Multi-format output device, control method for multi-format output device

A multi-format output device includes decoders to decode first encoded data and second encoded data to generate a first video data having a first-type format with first caption data also having the first-type format, and second video data having a second-type format with second caption data also having the second-type format. A conversion unit converts video data of one format type into video data video data having another format-type. A buffer holds the first video data by the period of time needed for the video data conversion processing. A caption conversion unit delays the caption data for the video data conversion processing time and also converts the caption data of one format type to another format type. A multiplexer outputs the first video data with the first caption data followed by the converted video data with the third caption data having the first-type format.

CROSS-REFERENCE TO RELATED APPLICATION

This application is based upon and claims the benefit of priority from Japanese Patent Application No. 2012-203347, filed Sep. 14, 2012, the entire contents of which are incorporated herein by reference.

FIELD

Embodiments described herein relate to a multi-format output device and a control method for multi-format output device.

BACKGROUND

When encoded data of the SD (Standard Definition) format are supplied to a multi-format output device, the encoded data are decoded into SD video data, and the decoded data are then up-converted into HD (High Definition) video data. In this way, the multi-format output device integrates SD video data with HD video data, which is obtained by decoding encoded HD data. The multi-format output device outputs the HD video data when the output format is HD and down converts the HD video data and outputs the down converted data as SD video data when the output format is SD.

Also, the multi-format output device converts SD caption data added to the encoded SD data into HD caption data for the up-conversion of the SD video data into the HD video data. In this way, the multi-format output device integrates the SD caption data with the HD caption data. The multi-format output device multiplexes the HD caption data with the HD video data when the output format is HD, and converts the HD caption data to the SD caption data and multiplexes them with the SD video data when the output format is SD.

However, in the case of outputting the encoded SD data in the SD format, a multi-format output device may have to perform down-conversion after first up-converting the SD video data. As a result, the image quality of the SD video data may deteriorate. Also, in the case of outputting the encoded SD data in the SD format, the multi-format output device may have to convert the caption data into SD caption data after converting them into HD caption data. As a result, the processing becomes complicated.

As described above, since the related multi-format output device carries out conversion twice when outputting SD video data or SD caption data in the SD format, the image quality of the SD video data may deteriorate, and the processing becomes complicated.

DETAILED DESCRIPTION

In general, an embodiment will be explained with reference to the drawings. As an example embodiment, a multi-format output device and a control method for a multi-format output device that can output an HD image with HD captions and/or an SD image with SD captions without complicated processing and without deterioration in image quality is described.

According to an embodiment, a multi-format output device includes a first decoder configured to receive a first-type encoded data and decode the first-type encoded data to generate a first video data having a first-type format (e.g., High-Definition or Standard Definition) and a first caption data having the first-type format, and a second decoder configured to receive a second-type encoded data and decode the second-type encoded data to generate a second video data having a second-type format (e.g., High-Definition or Standard Definition) and a second caption data having the second-type format. A conversion unit configured to convert the second video data to generate a third video data having the first-type format is included. The conversion unit may also be configured to convert first video data to generate a fourth video data having the second-type format. A first buffer is configured to store the first-type encoded data or the first video data for at least a first period of time substantially equivalent to a period of time required for the conversion unit to generate the third video data. A caption conversion unit is configured to delay output of the first caption data for at least the first period of time and generate a third caption data by converting the second caption data to the first-type format. A first multiplexing unit is configured to output the first video data with the first caption data followed by the third video data with the third caption data.

According to another embodiment, a multi-format output device includes a receiving circuit, first and second decoders, a conversion unit, a buffer, a caption conversion unit, a multiplexing unit, and an output unit. The receiving circuit receives a first encoded data and a second encoded data in a video format different from the first encoded data and separates and outputs the first encoded data and the second encoded data. The first decoder decodes the first encoded data supplied from the receiving circuit to generate the first video data and the first caption data. The second decoder decodes the second encoded data supplied from the receiving circuit to generate the second video data and the second caption data. The conversion unit converts the first video data generated by the first decoder into a third video data conforming to the same definition as the second video data. The buffer holds the second video data generated by the second decoder and delays the video data by the period of time needed for the conversion processing in the conversion unit. The caption conversion unit delays the first and second caption data by the period of time and converts the first caption data into a third caption data conforming to the definition. The multiplexing unit multiplexes the third caption data with the third video data and multiplexes the delayed second caption data with the delayed second video data. The output unit outputs the second video data multiplexed with the second caption data when outputting the third video data multiplexed with the third caption data.

