This application is based upon and claims the benefit of priority from Japanese Patent Application No. 2015-014613, filed on Jan. 28, 2015; the entire contents of which are incorporated herein by reference.
Embodiments of the present invention relate to a transmitting apparatus, a receiving apparatus, a transmitting method and a receiving method, which can efficiently transmit data.
As an example of a multimedia interface between a video transmitting apparatus, such as a DVD player or a set-top box, and a video receiving apparatus, such as a TV set or a monitor, HDMI(Trademark) (High Definition Multimedia Interface) standard has been proposed. A device having a HDMI output terminal is referred to as a source device and a device having a HDMI input terminal is referred to as a sink device. The video transmitting apparatus is the source device and the video receiving apparatus is the sink device. Also, a device including a HDMI input terminal and a HDMI output terminal and having functions of both of the source device and sink device is referred to as a repeater device.
A HDMI communication device configured to perform communication in accordance with the HDMI standard as described above includes a TMDS (Transition Minimized Differential Signaling) transmitter for transmitting video, audio and auxiliary information; a +5V power supply signal transmitter for notifying a source ready state to a sink-side device when the source device is connected to the sink device or repeater device; a HPD signal transmitter for transmitting a HPD (Hot Plug Detect) signal to notify a sink ready state, which indicates that a preparation for receiving video information in the sink device or repeater device has been made, to the source-side device; and a EDID transmitter for transmitting EDID (Extended Display Identification Data) which is data such product information of the connected sink device, suitable video formats and the like. Also, depending on devices, a HDCP (High-bandwidth Digital Content Protection) certifying module for certifying the sink device and a CEC transmitter for transmitting CEC (Consumer Electronics Control), which is control-modification commands, are provided.
According to one embodiment, a transmitting apparatus includes a transmitter. The transmitter is configured to add pixel data of a decoded video and additional data which is different from the pixel data to one transmission pixel. The transmitter is configured to transmit the one transmission pixel and size information to an external device. The size information indicates a size of an area occupied by the pixel data in the one transmission pixel.
Embodiments will be now described with reference to the accompanying drawings.
Various embodiments will be described hereinafter with reference to the accompanying drawings.
In the data transmission system, a reproduction device 100, which is a source device in the present embodiment, and a display device 200, which is a sink device, are connected to each other by a HDMI cable 300.
The reproduction device 100 has a disk drive 101 and is configured to reproduce (decode) coded video data stored in an optical disk or the like and to output the decoded video data to the display device 200 through the HDMI cable 300. The display device 200 has a display module 206 and is configured to display a video using the received video data.
The reproduction device 100 includes the disk drive 101, a memory 102, a communication module 103, a decoding module 104, and a HDMI transmitter 105. Each of such components 101 to 105 is embodied as a hardware circuit, and lines connecting the components in the figure represent electrical wrings, such as the dedicated lines or general-purpose communication buses on a board. Also, for example, partial functions, such as the decoder module 104, can be embodied by software, but even if such functions is embodied, the functions may be considered as being embodied by hardware circuits including a program storage memory and a CPU.
The disk drive 101 reads coded video data stored in the optical disk and then outputs the video data to the decoding module 104. Also, the memory 102 is a memory module, such as HDD or SSD, and is configured to store therein a prerecorded coded video data or coded video data received through a network. In addition, the memory 102 is configured to output the stored coded video data to the decoding module 104. The communication module 103 is a transceiver for a wireless LAN, a wired LAN, a mobile communication and the like, and is configured to acquire coded video data by communication. For example, the coded video data to be acquired is a corded video data published on internet public pages or coded video data provided by a server for VoD service. Namely, the communication module 103 acquires coded video data stored in external equipment. Also, the communication module 103 outputs the acquired coded video data to the decoding module 104.
