Indication device

Abstract

To provide a television display device that improves convenience when displaying an image obtained by a portable video device such as a camera or a mobile phone on a display device. [Solution] A system including a video device and a video display device selects a first image, a second image, or a third image based on image information acquired from an external device connected to the video display device via a predetermined interface and displays the selected image on a display unit. The display unit performs a slideshow display at a predetermined time interval using multiple first images based on image information obtained by decompressing compressed image information input from the external device via a first interface unit using a decompressor. The display unit also performs a slideshow display at a predetermined time interval using multiple second images based on uncompressed image information input via a second interface unit. An audio output unit outputs audio along with the image display by the display unit.

Description

Technical Field

[0001] The present invention relates to a technology for displaying video information from a video device connected to a display device via an interface on the display device.

Background Art

[0002] In order to connect a video device and a video display device, which is another video device, to view videos and the like, a method of analog connection to transmit video signals and audio signals has been used. However, with the spread of digital devices, a method of digital connection and encrypting and transmitting video signals and audio signals has been used from the viewpoints of preventing image quality deterioration and copyright protection.

[0003] As an example of digital transmission, a method using one cable compliant with the IEEE1394 standard is known. This performs mutual authentication between devices that perform transmission and reception, multiplexes video signals and audio signals after the authentication, and encrypts the multiplexed data by a process called DTCP and then transmits it.

[0004] As another example, the HDMI method is known. In the HDMI method, the baseband signal of a high-definition video signal and an audio signal are time-division multiplexed and encrypted by a process called HDCP to enable transmission.

[0005] As such a conventional technique for multiplexing and transmitting digitized video signals and audio signals, for example, it is disclosed in Patent Document 1 below.

Prior Art Documents

Patent Documents

[0006]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0007] The IEEE 1394 standard, used as a network, has a limited transmission rate, making it impossible to transmit high-resolution video signals with a large amount of information directly as baseband signals. Therefore, the IEEE 1394 standard has the problem of requiring baseband signals to be compressed to reduce the transmission rate. On the other hand, the HDMI method does not consider the recording of the received high-resolution video signal by the receiving device.

[0008] Furthermore, these methods all assume connections between stationary devices located within the home, and did not adequately consider the convenience of connecting portable devices such as digital cameras and mobile phones with video display devices.

[0009] This invention has been made in view of the above problems, and provides a technology to improve the convenience of displaying images obtained from portable video devices such as cameras and mobile phones on a display device. [Means for solving the problem]

[0010] The present invention is characterized in that, by transmitting video acquisition requests to an external video device connected to the display device via a predetermined interface at predetermined periodic intervals, the display device can acquire and display multiple video pieces of information from the external device.

[0011] The multiple images obtained in this way may be displayed in a so-called slideshow format by switching between them, for example, at predetermined periodic intervals. Alternatively, multiple thumbnail images may be generated from these multiple video information and displayed side by side on one screen of the display unit. [Effects of the Invention]

[0012] According to the present invention, it is possible to improve the convenience when displaying an image obtained by a portable video device such as a camera or a mobile phone on a display device.

Brief Description of the Drawings

[0013] [Figure 1] A diagram showing an example of a system including a video device and a video display device according to an embodiment of the present invention. [Figure 2] A diagram showing an example of a video device 100 according to an embodiment of the present invention. [Figure 3] It is an explanatory diagram showing the order of compression signal processing. [Figure 4] A diagram showing an example of a video display device 200 according to an embodiment of the present invention. [Figure 5] A diagram showing another example of a video display device 200 according to an embodiment of the present invention. [Figure 6] A diagram showing an example of a system in which two video devices are connected to each other. [Figure 7] A diagram showing an example of a system in which a video display device and a video device are connected. [Figure 8] A diagram showing an example of a system in which two video devices are wirelessly connected to each other. [Figure 9] A diagram showing another example of a system in which two video devices are wirelessly connected to each other. [Figure 10] A diagram showing an example of an embodiment of a video display device according to the present invention. [Figure 11] A diagram showing another example of an embodiment of a video display device according to the present invention. [Figure 12] A diagram showing an example of thumbnail display in this embodiment. [Figure 13] A diagram showing another example of thumbnail display in this embodiment. [Figure 14] A diagram showing another example of thumbnail display in this embodiment. [Figure 15] A diagram showing an example of attribute information corresponding to each still image stored in the memory 1018 of the video device 1020. [Figure 16] A diagram showing a configuration example of an HDMI interface. [Figure 17] A diagram showing an example of the format of a remote control code. [Figure 18] A diagram showing an example of a method of transmitting a remote control code via a CEC line. [Figure 19] A diagram showing an example of a table of manufacturer codes and device codes corresponding to each interface stored in the video display device 200.

Mode for Carrying Out the Invention

[0014] Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings.

Example

[0015] FIG. 1 shows a first embodiment of the present invention. In FIG. 1, for example, three video devices are shown as video equipment. One is a video device 100, for example, a portable video device capable of receiving a digital broadcast signal from a mobile phone base station antenna 20 or a broadcast transmission tower 30. One is a video display device 200, and another is a receiver 300, for example, a tuner, capable of receiving a digital broadcast signal from the broadcast transmission tower 30. The video device 100 and the video display device 200 are connected by, for example, a bidirectional interface 10, and the video display device 200 and the receiver 300 are connected by another bidirectional interface 11. This enables two-way communication of video signals, other information, and signals between the devices.

[0016] In this embodiment, the portable video device 100 is specifically a digital camera, a video camera, a mobile phone, a game machine, a personal media player, etc. The necessary components are not necessarily the same depending on each form, but in the embodiment shown in FIG. 1, mainly the components necessary for input / output to the outside are described.