FIG. 1is a diagram illustrating an example of the functional configuration of a broadcasting station, wherein a video server100equipped with a multi-format output device10disclosed in this embodiment is set up. As shown inFIG. 1, a video server100, an automatic program sending controller (APC)200, and an in-station clock201are set in a broadcasting station. The APC200outputs an instruction to the video server100to reproduce the program materials that is to be reproduced according to the time shown in the in-station clock201when the in-station clock201reaches the time indicated in a play list formed based on the broadcasting schedule.

The video server100includes a multi-format output device10, a storage device20, and a reproducing controller30. The multi-format output device10is connected to the storage device20by, for example, an Ethernet connection.

Instructions are sent from APC200to the reproducing controller30to control the multi-format output device10to output the designated program material to a prescribed output destination.

The reproducing controller30controls the multi-format output device10to read out encoded SD data and/or the encoded HD data stored in the storage device20. The constituent elements of the multi-format output device10are controlled appropriately to output the program material to the designated output destination.

In this embodiment, the encoded SD data are obtained by encoding the SD video data and SD caption data added to the SD video data. A preset encoding method is used in this example to generate the encoded SD data. The encoded HD data are obtained by encoding the HD video data and the HD caption data added to the HD video data using. A preset encoding method is used in this example to generate the encoded HD data.

FIG. 2is a block diagram illustrating the functional configuration of the multi-format output device10disclosed in this embodiment. The multi-format output device10shown inFIG. 2includes a receiving circuit11, a first decoder12-1, a second decoder12-2, a first buffer13-1, a second buffer13-2, a caption converter14, a first switching unit15-1, a second switching unit15-2, a converter16, a first multiplexer17-1, a second multiplexer17-2, a first output unit18-1, a second output unit18-2, and a controller19.

The receiving circuit11receives encoded data supplied from the storage device20and then selectively outputs the received encoded data to the first or second decoder12-1,12-2. When the encoded data having a single format are supplied continuously, the receiving circuit11outputs the supplied encoded data to the same decoder. When the encoded data having different formats are supplied simultaneously, the receiving circuit11outputs the different encoded data to different decoders.

For example, when the encoded SD data are supplied from the receiving circuit11, the first decoder12-1decodes the encoded SD data to generate SD video data and the caption data for SD. When the encoded HD data are supplied from the receiving circuit11, the first decoder12-1decodes the encoded HD data to generate HD video data and the caption data for HD.

The first decoder12-1outputs the SD video data or HD video data generated by the decoding processing to the first buffer13-1and outputs the SD caption data or the HD caption data to the caption converter14. Similar to the first decoder12-1, the second decoder12-2decodes the encoded SD data or the encoded HD data supplied from the receiving circuit11to generate the SD video data or the HD video data and the caption data for SD or the caption data for HD. The second decoder12-2outputs the SD video data or HD video data generated by the decoding processing to the second buffer13-2and outputs the SD caption data or the HD caption data to the caption converter14.

The SD video data or HD video data are supplied from the first decoder12-1to the first buffer13-1. The first buffer13-1outputs the supplied SD video data or HD video data to the first and second switching units15-1,15-2according to the first read control from the controller19. Based on the first read control, the first buffer13-1delays the output of the SD video data or HD video data to the first switching unit15-1by as much as the time needed for the conversion processing performed by the converter16compared to the output time of the SD video data or HD video data to the second switching unit15-2.

The SD video data or HD video data are supplied from the second decoder12-2to the second buffer13-2. The second buffer13-2outputs the supplied SD video data or HD video data to the first and second switching units15-1,15-2according to the second read control from the controller19. Based on the second read control, the second buffer13-2delays the output of the SD video data or HD video data to the first switching unit15-1by as much as the time needed for the conversion processing performed by the converter16compared to the output time of the SD video data or HD video data to the second switching unit15-2.

The caption converter14receives the caption data for SD or caption data for HD supplied from the first decoder12-1and receives the caption data for SD or caption data for HD supplied from the second decoder12-2.

According to a caption control sent from the controller19, the caption converter14delays outputting of the received SD caption data by as much as the time needed for the conversion processing performed by the converter16, and then outputs the caption data to the first multiplexer17-1.

