WO2016006107A1

WO2016006107A1 - Image transmission device, image reception device, and image transmission method

Info

Publication number: WO2016006107A1
Application number: PCT/JP2014/068609
Authority: WO
Inventors: 稲田　圭介; 甲　展明; 浩朗伊藤; 健木佐貫; 谷田部　祐介; 吉澤　和彦
Original assignee: 日立マクセル株式会社
Priority date: 2014-07-11
Filing date: 2014-07-11
Publication date: 2016-01-14

Abstract

An image transmission device (100) that converts an encoded image stream into image data and outputs the result to an image reception device (200) via a transmission path (300) is provided with: an image data processing unit (113) that performs decoding processing of an encoded image stream containing a first frame group and a second frame group; and a data transfer unit (115) that outputs the decoded images of the first frame group as image data during an effective pixel period (406) and outputs the encoded image stream of the second frame group during a blanking period (407). In this way, a smaller amount of data is transmitted via the transmission path between the image transmission device and the image reception device, the load resulting from interpolation frame generation and the like in the image reception device is reduced, and it becomes possible to display video at a higher frame rate.

Description

Image transmission device, image reception device, and image transmission method

The present invention relates to an image transmission device, an image reception device, and an image transmission method.

In recent digital image processing, the number of pixels has been increased, such as 4K2K (3840 × 2160 pixels) display for general users and HD (High Definition: 1920 × 1080 pixels) for broadcasting. An HDMI (High Definition Multimedia Interface, HDMI Licensing, LLC registered trademark) standard is a method for transmitting image data (also referred to as video data or moving image data) between devices. In the latest HDMI 2.0 standard, it is possible to transmit 4K2K resolution image data at a frame rate up to 60 frames / second. On the other hand, in Japan and Europe, a method of broadcasting 4K2K resolution image data at 120 frames / second is being studied. As described above, when image data with 4K2K resolution and 120 frames / second is adopted in broadcasting, content distribution, etc., the transmission bandwidth is insufficient in the HDMI 2.0 standard.

As a technique for solving this, Patent Document 1 discloses that “a playback device that decodes a video signal encoded by a motion vector and a display device that displays the decoded video signal at a high frame rate are separated. In the case, the frame rate conversion is performed using the motion vector obtained by the decoding process in the playback device in the display device ”.

JP 2007-274679 A

According to the technique of Patent Document 1, it is not necessary to connect a playback device and a display device with a high transmission amount cable corresponding to high frame rate video. However, the display device of Patent Document 1 requires a decoding unit, a motion vector buffer, an interpolation vector generation unit, an interpolation frame generation unit, and the like in order to generate an interpolation frame from a motion vector, which places a heavy burden on the display device side. Also, the device configuration must be compatible.

An object of the present invention is to provide an image transmission apparatus and an image reception apparatus that transmit image data with a smaller amount of data from the transmission side and that do not require generation of an interpolation frame on the reception side.

The present application includes a plurality of means for solving the above-described problems. For example, in an image transmission apparatus that converts an encoded image stream into image data and outputs the image data to a transmission path, the first frame group and the first frame group An image data processing unit that performs a decoding process of an encoded image stream including two frame groups, and outputs a decoded image of the first frame group as image data in an effective pixel period, and encodes the second frame group And a data transfer unit that outputs the image stream during the blanking period.

Further, in an image receiving apparatus that inputs image data via a transmission path and displays the image data on a display unit, a data receiving unit that inputs a decoded image of a first frame group and an encoded image stream of a second frame group as image data And an image data processing unit that performs a decoding process on the input encoded image stream of the second frame group, and a switch between the decoded image of the first frame group and the decoded image of the second frame group, to the display unit An output switching unit for outputting is provided.

In addition, in an image transmission method for converting an encoded image stream into image data and outputting the image data to a transmission path, a step of decoding an encoded image stream including a first frame group and a second frame group; A step of outputting, as data, a decoded image of the first frame group during an effective pixel period, and outputting an encoded image stream of the second frame group during a blanking period.