[0017] In Figure 1, the mobile phone base station antenna 20 and the antenna 102 of the video device 100 transmit and receive signals. When the video device 100 is used as a mobile phone, it performs signal processing as a normal mobile phone. The video device 100 can also receive content such as movies transmitted from the mobile phone base station antenna 20. In this case, the content can be viewed on the display device and audio output device built into the video device 100, or it can be viewed on a large screen on an external video display device 200 via terminal 101, connection cable 10, and terminal 201. Furthermore, the content can be recorded on a storage medium built into the video device 100 or on a storage medium connected to the video device 100 (for example, memory 121) while viewing the content or for later viewing. Memory 121 can also be used as a recording medium for recording movies and the like.

[0018] Similarly, programs broadcast from the broadcast transmission tower 30 are received by the broadcast receiver 180 of the video equipment 100 and can be viewed on the video equipment 100, or recorded on a storage medium (not shown) built into the video equipment 100, or on a connected storage medium (e.g., memory 121). Furthermore, they can also be viewed on the video display device 200 via terminal 101, connection cable 10, and terminal 201.

[0019] Furthermore, programs broadcast from the broadcast transmission tower 30 are received by the receiving antenna 310 connected to the receiver 300, input to the receiver 300 via the antenna terminal 302, and after appropriate signal processing, are viewed on the video display device 200 via terminal 301, connection cable 11, and terminal 202. In addition, programs selected simultaneously with or separately from viewing can be stored in the memory 321 via a built-in storage medium (not shown) or memory interface 320. The memory 321 recorded in the receiver 300 can also be connected to the memory interface 120 of the video equipment 100. By taking the video equipment 100 outside the home and displaying it on the built-in display device (not shown), programs recorded at home can also be viewed outside the home.

[0020] Furthermore, by equipping the video equipment 100 with an imaging device 110 and a microphone 112, still images and videos can be captured along with audio, and stored as appropriate in a built-in storage medium (not shown) or memory 121. The video and audio stored in the built-in storage medium or memory 121 can be viewed on the video display device 200 via terminal 101, connection cable 10, and terminal 201.

[0021] The embodiment shown in Figure 1 illustrates the case where terminal 101 of the video equipment 100 is connected to terminal 201 of the video display device 200, and terminal 301 of the receiver 300 is connected to terminal 201 of the video display device 200, respectively, using wired cables such as connection cables 10 and 11. However, when transmitting and receiving signals between these video devices, it is not necessary to connect them using wired cables; they can be connected wirelessly. Wireless connections eliminate the hassle of wiring and the need to organize the wiring. Using connection cables has the advantage of being more resistant to interference such as noise compared to wireless connections.

[0022] Figure 2 shows a first embodiment of the present invention and illustrates the specific configuration of the video equipment 100 shown in Figure 1. In Figure 2, the imaging device 110 captures video and still images input through the optical system and converts them into electrical signals. The compression circuit 111 efficiently compresses the captured images by bit, using a compression method such as MPEG2, MPEG4, or AVC / H.264 for video, and a compression method such as JPEG for still images.

[0023] Meanwhile, microphone 112 converts sound waves into electrical signals. Compression circuit 113 efficiently compresses the captured audio signal using a compression method such as MPEG audio.

[0024] When capturing still images with the video equipment 100, the video equipment is rotated depending on the subject being captured, and shooting is performed in either a horizontal or vertical position. Sensor 114 detects whether the video equipment 100 was used for shooting in a horizontal or vertical position. If used in a vertical position, it also detects whether the right or left side of the video equipment 100 is facing upwards. The information detected by sensor 114 is input to the microprocessor 115.

[0025] The multiplexing circuit 116 receives bit-compressed video signals and audio signals from the compression circuits 111 and 113, as well as various information from the microprocessor 115, and multiplexes them according to a predetermined format. When a still image is captured, the audio signal is usually not captured, but the audio signal may be multiplexed in conjunction with the still image capture.

[0026] The various types of information from the microprocessor 115 include position information (horizontal, right vertical, left vertical) using the sensor 114, date, exposure information at the time of shooting, and other information.

[0027] Figure 3 shows the sequence of signal processing for each block, which is commonly performed in image compression. As shown in Figure 3(a), signal processing is performed sequentially from left to right in the top row of the image, and then sequentially from left to right in the second row. As shown in Figure 3(b), if the video equipment 100 is oriented vertically with the right side up, signal processing is performed from bottom to top in the left column, and then from bottom to top in the second column from the left. As shown in Figure 3(c), if the video equipment 100 is oriented vertically with the left side up, signal processing is performed from top to bottom in the right column, and then from top to bottom in the second column from the right.

[0028] If the camera is held vertically during shooting, without information on whether the left or right side is at the top, the captured image cannot be displayed on a display device as it was shot. For this reason, as described above, position information is multiplexed into the video and audio signals as various information from the microprocessor (115). By decompressing the compressed signal and performing signal processing to rotate the decompressed image by 90 degrees using the position information to match the output of the display device, the image can be displayed as it was shot.

[0029] Furthermore, instead of doubling the position information, the microprocessor 115 provides position information to the compression circuit 111 and controls it, as shown by the dotted line from the microprocessor 115 to the compression circuit 111 in Figure 2. This allows the compression circuit 111 to perform the compression signal processing itself according to the video shooting operation and the shooting position of the video equipment 100, eliminating the need for rotation processing during playback. For example, as shown in Figures 3(d) and (e), by performing compression signal processing from the top left to the right of the image at the time of shooting, based on the position information, the image can be displayed exactly as it was shot during playback.

[0030] If the video equipment 100 can capture both still images and videos, as mentioned above, users may choose to shoot still images in landscape or portrait orientation. Similarly, some users may consider using the video equipment 100 in portrait orientation when shooting videos.

