and a recording medium or recording / reproducing device holding material data. Have been.

[0003] In the digital data transmission apparatus as described above, as an application example of transmitting digital data of a plurality of channels including video data encoded with high efficiency through a digital interface, a case where data is transmitted at high speed from a recording medium is considered. Can be For example, data is reproduced from a recording medium at a high speed of, for example, 4 times speed, and data of four channels is multiplexed and transmitted on a transmission path corresponding to the SDI standard or the like. As a result, the time required for data transmission can be reduced to 1/4. In this case, in a video signal of the same material, data for four frames that are temporally continuous are multiplexed and transmitted as data of four channels in a video effective period of one frame. As a conventional digital data transmission apparatus for performing such data transmission, for example, WO
There is a technique of "digital data transmission apparatus and transmission method thereof" disclosed in Japanese Patent Application Laid-Open No. 98/59492. In this conventional digital data transmission apparatus and its transmission method, when multiplexing highly efficient coded digital data of a plurality of channels in an effective video period of a television signal and transmitting the multiplexed data, the data is received by a device on the receiving side of the transmission path. The main purpose is to perform data processing in order.

[0004] Here, referring to FIG. 18, the above-mentioned conventional digital data transmission apparatus and its transmission method will be described.
This will be specifically described. In the following description, a case will be described in which data compressed based on the DV format is multiplexed and transmitted in an effective video period of an NTSC television signal. FIG. 18 is a block diagram showing a configuration of a conventional digital data transmission device. As shown in FIG. 18, this conventional digital data transmission apparatus includes a reproduction data 151 and a reproduction data 151 from a magnetic tape 100 as a recording medium.
A memory 101 for rearranging 152, 153, 154 into data in frame units, and a memory controller 102 for controlling the memory 101 are provided. In a conventional digital data transmission apparatus, reproduction data processors 103, 104, 105, and 106, which receive reproduction data 155, 156, 157, and 158 rearranged in frame units from a memory 101 and perform demodulation processing, respectively, and Error correction decoders 107, 108, 109 and 110 are connected to the reproduction data processors 103 to 106 and perform error correction decoding of the input reproduction data.

The reproduced data 151 to 154 are simultaneously reproduced from the magnetic tape 100 by four heads (not shown) and input to the memory 101 serially.
Further, the magnetic tape 100 is running at a speed four times as fast as the normal reproduction in order to perform a quadruple speed high speed reproduction. The error correction decoders 107 to 110 perform error correction decoding processing of the reproduction data input from the reproduction data processors 103 to 106, respectively, based on the parity added at the time of recording. The error correction decoders 107 to 110 provide DIF data 15 including compressed video data, audio data, VAUX data, AAUX data, and subcode data.
9, 160, 161, 162 are output. still,
For specific information indicated by VAUX data, AAUX data, and subcode data, see, for example,
See No. 26022.

Further, the conventional digital data transmission apparatus includes memories 111, 112, 113, 114 connected to error correction decoders 107 to 110, respectively, and a memory controller 11 for controlling the memories 111 to 114.
5, and the multiplexer 1 connected to the memories 111 to 114
16 is provided. This conventional digital data transmission apparatus includes a DIF encoder 117 connected to a multiplexer 116 and a memory 118 connected to the DIF encoder 117. Memory 111 to 11
4 is a write control signal 16 from the memory controller 115
3, the DIF data 159 to 162 are written and held, respectively. Also, the memories 111 to 114
Is a read control signal 16 from the memory controller 115
4, 165, 166, and 167, and reads the held DIF data 159 to 162, respectively, and outputs the read DIF data to the multiplexer 116. As a result, the DIF data 159
162, the time axes in the transmission order are shifted from each other,
The data is output from the multiplexer 116 as multiplexed DIF data 168.

[0007] The DIF encoder 117 packetizes the multiplexed DIF data 168 for output to the digital interface, inserts an ID, and arranges the DIF packet on a predetermined line. The arrangement of the DIF packets is performed in line units in four transmission areas provided in the memory 118 (details will be described later). A driver 119 and an output terminal 120 are sequentially connected to the DIF encoder 117. Driver 119
Encodes the DIF packet input from the DIF encoder 117 for data transmission (channel coding)
And outputs it to the output terminal 120. Output terminal 120
Is connected to a transmission line (not shown) such as a coaxial cable, and multiplexed data is sequentially transmitted.

Hereinafter, the operation of the conventional digital data transmission apparatus will be specifically described with reference to FIG.
In the following description, VAUX data multiplexed on DIF data 168, AAUX
Description of the processing of data and subcode data is omitted. First, reproduction data 151 to 154 are read in parallel from the magnetic tape 100 by four heads,
It is written into the memory 101 once. Each of these reproduction data 151 to 154 is data for one frame, and is reproduced from the magnetic tape 100 in units of tracks. For this reason, in the memory 101, the memory controller 1
Under the control of 02, a process of rearranging the data into data of one frame unit is performed. Next, the reproduction data 155 to 158
From the memory 101 to the reproduction data processors 103 to 106
Are read out in parallel. These reproduction data 155 to 158 are data in units of frames. The order of the reproduction data 155 to 158 on the time axis is k, (k + 1),
(K + 2) and (k + 3) th frames.

Next, each of the reproduction data processors 103-106
Then, the reproduced data 155 to 155, which are still modulated,
158 are respectively performed. Thereafter, the reproduction data processors 103 to 106 output the demodulated data to the connected error correction decoders 107 to 110, respectively. Subsequently, each of the error correction decoders 107 to 110 performs an error correction decoding process on the input data based on the error correction parity added at the time of recording.
162 are written to the memories 111 to 114, respectively. Next, the memories 111 to 114 and the multiplexer 116
Then, a multiplexing process of multiplexing four channels of DIF data 159 to 162 input in parallel into one processing system is performed. In the following description, the systems to be processed by the memories 111 to 114 are defined as channel 1, channel 2, channel 3, and channel 4, respectively.

More specifically, the DIF data 159 to 162 for one frame are written into the corresponding memories 111 to 114 at the same timing based on the write control signal 163 from the memory controller 115, respectively. At the time of reading, these DIF data 159 to 162 need to be multiplexed in order from channel 1 on the time axis. Therefore, the memory controller 115 first reads out the DIF data 159 for one frame of channel 1 from the memory 111, and thereafter reads out the channel 2, channel 3,
Then, the DIF data 160 to 162 for one frame are read from the memories 112 to 114 in the order of channel 4. Therefore, the memory controller 115 outputs the write control signal 163 to all the memories 111 to 14 at the same timing. On the other hand, the memory controller 115
Are the DIF data 159 to 162 of each channel 1 to 4
The read control signals 164 to 167 are output to the memories 111 to 114 in accordance with the read positions.

Subsequently, in the multiplexer 116, the memory 11
DIF for one frame read sequentially from 1 to 114
Data 159 to 162 are multiplexed on the time axis for each of channels 1 to 4 and output as one system of DIF data 168. The multiplexing process is performed by the DIF of each channel 1-4.
Since the data 159 to 162 are compressed on the time axis in a time axis compression process, the read operation from the memories 111 to 114 is performed at four times the frequency of the write operation.
After that, the DIF data 168 multiplexed by the multiplexer 116 is input to the DIF encoder 117. D
The IF encoder 117 receives the input DIF data 16
8 is packetized, and a packet header as identification information of the packet, parity for error correction, and the like are added. further,
The DIF encoder 117 arranges DIF packets of each of the channels 1 to 4 on a predetermined line according to the SDI standard with respect to four transmission areas provided in the memory 118.
As a result, the DIF packet is multiplexed on a predetermined line in an effective video period of one frame according to the SDI standard. Then, encoding for data transmission is performed by the driver 119, and data obtained by multiplexing DIF packets according to the SDI standard is output from the output terminal 120 to the outside.

[0012] Referring to FIG. 19, the DI of four channels is set in the effective video period of one frame according to the SDI standard.
A transmission method for arranging and transmitting F packets will be specifically described. FIG. 19 is an explanatory diagram showing a method of arranging DIF packets of four channels in an effective video period of one frame specified by the SDI standard in the conventional digital data transmission device shown in FIG. As shown in FIG. 19, 1 in a television signal specified by the SDI standard
The frame is divided into four transmission areas corresponding to the four channels 1 to 4 on a line basis. That is, each transmission area of channels 1 to 4 is assigned a predetermined number of lines, for example, 94 lines. More specifically, as shown in the figure, DIF packets of channel 1 are arranged on lines 21 to 114 and multiplexed. Similarly, the DIF packet of channel 2 is the first
15th to 208th line, DIF of channel 3
The packets are arranged on lines 284 to 377 and the DIF packets of channel 4 are arranged on lines 378 to 471 and multiplexed.

The number of DIF packets in each of the channels 1 to 4 is 750 packets per frame. That is, DIF data for one frame is generated into 750 DIF packets by the DIF encoder 117 (FIG. 18). These DIF packets are multiplexed by 8 packets per line, and are sequentially transmitted in a predetermined line unit. These DIF packets are arranged by writing data in four transmission areas set in the memory 118 (FIG. 18) corresponding to each of the channels 1 to 4. As described above, in this conventional digital data transmission apparatus and its transmission method, the D
IF packets are time-division multiplexed on a line-by-line basis and transmitted in the same order as recorded on the magnetic tape 100. As a result, in the conventional digital data transmission apparatus and transmission method thereof, data transmission is performed at a reproduction speed of, for example, 4 times speed without requiring a process such as rearrangement of data in a receiving apparatus.