According to the present invention, it is possible to transmit a smaller amount of data between the image transmission device and the image reception device, and it is possible to reduce a burden such as interpolation frame generation in the image reception device.

1 is a block diagram illustrating an image transmission system according to Embodiment 1. FIG. FIG. 3 is a block diagram showing an internal configuration of an image data processing unit 113 in the image transmission apparatus 100. The block diagram which shows the other internal structure of the image data process part 113. FIG. FIG. 3 is a block diagram showing an internal configuration of an image data processing unit 206 in the image receiving apparatus 200. The figure which shows the effective pixel period and blanking period in 1 frame period. The figure which shows an example of the display timing of a frame row | line. The figure which shows an example of the transmission timing of the image data of FIG. The figure which shows an example of the display timing of an encoding image stream. The figure which shows an example of the transmission timing of the image data of FIG. The figure which shows the example of description of EDID (Example 2). The figure which shows the example of description of the maximum frame rate of an image receiver. The figure which shows the example of a description of the corresponding encoding system of an image receiver. The figure which shows the example of a description of the response | compatibility to the encryption / decryption process of an image receiver. The figure which shows the example of a description of the encryption key system corresponding to an image receiving apparatus. The figure which shows the example of description of the image data transmission system corresponding to an image receiver. The figure which shows the example of description of the maximum resolution of an image receiver.

Hereinafter, embodiments of an image transmission device and an image reception device according to the present invention will be described with reference to the drawings.

FIG. 1 is a block diagram illustrating an image transmission system according to the first embodiment. The image transmission system has a configuration in which an image transmission apparatus 100 that transmits image data and an image reception apparatus 200 that receives and displays the transmitted image data are connected by a cable (transmission path) 300.

The image transmission device 100 is a device that decodes and transmits (transmits) an encoded image stream. The image transmission device 100 receives image data that has been decoded so that the digital broadcast can be received and viewed, and image data that has been captured by a camera or the like. To output to another device (image receiving device). Examples of the image transmission apparatus 100 include a recorder, a set top box, a personal computer with a built-in recorder function, a mobile phone with a camera function and a recorder function, and a camcorder.

The image receiving device 200 is a device that receives image data via an HDMI cable or the like and displays an image on a monitor. Examples of the image receiving apparatus 200 include a digital TV, a display, a projector, a mobile phone, a signage device, a monitor for a monitoring camera, and the like.

The cable 300 is a transmission path for transmitting image data and the like (data communication) between the image transmission apparatus 100 and the image reception apparatus 200. As an example of the cable 300, there is a wired cable corresponding to the HDMI standard or the Display Port standard, or a data transmission path for performing data communication by a wireless method.

First, the configuration of the image transmission apparatus 100 will be described.
Image data is input to the

input units

101, 102, and 103. As an example of image data to be input, digital broadcast broadcast waves from a relay station such as a broadcast station or a broadcast satellite are input to the input unit 101. The input unit 102 inputs digital broadcasts, information contents, and the like distributed via a network using an Internet broadband connection. The input unit 103 receives a digital broadcast or digital content recorded on an external recording medium.

The tuner receiving unit 105 is a reception processing unit that converts a broadcast radio wave input to the input unit 101 into a bit stream. Here, the radio wave of the RF band (Radio Frequency) is frequency-converted to the IF band (Intermediate Frequency) and further demodulated to obtain a bit stream signal. As an example of a multiplexing system for generating a bit stream, there are an MPEG2-TS (Transport Stream) system, a format according to MPEG2-TS, an MMT / TLV (MPEG Media Transport / Type Length Length) system, and the like. The subsequent bit stream will be described using MPEG2-TS as an example.