[0031] In the case of moving images, rotation signal processing is generally not provided, and if the image is displayed directly on the video display device 200, the image will be rotated horizontally, resulting in unintended capture for the user. Therefore, when capturing images in video mode, if the user rotates the video equipment 100, the sensor 114 detects that it is being used in a vertical position, and the microprocessor 115 displays a warning message on the display device 160. The display device 160 is used as a monitor for the image being captured by the imaging device 110, making it easy to check the message while shooting, and if this is unintentional, it warns the user to switch back to normal horizontal shooting.

[0032] Furthermore, when used in portrait orientation, the microprocessor 115 sends position information to the compression circuit 111 to control it. As a result, the compression circuit 111 processes the compression signal from left to right at the top of the portrait orientation, so that it can be played back according to the shooting operation of the video and the shooting position of the video equipment 100, as shown in Figures 3(d) and (e). This allows for viewing in portrait orientation even on existing televisions. A detailed explanation will be given later.

[0033] In Figure 2, the signals multiplexed by the multiplexing circuit 116 are stored in the storage device 130 via the encryption / decryption circuit 140. For example, a hard disk drive, optical disc drive, or semiconductor memory device can be used as the storage device. The choice of storage device should be determined by considering the desired storage capacity, size, ease of retrieval of the storage medium, and cost. Alternatively, the signals can be stored in the memory 121 via the signal processing circuit 124 and the memory interface 120.

[0034] Regarding information taken by an individual, the copyright belongs to the person who took the photograph, so encryption is usually not necessary when storing it. However, since there is a possibility of losing the storage medium stored in the storage device 130, security can be enhanced by encrypting the output signal of the multiplexing circuit 116 with the encryption / decryption circuit 140 before storing it in the storage device 130 or memory 121.

[0035] The video equipment 100 may support removable memory, or it may have mobile phone functionality or wireless LAN functionality. The memory interface 120 is an interface for removable memory 121, and still images, video, and audio content can be recorded to memory 121 using other devices, and then connected to interface 120 to be recorded to storage device 130 via signal processing circuit 124 and encryption / decryption circuit 140.

[0036] At this time, the signal processing circuit 124 detects whether the content recorded in memory 121 is copyright-protected and whether copying is restricted, and according to the conditions, the encryption / decryption circuit 140 encrypts it and moves it to storage device 130.

[0037] Similarly, when still images, video footage, or audio content are received and input via the wireless interface 122, they are recorded in the storage device 130 via the signal processing circuit 124 and the encryption / decryption circuit 140. In this case as well, the content is encrypted by the encryption / decryption circuit 140 as necessary, in accordance with copyright protection and copying restriction conditions.

[0038] To play and view content stored in the storage device 130, the user selects the content they wish to view using input keys or a remote control (not shown). The selected content is read from the storage device 130, decrypted by the encryption / decryption circuit 140, and separated into video and audio signals by the inverse multiplexing circuit 141.

[0039] Furthermore, when a broadcast is received by the broadcast receiver 180, the encryption / decryption circuit 140 decrypts the broadcast encryption, and if necessary, performs encryption processing for storage using the same encryption / decryption circuit 140, and records it in the storage device 130 and memory 121. When the received broadcast is viewed directly, the video signal and audio signal are separated by the inverse multiplexing circuit 141.

[0040] The separated and compressed video signal is decompressed by the decompression circuit 142 and input to the signal processing circuit 150. The signal processing circuit 150 performs scan line conversion to match the scan lines of the display device 160 and outputs it to the display device 160.

[0041] The separated and compressed audio signal is decompressed by the decompression circuit 143 and output to the audio output device 161. Thus, since the video equipment 100 has a display device 160 and an audio output device 161, it is possible to view the video directly without connecting an external video display device. However, differences in the time required for decompression processing of the video signal and audio signal, and the presence or absence of scan line conversion processing, can cause a sense of incongruity in the time difference between the video signal and the audio output. In particular, if the video signal processing takes time and the audio signal precedes the video signal, the sense of incongruity becomes greater. For example, delay processing of the audio signal is performed within the decompression process to perform so-called lip-syncing. This eliminates the sense of incongruity caused by the discrepancy between the video signal and the audio signal.

[0042] In contrast, when viewing video and audio signals on an external video display device 200, the system checks the scan lines available to the video display device 200. If the scan lines match those of the video signal to be displayed, the signal is output as is. If they do not match, the signal processing circuit 150 converts the scan lines to the required ones, and then the multiplexing circuit 170 performs time-axis multiplexing with the audio signal processed by the signal processing circuit 151. The signal processing circuit 151 compresses the audio signal in the time axis during a period corresponding to the blanking period of the video signal, and performs time adjustments for lip-sync matching as needed. The video and audio signals multiplexed by the multiplexing circuit 170 are input to the encryption circuit 171, where encryption processing necessary for transmission between the video equipment 100 and the video display device 200 is performed, and the signals are output to the video display device 200 via interface 172 and terminal 101.

[0043] As described above, even though it is a moving image, if the video equipment 100 is used in a vertical position and signal processing is performed using compressed signal processing as shown in Figures 3(d) and (e), the signal processing 150 performs scan line conversion to convert it to the number of scan lines that can be captured by the video display device 200 and outputs it. In that case, there will be parts of the screen on the left and right that do not display the signal. This is displayed on the display device 160 in what is known as a side panel state.

[0044] Furthermore, when the signal output from terminal 101 is to be stored at the receiving end, the compressed signal is output without decompression. In this case, the compressed signal from the encryption / decryption circuit 140 is input to the encryption circuit 171, and after encryption necessary for transmission is performed, it is output via interface 172 and terminal 101. In the above explanation, the video signal and audio signal captured from the imaging device 110 and microphone 112, as well as the content input from the memory 121 and wireless interface 122, are recorded in the storage device 130 before being played back. However, if storage is not required, or if the content is to be viewed directly, the processing can be performed by the demultiplexing circuit 141 without performing the encryption and decryption processing for storage in the encryption / decryption circuit 140. This makes it possible to view the video and audio using the display device 160 and audio output device 161 built into the video equipment 100, or to view them on an external receiver connected via the output interface 172.