The decoding module 104 decodes the coded video data (compressed video data) inputted thereto to generate a non-compressed video data. The decoding module may be a hardware decoder, or if the reproduction device 100 has a CPU, the CPU may be configured to read and run a decoding program from a memory. Also, formats of the video data obtained herein are various. For example, as color space formats, formats, such as RGB(RGB4:4:4), YCbCr4:4:4, YCbCr4:2:2, and YCrCb4:2:0, can be conceived. Also, if, in future, YCbCr4:1:1 is prescribed in the HDMI standard, the format may be used. As RGB formats, formats, such as 8 bit format, in which a data amount of each of R, G and B elements is 8 bit, 10 bit format, in which the data amount is 10 bit, 12 bit format, in which the data amount is 12 bit, and 16 bit format, in which the data amount is 16 bit, are included. As YCbCr4:4:4, YCbCr4:2:2 and YCrCb4:2:0 formats, formats, such as 8 bit format, in which a data amount of each of Y, Cb and Cr elements is 8 bit, 10 bit format, in which the data amount is 10 bit, 12 bit format, in which the data amount is 12 bit, and 16 bit format, in which the data amount is 16 bit, are included. As resolution formats, 640×480, 1280×720, 1980×1080, 3840×2160, 4096×2160, 7680×4320 and the like can be conceived and as frame rate formats, 30 Hz, 50 Hz, 60 Hz and the like can be conceived. Also, the decoding module 104 outputs the generated video data to the HDMI transmitter 105.
The HDMI transmitter 105 converts the video data inputted from the decoding module 104 to a video signal of a predetermined transmission format and then outputs the video signal to the display device 200 through the HDMI cable 300.
The display device 200 includes a HDM receiver 201, a communication module 202, a tuner 203, a signal processor 204, a displaying processor 205 and a display module 206. The HDMI receiver 201 receives the video signal from the reproduction device 100, converts the video signal to a video data of a format, which is capable of being processed by the displaying processor 205, and then outputs the video data to the displaying processor 205. The communication module 202 is a transceiver for a wireless LAN, a wired LAN, a mobile communication and the like, and is configured to acquire coded video data by communication. For example, the coded video data to be acquired is a corded video data published on internet public pages or coded video data provided by a server for VoD service. Also, the communication module 202 is configured so that the acquired coded video data is decoded by a decoding module, not shown, and the decoded video is outputted to the displaying processor 205.
The tuner 203 is configured to receive a broadcasting signal of television broadcasts. The signal processor 204 processes and converts the received broadcasting signal to a video data and then outputs the video data to the displaying processor 205. The displaying processor 205 converts the video data inputted from the HDMI receiver 201 and signal processor 204 to a video signal of a format, which is capable of being displayed by the display module 206, and then outputs the video signal to the display module 206. The display module 206 displays a video using the inputted video signal.
Also, the displaying processor 205 may include a selector to select one video from videos received by the HDMI ereceiver 201, communication module 202 and tuner 203 depending on operations of a user and then to output the selected video to the display module 206. Alternatively, the selector may be configured to select a plurality of videos depending on an operation of the user and thus to allow the plurality of videos to be displayed as a so-called multi-screen display on the display module 206. At this time, such operations of the user section select a video, for example, depending on operations of a remote controller. Alternatively, an operation signal in accordance with operations of the user on a remote controller application installed in a smart phone or tablet, not shown, may be received by the communication module 202 via a wireless/wired LAN and then, the selector may selects a video depending on the operation signal.
Also, the displaying processor 205 may be configured to output a video data, which is identical to a video data to be outputted to the display module 206, to the communication module 202. In this case, the communication module 202 transmits the inputted video data to the external device. In addition, the displaying processor 205 may be configured so that the video data is outputted to and encoded by an encoding module, not shown, and the communication module 202 may be configured to transmit the encoded video to the external device.
The HDMI transmitter 105 includes a TMDS encoder 151, a microcomputer 152, a communication part 153 and the like. Also, the HDMI receiver 201 includes a TMDS decoder 251, a microcomputer 252, an EDID storage memory 253 and the like.
To the TMDS encoder 151, a video data of a format, such as RGB, YCbCr4:4:4, YCbCr4:2:2, YCbCr4:2:0 and YCbCr4:1:1 is inputted. Then, the TMDS encoder 2151 uses the inputted video data to generate data, in which the video data is arranged at a predetermined position. Also, the TMDS encoder 151 encodes the video data to a predetermined pixel encoding format. Further, the TMDS encoder 151 outputs the generated data to each of a channel 1 (CH1), channel 2 (CH2) and channel 3 (CH3) of a HDMI interface. In addition, differential amplifiers, not shown, convert the data outputted from the TMDS encoder 151 to differential signals and then outputs the differential signals to transmission lines of channels 0 to 2. The differential amplifiers are provided to correspond to each of the transmission lines of channels 0 to 2. Also, the differential signals are transmitted to the HDMI receiver 201 via the transmission lines of channels 0 to 2. Further, the differential amplifiers output a TMDS clock to a clock channel (CK). In addition, the TMDS decoder 251 outputs a pixel data of the video at a timing synchronized with the TMDS clock.