[0014]

In the above-described conventional digital data transmission apparatus and its transmission method, when performing data transmission corresponding to a reproduction speed of N times speed (N is an integer), N data is added to the effective video period. A plurality of transmission areas are set, and DIF packets of data to be transmitted in each transmission area are arranged and transmitted in line units. For this reason, in the conventional digital data transmission apparatus and its transmission method, when data transmission corresponding to a reproduction speed other than the integer multiple speed is requested, the transmission area is shifted to the effective video period in accordance with the requested reproduction speed. Could not be set to.
Therefore, this conventional digital data transmission apparatus and its transmission method cannot perform data transmission corresponding to a reproduction speed other than the integer multiple speed, for example, 1.5 times speed.
As a result, according to the conventional digital data transmission apparatus and its transmission method, for example, when used for processing and editing processing of material data for a program, data transmission corresponding to a desired reproduction speed cannot be performed. It is difficult to process and edit material data to improve or make the program contents more effective on the device on the side.

In the data transmission, the reproduction (transmission) speed is limited depending on the configuration and performance of the receiving apparatus. Specifically, when the digital data transmission device transmits data to the recording / reproducing device, for example, even if the data is transmitted at a quadruple speed, the recording / reproducing device on the receiving side directly stores the data on the recording medium at the quadruple speed. In some cases it was impossible to write. However, in order to reduce the transmission time in data transmission and further the data processing time in the receiving device, it is desirable to transmit data at the maximum playback speed that can be supported by the receiving device in data transmission. Things. However, in the above-mentioned conventional digital data transmission apparatus and its transmission method, data cannot be transmitted at a desired reproduction speed other than an integral multiple, so that the transmission time and the data processing time in the receiving apparatus must be reduced. Was not easy.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-described problems. Even when data transmission corresponding to a reproduction speed other than the integral multiple speed is required, one frame period (one frame period) of a television signal is required. It is an object of the present invention to provide a digital data transmission device, a transmission method, and a recording medium on which a transmission program is recorded, in which digital data is multiplexed during an effective video period and the multiplexed data can be transmitted.

[0017]

SUMMARY OF THE INVENTION A digital data transmission apparatus according to the present invention is a digital data transmission apparatus for multiplexing and transmitting digital data during one frame period of a television signal. Reproducing means for reproducing the digital data at, and flag generating means for generating a flag for each frame based on the reproducing speed, indicating that the digital data reproduced by the reproducing means is valid data or invalid data. Providing at least one transmission area in the one frame period based on the playback speed, multiplexing the flag created by the flag creation means with digital data from the playback means, and multiplexing the multiplexed digital data Multiplexing means for arranging the data in the transmission area, and data multiplexed by the multiplexing means. And a transmitting means for transmitting the digital data, by using the flag, and configured to perform data transmission corresponding to the reproduction speed. With this configuration, even when data transmission corresponding to a reproduction speed other than the integer multiple speed is requested, digital data can be multiplexed in one frame period of a television signal and the multiplexed data can be transmitted. it can.

A digital data transmission method according to the present invention is a digital data transmission method for multiplexing and transmitting digital data in one frame period of a television signal, wherein the digital data is reproduced at an externally requested reproduction speed. Playing step, based on the playing speed,
A creating step of creating, for each frame, a flag indicating that the digital data reproduced in the reproducing step is valid data or invalid data; and, based on the reproducing speed, at least one transmission area in the one frame. Provided in the period, the flag created in the creating step is multiplexed with the digital data reproduced in the reproducing step,
A multiplexing step of arranging the multiplexed digital data in the transmission area; and a transmission step of performing data transmission corresponding to the reproduction speed using the flag created in the creation step. With this configuration, even when data transmission corresponding to a reproduction speed other than the integer multiple speed is requested, digital data can be multiplexed in one frame period of a television signal and the multiplexed data can be transmitted. it can.

The recording medium on which the transmission program of the present invention is recorded can reproduce digital data at a reproduction speed requested from the outside, and, based on the reproduction speed, the digital data to be reproduced can be valid data or invalid data. Creating a flag for each frame, based on the playback speed, providing at least one transmission area in one frame period of the television signal, and multiplexing the created flag with the reproduced digital data. And arranging the multiplexed digital data in the transmission area, and performing data transmission corresponding to the reproduction speed using the created flag. With this configuration, even when data transmission corresponding to a reproduction speed other than the integer multiple speed is requested, digital data can be multiplexed in one frame period of a television signal and the multiplexed data can be transmitted. it can.

[0020]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, preferred embodiments showing a digital data transmission apparatus and a transmission method according to the present invention will be described.
This will be described with reference to the drawings. In the following description, in order to facilitate comparison with a conventional example, a case where digital data is transmitted during an effective video period of an NTSC television signal based on the SDI standard will be described. . The digital data to be transmitted is, for example, D
25Mbps per frame based on V format
Is compressed at a data rate of

<< First Embodiment >> First, the above-mentioned S used by the digital data transmission apparatus of the present embodiment for data transmission is described.
One frame period in the DI standard will be specifically described. FIG. 1 is an explanatory diagram showing a configuration of one frame according to the SDI standard. Note that a straight line H in FIG. 1 indicates a horizontal pixel of a television signal, and a numerical value on the straight line H indicates a pixel number. A straight line V in the figure indicates a vertical line of the television signal, and a numerical value on the straight line V indicates a line number.
As shown in FIG. 1, in the SDI standard, one frame period includes a horizontal blanking period, a vertical blanking period in each of a first field and a second field constituting one frame, an optional blanking period,
And an effective video period. The horizontal blanking period is defined by a section of horizontal pixels from pixel numbers 1440 to 1715. During the horizontal blanking period, the EAV (End of Act)
ive Video) and SAV (Start of Active Video). In the horizontal blanking period between these EAV and SAV, ancillary data such as audio data and user data can be transmitted.

In the effective image period, 1440 is provided for each line.
The video data of the pixel is multiplexed and transmitted as serial data at a predetermined clock frequency. Note that one pixel is composed of 8-bit or 10-bit video data. The optional blanking period is a period included in the vertical blanking period, and can arrange and transmit video data similarly to the effective video period. In the digital data transmission apparatus of this embodiment, as will be described in detail later, based on the requested reproduction speed, at least one transmission area is provided in the above-described effective video period of one frame period, and the digital data is transmitted. A flag indicating valid data or invalid data is created for each frame. Further, the digital data transmission apparatus according to the present embodiment is configured to perform data transmission corresponding to the reproduction speed by using the created flag. As a result, the digital data transmission apparatus of the present embodiment can perform data transmission corresponding to a reproduction speed other than the integral multiple speed.

Next, the digital data transmission apparatus according to the present embodiment will be specifically described with reference to FIG. In the following description, for the sake of simplicity, the hard disk drive reproduces digital data including material data for a program through an output system of two channels, and transmits data corresponding to a requested reproduction speed. The configuration to be performed will be described as an example. FIG. 2 is a block diagram showing the configuration of the digital data transmission device according to the first embodiment of the present invention. As shown in FIG. 2, a digital data transmission apparatus according to the present embodiment includes a hard disk device 1 storing digital data including video data and audio data accompanying the video data, and a reproduction data processing device connected to the hard disk device 1. Error correction decoders 4 and 5 which are connected to the reproduction devices 2 and 3 and the reproduction data processors 2 and 3, respectively, and perform error correction decoding processing of the input reproduction data. The hard disk drive 1 includes a plurality of disk-shaped recording media and a head for inputting and outputting digital data to and from each recording medium. The hard disk drive 1 includes a motor for rotating the recording medium at a predetermined number of rotations and a positioning mechanism for positioning the head. The hard disk device 1 receives read instruction information 61 from a system controller 12 described later, and reproduces digital data from a recording medium at a reproduction speed specified by the read instruction information 61. The hard disk device 1 outputs the reproduced data 51 and 52 of the reproduced channels 1 and 2 to the reproduction data processors 2 and 3 in frame units.

The reproduction data processors 2 and 3 store reproduction data 5
1 and 52 are input and demodulated, and output to the connected error correction decoders 4 and 5, respectively. The error correction decoders 4 and 5 perform error correction decoding of the reproduction data input from the reproduction data processors 2 and 3 based on the parity added at the time of recording, and compress the compressed video data and audio data. , DIF data 53 including VAUX data, AAUX data, and subcode data,
54 are output. In the digital data transmission apparatus of the present embodiment, the above-described hard disk drive 1, the reproduced data processors 2 and 3, and the error correction decoders 4 and 5
A reproducing means for reproducing digital data at a reproducing speed requested from the outside is constituted.

The digital data transmission apparatus of this embodiment is
Preferably, the memories 6 and 7 are each constituted by a FIFO memory and connected to the error correction decoders 4 and 5, respectively, a memory controller 8 for controlling the memories 6 and 7, and connected to the memories 6 and 7, respectively. DIF flag multiplexers 9 and 10 are provided. Further, the digital data transmission apparatus of this embodiment includes DIF flag multiplexers 9 and 10
, A system controller 12 for controlling the entire transmission apparatus, a DIF encoder 13 connected to the DIF data multiplexer 11, and a memory 14 connected to the DIF encoder 13. Is provided. The memories 6 and 7 store the DIF data 5 based on the write control signal 55 from the memory controller 8.
3 and 54 are written and held, respectively. The memories 6 and 7 store a read control signal 5 from the memory controller 8.
6, 57 based on the DIF data 53,
54 are read from the DIF flag multiplexers 9 and 10, respectively.
Respectively.