[0045] Figure 4 shows the specific configuration of the video display device 200 shown in Figure 1. The same parts are denoted by the same reference numerals, and their details are not described.

[0046] First, we will explain the case where the signal input from terminal 201 or terminal 202 is an uncompressed video baseband signal. The signal input from terminal 201 or terminal 202 is input to the encryption / decryption circuit 211 via the input / output interface 210. The encryption / decryption circuit 211 corresponds to the encryption of the encryption circuit 171 shown in Figure 2, and decrypts what has been encrypted by the encryption circuit 171. The decrypted signal is input to the demultiplexing circuit 250, and the video signal and audio signal are input to the signal processing circuits 251 and 252, respectively. The signal processing circuit 251 performs scan line conversion and resolution conversion to match the number of pixels that can be displayed on the display 260. The signal processing circuit 252 blanks the video signal and expands the time axis of the audio signal which has been time-compressed and multiplexed, and further performs lip-sync adjustment and sound quality adjustment as needed. The output signals from the signal processing circuits 251 and 252 are input to the display 260 and audio output device 270, respectively, and viewed.

[0047] Next, we will explain the case where a compressed video signal is input from terminal 201 or terminal 202. The purpose of inputting a compressed signal is to store that video signal in the storage device 230 built into the video display device 200.

[0048] Signals input from terminal 201 or terminal 202 are input to the encryption / decryption circuit 211 via the input / output interface 210. The encryption / decryption circuit 211 corresponds to the encryption of the encryption circuit 171 shown in Figure 2, and decrypts what has been encrypted by the encryption circuit 171. The decrypted signal is input to the encryption / decryption circuit 240. The encryption / decryption circuit 240 reads the copy control information of the content to be stored and performs encryption processing for storage accordingly. The encrypted signal is input to the storage device 230 and stored in a compressed state.

[0049] When viewing a compressed signal input from terminal 201 or terminal 202 while accumulating it, the decrypted signal corresponding to the compressed signal is first input from the encryption / decryption circuit 240 to the inverse multiplexing circuit 241. Subsequently, the inverse multiplexing circuit 241 separates the compressed video signal and audio signal. The separated video and audio signals are decompressed by the decompression circuits 242 and 243, respectively, and returned to baseband before being input to the signal processing circuits 251 and 252, respectively. The same process continues, with the signals being input to the display 260 and audio output device 270 for viewing.

[0050] To play and view content stored in the storage device 230, the title of the content stored in the storage device 230 is displayed on the display 260, the user selects the content, and the signal of the selected content is input from the storage device 230 to the encryption / decryption circuit 240. The encryption / decryption circuit 240 decrypts the encryption of the signal of the selected content, inputs it to the inverse multiplexing circuit 241, and the content can be viewed by processing it in the same manner.

[0051] Similarly, content stored in memory 221 can also be played back. Similar to playing back content stored in storage device 230, the user selects the content they wish to view from memory 221 and inputs the selected content to the encryption / decryption circuit 240 via the memory interface 220 and signal processing circuit 224. The signal processing circuit 224 performs the necessary processing to read the content from memory 221, compressing and multiplexing the video and audio signals, and inputting them to the encryption / decryption circuit 240. Subsequent signal processing is the same as when reading content from storage device 230.

[0052] In addition, content can be stored in the memory 221, similar to how it is stored in the storage device 230. While a detailed explanation of the processing in this case is omitted, the content encrypted by the encryption / decryption circuit 240 is stored in the memory 221 via the signal processing circuit 224 and the memory interface 220.

[0053] The same processing is performed when viewing or storing content transmitted wirelessly. The compressed content transmitted wirelessly is input to the encryption / decryption circuit 240 via the wireless interface 222 and signal processing circuit 224. The encryption / decryption circuit 240 decrypts the encryption required for wireless transmission. Subsequent processing is the same as when playing back from the storage device 230.

[0054] Even when an uncompressed baseband signal is input from terminal 201 or terminal 202, content can be efficiently stored in the storage device 230 and memory 221. The operation in this case will be described below.

[0055] Content input from terminal 201 or terminal 202 is separated into video and audio signals via the input / output interface 210, encryption / decryption circuit 211, and inverse multiplexing circuit 250. The separated video and audio signals are input to compression circuits 281 and 282 via the duplication control circuit 280. The duplication control circuit 280 reads the duplication control information multiplexed onto the input content and determines whether duplication is permitted. The duplication control information can be applied by assigning bits to specified portions, or by using digital watermarking technology to multiplex onto the video or audio information itself.

[0056] The compression circuit 281 compresses the video signal using a compression method such as MPEG2, MPEG4, or AVC / H.264. The compression circuit 282 compresses the audio signal using a compression method such as MPEG Audio. The compressed video and audio signals are input to the multiplexing circuit 283, multiplexed, and then input to the encryption / decryption circuit. They can then be stored in the storage device 230 and memory 221 in the same manner. This allows for efficient long-duration recording of content in accordance with copyright information.

[0057] So far, this embodiment has mainly described the case in which video signals and audio signals output from video equipment 100 are transmitted to video display device 200. Furthermore, this embodiment will now be described using Figure 6 in the case in which two video equipment devices 100 are connected to each other. In Figure 6, video equipment 1 and video equipment 2 are both composed of portable video equipment 100 such as mobile phones and digital cameras, and their respective terminals 101 are connected by a bidirectional interface connection cable 10. With this configuration, content such as movies received by video equipment 1 from the mobile phone base station antenna 20 can be transmitted to video equipment 2 via the connection cable 10, and the content can be displayed using the display device 160 in video equipment 2 or output as audio using the audio output device 161 in video equipment 2. In addition, when transmitting content stored in the storage device 130 in video equipment 1, the desired content is read from the storage device 130 based on the content of the control signal from video equipment 2, and the encryption / decryption circuit 140 decrypts the encryption. Then, the encryption circuit 171 performs the necessary encryption processing for external transmission, and the signal is output via interface 172 and terminal 101. The control signals from video device 2 at this time include mutual authentication signals to confirm that video device 1 and video device 2 are legitimate devices, synchronization control signals to synchronize signal processing, a transmission request signal, and an identification signal indicating that it is video device 1. Control signals are also transmitted from video device 1 to video device 2 as needed.