Further, the tuner receiving unit 105 detects and corrects a code error that occurs during transmission, and de-scrambles the error-corrected MPEG2-TS. Then, one transponder frequency on which a program to be viewed or recorded is multiplexed is selected, and the bit stream in the selected one transponder is separated into audio and video packets of one program. MPEG2-TS from the tuner receiving unit 105 is supplied to the stream control unit 111 through the data bus 191.

In order to keep the interval when the tuner receiving unit 105 receives a packet, the stream control unit 111 includes a PTS (Presentation Time Stamp) that is time management information from the received packet, and a reference decoder inside the MPEG system STC (System Time Clock) is detected, and a time stamp is added at the timing corrected by the detection result. The packet with the time stamp added is supplied to one or both of the image data processing unit 113 and the recording media control unit 107. Data supply to the image data processing unit 113 is used in a mode for viewing image data. Data supply to the recording medium control unit 107 (via the data bus 193) is used in a mode for recording image data on a recording medium. As this recording medium, a recording medium 108 built in the image transmission apparatus 100 is used together with an external recording medium. Examples of these recording media include an optical disk, a magnetic disk, and a semiconductor memory.

The network receiving unit 106 receives digital broadcast and digital content (MPEG2-TS) distributed via the network and input to the input unit 102, and supplies them to the stream control unit 111 through the data bus 192.

The recording medium control unit 107 reads an external recording medium connected to the input unit 103 or a digital broadcast or digital content (MPEG2-TS) recorded on the built-in recording medium 108 and controls the stream through the data bus 193. Supplied to the unit 111. The stream control unit 111 selects at least one of these inputs and outputs it to the image data processing unit 113.

The image data processing unit 113 generates the

image data

150 and 151 using the MPEG2-TS input from the stream control unit 111. In this embodiment, the frame group constituting the image stream is divided into a first frame group and a second frame group, and the image data 150 is the first frame group obtained by decoding the MPEG2-TS. The decoded image and image data 151 is an encoded image stream including the second frame group. As an example of an encoded image stream including the second frame group, not only MPEG2-TS but also an encoded second frame group obtained by re-encoding a decoded image obtained by temporarily decoding MPEG2-TS It may be an image stream and may include information relating to encoding.

The data transfer unit 115 converts the

image data

150 and 151 generated by the image data processing unit 113 into a signal in a format suitable for cable transmission, and outputs the signal to the cable 300 from the output unit 116. At that time, the output image data 150 and the image data 151 are output while being switched between the effective pixel period and the blanking period of the cable transmission path. For example, the image data 150 is output during the effective pixel period, and the image data 151 is output during the blanking period.

A signal for the user to operate the image transmission apparatus 100 is input to the input unit 104. An example of the input unit 104 is a remote control receiver. The operation signal input to the input unit 104 is sent to the control unit 110 via the user interface (IF) 109. The control unit 110 controls the entire image transmission apparatus 100 according to the operation signal. An example of the control unit 110 is a microprocessor.

The image data output from the image transmission device 100 is transmitted (transmitted) to the image reception device 200 via the cable 300. The HDMI standard describes an example of a signal format suitable for cable transmission of image data. According to this standard, image data is TMDS (registered trademark of Transition の Minimized Differential Signaling, Silicon Image, Inc.). Are transmitted according to the data transmission format.

Next, the configuration of the image receiving apparatus 200 will be described.
Image data transmitted via the cable 300 is input to the input unit 201 and sent to the data receiving unit 205. The data receiving unit 205 separates the received data into image data 250 and image data 251 and supplies the image data 250 to the image data processing unit 206. The image data 250 and the image data 251 correspond to the image data 150 and the image data 151 generated by the image transmission apparatus 100, respectively.

The image data processing unit 206 performs decoding processing corresponding to the image processing performed by the image data processing unit 113 in the image transmission apparatus 100 on the

image data

250 and 251 to generate respective decoded images. In addition, the decoded images for the

image data

250 and 251 are switched and output to the display processing unit 207. As an example, it is assumed that the input image data 250 is an uncompressed decoded image and the image data 251 is an encoded image stream. In this case, the image data processing unit 206 performs a decoding process on the image data 251 to generate a decoded image. Then, a decoded image for the image data 250 and a decoded image for the image data 251 are alternately output.