The system controller 12 preferably has a CPU
Alternatively, it generates the DIF flags 58 and 59, the transmission speed information 60, and the read instruction information 61 based on the reproduction speed externally requested by the MPU. Specifically, when the system controller 12 externally inputs a request for transmitting digital data held in the hard disk device 1, the system controller 12 transmits the transmission speed information 60, based on the reproduction speed included in the transmission request. And the read instruction information 61 is created. The system controller 12 transmits the created transmission speed information 60 to the DIF data multiplexer 11
The read instruction information 61 is output to the IF encoder 13 and output to the hard disk device 1. Further, the system controller 12 controls the DIF based on the playback speed.
Flags 58 and 59 are created for each frame and output to DIF flag multiplexers 9 and 10, respectively. In the digital data transmission apparatus of the present embodiment, the system controller 12 sets a DIF flag indicating that the digital data reproduced by the above-mentioned reproducing means is valid data or invalid data based on the requested reproduction speed. This constitutes a flag creating means for creating each frame.

Each DIF flag 58, 59 is a flag for indicating that the DIF data 53, 54 of the corresponding channel is valid data or invalid data. For example, when the DIF data 53, 54 is valid data, it is "0". Is set, and “1” is set when the data is invalid. These D
IF flags 58 and 59 are DIF flag multiplexers 9 and 10
Accordingly, the DIF data 53 and 54 are respectively arranged at predetermined multiplex positions of the DIF data 53 and 54 and are transmitted to the transmission-side receiving apparatus. The transmission speed information 60 is information indicating a transmission speed in data transmission determined based on the above-mentioned requested reproduction speed, and is arranged at a predetermined multiplexing position by the DIF data multiplexer 11 and is a transmission destination reception side. Transmitted to the device. The read instruction information 61 includes information for designating the requested reproduction speed and the digital data to be transmitted. The read instruction information 61 includes the order of frames output from the hard disk device 1 to each of the reproduction data processors 2 and 3. The order of this frame is
It is determined in association with the created DIF flags 58 and 59.

The DIF data multiplexer 11 shifts the DIF data 53 and 54 from the DIF flag multiplexers 9 and 10 on the time axis in the transmission order and multiplexes the multiplexed DIF data.
The data is output to the DIF encoder 13 as IF data 62. The DIF encoder 13 performs packetization for outputting the multiplexed DIF data 62 to the digital interface, insertion of an ID, and arrangement of DIF packets. The DIF encoder 13 acquires the transmission speed information 60 from the system controller 12. DIF encoder 13
Provides at least one transmission area in an effective video period (one frame period) based on the acquired transmission speed information 60. More specifically, in the digital data transmission apparatus according to the present embodiment, the DIF encoder 13 outputs a reproduction speed other than the integer multiple speed, for example, a pq multiple speed (p, q is 1 to 9).
Is requested, the DIF encoder 13 receives the transmission speed (p + 1) times as indicated by the transmission speed information 60, and divides the (p + 1) transmission areas into the effective video period (1).
(Frame period). The DIF encoder 13 stores a DIF in a transmission area provided in the memory 14 as described later in detail.
IF packets are arranged in line units.

The memories 6, 7 and the memory controller 8, D
IF flag multiplexers 9 and 10, DIF data multiplexer 1
1, at least one transmission area is provided by the DIF encoder 13 and the memory 14 in the one frame period based on the requested reproduction speed, and the flag generated by the flag generation means is transmitted from the reproduction means. The multiplexing means constitutes multiplexing means for multiplexing digital data and arranging the multiplexed digital data in a transmission area. In the digital data transmission apparatus of the present embodiment, a driver 15 and an output terminal 16 which are arranged in a memory 14 and constitute a transmission means for transmitting multiplexed digital data are sequentially connected to a DIF encoder 13. I have. The driver 15 receives the DI input from the DIF encoder 13
The F packet is subjected to data transmission coding (channel coding) and output to the output terminal 16. The output terminal 16 is connected to a transmission line (not shown) constituted by a coaxial cable or an optical fiber cable, and multiplexed digital data is sequentially transmitted.

Here, the structure of the DIF packet generated by the DIF encoder 13 will be specifically described with reference to FIGS. FIG. 3 shows the DIF shown in FIG.
FIG. 3 is an explanatory diagram illustrating a configuration of a DIF packet generated by an encoder. As shown in FIG.
A DIF packet, which is a packet for transmitting a packet, has a packet header 100, two DIF blocks 101,
102, and parity 103 for error correction (in the figure, "EC
C "). Each of the DIF blocks 101 and 102 has a data amount of 80 words and has
This is the minimum unit block constituting the multiplexed DIF data 62 from the IF data multiplexer 11. Also, D
The IF encoder 13 adds a 7-word packet header 1 to the two generated DIF blocks 101 and 102.
An error correction parity 203 consisting of 00 and 4 words is added. As a result, one DIF packet is generated. After being packetized by the DIF encoder 13, the DIF packet is multiplexed on a transmission area provided in an effective video period of one frame period according to the SDI standard. Thereafter, encoding for data transmission is performed by the driver 15, and data obtained by multiplexing DIF packets according to the SDI standard is output from the output terminal 16 to the outside. still,
In the above description, the configuration in which the DIF encoder 13 performs the packetization process of generating the DIF packet has been described.
The IF encoder 13 may be configured to add the packet header 100 and the error correction parity 103.

Here, specific multiplex positions of the DIF flags 58 and 59 and specific multiplex positions of the transmission speed information 60 will be described with reference to FIGS. 4 and 5, respectively. FIG. 4 is an explanatory diagram showing the specific multiplexing positions of the DIF flags multiplexed by the DIF flag multiplexer shown in FIG. 2, and FIG. 5 is multiplexed by the DIF data multiplexer shown in FIG. FIG. 6 is an explanatory diagram showing specific multiplex positions of transmission speed information. In FIG. 4, each DIF flag 58,
59 is set and stored in all TF information columns of TF1 to TF3 of the fifth to seventh bytes of the header block of the DIF sequence, for example. The DIF sequence is a transmission unit defined by the DV format. When the data rate is 25 Mbps, one DIF sequence
The sequence corresponds to one track on the magnetic tape. In FIG. 5, the transmission speed information 60 is, for example, the fourth byte (PC) of the source control pack of the AAUX data.
It is set and stored in the SPEED information column of 3). As described above, in the digital data transmission apparatus of this embodiment, the DI
The F flags 58 and 59 and the transmission speed information 60 are respectively arranged at predetermined multiplex positions and transmitted together with digital data. As a result, in the transmission-side receiving device,
It becomes easy to detect the reproduction speed of the transmitted digital data and to appropriately reproduce it. Note that the configuration in which the DIF flag is created and set for each frame has been described.
A configuration in which a flag is created and set may be used. More specifically, three DIF flags respectively corresponding to audio data, video data, and subcode data included in the DIF sequence are created, and for example, TF1, TF
2 and TF3.

Hereinafter, the operation of the digital data transmission apparatus according to this embodiment will be specifically described with reference to FIG.
The description of the processing of the VAUX data, the AAUX data, and the subcode data multiplexed on the DIF data 62 will be omitted. First, the reproduction data 51, 52
Is read out from the hard disk device 1 on a frame basis and output to the reproduction data processors 2 and 3. The read operation in the hard disk device 1 is performed based on the read instruction information 61 from the system controller 12 according to a reproduction speed requested from the outside. Each of the reproduction data 51 and 52 is data for one frame, and is reproduced from the hard disk device 1 at the same time. The order of the reproduction data 51 and 52 on the time axis is the n-th and (n + 1) -th frames, respectively, where n is a natural number. Next, the reproduction data processors 2 and 3 respectively perform demodulation processing of the reproduction data 51 and 52 which are in a state of being modulated. Thereafter, the reproduction data processors 2 and 3 output the demodulated data to the connected error correction decoders 4 and 5, respectively. Subsequently, each of the error correction decoders 4 and 5 performs an error correction decoding process on the input data based on the error correction parity added at the time of recording, and stores the data as DIF data 53 and 54 in the memories 6 and 7. Each is written.

Next, in the memories 6, 7, the DIF flag multiplexers 9, 10, and the DIF data multiplexer 11, two-channel DIF data 53, 54 input in parallel are provided.
Is multiplexed into one processing system in channel units. After that, the DIF encoder 13
4, DIF packets of each channel 1 and 2 are arranged on a predetermined line according to the SDI standard with respect to the transmission area provided in 4. The multiplexing process and the arrangement of DIF packets are as follows.
This is performed according to the reproduction speed requested from outside. still,
In the following description, in order to clarify the operation and effect of the digital data transmission device of the present embodiment, the data transmission corresponding to the integral multiple speed reproduction speed is performed, and the reproduction speed other than the integral multiple speed is supported. The operation when data transmission is performed will be described.