[0058] The signals transmitted and received between video equipment 1 and video equipment 2 may not only be signals received from the mobile phone base station antenna 20, but also signals received by the broadcast receiver 180, or content stored on the storage device 130 or content on the memory 121.

[0059] Video equipment 1 and video equipment 2 are, for example, the same video equipment 100. These video equipment devices are connected to each other by a bidirectional interface as described above. Video equipment 1 may send video and audio information to video equipment 2, and conversely, video equipment 2 can send video and audio information to video equipment 1. Here, the direction in which information is sent from video equipment 1 to video equipment 2 is defined as "uplink," and the direction in which information is sent from video equipment 2 to video equipment 1 is defined as "downlink." Of course, the opposite directions may also be called "uplink" and "downlink," respectively. The bidirectional interface connecting video equipment 1 and video equipment 2 has asymmetrical transmission rates for uplink and downlink, meaning that the transmission rates are different for each. When sending broadband video and audio information in the uplink direction, i.e., from video equipment 1 to video equipment 2, a narrowband control signal (compared to video and audio) is sent from video equipment 2 to video equipment 1. Conversely, when sending broadband video and audio information in the downstream direction, i.e., from video device 2 to video device 1, a narrowband control signal is sent from video device 1 to video device 2. Therefore, the transmission rate is set higher for the direction of transmitting broadband video and audio, while the transmission rate is set lower for the direction of transmitting narrowband control signals. In this embodiment, since information and signals of different bandwidths are transmitted upstream and downstream between multiple different video devices, it is possible to use both video signals that require broadband transmission and control signals that do not require narrowband transmission simultaneously within a limited frequency band, thereby improving the efficiency of radio wave usage. It should be noted that the control signal is not transmitted from only one device, but is also transmitted from the other device as needed.

[0060] Figure 7 is a configuration diagram of the first embodiment in which the video display device 200 and the video equipment 100 are connected wirelessly. In Figure 7, for the sake of simplicity of explanation, only the input / output interface 210 and interface 172 are shown. Thus, the bidirectional interface connecting video equipment is not limited to wired cables, but may also be configured wirelessly. In this case, the degree of freedom in the placement of each device is increased.

[0061] Figure 8 is an explanatory diagram of a wireless connection between a video device 100 and a video display device 200. In Figure 8, the video device 100 and the video display device 200 are the same as those described in Figures 1 and 2, respectively. For the sake of simplicity, in Figure 8, only the interface circuit 172 is shown for the video device 100, and other configuration requirements are not illustrated. Similarly, only the input / output interface 210 is shown for the video display device 200, and other configuration requirements are not illustrated. Here, both the interface circuit 172 and the input / output interface 210 are bidirectional interfaces, and as in the example above, the transmission rates for uplink and downlink are asymmetric. In Figure 8, the channels between antennas 81 and 84, and between antennas 82 and 85, are for bidirectional transmission of video signals, audio signals, and control signals indicating copyright protection and copy restriction conditions for content, respectively. In contrast, the channel between antennas 83 and 86 is for transmitting inter-device control signals. Furthermore, bit selection circuits 811 and 812 receive video signals, audio signals, control signals indicating copyright protection and reproduction restriction conditions for content, and inter-device control signals. Regarding the modulation / demodulation methods described above, the QPSK modulation / demodulation method has higher tolerance to transmission errors compared to the 64QAM modulation / demodulation method. On the other hand, in terms of transmission efficiency, the 64QAM modulation / demodulation method is more efficient than the QPSK modulation / demodulation method. Here, we will explain the case where video equipment 100 sends video, audio, and control signals indicating copyright protection and reproduction restriction conditions for related content to video display device 200. Here, the direction in which information is transmitted from video equipment 100 to video display device 200 is referred to as upstream, and conversely, the direction in which information is transmitted from video display device 200 to video equipment 100 is referred to as downstream.

[0062] In order for the video equipment 100 to transmit information, it first uses a carrier detection circuit (not shown) to check whether the channel to be used is already occupied by another device. This carrier detection is performed by detecting whether a carrier exists in a predetermined frequency band for a predetermined period of time. If the carrier detection circuit detects that another device is using the channel, it waits for a while and then checks the channel's availability again. After that, if it detects that the channel is no longer being used by another device, it notifies the microprocessor 115 of the video equipment 100 that the channel is now free. The microprocessor 115 outputs a channel usage request signal from the QPSK modulation / demodulation circuit 803 as an inter-device control signal to secure the right to use the channel. Next, the microprocessor 115 outputs a transmission request signal to the bit selection circuit 811. The error control circuit 843 adds error control bits for error detection and correction to this transmission request signal and sends it to the QPSK modulation / demodulation circuit 803. The QPSK modulation / demodulation circuit 803 performs QPSK modulation and transmits a wireless signal to the video display device 200 via the antenna 83. Meanwhile, the video display device 200 receives the wireless signal via the antenna 86, modulates it using the QPSK modulation / demodulation circuit 806, and outputs an inter-device control signal by performing error detection and correction control using the error control circuit 847, which it then transmits to the bit selection circuit 812.