Also, according to the caption control sent from the controller19, the caption converter14converts received SD caption data into HD caption data, delays outputting of the caption data by as much as the time needed for the conversion processing performed by the converter16, and then outputs the caption data to the second multiplexer17-2.

In addition, according to the caption control sent from the controller19, the caption converter14delays outputting of the received HD caption data by as much as the time needed for the conversion processing performed by the converter16and then outputs the HD caption data to the first multiplexer17-1.

Moreover, according to the caption control sent from the controller19, the caption converter14converts the received HD caption data into SD caption data, delays outputting of the caption data by as much as the time needed for the conversion processing performed by the converter16, and then outputs the SD caption data to the second multiplexer17-2.

According to a first switching control sent from the controller19, the first switching unit15-1switches between outputting, to the first multiplexer17-1, the SD video data supplied from the first buffer13-1and the HD video data supplied from the second buffer13-2, or the HD video data supplied from the second buffer13-2and the SD video data supplied from the first buffer13-1.

According to the first switching control sent from the controller19, the first switching unit15-1switches between outputting, to the first multiplexer17-1, the HD video data supplied from the first buffer13-1and the SD video data supplied from the second buffer13-2, or the SD video data supplied from the second buffer13-2and the HD video data supplied from the first buffer13-1.

According to a second switching control sent from the controller19, the second switching unit15-2switches between outputting, to the converter16, the SD video data supplied from the first buffer13-1and the HD video data supplied from the second buffer13-2, or the HD video data supplied from the second buffer13-2and the SD video data supplied from the first buffer13-1.

According to the second switching control sent from the controller19, the second switching unit15-2switches between outputting, to the converter16, the HD video data supplied from the first buffer13-1and the SD video data supplied from the second buffer13-2, or the SD video data supplied from the second buffer13-2and the HD video data supplied from the first buffer13-1.

When the SD video data are supplied from the second switching unit15-2, the converter16up-converts the supplied SD video data into the HD video data according to a conversion control sent from the controller19. The converter16outputs the HD video data obtained after the up-conversion to the second multiplexer17-2. When the HD video data are supplied from the second switching unit15-2, the converter16down converts the supplied HD video data into the SD video data according to the conversion control sent from the controller19. The converter16outputs the SD video data obtained after the down-conversion to the second multiplexer17-2.

When SD video data are supplied from the first switching unit15-1, the first multiplexer17-1multiplexes the SD caption data supplied from the caption converter14as ancillary data with the supplied SD video data. The first multiplexer17-1outputs the SD video data with the multiplexed SD caption data to the first and second output units18-1,18-2.

When HD video data are supplied from the first switching unit15-1, the first multiplexer17-1multiplexes the HD caption data from the caption converter14as the ancillary data with the supplied HD video data. The first multiplexer17-1outputs the HD video data multiplexed with the HD caption data to the first, second output units18-1,18-2.

When SD video data are supplied from the converter16, the second multiplexer17-2multiplexes the SD caption data supplied from the caption converter14as the ancillary data with the supplied SD video data. The second multiplexer17-2outputs the SD video data multiplexed with the SD caption data for SD to the first and second output units18-1,18-2.

When HD video data are supplied from the converter16, the second multiplexer17-2multiplexes the HD caption data supplied from the caption converter14as the ancillary data with the supplied HD video data. The second multiplexer17-2outputs the HD video data multiplexed with the HD caption data to the first and second output units18-1,18-2.

The first output unit18-1is connected to the first output channel. This output channel is preset to output SD video data or HD video data. In this embodiment, the first output channel outputs the HD video data.

When receiving SD video data from the first multiplexer17-1, the first output unit18-1receives the HD video data from the second multiplexer17-2.

When receiving HD video data from the first multiplexer17-1, the first output unit18-1receives the SD video data from the second multiplexer17-2. According to a first output control sent from the controller19, the first output unit18-1switches the connection to output the HD video data. In this way, the HD video data are output seamlessly to the first output channel.

The second output unit18-2is connected to the second output channel. In this embodiment, the second output channel outputs the SD video data.

When receiving HD video data from the first multiplexer17-1, the second output unit18-2receives the SD video data from the second multiplexer17-2.

When receiving the SD video data from the first multiplexer17-1, the second output unit18-2receives the HD video data from the second multiplexer17-2. According to a second output control sent from the controller19, the second output unit18-2switches the connection to output the SD video data. In this way, the SD video data are output seamlessly to the second output channel.