First, with reference to FIGS. 6 and 7, the operation in the case of performing data transmission corresponding to an integral multiple speed reproduction speed, for example, a double speed reproduction speed, will be specifically described. FIG. 6 is a timing chart showing an operation of multiplexing one frame of DIF data in units of channels at the time of double speed reproduction in the digital data transmission apparatus shown in FIG.
FIG. 7 is an explanatory diagram showing a method of arranging two-channel DIF packets in an effective video period defined by the SDI standard at the time of double speed reproduction in the digital data transmission apparatus shown in FIG. In FIG. 6, DI for one frame
The F data 53 and 54 are written into the corresponding memories 6 and 7 at the same timing based on a write control signal 55 (FIG. 2) from the memory controller 8 (FIG. 2).
At the time of reading, these DIF data 53 and 54 need to be multiplexed sequentially from the channel 1 on the time axis. Therefore, the memory controller 8 first reads the DIF data 53 for one frame of channel 1 from the memory 6, and then reads the DIF data 54 for one frame of channel 2 from the memory 7. Therefore, the memory controller 8 sends the write control signal 55 to the memories 6 and 7.
Are output at the same timing. On the other hand, the memory controller 8
Outputs read control signals 56 and 57 (FIG. 2) to the memories 6 and 7 in accordance with the read positions of the DIF data 53 and 54 of the channels 1 and 2, respectively.

Subsequently, DIF data 53, 54 from memories 6, 7 to which DIF flag multiplexers 9, 10 are connected.
The corresponding DIF flags 58 and 59 from the system controller 12 (FIG. 2) are multiplexed,
Output to the data multiplexer 11. In detail, DIF
The flag multiplexer 9 receives, for example, the n-th frame from the memory 6. After that, the DIF flag multiplexer 9
The value “0” of the DIF flag 58 input from the system controller 12 is stored at the predetermined multiplex position in the n-th frame and output to the DIF data multiplexer 11. Similarly, the DIF flag multiplexer 10 receives, for example, the (n + 1) th frame from the memory 7. Then DIF
The flag multiplexer 10 stores the value “0” of the DIF flag 59 input from the system controller 12 at the predetermined multiplex position in the (n + 1) th frame, and outputs the value to the DIF data multiplexer 11.

Next, in the DIF data multiplexer 11, the DIF
One frame of data sequentially output from the IF flag multiplexers 9 and 10 is multiplexed on the time axis for each of channels 1 and 2 and output as one system of DIF data 62.
Since the multiplexing process is a time axis compression process for compressing the DIF data 53 and 54 of each channel 1 and 2 on the time axis, the multiplexing process is performed from the memories 6 and 7 to the DIF flag multiplexers 9 and 10. The read operation is performed at twice the frequency of the write operation. Subsequently, the DIF data 62 multiplexed by the DIF data multiplexer 11 is input to the DIF encoder 13 (FIG. 2). DIF encoder 13
Converts the input DIF data 62 into a packet, and adds a packet header as identification information of the packet, parity for error correction, and the like. Further, the DIF encoder 13
Acquires the requested reproduction speed (instructed transmission speed) from the transmission speed information 60 from the system controller 12.
The DIF encoder 13 performs 2 based on the playback speed.
Are provided in the memory 14 (FIG. 2),
DIF packets for each of the channels 1 and 2 are arranged on a predetermined standard line.

More specifically, as shown in FIG.
One frame period of a television signal specified by the I standard is divided into two transmission areas corresponding to channels 1 and 2 on a line basis based on a requested reproduction speed. That is, each transmission area of channels 1 and 2
A predetermined number of lines, for example, 94 lines are allocated. Specifically, as shown in FIG.
IF packets are arranged and multiplexed on lines 21 to 114. Similarly, DIF packets of channel 2 are arranged and multiplexed on lines 115 to 208. The number of DIF packets in each of channels 1 and 2 is 750 packets per frame. That is, the DIF data for one frame is generated by the DIF encoder 13 into 750 DIF packets.
These DIF packets are multiplexed by 8 packets per line, and are sequentially transmitted in a predetermined line unit. The arrangement of these DIF packets is performed by writing data to two transmission areas set in the memory 14 corresponding to each of the channels 1 and 2. In this way, the DIF packets of each of the channels 1 and 2 are time-division multiplexed and transmitted in line units. The lines for multiplexing the DIF packets of the channels 1 and 2 are not limited to those shown in FIG. 7, but can be set freely according to the application. For example, a line for channel 1 may be provided in the first field, and a line for channel 2 may be provided in the second field.

Next, reproduction speeds other than integral multiples, for example, 1.
The operation in the case of performing data transmission corresponding to the 5 × playback speed will be specifically described with reference to FIGS. In the following description, FIG.
The operation different from the operation at the double speed reproduction speed described with reference to FIG. 7 and FIG. 7 will be mainly described. FIG. 8 is a timing chart showing an operation of multiplexing one frame of DIF data on a channel basis at 1.5 × speed reproduction in the digital data transmission apparatus shown in FIG. FIG. 9 is a timing chart showing an example in which the digital data transmission apparatus shown in FIG.
FIG. 4 is an explanatory diagram showing a method for arranging DIF packets of a channel. As shown in FIG.
The IF data 53 and 54 are input in units of frames corresponding to the required 1.5 × playback speed. Specifically, as shown in the figure, for example, the n, (n + 2) and (n + 3) th frames are sequentially input to the memory 6 of the channel 1. For example, (n + 1), (n + 1), and (n)
The (+4) th frame is sequentially input. The order of the frames input to the memories 6 and 7 is determined by the system controller 12 (FIG. 2) in order to correspond to the required 1.5-times playback speed. 61 (FIG. 2) and instructed to the hard disk drive 1 (FIG. 2).

In the data transmission corresponding to the reproduction speed of 1.5 times, as shown in FIG. 8, the value of the DIF flag 58 of the channel 1 is always set to "0" and the value of the DIF flag of the channel 2 is set to "0".
In the IF flag 59, values of "1" and "0" are set alternately. The values of these DIF flags 58 and 59 are determined for each frame based on the requested 1.5 × speed, and are associated with the read instruction information 61 (frame order). More specifically, from the memory 7 to D
The same (n + 1) -th frame is output to the IF flag multiplexer 10 twice in succession. On the other hand, the DIF flag multiplexer 10
As the value of the flag 59, two consecutive values of "0" and "1"
It is output corresponding to each of the (n + 1) -th frames. The DIF flag multiplexer 10 multiplexes the values “0” and “1” of the DIF flag 59 into two (n + 1) th frames, respectively, and
1 sequentially. As a result, the one (n + 1) -th frame output earlier is multiplexed with the DIF flag 59 indicating that the data is valid and transmitted. On the other hand, in the (n + 1) -th frame indicated by the hatched portion in the figure, the DIF indicating that the data is invalid is displayed.
The flag 59 is multiplexed and transmitted. As a result, the receiving-side device at the transmission destination receives one of the previously transmitted (n
By recording or reproducing the +1) th frame, data processing including reproduction processing at the requested 1.5 times speed can be performed.

The DIF flags 58 and 59 are set to DIF data 5
After being multiplexed into the DIF encoders 3 and 54, the DIF data multiplexer 11 generates DIF data 62 multiplexed in channel units and outputs the DIF data 62 to the DIF encoder 13 (FIG. 2). As shown in FIG. 9, the DIF encoder 13 includes:
When performing data transmission corresponding to the quintuple playback speed, two transmission areas are provided in the memory 14 as in the case of the doubling speed shown in FIG. And DIF
The encoder 13 arranges DIF packets of each of the channels 1 and 2 in a corresponding transmission area on a line-by-line basis.
Note that the arrangement of the DIF packets shown in FIG. 9 is performed after all the DIF packets shown in FIG. 7 have been transmitted, and the (n + 1) -th frame indicated by the hatched portion in FIG. The case where the DIF packet is arranged in the transmission area of channel 2 is shown. As described above, in the digital data transmission apparatus of the present embodiment, when performing data transmission corresponding to a 1.5-times reproduction speed, for example, DIF packets of channels 1 and 2 are arranged in two transmission areas, respectively. . In the digital data transmission device of the present embodiment,
Using the DIF flags 58 and 59 created for each frame, the DIF packet of channel 1 is always transmitted as valid data, and the DIF packet of channel 2 is transmitted as valid data every two frames. Thus, in the digital data transmission apparatus of the present embodiment, 1.5
Data transmission corresponding to the double-speed reproduction speed can be performed to the device on the receiving side.

As described above, in the digital data transmission apparatus and transmission method of the present embodiment, the system controller 12 indicates that the digital data is valid data or invalid data based on the requested reproduction speed. DIF flags 58 and 59 are created for each frame. Further, in the digital data transmission device and the transmission method of the present embodiment,
The DIF encoder 13 provides at least one transmission area in an effective video period of one frame period based on the requested reproduction speed, and multiplexes and transmits the DIF data 53 and 54 including the DIF flags 58 and 59 described above. It is configured to Thus, in the digital data transmission apparatus and transmission method of the present embodiment, even when a reproduction speed other than the integer multiple speed is required, data transmission corresponding to the requested reproduction speed can be performed. Therefore, in the digital data transmission apparatus and the transmission method of the present embodiment, for example, when used for processing and editing processing of program material data,
By performing data transmission corresponding to a desired reproduction speed, it is possible to improve the content of a program in a receiving-side device, and to easily perform processing and editing processing of material data to make it more effective. . Further, in the digital data transmission device and the transmission method of the present embodiment, digital data can be transmitted at the maximum reproduction speed that can be supported by the receiving device, so that the transmission time in data transmission can be reduced, and Data processing time in the apparatus can be easily reduced.