[0063] The microprocessor in the video display device 200 decodes the received inter-device control signals and receives a transmission request signal from the video device 100, along with device category information about the video device 100 (information to identify its category, such as whether it is a display device or a recording device), and the device identification number of the video device 100. The display screen of the video display device 200 shows whether or not to connect to the video device 100. Based on this display, the user issues an instruction to authorize the connection using an input device such as the remote control of the video display device 200. After this, the video device 100 and the video display device 200 exchange device category information, identification numbers to identify each other's devices, and other information to ensure compliance with copyright protection and reproduction restrictions for the content. If there are no problems, the connection between the two devices is permitted. However, if the devices are input-only devices or output-only devices, or if connecting them is meaningless, or if it violates copyright protection or reproduction restrictions for the content, the connection process is canceled, and a message to that effect is displayed on each device. The following explains the case where there are no problems with copyright protection or reproduction restrictions for the content.

[0064] From the video signal, audio signal, and control signals indicating copyright protection and reproduction restriction conditions for the related content input to the interface circuit 172, two bits are selected from the MSB of the video signal. Error control circuit 841 adds error detection and correction control bits to these two bits and sends them to the QPSK modulation / demodulation circuit 801. The QPSK modulation / demodulation circuit 801 then performs QPSK modulation on this signal and transmits a wireless signal from antenna 81. For the remaining bits from the 3rd to the 8th, error control circuit 842 adds error detection and correction control bits and sends them to the 64QAM modulation / demodulation circuit 802. The 64QAM modulation / demodulation circuit 802 then performs 64QAM modulation on this signal and transmits a wireless signal from antenna 82.

[0065] In the video display device 200, the QPSK modulation / demodulation circuit 804 demodulates the signal received by the antenna 84 using QPSK, performs error control using the error control circuit 845, and then outputs the upper two bits of the video signal to the bit control circuit 812. For the remaining signal received by the antenna 85, the 64QAM modulation / demodulation circuit 805 demodulates it using 64QAM, performs error control using the error control circuit 846, and then outputs it to the bit control circuit 812.

[0066] Here, we will explain the inter-device control signals. When sending an inter-device control signal downstream, i.e., from the video display device 200 to the video device 100, the bit selection circuit 812 modulates the signal via the error control circuit 847 using the QPSK modulation / demodulation circuit 806 and outputs it from the antenna 86. The video device 100 receives this signal with the antenna 83, modulates it using the QPSK modulation / demodulation circuit 803 via the QPSK modulation / demodulation circuit 83, performs error detection and correction using the error control circuit 843, and then transmits it to the bit selection circuit 811. Conversely, when sending an inter-device control signal upstream, i.e., from the video device 100 to the video display device 200, the bit selection circuit 811 modulates the signal via the error control circuit 843 using the QPSK modulation / demodulation circuit 803 and outputs it from the antenna 83. The video display device 200 receives this signal with the antenna 86, demodulates it using the QPSK modulation / demodulation circuit 806, and then performs error detection and correction using the error control circuit 847 before transmitting it to the bit selection circuit 812. This method has the effect of reducing malfunctions in inter-device control signals, which are important for building the system, even in noisy environments.

[0067] In this embodiment, the upper two bits of the digital signal can be transmitted at a low transmission rate but with excellent noise immunity. In other words, by taking advantage of the fact that the upper bits of the video signal have a greater impact on image quality, the two bits from the MSB of the video signal are extracted sequentially, and a transmission path using QPSK modulation is assigned to this information to minimize image quality degradation. Incidentally, in systems where audio information is more important than video information, it is also possible to assign the important (e.g., upper) two bits of the audio signal to a transmission path using QPSK modulation.

[0068] Furthermore, when humans perceive images, there is a tendency for high-frequency components to be less noticeable than low-frequency components in both the horizontal and vertical frequency components of the screen. Also, the human eye tends to have difficulty keeping up with fast-moving objects within the screen. Utilizing these tendencies, the horizontal frequency component of the screen may be divided into low-frequency and high-frequency components, with QPSK modulation used for the low-frequency component and 64QAM modulation used for the high-frequency component. This makes it possible to improve noise immunity for important information within a limited transmission bandwidth while ensuring overall transmission capacity. Similarly, the vertical frequency component of the screen may also be divided into low-frequency and high-frequency components, with QPSK modulation used for the low-frequency component and 64QAM modulation used for the high-frequency component. This also makes it possible to improve noise immunity for important information within a limited transmission bandwidth while ensuring overall transmission capacity. Furthermore, it is possible to combine the handling of frequency components in the horizontal and vertical directions of the screen to further improve noise immunity for desired important information.

[0069] In the above explanation, the error control circuits 841, 842, and 843 were described as adding error control information to each bit input to them. However, the bits input to the error control circuits 841, 842, and 843 may be treated as a single word, and error control information may be added to this single word. This configuration simplifies the error control circuits and makes them easier to construct.

[0070] With the configuration shown in Figure 8, for example, multiple still images captured by video equipment 1 can be switched at a predetermined interval, for example every second, and transmitted to the video display device 200 or video equipment 2, and the transmitted multiple still images can be displayed on the video display device 200 or video equipment 2. The video display device 200 or video equipment 2 sends a video request signal to video equipment 1 to send an image, and based on this video request signal, video equipment 1 switches between multiple still images and transmits the still image to the video display device 200 or video equipment 2. With this configuration, if the video display device 200 or video equipment 2 cannot reproduce the image, the video request signal can be sent to video equipment 1 again and repeated until the image is received correctly. In this case as well, since the video request signal uses QPSK modulation, it has excellent noise immunity.

[0071] An embodiment for acquiring an image from video equipment 1 using such a video request signal and displaying it on a display device will be described with reference to Figure 10. This embodiment will be described using the case where multiple still images captured by video equipment 1 are switched and displayed on the video display device 200 as an example, but the same method can be used when displaying on video equipment 2.

