JP2002290971A - Transcoder system, processing method therefor and program therefor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a transcoder system, in which time for re-encoding processing is shortened by suppressing a picture quality deterioration to occur in the case of re-encoding to a minimum, and a processing method therefor and a program therefor. SOLUTION: By transferring encoded parameter data which are used for decoding in a decoder 1, to an encoder 2 before decoded digital video data, in the case of re-encoding in the encoder 2, the encoding processing of the inputted digital video data, can be started in the order of inputting so that time for re-encoding processing can be shortened. Further, in the case of transfer, the encoded parameter data are multiplexed by utilizing an idle slot on a transmission line from the decoder 1 to the encoder 2 so that a conventional transmitting method can be utilized as it is.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a transcoder system for transcoding digital broadcast signals, a processing method therefor, and a program therefor, which minimizes image degradation when re-encoding a decoded digital broadcast signal. The present invention relates to a transcoder system, a processing method thereof, and a program thereof.

[0002]

2. Description of the Related Art Recently, digital broadcasting has started, video data has been digitized, and coded video data has been edited or recorded at a broadcasting station or at home.
Transcoder systems have been developed in which data is decoded and then re-encoded. As such a transcoder system, a system that minimizes image quality degradation during re-encoding is demanded. For example, a conventional example that suppresses image quality degradation is disclosed in JP-A-2000-59784. "Encoding device and method, and providing medium".

In the above-mentioned conventional example, the current encoding parameter and a plurality of generations of encoding parameters supplied by a history decoding device are multiplexed with video data supplied by a decoding device and output to the encoding device. The video data is coded by selecting an optimum coding parameter on the device side, thereby minimizing the image quality deterioration at the time of re-coding.

FIG. 7 is a block diagram showing a schematic configuration of a conventional transcoder system. As shown in FIG.
The conventional transcoder system includes a decoding device 71 and an encoding device 72. The decoding device 71
The video data is decoded with reference to the encoding parameter data from the input bit stream, and the digital video data is output to the encoding device 72. Encoding device 72
Is based on the digital video data from the decoding device 71,
The encoding device 7 performs the encoding process and the operation according to the MPEG2 standard, and also generates the parameter data in the encoding.
Perform in 2.

FIG. 8 is a plan view showing a transmission format in a conventional transcoder system. As shown in FIG. 8, for example, for a 10-bit transmission path of the HDI standard, digital video data is assigned to upper 8 bits, and “00” is output as lower 2 bits.

[0006]

However, in the above-mentioned conventional example, if all the video data and all the encoding parameter data are not transferred from the decoding device to the encoding device, the re-encoding process on the encoding device side is required. There is a problem that can not be.

Also, since the video data and the encoding parameters are transmitted to the encoding device at the same time, it takes time for the encoding device to once separate and then perform re-encoding. There is a problem that the encoding process takes time.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems, and a transformer for minimizing image quality degradation that occurs at the time of re-encoding and reducing the time required for video data encoding processing. An object of the present invention is to provide a coder system, a processing method thereof, and a program thereof.

[0009]

According to an aspect of the present invention, there is provided a transcoder system comprising a decoding device and an encoding device, wherein the decoding device includes a receiving device. Decoding means for decoding the converted digital signal to generate digital video data, extracting means for extracting parameter data used in decoding the digital signal by the decoding means, and multiplexing the digital video data and the parameter data. Multiplexing means for multiplexing the parameter data by shifting the parameter data at least one frame earlier, and transfer means for transferring the multiplexed data multiplexed by the multiplexing means to an encoding device. And

[0010] According to a second aspect of the present invention, in the first aspect of the present invention, the encoding apparatus further comprises: a separating unit for separating the multiplexed data transferred by the transferring unit into digital video data and parameter data; Encoding means for encoding digital video data based on the parameter data separated by the above.

According to a third aspect of the present invention, in the second aspect of the present invention, the encoding device has storage means for storing the parameter data separated by the separation means, and the coding means stores the parameter data in the storage means. The digital video data is encoded based on the parameter data obtained.