<< Second Embodiment >> FIG. 10 shows a second embodiment of the present invention.
FIG. 2 is a block diagram illustrating a configuration of a digital data transmission device according to an embodiment of the present invention. In this embodiment, in the configuration of the digital data transmission apparatus, the DIF flag is output from the system controller to the DIF data multiplexer without providing the DIF flag multiplexer. Further, the transmission speed and the number of transmission areas are changed every frame period based on the requested reproduction speed. The other parts are the same as those of the first embodiment, and the duplicated description thereof will be omitted. In FIG. 10, in the digital data transmission apparatus of this embodiment, the DIF data multiplexer 21 inputs DIF data 53 and 54 from the memories 6 and 7 in units of frames. The DIF data multiplexer 21 receives the DIF flags 63 and 64 and the transmission speed information 65 from the system controller 22 and stores them at predetermined multiplex positions. As described above, in the digital data transmission apparatus of the present embodiment, the DIF flags 63, 64
Are multiplexed by the DIF data multiplexer 21, the DIF flag multiplexer can be omitted, and the configuration of the apparatus can be simplified as compared with the first embodiment. . Note that the DIF flags 63 and 64 are
As in the case of the third embodiment, the information is created for each frame in association with the read instruction information 66 for channels 1 and 2.

The digital data transmission apparatus of this embodiment differs from that of the first embodiment in that the system controller 22
Creates transmission speed information 65 for each frame period, which is a transmission unit, based on the requested reproduction speed. Thus, in the digital data transmission apparatus of the present embodiment, even when a reproduction speed other than the integer multiple speed is required, the DIF encoder 23 changes the transmission speed and the number of transmission areas every frame period based on the transmission speed information 65. Thus, data transmission corresponding to the above-described reproduction speed can be performed. Specifically, when the requested reproduction speed is V and the total number of transmission areas provided in L frame periods is M, the system controller 22 determines that the integer values M and L satisfy the equation V = M / L. And ask. Since the combination of these integer values M and L is infinite, the system controller 22 determines the value of M so as not to exceed the maximum number of transmission areas that can be provided in one frame period, and furthermore, The value of L that satisfies the above equation is determined. The system controller 22 allocates the determined M transmission areas in the determined L frame periods in integer units. Specifically, the system controller 22 adds integer values M1, M2 to L frame periods F1, F2,.
2,..., ML (M = M1 + M2 + --- + ML). The system controller 22 controls the DIF flag 63, so as to correspond to the transmission area allocated to each frame period.
64 is created for each frame, and transmission rate information 65 indicating the transmission rate is created for each frame period and output to the DIF data multiplexer 21 and the DIF encoder 23.
As a result, the DIF encoder 23 provides an integer number of transmission areas allocated to each of L frame periods, and
F packets can be arranged, and data transmission corresponding to the above-described reproduction speed can be performed.

More specifically, when a reproduction speed of 1.5 times is required, the system controller 22 sets the value of the set number L of frame periods and the total number M of transmission areas to, for example, two and three. Each is determined. System controller 22
Determines that two transmission areas are provided in one frame period of the two frame periods, and one transmission area is provided in the other frame period. The system controller 22 controls the DIF in the odd-numbered frame period, for example.
The value of the flags 63 and 64 is set to “0” to indicate, and the transmission speed information 65 indicates the double speed. In the even frame period, the system controller 22 sets the DI
One of the values of the F flags 63 and 64 is set to “0”, the other value is set to “1”, and the transmission speed information 65 is set.
Indicates a 1 × speed. As a result, the DIF
The encoder 23 provides two and one transmission areas in odd-numbered and even-numbered frame periods, respectively,
Place the packet. As a result, in the digital data transmission apparatus of the present embodiment, data transmission corresponding to the double speed and the normal speed is performed in the odd-numbered and even-numbered frame periods, respectively, and the data transmission corresponding to the required 1.5-time speed is performed. It can be performed.

The DIF encoder 23 receives the DIF data 67 multiplexed for each channel from the DIF data multiplexer 21 and converts the DIF data 67 into DIF data.
The flags 63 and 64 are extracted. Further, the DIF encoder 23 receives the transmission speed information 65 from the system controller 22. The DIF encoder 23 has a DIF flag 63,
A transmission area is provided in the memory 14 based on the transmission speed information 64 and the transmission speed information 65, and DIF packets are arranged. Specifically, when the transmission speed information 65 indicates, for example, a reproduction speed of 1 ×, the DIF encoder 23 provides one transmission area in the memory 14. Further, the DIF encoder 23 packetizes, inserts an ID, and transmits only the data of the frame indicated as valid data by the DIF flag among the DIF data 67 for two channels (for two frames). Place in the area. On the other hand, for data of a frame indicated as invalid data by the DIF flag, the DIF encoder 23
Does not perform data transmission by outputting to an area other than the transmission area without packetization.

Hereinafter, the operation of the digital data transmission apparatus according to the present embodiment will be described with reference to FIGS.
In the following description, a case where data transmission corresponding to a reproduction speed of 1.5 times is performed will be described for simplification of the description. FIG. 11 is a timing chart showing an operation of multiplexing one frame of DIF data in channel units in 1.5 × speed reproduction in the digital data transmission apparatus shown in FIG. FIG. 12 is a diagram showing the state of the digital data transmission apparatus shown in FIG.
One channel of D in the effective video period specified by the DI standard
FIG. 5 is an explanatory diagram showing a method for arranging IF packets. As shown in FIG. 11, DIF data 5
3, 54 are input in units of frames corresponding to the required 1.5 times playback speed. More specifically, as shown in FIG.
For example, the n, (n + 2), and (n + 3) th frames are sequentially input. In memory 7 of channel 2,
For example, (n + 1), (n + 1), and (n + 4) th frames are sequentially input. Note that the order of the frames input to the memories 6 and 7 is controlled by the system controller 22 (FIG. 1) in order to correspond to the required 1.5 × playback speed.
0) is determined, and is included in the read instruction information 66 (FIG. 10) and instructed to the hard disk device 1 (FIG. 10).

Next, the memories 6 and 7 store the DIF data 5
3 and 54 are output to the DIF data multiplexer 21 in frame units. This DIF data multiplexer 21
DIF flags 63 and 64 created for each frame are input from the system controller 22 (FIG. 10). The DIF data multiplexer 21 sets the DIF flags 63 and 64 to the corresponding DIF flags.
The IF data 53 and 54 are respectively stored at predetermined multiplexing positions, multiplexed in channel units, and output as one system of DIF data 67. In the DIF data 67, transmission speed information 65 (FIG. 10) from the system controller 22 created for each transmission unit is stored at a predetermined multiplex position. As shown in FIG. 11, when performing data transmission corresponding to a reproduction speed of 1.5 times speed, the digital data transmission apparatus of the present embodiment employs the DIF flag 63 of channel 1 as in the first embodiment. Is always set to a value of “0”, and the DIF flag 64 of channel 2 is set to “1” and “1”.
The values of these DIF flags 63 and 64 are determined for each frame based on the requested 1.5 × speed, and the read instruction information 6
6 (order of frames).

More specifically, in the odd-numbered frame period, the DIF data multiplexer 21 multiplexes the value “0” of the DIF flag 63 into the n-th frame from the memory 6 and (n + 1) from the memory 7. DIF on the に th frame
The value “0” of the flag 64 is multiplexed. Further, the DIF data multiplexer 21 arranges the n-th and (n + 1) -th frames obtained by multiplexing the DIF flags 63 and 64 in this order, and outputs them as DIF data 67 to the DIF encoder 23 (FIG. 10). After that, the DIF encoder 23 converts the DIF data 67
3, 64 are extracted, and transmission speed information 65 is received from the system controller 22. Then, the DIF encoder 23
Two transmission areas are provided in the memory 14 based on the transmission speed information 65. Further, the DIF encoder 23 has n
The DIF packet of the first frame is arranged in the transmission area of channel 1 in line units, and the DIF packet of the (n + 1) th frame is arranged in the transmission area of channel 2 in line units. As a result, as shown in FIG. 7, in the odd-numbered frame period, the DIF packets of the n-th and (n + 1) -th frames are arranged and transmitted in the transmission areas of the channels 1 and 2 in line units, respectively.