[0072] Figure 10 shows an embodiment of a display device configured to display still images from video equipment 1, in which a television display device equipped with a high-definition HD display 1002 is used as the display device. In Figure 10, video equipment 1020 is specifically a digital camera, mobile phone, game console, personal media player, etc. In this embodiment, still images are transmitted from this video equipment 1020 to the video display device 200 (television display device) via two interfaces. One is HDMI for transmitting still images as baseband video information, and the other is USB for transmitting still images as compressed video information. Here, the compressed video information transmitted via USB is assumed to be compressed in JPEG format.

[0073] First, let's explain the configuration and operation of the video device 1020. When transmitting a still image of compressed video information, the video device 1020 reads a still image compressed in JPEG format from a memory 1018, which is composed of, for example, flash memory. Without performing any signal processing such as decompression, it supplies this image from the USB mass storage interface circuit 1019 to the USB terminal 1012, which is the first input of the video display device 200.

[0074] On the other hand, when transmitting a still image of baseband video information, the video device 1020 first reads the still image from the memory 1018. Since this still image is compressed in JPEG format, the signal processing circuit 1016 performs signal processing to decompress the compressed image and generates baseband video information. This baseband video information is transmitted from the HDMI interface circuit 1017 to the HDMI terminal 1005, which is the second input of the video display device 200.

[0075] Next, the configuration and operation of the video display device 200 will be described. A still image of compressed video information input to the first input section, the USB terminal 1012, is supplied to the image processing circuit 1006 via the USB host interface circuit 1011. The image processing circuit 1006 includes a JPEG data file access circuit 1010, a JPEG decoding circuit 1009, a resize / effect addition circuit 1008, and an image stream signaling circuit 1007. The still image input to the USB terminal 1012 is supplied to the JPEG decoding circuit 1009 via the JPEG data file access circuit 1010, where the still image compressed in JPEG format is decoded, i.e., decompressed. The decompressed still image is then modified by the resize / effect addition circuit 1008 to change its display size (number of pixels in the horizontal and vertical directions) and to apply desired effect processing (e.g., rotation). The still image, after being resized and processed by the resize / effect addition circuit 1008, is converted into a displayable image signal by the image stream signal conversion circuit 1007 and supplied to the HD display 1002 via the switching circuit 1003. As a result, the compressed still image input via the USB host interface circuit 1011 is displayed on the screen of the HD display 1002.

[0076] In this embodiment, a LAN terminal 1014 is provided as a first input unit to which compressed video information is input, and which can be connected to various networks 1015 such as wireless LAN, wired LAN, and the internet. Therefore, in this embodiment, compressed video can be acquired not only through the USB interface but also through the network 1015. The compressed video information input to the LAN terminal 1014 is input to the image processing circuit 1006 via the LAN / DLNA (Digital Living Network Alliance) interface circuit. The processing in this image processing circuit 1006 is the same as the processing for compressed video information input via the USB terminal 1012 described above, so a redundant explanation is omitted here.

[0077] Meanwhile, the still image of the baseband video information input to the second input, the HDMI terminal 1005, undergoes a predetermined decoding process (decryption process) by the HDMI interface / decode circuit 1004. The decrypted still image is supplied to the HD display 1002 via the switching circuit 1003, and the still image is displayed on the screen of the HD display 1002.

[0078] The switching circuit 1003 selects either a still image input to the HDMI terminal 1005 or a still image input to the USB terminal or LAN terminal 1014 and supplies it to the HD display 1002. This is controlled, for example, by the user's operation of the remote control for the video display device 200. Therefore, the user can choose to display compressed video information or baseband video information on the HD display 1002 according to their preference.

[0079] In the above embodiment, HDMI and USB interfaces are used as interfaces for connecting to the video equipment 1020, but of course, other standard interfaces may also be used.

[0080] Before describing the operation of this embodiment based on the video request signal, a supplementary explanation of the HDMI interface is provided. Figure 16 shows an example configuration of an HDMI interface, which mainly consists of a transmitter and a receiver. The transmitter includes a transmitter 1601 and a transmitter control unit 1603 that controls the transmitter 1601. The transmitter 1601 is configured to encode video signals (Y, Pb, Pr) and audio signals and output them to the receiver 1604. Furthermore, the transmitter 1601 includes a TMDS encoding circuit 1602, which converts the video signals (Y, Pb, Pr) and audio signals into serial video data and serial audio data, respectively. On the other hand, the receiver includes a receiver 1604 and a transmitter control unit 1606 that controls the receiver 1604. The receiver 1604 decodes the video data and audio data sent from the transmitter 1601 using a TMDS decoder 1605 and reproduces the baseband video data and audio data. The CEC line 1607 constitutes an equipment control line that transmits control signals for the equipment, and display specification information called DDC is transmitted via the DDC line 1608. The receiving side also sends an HPD (Hot Plug Detect) signal 1609 to the transmitting side, indicating that the transmitting and receiving equipment are connected.

[0081] Figure 17 shows an example of the remote control code format transmitted via the CEC line 1607 described above. As shown in Figure 17, the remote control code is 48 bits long and includes a 16-bit manufacturer code to identify the manufacturer and a 12-bit device code to identify the device, such as the model number or serial number. The format of the remote control code may be other than that shown in Figure 17. Also, the length of the remote control code is not limited to 48 bits and may be a different bit length. Next, an example of how to transmit this remote control code via the CEC line will be explained with reference to Figure 18. First, when the video equipment and the display device are connected, the display device sends an HPD signal 1609 to the video equipment indicating that the two devices are connected. Then, the display device 200 reads the manufacturer code and device code of the video equipment via the CEC line 1607 of the HDMI cable. The read manufacturer code and device code are then stored in the display device 200 along with the receiving interface number. These manufacturer code and device code may be stored in the memory of the display device 200, for example, in a microcontroller not shown. If other HDMI cables are connected, the same process is performed on those HDMI cables as well, and the corresponding manufacturer code and device code are recorded on the display device along with the receiving interface number. The manufacturer codes and device codes read in this way are stored as a table as shown in Figure 19. With this configuration, for example, even if the manufacturers of the display device 200 and the video equipment 1020 connected to each other are different, communication between the two can be established by referring to the stored manufacturer codes and device codes, allowing the video equipment 1020 to control the display device 200 or to transmit display specification information (DDC) from the display device 200 to the video equipment 1020.