According to a fourth aspect of the present invention, there is provided a method for processing a transcoder system comprising a decoding device and an encoding device, comprising the steps of: decoding a received digital signal to generate digital video data; Extracting the parameter data used in decoding the digital signal by the decoding step; and multiplexing the digital video data and the parameter data by shifting the parameter data at least one frame before. Multiplexing step, a transfer step of transferring the multiplexed data multiplexed by the multiplexing step to the encoding device, and a separation of separating the multiplexed data transferred by the transfer step into digital video data and parameter data. Step and the parameter data separated by the separation step. And having a coding step of encoding the digital video data.

According to a fifth aspect of the present invention, in accordance with the fourth aspect of the present invention, there is provided a storage step for storing the parameter data separated by the separation step, and the encoding step includes the step of storing the parameter data stored in the storage step. The digital video data is encoded based on the digital video data.

According to a sixth aspect of the present invention, there is provided a program for a transcoder system including a decoding device and an encoding device, wherein the decoding device decodes a received digital signal to generate digital video data. Decoding processing, extracting processing for extracting parameter data used when decoding a digital signal by decoding processing, and, when multiplexing digital video data and parameter data, setting the parameter data at least one frame earlier. And a transfer process of transferring the multiplexed data multiplexed by the multiplexing process to the encoding device.

According to a seventh aspect of the present invention, in the invention of the sixth aspect, a separation process for separating the multiplexed data transferred by the transfer process into digital video data and parameter data by the encoding device, and a separation process And encoding processing for encoding digital video data based on the parameter data separated by the above.

According to an eighth aspect of the present invention, in accordance with the seventh aspect of the present invention, the encoding device is configured to execute a storing process of storing the parameter data separated by the separating process in the memory, and the coding process includes the storing process. Encoding digital video data based on parameter data stored in a memory.

According to a ninth aspect of the present invention, there is provided a program for a transcoder system including a decoding device and an encoding device, wherein the decoding device decodes a received digital signal to generate digital video data. Decoding processing, extracting processing for extracting parameter data used when decoding a digital signal by decoding processing, and, when multiplexing digital video data and parameter data, setting the parameter data at least one frame earlier. And multiplexing data transferred by the multiplexing process, and multiplexing data transferred by the multiplexing process to the encoding device. Separation processing for separating data into digital video data and parameter data, and parameter data separated by the separation processing Encoding process and encoding digital video data based, characterized in that for the execution.

According to a tenth aspect of the present invention, in the ninth aspect of the present invention, the encoding device executes a storing process of storing the parameter data separated by the separating process in the memory, and the encoding process is performed by the storing process. Encoding digital video data based on parameter data stored in a memory.

<Operation> According to the present invention, in a decoding device for decoding input bit stream data, encoding parameter data used for decoding video data is extracted, and video data and encoding parameter data are multiplexed. When converting to a format, the format is such that parameter data is inserted into an empty slot on the transmission line format for transmitting video data. At this time, the video data and the encoding parameter data used for decoding the video data are not multiplexed in the same frame but are multiplexed and output to a frame one or more frames earlier than the video data. . Prior to the input of the video data to be encoded, the encoding device has already received the encoding parameter data one or more frames earlier, and thus executes the encoding process while receiving the video data.

[0020]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a block diagram of a transcoder system according to an embodiment of the present invention. 1 to 6 show an embodiment of a transcoder system, a processing method thereof, and a program thereof according to the present invention.

<First Embodiment> FIG. 1 shows a first embodiment of the present invention.
It is a block diagram showing a schematic structure of a transcoder system which is an embodiment. In FIG. 1, a transcoder system according to an embodiment of the present invention includes a decoding device 1,
And an encoding device 2.

The decoding device 1 includes a decoding unit 11 and a multiplexing unit 12. The decoding unit 11 decodes the input bit stream data to generate digital video data, and at the same time, extracts the encoding parameter data included in the bit stream used at the time of decoding. The multiplexing unit 12 multiplexes the digital video data decoded by the decoding unit 11 and the coding parameters used at the time of decoding, and outputs the multiplexed data to the transmission path.