The controller19is equipped with a CPU (central processing unit) including a microprocessor. According to a reproducing control sent from the reproducing controller30, controller19reads out the encoded SD data or the HD encoded data from the storage device20and controls the first buffer13-1, the second buffer13-2, the caption converter14, the first switching unit15-1, the second switching unit15-2, the converter16, the first output unit18-1, and the second output unit18-2.

In the following example, the processing of the controller19when the multi-format output device10having the configuration described above outputs HD video data from the first output channel and outputs SD video data from the second output channel will be described.

FIG. 3is a flow chart illustrating the processing of the controller19when the multi-format output device10outputs HD video data and SD video data.FIG. 3shows a case, in which the encoded HD data and the SD format are read out from the storage device20, the encoded HD data are supplied from the receiving circuit11to the first decoder12-1, and the encoded SD data are supplied from the receiving circuit11to the second decoder12-2.

FIG. 4is a diagram illustrating the process of outputting the HD video data from the first output unit18-1.

FIG. 5is a diagram illustrating the process of outputting the SD video data from the second output unit18-2.

First, after receiving the reproducing control from the reproducing controller30(step S31), the controller19reads out the encoded HD data and the encoded SD data stored in the storage device20(step S32).

The receiving circuit11outputs the encoded HD data to the first decoder12-1and outputs the encoded SD data to the second decoder12-2. The first decoder12-1decodes the encoded HD data into HD video data and outputs the HD video data from the first frame to the third frame to the first buffer13-1.

The controller19issues the first read control to output the HD video data from the first buffer13-1to the second switching unit15-2for the first frame of the HD video data in the first buffer13-1.

The controller19issues the second switch control to output the HD video data supplied from the first buffer13-1via the second switching unit15-2to the converter16.

The controller19issues a conversion control to start the down-conversion of the HD video data in the converter16(step S33). The converter16takes two frames for pipeline processing the down-conversion and outputs SD video data starting from the third frame to the first and second output units18-1,18-2.

The controller19issues the first read control to output the HD video data supplied from the first decoder12-1to the first switching unit15-1via the first buffer13-1for the third frame.

The controller19issues the first switch control to output the HD video data supplied from the first buffer13-1to the first multiplexer17-1with respect to the first switching unit15-1.

The controller19performs a caption control to output the caption data for HD supplied from the first decoder12-1to the first multiplexer17-1with respect to the caption converter14.

The controller19performs a caption control to convert the caption data for HD supplied from the first decoder12-1into the caption data for SD and output the caption data to the second multiplexer17-2with respect to the caption converter14.

The controller19performs the first output control to output the HD video data multiplexed with the caption data for HD supplied from the first multiplexer17-1with respect to the first output unit18-1.

The controller19performs the second output control to output the SD video data multiplexed with the caption data for SD supplied from the second multiplexer17-2with respect to the second output unit18-2(step S34).

The second decoder12-2decodes the encoded SD data supplied from the receiving circuit11for the 4thframe to the 9thframe into the SD video data and outputs the decoded SD video data to the second buffer13-2.

The controller19performs the second read control to output the SD video data supplied from the second decoder12-2to the second switching unit15-2with respect to the second buffer13-2for the 4thframe.

The controller19performs the second switch control to output the SD video data supplied from the second buffer13-2to the converter16with respect to the second switching unit15-2.

The controller19performs conversion control to start the up-conversion of the SD video data supplied from the second switching unit15-2with respect to the converter16(step S35). The converter16takes two frames for the up-conversion and outputs the HD video data starting from the 6thframe to the first and second output units18-1,18-2after the up-conversion.

The controller19performs the second read control to output the SD video data supplied from the second decoder12-2to the first switching unit15-1with respect to the second buffer13-2for the 6thframe.

The controller19performs the first switch control to output the SD video data supplied from the second buffer13-2to the first multiplexer17-1with respect to the first switching unit15-1.

The controller19performs a caption control to output the caption data for SD supplied from the second decoder12-2to the first multiplexer17-1with respect to the caption converter14. With respect to the caption converter14, the controller19converts the caption data for SD supplied from the second decoder12-2into the caption data for HD and performs a caption control to output the caption data to the second multiplexer17-2.

The controller19performs the first output control to output the HD video data multiplexed with the caption data for HD supplied from the second multiplexer17-2with respect to the first output unit18-1.