Subsequently, in the even-numbered frame period, D
The IF data multiplexer 21 receives the (n + 2)
The value “0” of the DIF flag 63 is multiplexed in the frame of interest, and the value “1” of the DIF flag 64 is multiplexed in the (n + 1) th frame (shown by hatching in the figure) from the memory 7. Further, the DIF data multiplexer 21 arranges the (n + 2) and (n + 1) th frames in which the DIF flags 63 and 64 are multiplexed, respectively, in this order, and
The data 67 is output to the DIF encoder 23 as data 67. Thereafter, the DIF encoder 23 extracts the DIF flags 63 and 64 from the input DIF data 67 and receives the transmission speed information 65 from the system controller 22. in this case,
On the other hand, the DIF flag 64 indicates that the data of the frame is invalid data, and the transmission speed information 65 indicates the 1x transmission speed. Therefore, the DIF encoder 23 provides one transmission area in the memory 14 and (n +
2) Only the data of the frame is determined to be valid data, and the DIF packet is generated. As a result, in the even-numbered frame period, as shown in FIG. 12, only the DIF packet of the (n + 2) -th frame is arranged and transmitted line by line in the transmission area of channel 1. As described above, in the digital data transmission apparatus of the present embodiment, two transmission areas corresponding to the double transmission speed are provided in the odd-numbered frame period, and the D frame for the two frames is provided.
An IF packet is being transmitted. Further, in the even-numbered frame period, one transmission area corresponding to the 1 × transmission speed is provided, and one frame of DIF packet is transmitted. As a result, the digital data transmission apparatus according to the present embodiment can perform data transmission corresponding to the reproduction speed of 1.5 times to the reception-side apparatus.

As described above, in the digital data transmission apparatus and transmission method of the present embodiment, the system controller 22 creates the transmission rate information 65 for each frame period based on the requested reproduction speed. Accordingly, in the digital data transmission apparatus and the transmission method according to the present embodiment, the transmission speed and the number of transmission areas are changed for each frame period so that the desired reproduction speed can be achieved without performing invalid frame data transmission. Data transmission can be performed. further,
In the digital data transmission apparatus and transmission method of the present embodiment, the DIF flag 63 created by the system controller 22
64 is output to the DIF data multiplexer 21 and multiplexed, so that the DIF flag multiplexer can be omitted, and the configuration can be simplified as compared with the first embodiment. it can.

<< Third Embodiment >> FIG. 13 shows a third embodiment of the present invention.
FIG. 2 is a block diagram illustrating a configuration of a digital data transmission device according to an embodiment of the present invention. In this embodiment, in the configuration of the digital data transmission apparatus, the line in the one frame period is divided into regions to provide a transmission region corresponding to the transmission speed indicated by the transmission speed information. The other parts are the same as those of the first embodiment, and the duplicated description thereof will be omitted. 13, in the digital data transmission apparatus of the present embodiment, the system controller 32 creates DIF flags 68 and 69, transmission speed information 70, and read instruction information 71 based on an externally requested reproduction speed. I have. The DIF flags 68 and 69 and the read instruction information 71 are created in the same manner as in the first embodiment, and output to the DIF flag multiplexers 9 and 10 and the hard disk device 1, respectively.

More specifically, in the digital data transmission apparatus of this embodiment, when two transmission areas corresponding to, for example, a double speed transmission rate are provided, the system controller 32 operates as follows.
Effective horizontal pixels (pixel numbers 0 to 143) included in the line
9) is divided into two, and the horizontal pixels of pixel numbers 0 to 719 are allocated to the transmission area of channel 1;
439 horizontal pixels are allocated to the transmission area of channel 2. The system controller 32 transmits the transmission speed information 70 to the DIF
The data is output to the data multiplexer 31 and the DIF encoder 33. As a result, in the digital data transmission apparatus of this embodiment, as will be described in detail later, the area within the line is divided, that is, the line of one frame period is divided in accordance with the transmission speed indicated by the transmission speed information 70. Digital data is arranged.

The DIF data multiplexer 31 performs time axis compression processing on the two-channel DIF data 53 and 54 from the DIF flag multiplexers 9 and 10 to perform one-channel DI
It is multiplexed into F data 72. In this time axis compression process,
Unlike the first and second embodiments, the DIF data 5
Reference numerals 3 and 54 are divided into a plurality of blocks corresponding to the above-described region division. Specifically, the DIF data multiplexer 31
Switches DIF data 53 and 54 input from the DIF flag multiplexers 9 and 10, respectively. This allows
DIF data 53, 5 divided into a plurality of blocks
4 are arranged as DIF data 72 and multiplexed.
As a result, in the digital data transmission device of this embodiment,
The DIF encoder 33 can easily arrange data in each transmission area. The DIF encoder 33 packetizes the input DIF data 72 and inserts an ID. The DIF encoder 33 provides a transmission area corresponding to the specified transmission speed in the memory 14 based on the transmission speed information 70, and arranges DIF packets. For details,
The DIF encoder 33 differs from the first and second embodiments in that two transmission areas obtained by dividing the line are provided in the memory 14 and the DIF packets of the channels 1 and 2 are stored in the corresponding transmission areas. Deploy.

Hereinafter, the operation of the digital data transmission apparatus according to this embodiment will be described. In the following description, the first
In order to facilitate comparison with the embodiment of the present invention, the case where data transmission corresponding to the double speed reproduction speed is performed, and 1.5
An operation in the case of performing data transmission corresponding to the double speed reproduction speed will be described. First, with reference to FIG. 14 and FIG. 15, an operation in the case of performing data transmission corresponding to a double speed reproduction speed will be specifically described. FIG.
FIG. 4 is a timing chart showing an operation of multiplexing one frame of DIF data on a channel basis at the time of double speed reproduction in the digital data transmission apparatus shown in FIG. FIG.
FIG. 14 is an explanatory diagram showing a method of arranging two-channel DIF packets in an effective video period specified by the SDI standard at the time of double speed reproduction in the digital data transmission device shown in FIG. In FIG. 14, DIFs from memories 36 and 37 to which DIF flag multiplexers 9 and 10 are connected are shown.
The system controller 32 (FIG. 1)
The corresponding DIF flags 68 and 69 from 3) are respectively multiplexed and output to the DIF data multiplexer 31. More specifically, the DIF flag multiplexer 9 receives, for example, the n-th frame from the memory 36. Thereafter, the DIF flag multiplexer 9 outputs the D signal input from the system controller 32.
The value “0” of the IF flag 68 is stored at the predetermined multiplex position in the n-th frame. Similarly, the DIF flag multiplexer 10 receives, for example, the (n + 1) th frame from the memory 37. Thereafter, the DIF flag multiplexer 10
Is the DIF flag 69 input from the system controller 32.
Is stored at the predetermined multiplex position in the (n + 1) th frame.

Next, the DIF data multiplexer 31 converts the DI
The DIF data 53 and 54 for one frame are input from the F flag multiplexers 9 and 10, respectively, and the DIF data 72 and
Multiplex. More specifically, the DIF data multiplexer 3
1 switches the connection with the DIF flag multiplexers 9 and 10 based on the transmission speed information 70 from the system controller 32, and inputs the DIF data 53 and 54. As a result, as shown in FIG.
The data is divided into a plurality of blocks and subjected to time axis compression processing that matches the transmission order.
The data is output from the F data multiplexer 31. Then, DIF
DIF data 7 multiplexed by data multiplexer 31
2 is input to the DIF encoder 33 (FIG. 13).
The DIF encoder 33 packetizes the input DIF data 72 and adds a packet header, which is identification information of the packet, a parity for error correction, and the like. further,
The DIF encoder 33 stores two transmission areas in the memory 1 based on the transmission speed information 70 from the system controller 32.
4 (FIG. 13), and DIF packets of channels 1 and 2 are arranged in their transmission areas.

More specifically, as shown in FIG.
The frame period is divided into two transmission areas corresponding to each of the channels 1 and 2. Furthermore, as shown in the figure, each transmission area is obtained by dividing the area within a line, and is assigned to each line by the number of 720 horizontal pixels. More specifically, as shown in FIG.
Lines and pixel numbers 0 to 719 on lines 284 to 367 are multiplexed. Similarly, the DIF packet of channel 2 has a pixel number 72 on lines 21 to 104 and lines 284 to 367.
0-1439 and multiplexed. In the above description, a case has been described in which all 1440 horizontal pixels included in the effective video period are allocated to two transmission areas according to the reproduction speed. However, the embodiment is not limited to this. For example, according to the data amount unit of the DIF packet,
A configuration in which 640 horizontal pixels are assigned to each transmission area may be employed.

Next, the operation in the case of performing data transmission corresponding to the 1.5-times reproduction speed will be described with reference to FIGS.
This will be specifically described with reference to FIG. In the following description, for simplification of the description, an operation different from the operation at the double speed reproduction speed described with reference to FIGS. 14 and 15 will be mainly described. FIG. 16 is a timing chart showing the operation of multiplexing one frame of DIF data in channel units at the time of 1.5 × speed reproduction in the digital data transmission apparatus shown in FIG. FIG. 17 is a timing chart showing the operation of the digital data transmission apparatus shown in FIG.
During the effective video period specified by the DI standard, D
FIG. 5 is an explanatory diagram showing a method for arranging IF packets. As shown in FIG. 16, the DIF data 53 and 54 are input to the memories 36 and 37 on a frame-by-frame basis corresponding to the requested 1.5-times playback speed. Specifically, as shown in the figure, for example, the n, (n + 2), and (n + 3) th frames are sequentially input to the memory 36 of channel 1. Channel 2 memory 37
Include (n + 1), (n + 1), and (n + 4)
The second frame is sequentially input. Each memory 3
The order of the frames input to the CPUs 6 and 37 is determined by the system controller 32 (FIG. 13) in order to correspond to the requested 1.5-times playback speed. ) Included in the hard disk drive 1
(FIG. 13).