The encoding device 2 includes a separation unit 21 and an encoding unit 22. The separation unit 21 separates the digital video data output from the multiplexing unit 12 received via the transmission path into digital video data and coding parameter data superimposed on the digital video data. The encoding unit 22 encodes the digital video data while referring to the encoding parameter data separated by the separation unit 21, and outputs the digital video data as bit stream data.

FIG. 2 is a block diagram showing the internal configuration of the decoding device according to the first embodiment of the present invention. 2, the decoding device includes a TS filter 111, a video decoding circuit 112, a variable length decoding circuit 113, and a multiplexing circuit 114.

The TS filter 111 extracts a PES signal for outputting to the video decoding circuit 112 and an ES signal for outputting to the variable length decoding circuit 113 from the input bit stream data, and performs video decoding. To the decoding circuit 112 and the variable length decoding circuit 113, respectively.

The video decoding circuit 112 decodes the PES signal input from the TS filter 111 into digital video data, and converts the 8-bit digital video data of the Y signal and the digital video data of the 8-bit C signal into digital video data, respectively. Output to the multiplexing circuit 114.

The variable length decoding circuit 113 extracts coding parameter data from the bit stream data based on the ES signal input from the TS filter 111,
The data is output to the multiplexing circuit 114 in an 8-bit data format.

The multiplexing circuit 114 is a video decoding circuit 1
The 8-bit encoding parameter data output from the variable-length decoding circuit 113 is multiplexed with the 8-bit digital video data of the Y signal and the digital video data of the 8-bit C signal output from Outputs data to the transmission path. This transmission line is a transmission line of the SDI / HDI standard generally used.

FIG. 3 is a block diagram showing the internal configuration of the encoding device according to the first embodiment of the present invention. In FIG. 3, the encoding device includes a demultiplexing circuit 211, a video encoding circuit 212, and an encoding control circuit 213.

The separating circuit 211 converts the digital video data on which the input encoding parameter data is superimposed,
Digital video data and encoding parameter data are separated and the digital video data is
To the encoding control circuit 213.

The video encoding circuit 212 encodes the input digital video data into a bit stream format. At the time of the encoding, the video encoding circuit 212 refers to the encoding parameter data input from the encoding control circuit 213. Encode.

The encoding control circuit 213 comprises
The encoding parameter data inputted from 1 is inputted when the encoding circuit 212 encodes digital video data.

FIG. 4 is a plan view showing a multiplexing format example in the multiplexing circuit according to the first embodiment of the present invention. As shown in FIG. 4, when multiplexing digital video data and coding parameters, the format is such that the coding parameters are superimposed on the vacant slots of the transmission path. That is, digital video data and encoding parameter data are multiplexed and transmitted in one frame of data.

In FIG. 4, it is assumed that data is transmitted in order from the left side. For example, in the first frame (during a blanking period), the first frame used when decoding the first digital video data (1) is used. Encoding parameter data (1)
Only transmit. Next, while transmitting the first frame, the second digital video data (1) and the second digital video data (2) used when decoding the digital video data (2) are used.
In the format (data of the first frame) to be multiplexed and transmitted.

The encoding parameter data superimposed on the digital video data of the first frame and thereafter is shifted by one frame before the encoding parameter data as described above.
That is, the configuration is such that the encoding parameters are transmitted first.

In the last frame (n-th frame data), only digital video data (n) is transmitted, and encoding parameter data is transmitted without being superimposed.

Here, regarding the possibility that the encoding parameter data can be sent before the decoded digital video data, the data amount of the encoding parameter is about one fifth of the digital video data amount. Even if one parameter data is sent for two dots, all the parameter data can be sent while one frame of digital video data is being output.

Further, although it is necessary for the decoding device to perform the decoding processing of the digital video data, since the encoding parameter data is only taken out, the encoding parameter is output earlier in terms of the processing amount. It is possible.

With reference to FIG. 5, a method of superimposing encoding parameter data in multiplexing will be described. The method of superimposing the encoding parameter data is as shown in FIG. Here, a description will be given of a method of superimposing a commonly used HDI standard 10-bit transmission path.