The HDM receiver 201 is provided with a differential amplifier (not shown) for each of channels 0 to 2. The differential amplifiers receives differential signals from the channels 0 to 2 to convert the differential signals to data and then to output the data to the TMDS decoder 251. Also, the TMDS decoder 251 decodes and then outputs the data to the displaying processor 205.
The microcomputer 152 of the reproduction device 100 is connected to the microcomputer 252 of the sink device via a CEC (Consumer Electronics Control) line and a HPD (Hot Plug Detect) line. The microcomputer 152 and the microcomputer 252 transmit information for mutually controlling between the devices to each other via the CEC line. Also, the microcomputer 252 receives a notification of turning on the HDMI transmitter 105 via a PW+5V line, and then if a preparation for receiving HDMI signals in the HDMI receiver 201 is completed, notifies the effect of signal transmitting preparation completion to the HDMI transmitter 105 via the HPD line.
The communication part 153 of the microcomputer 152 is connected to the EDID (Extended Display Identification Data) storage memory 253 of the sink device via a DDC line. Also, the communication part 153 reads EDID data from the EDID storage memory 253.
In data areas of pixel clocks of this example, 12 bit information can be encoded and thus 36 bit/pixel clock information is transmitted through three channels. Also, a bit length (bit numbers) of one pixel clock is not limited thereto, but for example, the bit length is 8 bit/pixel clocks (24 bits/pixel clock in three channels) if one pixel clock is transmitted at every one TMDS clock (1 cycle) and 16 bit/pixel clock (48 bits/pixel clock in three channels) if one pixel clock is transmitted at every two TMDS clocks (2 cycles). Namely, the HDMI transmitter 105 can change an amount of information to be transmitted per one pixel clock by changing a clock speed (clock frequency) of the TMDS clock. Also, information indicating a bit length (size) of data areas per one pixel clock is included, for example, InfoFrame.
Also, even if a bit length of pixel data per one pixel clock is increased, the number of pixels to be transmitted by one pixel clock is not changed. For example, when a video of RGB4:4:4 format is transmitted at 16 bits/pixel clock, not 12 bits/pixel clock, the number of RGB elements to be transmitted per one pixel clock is similar to those of the example of
Also, although RGB4:4:4 format is shown in
Also, the TMDS encoder 151 adds information, which indicates a bit length of an actual data (pixel data) to be encoded in the storage area of each pixel clock, to the transmitted data, but this will be described with respect to
Also, although the RGB4:4:4 format has been illustrated in the description with respect to
The description with respect to
Also, although the bit length of the data areas can be changed by adjusting the HDMI transmitter 105 and the HDMI receiver 201 upon transmission, this is the same as described above. The HDMI transmitter 105 may add information, which indicates a bit length of data areas, to InfoFrame and thus transmit the information, thereby notifying the bit length of data areas to the HDMI receiver 201. Alternatively, because the bit length of data areas and the TMDS clock speed (frequency) are proportional to each other, the HDMI receiver 201 may recognize the bit length of data areas based on the TMDS clock speed. Alternatively, when information indicating the bit length of data areas is not added to InfoFrame, the HDMI receiver 201 may recognize that the bit length of data area is a predetermined normal bit length.
Also, the HDMI transmitter 105 of the present embodiment is configured to encode the actual pixel data and also the additional information (2 bits/one channel in the example of
A bit length information-supporting flag 60 is stored in 0th bit of bite 1. The flag 60 indicates whether or not the display device 200 or HDMI receiver 201 supports bit length information 63 (described below) transmitted from the HDMI transmitter 105. When the flag indicates “support”, the display device 200 or HDMI receiver 201 can interpret the bit length information 63 transmitted from the HDMI transmitter 105, recognize a bit length of pixel data bits encoded in each pixel clock (bit length) and then extract and decode the supporting bits from each pixel clock as pixel data. If the flag is “non-support”, the HDMI receiver 201 decodes all bits of each pixel clock as pixel data.
In 1st bit of the bite 1, an additional information-supporting flag 61 is stored. The flag 61 indicates whether or not the display device 200 or HDMI receiver 201 supports additional information encoded in an additional information area in each pixel clock. When the flag 61 indicates “support”, i.e., when the flag 60 and flag 61 indicate “support”, the display device 200 or HDMI receiver 201 can recognize an area, in which additional information is encoded, of data areas of each pixel clock based on the bit length indicated by the bit length information 63 and then decode the additional information as additional information. If the flag 60 is “support” and the flag 61 is “non-support”, the HDMI receiver 201 does not decodes the additional information or decodes and then destroys the additional information.