The display processing unit 207 performs display processing on the input decoded image. Examples of display processing include OSD superimposition processing, enlargement / reduction processing for conversion to the resolution of the display unit 208, rotation processing, frame rate conversion processing, and the like. The display-processed image is output to the display unit 208.

The display unit 208 converts the input image into a signal that matches the display method and displays it on the screen. Examples of the display unit 208 include a liquid crystal display, a plasma display, an organic EL (Electro-Luminescence) display, and a projector projection display.

The input unit 202 receives a signal for the user to operate the image receiving apparatus 200. An example of the input unit 202 is a remote control receiver. The operation signal input to the input unit 202 is sent to the control unit 204 via the user IF 203. The control unit 204 controls the entire image receiving apparatus 200 according to the operation signal.

The cable 300 is used not only to transmit image data but also to communicate various information between the image transmission device 100 and the image reception device 200. For example, an operation signal from the user can be transferred between the

control units

110 and 204 of both apparatuses.

Next, the configuration and operation of each part of the image transmission system will be described in detail.
FIG. 2 is a block diagram illustrating an internal configuration of the image data processing unit 113 in the image transmission apparatus 100. The decoding unit 10 receives the encoded image stream 500 supplied from the stream control unit 111, performs a decoding process, and generates a decoded image 510 (corresponding to the image data 150 in FIG. 1). The decoded image 510 is a decoded image of the first frame group. The encryption unit 11 performs encryption processing on a part or all of the encoded image stream 500, and the encrypted encoded image stream 511 (corresponding to the image data 151 in FIG. 1) of the second frame group. Generate. Here, the encryption unit 11 uses the pixel data included in the decrypted image 510 supplied from the decryption unit 10 as the encryption key 519. Thereby, the secrecy of the encrypted encoded image stream 511 output on the transmission path can be improved. An input signal 501 is a control signal supplied from the control unit 110 and controls the operations of the decryption unit 10 and the encryption unit 11.

FIG. 3 is a block diagram showing another internal configuration of the image data processing unit 113 in the image transmission apparatus 100 as a modification of FIG. The decoding unit 10 receives the encoded image stream 500 supplied from the stream control unit 111, performs a decoding process, and generates decoded

images

510 and 512. The decoded image 510 is a decoded image of the first frame group, and the decoded image 512 is a decoded image of the second frame group. The encoding unit 12 performs a re-encoding process on the decoded image 512 of the second frame group, and generates an encoded image stream 513 of the second frame group. As an example of the re-encoding method, H.264 H.264 / AVC, H.H. H.265 / HEVC, Motion JPEG, MPEG2 and the like. The encryption unit 11 performs an encryption process on part or all of the encoded image stream 513 of the second frame group, and generates an encrypted encoded image stream 511 '. Here, the encryption unit 11 uses the pixel data included in the decrypted image 510 supplied from the decryption unit 10 as the encryption key 519. According to the configuration of FIG. 3, the input encoded image stream 500 can be converted into an encoded image stream 511 ′ of a different encoding method and output.

As yet another modified example, a part of the frame sequence of the encoded image stream 500 supplied from the stream control unit 111 is thinned out, and the decoded image of the first frame group and the encoded image stream 511 of the second frame group. Can be generated and output.