In the 10-bit transmission line, the 8-bit digital video data output from the video decoding circuit 112 is directly assigned to the upper 8 bits. The encoding parameter data is assigned to the lower 2 bits. At this time, since the encoding parameter data length is in units of 8 bits,
The data is divided into four data by two bits, and is divided into two dots of digital video data of Y signal and two dots of digital video data of C signal. That is, in the case of totaling, when transmitting data of two dots of digital video data, a method of transmitting one encoding parameter data is used.

In the above example, the encoding parameter data is transmitted one frame ahead of the digital video data. However, the encoding parameter data is in a format that can be transmitted two frames or more.

At this time, the time difference between the decoding time of the video decoding circuit 112 of the decoding apparatus 1 and the operation of each of the tunable decoding circuits 113 for the coding parameter data is determined by converting the coding parameter data into digital video data. This is the number of frames that can be sent beforehand. On the other hand, the encoding device 2 needs a buffer for saving the encoding parameter data sent earlier than the digital video data, and the buffer amount is only required to save the time difference data described above. Requires buffer space.

More specifically, as described with reference to FIG.
The video data is decoded by the video decoding circuit 112.
The extraction of the encoding parameter data is performed by the variable length decoding circuit 11.
Since the processing is performed by another circuit, such as processing in step 3, the processing time is different not only in the data amount but also in the processing. From this, the time at which the output of the two data starts is also different, and the encoding parameter data output from the decoding device 1 is output three frames earlier than the digital video data. The encoding device 2 has a buffer for saving encoding parameter data for three frames or, if necessary, for four frames.

<Second Embodiment> FIG. 6 shows a second embodiment of the present invention.
It is a block diagram showing a schematic structure of a transcoder system which is an embodiment. The second embodiment of the present invention is different from the first embodiment in a configuration in which a buffer for saving parameter data as described above is provided in the encoding device.

A parameter buffer 23 is formed in the code unit 22 in the coding device 2. As described above, for example, encoding parameters for three frames or four frames are saved in the parameter buffer 23, and when digital video data is input later, the encoding parameters saved in the parameter buffer 23 are saved. The encoding process is performed by using this.

In the configuration of each of the above-described embodiments, each of the above-described devices is controlled by a data processing circuit (CPU) (not shown) reading a control program stored in a ROM or the like.

The embodiments described above are preferred embodiments of the present invention, and can be variously modified and implemented without departing from the gist of the present invention.

[0048]

As is apparent from the above description, according to the present invention, when the encoding parameter data used for decoding the digital video data by the decoding device is transmitted to the encoding device, the digital video data is transmitted to the encoding device. By transmitting the data before transmitting the data, the digital video data can be received and the encoding process can be performed immediately, and the time required for the re-encoding process can be reduced.

According to the present invention, when multiplexing and transmitting, coded parameter data is inserted into an empty slot on a transmission line format for transmitting video data, so that a conventional transmission line can be used as it is. Can be.

Further, according to the present invention, since the encoding apparatus receives the encoding parameter data prior to the input of the digital video data, the inputted digital video data is encoded sequentially from the encodeable digital video data. Can be performed.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating a schematic configuration of a transcoder system according to a first embodiment of the present invention.

FIG. 2 is a block diagram illustrating an internal configuration of a decoding device.

FIG. 3 is a block diagram illustrating an internal configuration of an encoding device.

FIG. 4 is a plan view showing a transmission format by a multiplexing circuit.

FIG. 5 is a diagram showing a method of superimposing parameters.

FIG. 6 is a block diagram illustrating a schematic configuration of a transcoder system according to a second embodiment of the present invention.

FIG. 7 is a diagram showing a configuration of a conventional transcoder system.

FIG. 8 is a plan view showing a transmission format by a conventional transcoder system.