In the data transmission corresponding to the reproduction speed of 1.5 times, as shown in FIG. 16, the value of the DIF flag 58 of the channel 1 is always set to "0", and the value of the DIF flag 59 of the channel 2 is set to "1". "" And "0" are set alternately. The values of these DIF flags 58 and 59 are
It is determined for each frame based on the requested 1.5 × speed, and is read instruction information 71 (frame order).
Associated with More specifically, the same (n + 1) -th frame is continuously output from the memory 37 to the DIF flag multiplexer 10 twice. On the other hand, the DIF flag multiplexer 10 is
The values of “0” and “1” are output as the value of the IF flag 59 corresponding to the two consecutive (n + 1) th frames, respectively. The DIF flag multiplexer 10 has a DIF
The values “0” and “1” of the flag 59 are multiplexed into two (n + 1) th frames, respectively, and are sequentially output to the DIF data multiplexer 31. As a result, the one (n + 1) -th frame output earlier is multiplexed with the DIF flag 59 indicating that the data is valid and transmitted. On the other hand, in the (n + 1) th frame shown by the hatched portion in the figure, D indicating that the data is invalid is shown.
The IF flag 59 is multiplexed and transmitted. as a result,
In the receiving device at the transmission destination, the DIF transmitted earlier
The (n + 1) -th frame in which the flag 59 is valid can be recorded or reproduced, and data processing including reproduction at the requested 1.5 times speed can be performed.

DIF flags 58 and 59 are set to DIF data 5
After multiplexing into the DIF data multiplexers 3 and 54, the DIF data multiplexer 31 transmits the transmission rate information 70 from the system controller 32.
Switch the connection with the DIF flag multiplexers 9 and 10 and input the DIF data 53 and 54. As a result, as shown in FIG.
The data is divided into a plurality of blocks and subjected to time axis compression processing that matches the transmission order.
F data multiplexer 31 to DIF encoder 33 (FIG. 1)
Output to 3). As shown in FIG. 17, when performing data transmission corresponding to a 1.5 × playback speed, the DIF encoder 33 performs area division within a line similarly to the case of the 2 × playback speed shown in FIG. Thus, two transmission areas are provided in the memory 14. Then, the DIF encoder 33 arranges the DIF packets of the respective channels 1 and 2 in the corresponding transmission areas. The DI shown in FIG.
The arrangement of the F packets is performed after all the DIF packets shown in FIG. 15 have been transmitted.
6, the DIF of the (n + 1) th frame indicated by the shaded portion
The case where a packet is arranged in the transmission area of channel 2 is shown. As described above, in the digital data transmission apparatus of the present embodiment, when performing data transmission corresponding to a 1.5-times reproduction speed, for example, DIF packets of channels 1 and 2 are arranged in two transmission areas, respectively. . In the digital data transmission apparatus of this embodiment, the channel 1 is used by using the DIF flags 58 and 59 created for each frame.
Are always transmitted as valid data, and the DIF packet of channel 2 is transmitted as valid data every two frames. As a result, the digital data transmission apparatus according to the present embodiment can perform data transmission corresponding to the reproduction speed of 1.5 times to the reception-side apparatus.

As described above, in the digital data transmission apparatus and transmission method of the present embodiment, the system controller 32 indicates that the digital data is valid data or invalid data based on the requested reproduction speed. DIF flags 58 and 59 are created for each frame. Further, in the digital data transmission device and the transmission method of the present embodiment,
The DIF encoder 33 multiplexes the DIF data 53 and 54 including the DIF flags 58 and 59 into each transmission area obtained by dividing the area of the line based on the transmission rate specified by the transmission rate information 70. It is configured to transmit. Thus, in the digital data transmission apparatus and transmission method of the present embodiment, even when a reproduction speed other than the integer multiple speed is required, data transmission corresponding to the requested reproduction speed can be performed. Further, in the digital data transmission apparatus and the transmission method of the present embodiment, each of the memories 36, 3
7 is configured to sequentially output the input DIF data for one frame, so that their storage capacities may be any as long as they can hold the DIF data for one frame.
Further, the retention period in each memory can be shortened.
As a result, in the digital data transmission apparatus and the transmission method of the present embodiment, the size of the memory can be made smaller than that of the first and second embodiments, and the delay time in the memory can be reduced. it can. In addition to the above description, the DIF flag multiplexer is omitted and the DIF flag from the system controller is output to the DIF data multiplexer in the same manner as the flag of the second embodiment. Alternatively, the system controller may be configured to create the transmission rate information every frame period.

In the description of each of the above embodiments, 525 /
Although the configuration in which digital data compressed during the effective video period of the 60-system television signal is multiplexed and transmitted has been described, the embodiment is not limited thereto.
Digital data compressed during the effective video period of a 625/60 television signal may be multiplexed and transmitted. Also, a configuration has been described in which the multiplexed video signal is output during an effective video period of one frame period according to the SDI standard.
PTE-305 standard, that is, SDTI (Serial Data Transpo
(rt Interface) Digital data may be multiplexed and output during an effective video period of one frame period according to the standard. In the description of each of the above embodiments, the configuration in which digital data stored in the hard disk device is reproduced by the output system of two channels and multiplexed with the DIF flag has been described. Any configuration that reproduces and multiplexes with the DIF flag may be used. For example, digital data stored in a disk-shaped recording medium such as a magnetic tape or an optical disk may be reproduced by a 4-channel output system and multiplexed with a DIF flag.

The digital data to be transmitted is D
The data is not limited to data compressed based on the V format, but may be data compressed by another high efficiency coding technique. According to the digital data transmission apparatus and the transmission method of the present invention, data compressed based on, for example, the MPEG standard can be transmitted in the same manner. Also,
Although the configuration in which the memory controller outputs the write instruction signal and the read instruction signal to the memory has been described, the system controller may generate these instruction signals based on the requested reproduction speed and output the signals to the memory. Good. With this configuration, the memory controller can be omitted. Further, since any of the digital data transmission methods in the above-described embodiments can be computer-programmed, a computer-executable recording medium can provide the transmission method of the present invention. Here, the recording medium is a data recording device including a floppy disk, a CD-ROM, a DVD, a magneto-optical disk, a removable hard disk, and a flash memory.

[0063]

As described above, in the digital data transmission apparatus and transmission method of the present invention, the flag creation means indicates that the digital data is valid data or invalid data based on the requested reproduction speed. Flags are created for each frame. Further, in the digital data transmission apparatus and the transmission method according to the present invention, the multiplexing means provides at least one transmission area in the effective video period of one frame period based on the requested reproduction speed, and includes the flag. Digital data is multiplexed and transmitted. Thus, the digital data transmission apparatus and transmission method of the present invention can perform data transmission corresponding to the requested reproduction speed even when a reproduction speed other than the integral multiple speed is required. Therefore, according to the digital data transmission apparatus and transmission method of the present invention, for example, when used for processing and editing of material data for a program, the data transmission corresponding to a desired reproduction speed is performed so that the program on the reception side apparatus is transmitted. It is possible to easily process and edit the material data for improving the content and making the content data more effective. Further, in the digital data transmission device and the transmission method of the present invention, digital data can be transmitted at the maximum reproduction speed that can be supported by the receiving device, so that the transmission time in data transmission can be reduced and the receiving device can be transmitted. , The data processing time can be easily reduced. Further, since the transmission method of the present invention can be made into a computer program, the above-described data transmission can be performed by recording the transmission method of the present invention on a computer-readable recording medium.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram showing a configuration of one frame in the SDI standard.

FIG. 2 is a block diagram showing a configuration of a digital data transmission device according to a first embodiment of the present invention.

FIG. 3 is an explanatory diagram showing a configuration of a DIF packet generated by the DIF encoder shown in FIG.

FIG. 4 is an explanatory diagram showing specific multiplexing positions of DIF flags multiplexed by the DIF flag multiplexer shown in FIG. 2;

FIG. 5 is an explanatory diagram showing specific multiplex positions of transmission speed information multiplexed by the DIF data multiplexer shown in FIG. 2;

FIG. 6 is a timing chart showing an operation of multiplexing one frame of DIF data in channel units at the time of double speed reproduction in the digital data transmission apparatus shown in FIG. 2;

FIG. 7 is an explanatory diagram showing a method of arranging two-channel DIF packets in an effective video period specified by the SDI standard at the time of double speed reproduction in the digital data transmission device shown in FIG. 2;

8 is a timing chart showing an operation of multiplexing one frame of DIF data on a channel basis at 1.5 × speed reproduction in the digital data transmission apparatus shown in FIG. 2;

FIG. 9 is an explanatory diagram showing a method of arranging two-channel DIF packets in an effective video period defined by the SDI standard at 1.5 × speed reproduction in the digital data transmission device shown in FIG. 2;

FIG. 10 is a block diagram showing a configuration of a digital data transmission device according to a second embodiment of the present invention.

11 is a timing chart showing an operation of multiplexing one frame of DIF data on a channel basis at 1.5 × speed reproduction in the digital data transmission apparatus shown in FIG. 10;

FIG. 12 is an explanatory diagram showing a method of arranging a DIF packet of one channel in an effective video period specified by the SDI standard at 1.5 × speed reproduction in the digital data transmission device shown in FIG.

FIG. 13 is a block diagram showing a configuration of a digital data transmission device according to a third embodiment of the present invention.

14 is a timing chart showing an operation of multiplexing one frame of DIF data on a channel basis at the time of double speed reproduction in the digital data transmission apparatus shown in FIG.