FIG. 4 is a block diagram showing an internal configuration of the image data processing unit 206 in the image receiving apparatus 200. From the data reception unit 205, a decrypted image (image data 250) of the first frame group and an encrypted encoded image stream (image data 251) including the second frame group are supplied. The encryption / decryption unit 30 receives the encrypted encoded image stream 251 including the second frame group, performs a decoding process for the encryption, and generates an encoded image stream 610. Here, the encryption / decryption unit 30 uses the pixel data included in the decrypted image (image data 250) of the input first frame group as the encryption key 619. The decoding unit 31 performs an image decoding process on the encoded image stream 610 supplied from the encryption / decryption unit 30, generates a decoded image 611 of the second frame group, and supplies the decoded image 611 to the output switching unit 32. The output switching unit 32 switches between the decoded image 250 of the first frame group and the decoded image 611 of the second frame group and outputs the decoded image 620 to the display processing unit 207. As an example of switching, the decoded image 250 of the first frame group and the decoded image 611 of the second frame group are alternately switched and output. An input signal 601 is a control signal supplied from the control unit 204, and controls operations of the encryption / decryption unit 30, the decryption unit 31, and the output switching unit 32.

In the above description, the encoded image stream of the second frame group in the image data transmitted from the image transmission apparatus 100 to the image reception apparatus 200 is transmitted after being encrypted. Of course, without the encryption process. It is also possible to transmit.

FIG. 5 is a diagram showing an effective pixel period and a blanking period in one frame period. The image transmission apparatus 100 allocates the generated image data to the effective pixel period and the blanking period, and transmits the data to the image reception apparatus 200.

The vertical vertical period 400 includes a vertical blanking period 401 and a vertical effective period 402. The VSYNC signal is a 1-bit signal in which the section of the number of lines defined from the top of the vertical blanking period 401 is “1” and the other vertical blanking period 401 and the vertical effective period 402 are “0”. The prescribed number of lines is, for example, 4 lines.

The horizontal horizontal period 403 includes a horizontal blanking period 404 and a horizontal effective period 405. The HSYNC signal is a 1-bit signal in which the interval of the number of pixels defined from the top of the horizontal blanking period 404 is “1” and the other horizontal blanking period 404 and horizontal effective period 405 are “0”. The prescribed number of pixels is, for example, 40 pixels.

The effective pixel period 406 is an area where both the vertical effective period 402 and the horizontal effective period 405 overlap. The blanking period 407 is one of the vertical blanking period 401 and the horizontal blanking period 404.

In this embodiment, a decoded image (that is, image data 150) of the first frame group is assigned to the effective pixel period 406, and an encoded image stream (that is, image data 151) including the second frame group is assigned to the blanking period 407. assign. The blanking period 407 is narrower (smaller capacity) than the effective pixel period 406, but the image data 151 is compressed and encoded and can be easily stored.

FIG. 6 is a diagram showing an example of the display timing of the frame sequence. The horizontal axis represents time, and shows frames displayed at each time t1, t2,. The frame sequence is divided into a frame 80 included in the first frame group and a frame 81 included in the second frame group. In the example of FIG. 6, the frame 80 and the frame 81 are displayed alternately. is there. In other words, the input frame sequence is alternately divided into a first frame group and a second frame group in the display order.

FIG. 7 is a diagram showing an example of the transmission timing of the image data in FIG. The horizontal axis represents transmission time, and is composed of an effective pixel period 90 and a blanking period 91. When transmitting the data of the frame sequence shown in FIG. 6, the decoded image (image data 150) of the first frame group (frame 80) is output during the effective pixel period 90, and the second frame group (frame 81) is output. The encoded image stream (image data 151) that is included is output in the blanking period 91. The example of FIG. 7 shows that an encoded image stream including the second frame group is output in the vertical blanking period.

Note that a horizontal blanking period can be used as a blanking period for outputting an encoded image stream (image data 151) including the second frame group. In this case, the image data 151 is distributed over each horizontal line. What is necessary is just to arrange. Further, the image data 151 may be output with a delay of one blanking period or more from the blanking period immediately after the effective pixel period in which the immediately preceding image data 150 is output. Further, a plurality of frame data may be included in the same blanking period.