[Explanation of symbols]

 Reference Signs List 1 decoding device 2 coding device 11 decoding unit 12 multiplexing unit 21 separation unit 22 coding unit 23 parameter buffer 111 TS filter 112 video decoding circuit 113 variable length decoding circuit 114 multiplexing circuit 211 demultiplexing circuit 212 video coding Circuit 213 Coding control circuit

 ──────────────────────────────────────────────────続 き Continuing on the front page F term (reference) 5C059 KK11 MA00 MC38 ME01 PP16 RB01 RB08 RC11 SS02 UA02 UA05 5C063 AA01 AB03 AB07 AC01 AC10 CA11 CA12 CA23 DA07 DA13 5K028 AA01 BB06 DD01 DD02 EE03 KK01 KK03 MM04 SS05

Claims (10)

[Claims] 1. A transcoder system comprising a decoding device and an encoding device, wherein the decoding device decodes a received digital signal to generate digital video data; Means for extracting parameter data used when decoding the digital signal by means; and when multiplexing the digital video data and the parameter data, shifting the parameter data forward by at least one frame or more. A transcoder system comprising: multiplexing means for multiplexing; and transfer means for transferring multiplexed data multiplexed by the multiplexing means to the encoding device. 2. The encoding apparatus according to claim 1, further comprising: separating means for separating the multiplexed data transferred by the transfer means into the digital video data and the parameter data; 2. The transcoder system according to claim 1, further comprising: encoding means for encoding the digital video data based on the digital video data. 3. The encoding device includes a storage unit that stores the parameter data separated by the separation unit, and the encoding unit performs the digital processing based on the parameter data stored in the storage unit. 3. The transcoder system according to claim 2, wherein the video data is encoded. 4. A processing method for a transcoder system comprising a decoding device and an encoding device, comprising: a decoding step of decoding a received digital signal to generate digital video data; An extraction step of extracting parameter data used in decoding a digital signal; and multiplexing the digital video data and the parameter data by shifting the parameter data at least one frame earlier. A multiplexing step; a transfer step of transferring the multiplexed data multiplexed by the multiplexing step to the encoding device; and a transfer of the multiplexed data transferred by the transfer step to the digital video data and the parameter data. A separating step for separating into A coding step of coding the digital video data based on the parameter data obtained. 5. A storage step for storing the parameter data separated by the separation step, wherein the encoding step encodes the digital video data based on the parameter data stored by the storage step. 5. The transcoder system according to claim 4, wherein: 6. A program for a transcoder system comprising a decoding device and an encoding device, the decoding device comprising: a decoding process for decoding a received digital signal to generate digital video data; An extraction process for extracting parameter data used when decoding the digital signal by the decoding process; and when multiplexing the digital video data and the parameter data, the parameter data is at least one frame earlier. A program for executing a multiplexing process of shifting and multiplexing, and a transfer process of transferring multiplexed data multiplexed by the multiplexing process to the encoding device. 7. A separating process for separating the multiplexed data transferred by the transfer process into the digital video data and the parameter data to the encoding device; 7. The non-transitory computer-readable storage medium according to claim 6, further comprising: an encoding process that encodes the digital video data based on the digital video data. 8. The method according to claim 1, wherein the encoding device executes a storage process of storing the parameter data separated by the separation process in a memory, wherein the encoding process stores the parameter data stored in the memory by the storage process. The program according to claim 7, wherein the digital video data is encoded based on data. 9. A program for a transcoder system comprising a decoding device and an encoding device, the decoding device comprising: a decoding process for decoding a received digital signal to generate digital video data; An extraction process for extracting parameter data used when decoding the digital signal by the decoding process; and when multiplexing the digital video data and the parameter data, the parameter data is at least one frame earlier. A multiplexing process for shifting and multiplexing, and a transfer process for transferring the multiplexed data multiplexed by the multiplexing process to the encoding device, are executed, and transferred to the encoding device by the transfer process. Separation processing for separating the multiplexed data into the digital video data and the parameter data, A program characterized by executing the an encoding process for encoding the digital video data based on the separated said parameter data was by sense. 10. The method according to claim 10, wherein the encoding device executes a storage process of storing the parameter data separated by the separation process in a memory, wherein the encoding process stores the parameter data stored in the memory by the storage process. 10. The program according to claim 9, wherein the digital video data is encoded based on data.