In bite 2, a supporting additional information identifier 62 is stored. The identifier 62 indicates what type of addition information is supported by the display device 200 or HDMI receiver 201. As types of additional information, as described, HDR additional information, audio addition information, vendor-defined additional information, additional information for auxiliary information and the like can be included. Also, for example, identifiers of
If an identifier 66 is stored as the identifier 62, the display device 200 or HDMI receiver 201 supports HDR additional information. Namely, in this case, when video data including HDR additional information is received, the HDMI receiver 201 decodes and outputs pixel data and HDR additional information to the displaying processor 205, and the displaying processor 205 uses the pixel data and HDR additional information inputted thereto to produce a video having a higher contrast ratio than a case where the additional information is not used.
If an identifier 67 is stored as the identifier 62, the display device 200 or HDMI receiver 201 supports audio additional information. Namely, in this case, when video data including audio additional information is received, the HDMI receiver 201 decodes and outputs audio data and audio additional information in auxiliary information to an audio processor, not shown, and the audio processor produces a higher quality audio using the audio data and audio additional information inputted thereto.
Similarly, if an identifier 68 is stored as the identifier 62, the display device 200 or HDMI receiver 201 supports additional information for auxiliary information, and if an identifier 69 is stored as the identifier 62, the display device 200 or HDMI receiver 201 supports vendor-defined additional information
In 0th to 2nd bits of bite 2, an additional information identifier 64 is encoded. The identifier 64 indicates types of information encoded in the additional information bits shown in
Also, although examples in which the flag 60, flag 61 and flag 62 are stored in EDID are shown in
Also, in
Also, the HDMI transmitter 105 may change a bit length per pixel clock depending on identification results of S702. Namely, for example, in respect of the case where a bit length of a video to be transmitted is 10 bits, the HDMI transmitter 105 may output data including additional information of 2 bits or 6 bits using a pixel encoding format having a bit length per pixel clock of 12 bits or 16 bits if S702 is Yes, but may output data, which have no space in pixel clocks, using a pixel encoding format having pixel clocks of 10 bits if S702 is No.
For example, in respect of processing of S803, when a size of data areas of pixel clocks is 12 bits and the bit length information indicates, for example, 10 bits, the HDMI receiver 201 specifies MSB 10 bits of each pixel clock as pixel data and also specifies MLB 2 bits as additional information.
Then, the HDMI receiver 201 extracts and decodes the pixel data and the additional information, and the HDMI receiver 201 and/or other modules process a video, audio and the like using data obtained by decoding (S804). For example, if the additional information is HDR addition information, the displaying processor 205 creates a high contrast video using the decoded pixel data and the decoded HDR additional information.
On the other hand, if the bit length information and the additional information identifier do not exist in InfoFrame (S802 is No), the HDMI receiver 201 process, as pixel data, all information encoded in the data areas of pixel clocks arranged in the video areas of
Also, although a case where a specific bit pattern is not included in additional information is described in the flow of
Although transmission in HDMI is mainly described in the foregoing embodiments, the method of the present embodiments can be applied to standards in which video data obtained by decoding of coded video data, such as RGB:4:4:4, YCbCr4:4:4, YCbCr4:2:2, YCbCr4:2:0 and YCbCr4:1:1 are transmitted. Namely, the method of the present embodiment can be applied, for example, to MHL standard, Display Port standard and other transmission standards, in which a video is transmitted in a non-compression manner.
Although a number of embodiments of the preset invention are described, the embodiments are proposed as examples and thus not intended to limit the scope of the invention. These novel embodiments can be embodied as other various modes and also various omissions, replacements and modifications thereof can be made without departing from the spirit of the invention. The embodiments and variants thereof are encompassed in the scope and spirit of the invention and also encompassed in the scope equivalent to the inventions set forth in the appending claims.
While certain embodiments have been described, these embodiments have been presented by way of example only, and are not intended to limit the scope of the inventions. Indeed, the novel embodiments described herein may be embodied in a variety of other forms; furthermore, various omissions, substitutions and changes in the form of the embodiments described herein may be made without departing from the spirit of the inventions. The accompanying claims and their equivalents are intended to cover such forms or modifications as would fall within the scope and spirit of the inventions.
Number | Date | Country | Kind |
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2015-014613 | Jan 2015 | JP | national |