The controller19performs the second output control to output the SD video data multiplexed with the caption data for SD supplied from the first multiplexer17-1with respect to the second output unit18-2(step S36).

According to the process shown inFIG. 3, the controller19can seamlessly connect the HD video data obtained from the encoded HD data and the HD video data obtained from the encoded SD data between the 5thframe and the 6thframe in the first output unit18-1(seeFIG. 4). Also, the controller19can seamlessly connect the SD video data obtained from the encoded HD data and the SD video data obtained from the encoded SD data between the 5thframe and the 6thframe in the second output unit18-2.

FIG. 3shows a case in which the SD video data are output to the second output channel at the same time when the HD video data are output to the first output channel. The present invention, however, is not limited to this. Depending on the reproducing control of the reproducing controller30, the controller19can also output the HD video data only to the first output channel. Also, depending on the reproducing control of the reproducing controller30, the controller19can also output the SD video data only to the second output channel.

As described above, in this embodiment, the controller19delays the data output from the first buffer13-1to the first switching unit15-1by as much as the time needed for the processing in the converter16compared to the data output from the first buffer13-1to the second switching unit15-2. Then, the controller19converts the caption data supplied from the first decoder12-1as demanded, delays the caption data by as much as time needed for the processing in the converter16, and outputs the caption data to the first and second multiplexers17-1,17-2. Also, the controller19delays the data output from the second buffer13-2to the first switching unit15-1by as much as the time needed for the processing in the converter16compared to the data output from the second buffer13-2to the second switching unit15-2. Then, the controller19controls caption converter14to convert the caption data supplied from the second decoder12-2as demanded, delays the caption data by as much as the time needed for the processing in the converter16, and outputs the caption data to the first and second multiplexers17-1,17-2. In this way, the multi-format output device10can eliminate the signal delay caused by the up-conversion and down-conversion processing, and it is only necessary to convert the caption data once. Therefore, the complicated control needed in the related art becomes unnecessary. Even if the multi-format output device10outputs the SD video data, it is only necessary to convert the SD video data once. Therefore, deterioration of the SD video data can be reduced.

Consequently, the multi-format output device disclosed in this embodiment can output an HD image with caption for an HD and/or SD image with caption for SD without undergoing complicated processing and without having image quality deterioration.

In the embodiment described above, the case in which the converter16performs either the up-conversion that converts the SD video data to the HD video data or the down-conversion that converts the HD video data to the SD video data has been explained. However, the converter16can also perform a cross conversion that converts first HD video data based on 1080i to second HD video data based on 720p or converts the second HD (720p) video data to the first HD (1080i) video data.

For example, in the case of outputting the first HD video data from the first output channel and the second HD video data from the second output channel, the controller19performs the first and second read controls to delay the output of the video data to the first switching unit15-1by as much as the time needed for the cross conversion with respect to the first and second buffers13-1,13-2.

Also, the controller19performs a caption control to delay the output of the caption data for the first and second HD video data by as much as the time needed for the cross conversion with respect to the caption converter14.

Also, in this embodiment, the case in which the multi-format output device10has the functional configuration shown inFIG. 2has been explained. The multi-format output device, however, can also have other configurations, such as the functional configuration shown inFIG. 6. That is, it is also possible to decode the encoded data by the first and second decoders12-1,12-2after the data are first stored in the first and second buffers13-1,13-2.

In this embodiment, the case in which the first and second output units18-1,18-2are connected to the first and second output channels, respectively, has been explained. The exemplary embodiment, however, is not limited to this. For example, the multi-format output device10can further include a third output unit18-3connected to a third output channel used for outputting the second HD video data based on 720p.

In each of the embodiments, the case in which the multi-format output device10has two sub-systems (that is, two input/output pathways) has been explained. The present disclosure, however, is not limited to this. For example, an exemplary embodiment can include a multi-format output device10with more than two sub-systems, such that additional buffers/decoders/switches/multiplexers/output units, etc. may be incorporated to accommodate additional input/output formats as desired.

In each of the embodiments, the case in which the multi-format output device10has one converter16has been explained. The embodiments of the present disclosure, however, are not limited to this configuration. For example, the exemplary embodiment can be embodied in the same way even if the multi-format output device10has two or more converters.

Also, the multi-format output device is not limited use in a video server. The embodiments can be applied to any system that requires mutual conversion and output of video signal in a plurality of formats.