FIG. 8 is a diagram showing an example of the display timing of the encoded image stream. In the figure, I0, B1, B2,... B8 indicate picture sequences in the display order. Each picture is encoded in three layers from the first layer to the third layer. Arrows in the figure indicate pictures to be referred to when each picture is encoded. For example, the picture B1 in the third hierarchy refers to the picture I0 in the first hierarchy and the picture B2 in the second hierarchy. The picture B2 in the second hierarchy refers to the pictures I0 and B4 in the first hierarchy. The picture B4 in the first hierarchy refers to the picture I0 in the first hierarchy. As described above, the pictures of the first hierarchy and the second hierarchy are configured not to refer to the pictures of the lower third hierarchy at the time of encoding. As an example of such a configuration, H.C. 265 / HEVC RA (Random Access).

In such a configuration, the first and second layer pictures I0, B2, B4, B6... That are referred to for coding other pictures are set as the first frame group, The third layer pictures B1, B3, B5, B7... That are not referred to for picture encoding are classified as a second frame group.

FIG. 9 is a diagram illustrating an example of the transmission timing of the image data in FIG. When transmitting the data of the picture sequence shown in FIG. 8, the decoded images of the first layer and second layer pictures I0, B2, B4, B6... (First frame group) are output to the effective pixel period 90. To do. Also, an encoded image stream including the third layer pictures B1, B3, B5, B7... (Second frame group) is output in the blanking period 91. Here, the pictures B1, B3, and B5 in the third layer are output after the output of the pictures to which they refer is completed. For example, the picture B1 is output after the picture B2, and the pictures B3 and B5 are output after the picture B4.

Further, in order to display the picture B1 immediately after the picture I0, the picture information to be displayed immediately before may be output together with the encoded image stream of the picture B1. As the picture information to be displayed immediately before, frame interval information indicating the distance between the picture to be displayed immediately before and the picture in terms of the number of frames may be used. In this example, the frame interval information between the picture B1 and the picture I0 is “1”. Similarly, the frame interval information between the picture B3 and the picture B2 is “1”, and the frame interval information between the picture B5 and the picture B4 is “0”.

The frame interval information may be output together with the image data 151. That is, when the image data processing unit 113 has the configuration of FIG. 2, it is output during the blanking period 91, and when it has the configuration of FIG. 3, it is stored and output in the encoded image stream of the second frame group.

As described above, according to the first embodiment, in the image transmission apparatus 100, the image data processing unit 113 that performs the decoding process of the encoded image stream including the first frame group and the second frame group, and the image data The data transfer unit 115 outputs the decoded image of the first frame group during the effective pixel period 406 and outputs the encoded image stream of the second frame group during the blanking period 407. As a result, the transmission path 300 between the image transmission device 100 and the image reception device 200 is transmitted with a smaller amount of data, and the burden of generating an interpolated frame in the image reception device 200 is reduced, and a higher frame rate is achieved. The video can be displayed.

In the second embodiment, generation and transmission of image data in accordance with the reception / display function of the image receiving apparatus 200 will be described. Although not shown in FIG. 1, the image receiving apparatus 200 is equipped with a ROM (Read Only Memory) that stores EDID (Enhanced Extended Extended Display Identification Data) indicating the performance of the receiving apparatus. In this ROM, image receiving device information which is information relating to reception / display of the image receiving device 200 is added. Examples of the image receiving device information include a maximum frame rate, an encoding method, an encryption method, an image data transmission method, and a maximum resolution.

The image transmission apparatus 100 reads out and acquires the image receiving apparatus information from the ROM storing the EDID of the image receiving apparatus 200 via the cable 300. Then, the transmission destination image receiving apparatus 200 uses the encoded image stream including the decoded image of the first frame group transmitted during the effective pixel period and the second frame group transmitted during the blanking period. Check if playback is supported. By confirming that the device is compatible, the encoded image stream corresponding to the blanking period is transmitted, so that compatibility with an incompatible image receiving device can be maintained.