15 is an explanatory diagram showing a method of arranging two-channel DIF packets in an effective video period defined by the SDI standard at the time of double speed reproduction in the digital data transmission device shown in FIG.

16 is a timing chart showing an operation of multiplexing one frame of DIF data in channel units in 1.5 × speed reproduction in the digital data transmission apparatus shown in FIG. 13;

FIG. 17 is an explanatory diagram showing a method of arranging two-channel DIF packets in an effective video period specified by the SDI standard at 1.5 × speed reproduction in the digital data transmission apparatus shown in FIG. 13;

FIG. 18 is a block diagram showing a configuration of a conventional digital data transmission device.

FIG. 19 is an explanatory diagram showing a method of arranging four-channel DIF packets in an effective video period of one frame specified by the SDI standard in the conventional digital data transmission device shown in FIG. 18;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Hard disk drive 2, 3 Reproduction data processor 4, 5 Error correction encoder 6, 7, 14, 36, 37 Memory 8 Memory controller 9, 10 DIF flag multiplexer 11, 21, 31 DIF data multiplexer 12, 22, 32 System controller 13, 23, 33 DIF encoder 15 Driver

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Masatoshi Taniguchi 1006 Kadoma Kadoma, Osaka Prefecture Matsushita Electric Industrial Co., Ltd. F term (reference) 5C053 FA23 GA08 GB06 GB11 GB15 GB17 GB21 GB40 HA24 HA33 JA30 KA01 KA24 5C063 AB03 AB07 AC01 AC05 AC10 CA11 CA16 CA38 DA05 DA07 DA13 5D044 AB05 AB07 BC01 CC04 DE03 DE14 FG10 FG23 HL11

Claims (27)

[Claims] 1. A digital data transmission apparatus for multiplexing and transmitting digital data during one frame period of a television signal, comprising: reproducing means for reproducing digital data at an externally requested reproduction speed; Flag generating means for generating a flag indicating that digital data reproduced by the reproducing means is valid data or invalid data for each frame, and at least one transmission based on the reproducing speed. Multiplexing means for providing an area in the one frame period, multiplexing a flag created by the flag creating means with digital data from the reproducing means, and arranging the multiplexed digital data in the transmission area; Transmitting means for transmitting digital data multiplexed by the multiplexing means; Using grayed and configured to perform data transmission corresponding to said playback speed, the digital data transmission apparatus, characterized in that. 2. The apparatus according to claim 1, wherein said multiplexing means is configured to provide said transmission area in units of lines.
2. A digital data transmission device according to claim 1. 3. The reproduction speed is pq times speed (p and q are 1 and 2).
Multiplexing means is (p + 1)
2. The digital data transmission device according to claim 1, wherein a plurality of transmission areas are provided in said one frame period. 4. A digital data transmission apparatus for multiplexing and transmitting digital data during one frame period of a television signal, comprising: reproducing means for reproducing digital data at a reproduction speed requested from outside; A flag generating means for generating a flag indicating that digital data reproduced by the reproducing means is valid data or invalid data for each frame based on the reproducing speed; Multiplexing means for changing the number of transmission areas and transmission speed, multiplexing the flag created by the flag creation means with digital data from the reproduction means, and arranging the multiplexed digital data in the transmission area. And transmission means for transmitting the digital data multiplexed by the multiplexing means, Using the serial flag was configured to perform data transmission corresponding to the reproduction speed, the digital data transmission apparatus, characterized in that. 5. When the playback speed is V and the total number of transmission areas provided in L frame periods is M, the flag creation means satisfies the formula V = M / L and the one frame period The value of M is determined so as not to exceed the maximum number of transmission areas that can be provided in the frame, and the value of L that satisfies the above equation is determined. 5. The digital data transmission device according to claim 4, wherein the region is allocated in integer units, and wherein the multiplexing unit is configured to provide a transmission region allocated to each of L frame periods. 6. The multiplexing means according to claim 4, wherein only digital data of a frame indicated by the flag as valid data is arranged in the transmission area. 2. A digital data transmission device according to claim 1. 7. The apparatus according to claim 1, wherein said multiplexing means divides a line in said one frame period into a transmission area corresponding to said reproduction speed.
Or the digital data transmission device according to 4. 8. The digital data transmission apparatus according to claim 1, wherein said digital data includes at least video data encoded at a high efficiency. 9. The high-efficiency encoded video data includes:
9. The digital data transmission device according to claim 8, wherein the data is data which has been highly efficiently coded at a data rate of 25 Mbps in one frame unit. 10. A digital data transmission method for multiplexing and transmitting digital data during one frame period of a television signal, comprising: a reproducing step of reproducing digital data at a reproduction speed requested from outside; A creation step of creating, for each frame, a flag indicating that the digital data to be played back in the playback step is valid data or invalid data, based on the speed; and at least one transmission based on the playback speed. A multiplexing step of providing an area in the one frame period, multiplexing the flag created in the creating step with the digital data reproduced in the reproducing step, and arranging the multiplexed digital data in the transmission area; Using the flag created in the step, data transmission corresponding to the reproduction speed Method for transmitting digital data comprising: the transmission step of performing, the. 11. The transmission method according to claim 1, wherein in the multiplexing step, the transmission area is provided for each line.
0. A method for transmitting digital data according to item 0. 12. In the multiplexing step, when the reproduction speed is pq speed (p and q are integers of 1 to 9), (p + 1) transmission areas are provided in the one frame period. The method of transmitting digital data according to claim 10, wherein: 13. A digital data transmission method for multiplexing and transmitting digital data during one frame period of a television signal, comprising: a reproducing step of reproducing digital data at a reproduction speed requested from outside; A creation step of creating, for each frame, a flag indicating that the digital data to be played back in the playback step is valid data or invalid data, based on the speed, and for each frame period based on the playback speed, A multiplexing step of changing the number and transmission speed of the transmission areas, further multiplexing the flag created in the creation step with the digital data reproduced in the reproduction step, and placing the multiplexed digital data in the transmission area. Using the flag created in the creation step, the data corresponding to the playback speed is used. Method for transmitting digital data comprising: the transmission step of performing data transmission, a. 14. Assuming that the reproduction speed is V and the total number of transmission areas provided in L frame periods is M, the expression V = M / L can be satisfied and the transmission region can be provided in the one frame period. The value of M is determined so as not to exceed the maximum number of transmission areas, and the value of L is further determined so as to satisfy the above equation. The total number of M divided into integer units in each of L frame periods is M 14. A transmission area is provided.
2. A method for transmitting digital data according to item 1. 15. The multiplexing step according to claim 13, wherein only digital data of a frame indicated by the flag as valid data is arranged in the transmission area. A method for transmitting digital data. 16. In the multiplexing step, the 1
2. A transmission area corresponding to the reproduction speed is provided by dividing a line in a frame period into areas.
14. The digital data transmission method according to 0 or 13. 17. The digital data transmission method according to claim 10, wherein the digital data includes at least video data encoded at a high efficiency. 18. The digital data transmission according to claim 17, wherein said highly efficient encoded video data is data which is highly efficient encoded at a data rate of 25 Mbps in one frame unit. Method. 19. Reproducing digital data at a reproduction speed requested from outside, and setting a flag indicating that the digital data to be reproduced is valid data or invalid data for each frame based on the reproduction speed. Creating, based on the playback speed, providing at least one transmission area in one frame period of a television signal, multiplexing the created flag with the reproduced digital data, and combining the multiplexed digital data with the reproduced digital data. A recording medium recording a transmission program, comprising: arranging in a transmission area; and performing data transmission corresponding to the reproduction speed by using a created flag. 20. The recording medium according to claim 19, wherein said transmission area is provided for each line. 21. When the reproduction speed is pq speed (p and q are integers of 1 to 9), (p + 1) transmission areas are provided in the one frame period.
10. A recording medium on which the transmission program according to 9 is recorded. 22. Reproducing digital data at a reproduction speed requested from the outside; and, for each frame, a flag indicating that the digital data to be reproduced is valid data or invalid data based on the reproduction speed. Creating, based on the playback speed, changing the number of transmission areas and the transmission speed for each frame period of a television signal, further multiplexing the created flag with the reproduced digital data, and multiplexing the multiplexed digital data. A recording medium storing a transmission program, comprising: arranging data in the transmission area; and performing data transmission corresponding to the reproduction speed by using a created flag. 23. Assuming that the reproduction speed is V and the total number of transmission areas provided in L frame periods is M, the expression V = M / L can be satisfied and the transmission region can be provided in the one frame period. The value of M is determined so as not to exceed the maximum number of transmission areas, and the value of L is determined so as to satisfy the above formula. The total number of M divided into integer units in each of L frame periods is M 23. A transmission area is provided.
A recording medium on which the transmission program according to item 1 is recorded. 24. The recording according to claim 22, wherein only digital data of a frame indicated by the flag as valid data is arranged in the transmission area. Medium. 25. The recording medium according to claim 19, wherein a transmission area corresponding to the reproduction speed is provided by dividing a line in the one frame period into areas. 26. The recording medium according to claim 19, wherein said digital data includes at least video data encoded with high efficiency. 27. The transmission program according to claim 26, wherein said highly efficient encoded video data is data which is highly efficient encoded at a data rate of 25 Mbps per frame. Recording medium.