Also, information (HQ_ENC, HQ_ENCR) for determining whether or not the encryption method applied to the encoded image stream transmitted during the blanking period is supported is read. If the device is compatible, encryption processing is performed, and the encrypted encoded image stream is transmitted. If the device is incompatible, it can be compatible with an image reception device that does not support encryption / decryption processing by transmitting without performing encryption processing. At that time, the image receiving apparatus can notify the user by displaying on the display unit 208 that the encryption / decryption processing is not supported.

FIG. 10 is a diagram showing a description example of EDID, and shows an example of extension to an area called HDMI-VSDB (Vender-Specific Data Block). Bit 2 of the 6th byte is provided with an HQ_transfer flag indicating whether or not the high frame rate reproduction method described in the first embodiment is applicable. Since this area has been treated as a reserved area, “0” is described in a non-compliant legacy device. By describing “1” only for compatible devices, backward compatibility can be maintained. When the HQ_transfer flag is “1”, the description of Byte8, Byte9, and Byte10 is valid. Hereinafter, these description examples will be described.

FIG. 11 is a diagram illustrating a description example of the maximum frame rate of the image receiving apparatus. The value (“1” to “4”) of HQ_FR described in Byte 9 (Bits 7 to 4) indicates 30 fps, 60 fps, 120 fps, and 240 fps (frame persseconds).

FIG. 12 is a diagram illustrating a description example of a corresponding encoding method of the image receiving apparatus. The value (“2” to “5”) of HQ_COMP described in Byte 9 (Bits 3 to 0) is the Motion JPEG format, MPEG2 format, H.264 format. H.264 / AVC format, H.264. It shows that it corresponds to the H.265 / HEVC system.

FIG. 13 is a diagram illustrating a description example of correspondence to the encryption / decryption processing of the image receiving apparatus. The value (“1” to “4”) of HQ_ECR described in Byte 10 (Bits 7 to 4) indicates whether or not the image receiving apparatus supports encryption / decryption processing.

FIG. 14 is a diagram illustrating a description example of the corresponding encryption key method of the image receiving apparatus. The value of HQ_ECRP described in Byte 10 (Bit 3 to 0) indicates which encryption key method is supported when the image receiving apparatus supports encryption / decryption processing (determined from HQ_ECR).

For example, when HQ_ECR is “2” and HQ_ECRP is “1”, the image reception apparatus transmits the first effective pixel period immediately before the blanking period in which the encoded image stream to be subjected to the encryption / decryption process is transmitted. It shows that the top pixel data of the decrypted image of one frame group is used as the encryption key.

As another example, when HQ_ECR is “2” and HQ_ECRP is “5”, the image receiving apparatus transmits in the effective pixel period immediately before the blanking period in which the encoded image stream to be subjected to the decryption process is transmitted. This indicates that the (5 × 2 ¹⁶ ) th pixel data from the beginning of the decrypted image of the first frame group is used as the encryption key.

FIG. 15 is a diagram illustrating a description example of a corresponding image data transmission method of the image receiving apparatus. The values of HQ_DOUTA and HQ_DOUTB described in Byte 11 (Bits 7 to 4) indicate which frame rate transmission method the image receiving apparatus supports.

For example, when HQ_DOUTA is “1” and HQ_DOUTB is “1”, the decoded image of the first frame group input during the effective pixel period and the encoded image including the second frame group input during the blanking period It shows that it corresponds to a high frame rate transmission method using a stream.

FIG. 16 is a diagram showing a description example of the maximum resolution of the image receiving apparatus. The value (“1” to “5”) of HQ_DISP described in Byte 11 (Bits 3 to 0) indicates that the maximum resolution of the image receiving apparatus corresponds to VGA, HD, 2K4K, 4K2K, and 8K4K.

According to the second embodiment, the image transmission apparatus can generate and transmit image data that matches the reception / display function of the transmission destination image reception apparatus by acquiring the image reception apparatus information of the image reception apparatus. . In addition, compatibility can be maintained even if the destination image receiving apparatus does not support the high frame rate playback function.

10, 31: Decoding unit,
11: Encryption unit,
12: Encoding unit,
30: encryption / decryption unit,
32: Output switching unit,
90, 406: effective pixel period,
91,407: blanking period,
100: Image transmission device,
105: tuner receiver,
106: network receiver,
107: Recording media control unit,
108: Recording medium,
109: User IF section,
110: Control unit,
111: Stream control unit,
113: Image data processing unit,
115: Data transfer unit,
150, 151: image data,
200: Image receiving device,
203: User IF section
204: control unit,
205: a data receiving unit,
206: Image data processing unit,
207: a display processing unit,
208: Display section
250, 251: image data,
300: Cable (transmission path).

Claims

In an image transmission apparatus that converts an encoded image stream into image data and outputs it to a transmission path,
An image data processing unit that performs a decoding process of the encoded image stream including the first frame group and the second frame group;
A data transfer unit that outputs the decoded image of the first frame group during the effective pixel period and outputs the encoded image stream of the second frame group during the blanking period as the image data; Image transmission device.
The image transmission apparatus according to claim 1,
The image data processing unit performs a re-encoding process on the decoded image of the second frame group,
The image transmission apparatus, wherein the data transfer unit outputs the encoded image stream of the second frame group after the re-encoding process in the blanking period.
The image transmission apparatus according to claim 1 or 2,
The image data processing unit performs an encryption process on the encoded image stream of the second frame group using a part of the decoded image of the first frame group as an encryption key,
The image transfer apparatus, wherein the data transfer unit outputs the encoded image stream of the second frame group after the encryption processing in the blanking period.
The image transmission apparatus according to claim 1,
The image data processing unit generates frame interval information between a first picture included in the decoded image of the first frame group and a second picture included in the encoded image stream of the second frame group. ,
The image transfer apparatus, wherein the data transfer unit outputs the frame interval information during the blanking period.
The image transmission apparatus according to claim 2,
The image data processing unit includes a first picture included in the decoded image of the first frame group and a second picture included in the encoded image stream of the second frame group after the re-encoding process. Frame interval information is generated and stored in the encoded image stream of the second frame group.
The image transmission apparatus according to claim 3.
The data transfer unit acquires image receiving device information from a transmission destination via the transmission path,
The image data processing unit and the data transfer unit switch a format of a decoded image and an encoded image stream to be output according to the acquired image receiving device information,
The image receiving apparatus information includes at least one information of a maximum frame rate, an encoding method, an encryption method, an image data transmission method, and a maximum resolution.
In an image receiving apparatus that inputs image data via a transmission line and displays the image data on a display unit,
A data receiving unit that inputs a decoded image of a first frame group and an encoded image stream of a second frame group as the image data;
An image data processing unit that performs a decoding process on the encoded image stream of the input second frame group;
An image receiving apparatus comprising: an output switching unit that switches between the decoded image of the first frame group and the decoded image of the second frame group and outputs the switched image to the display unit.
The image receiving device according to claim 7,
When the encoded image stream of the input second frame group is encrypted,
The image data processing unit performs encryption / decryption processing on the encoded image stream of the second frame group by using a part of the decoded image of the first frame group as an encryption key. Receiver device.
In an image transmission method for converting an encoded image stream into image data and outputting it to a transmission path,
Performing a decoding process of the encoded image stream including a first frame group and a second frame group;
Outputting the decoded image of the first frame group during the effective pixel period as the image data, and outputting the encoded image stream of the second frame group during the blanking period. Transmission method.
The image transmission method according to claim 9, wherein
Performing a re-encoding process on the decoded image of the second frame group,
An image transmission method comprising: outputting the encoded image stream of the second frame group after the re-encoding process in the blanking period.
The image transmission method according to claim 9 or 10,
A step of performing an encryption process on the encoded image stream of the second frame group using a part of the decoded image of the first frame group as an encryption key;
An image transmission method comprising: outputting an encoded image stream of the second frame group after the encryption process in the blanking period.