[0082] Returning to Figure 10, the operation of this embodiment based on the video request signal will be explained. In Figure 10, the user operates an input device such as a remote control or keyboard of the video display device 200, causing the input device to output a control command to switch the display mode for displaying the still images described above. In accordance with this control command, the JPEG data file access circuit 1010 of the video display device 200 transmits a video request signal to the external video device 1020 via the USB host interface circuit 1011 and the USB terminal 1012, instructing it to output a still image, which is compressed video information. In other words, in this example, the JPEG data file access circuit 1010 functions as a transmitter for sending the video request signal to the external video device 1020. This video request signal is transmitted from the video display device 200 to the video device 1020 at a predetermined interval (for example, every second). Upon receiving this video request signal, the video device 1020 outputs the still image data recorded in the memory 1018 via the USB mass storage interface circuit 1019. The USB host interface circuit 1011 receives this still image data via the USB terminal 1012. Then, the JPEG decoding circuit 1009 decodes the read JPEG data and restores it to the original image data. Next, the resize and effect addition circuit 1008 resizes and applies effects, and the image stream signal conversion circuit 1007 converts it into an image signal for display and displays it on the HD display 1002.

[0083] By repeating the process from transmitting the video request signal described above to converting the display image signal by the image stream signaling circuit 1007 at predetermined intervals (e.g., 1 second), it is possible to perform an image display method called a slideshow, which displays multiple still images acquired from the video equipment 1020 by switching them at predetermined intervals. Of course, this time interval can be other than 1 second, and this interval can be changed as appropriate by the user using the input device described above. Furthermore, the video request signal may be output repeatedly until all still images have been read from the video equipment 1020, or a predetermined period (e.g., 10 seconds to 1 minute) may be set, and the video request signal may be transmitted at predetermined intervals within that predetermined period.

[0084] Furthermore, it is also possible to send the above-mentioned video request signal from the microcontroller (not shown) of the video display device 200 to the video device 1020 via the HDMI interface / decode circuit 1004 and the HDMI terminal 1005. In this case, since the HDMI interface is an interface for transmitting moving images as a transmission format, unless there is specific control, moving images that do not change over time are transmitted.

[0085] First, the user operates an input device such as a remote control or keyboard of the video display device 200, causing the input device to output a control command to enter the above display mode. In accordance with this control command, the HDMI interface / decode circuit 1004 transmits a video request signal to the video device 1020 via the CEC line in the HDMI terminal 1005. In other words, in this example, the HDMI interface / decode circuit 1004 functions as a transmitter for sending a video request signal to the external video device 1020. This video request signal is transmitted from the video display device 200 to the video device 1020 at predetermined periodic intervals (for example, every second) for a few seconds to one minute, similar to the example described above. In response, the video device 1020 converts the still image data recorded in the memory 1018 into a signal format that can be displayed as a moving image using the signal processing circuit 1016, and outputs it via the HDMI interface circuit 1017. The video display device 200 receives this data via the HDMI terminal 1005 and the HDMI interface circuit / decode circuit 1004, and displays it on the HD display. By repeating this process at predetermined intervals, it becomes possible to display images in a slideshow format. Naturally, this time interval can be configured to be changed as appropriate by the user, as described above. Furthermore, the video request signal may be repeatedly output until all still images have been read from the video equipment 1020, or the video request signal may be transmitted at predetermined intervals within a predetermined period, as described above.

[0086] Furthermore, while the above explanation has focused on how to display image information from the video device 1020 on the video display device 200, a similar slideshow display method is also possible when the image information resides on the network 1015. In this case, the JPEG data file access circuit 1010 of the video display device 200 receives a control command from the input device and transmits it to the network 1015 via the LAN / DLNA interface circuit 1013 and the LAN terminal 1014. In this case, the network address (e.g., IP address) of the video device connected to the network is added to the video request signal. The video signal corresponding to the address added to this video request signal receives the video request signal and transmits still image data as compressed video information. This still image data is input via the LAN terminal 1014 and the LAN / DLNA interface circuit 1013 and supplied to the JPEG decoding circuit 1009. The subsequent processing is the same as the processing for still images input to the USB terminal 1012 described above, so redundant explanations are omitted here.

[0087] In this embodiment, a LAN terminal 1014 and a LAN / DLNA interface circuit 1013 are provided to realize this network functionality. However, it is also possible to extend the functionality by adding an HDMI interface or a USB interface.

[0088] Figure 11 shows the configuration of another embodiment according to the present invention. In Figure 11, components identical to those in Figure 10 are numbered the same as in Figure 10. The difference between the configuration in Figure 11 and that of Figure 10 is that the signal paths from the USB terminal 1012 and the LAN terminal 1014 have been removed from the display device 200 in Figure 10. Another difference is that in the configuration of the video device 1020, the USB mass storage interface circuit 1019 has been replaced with a PTP (Protocol for connecting a digital camera and a PC, etc., via USB to transfer and control images) control circuit 1101 and a LAN interface circuit 1102. In terms of operation, the HDMI terminal path works similarly in Figure 10 and Figure 11, and a slideshow is possible. Using the configuration in Figure 11 simplifies the configuration of the display device 200 and eliminates the need for complicated connections, thus improving user convenience. In other words, this embodiment can also be applied to a configuration that only has a first input unit, that is, a configuration that displays still images of bandwidth video information. In this example, only one HDMI interface is provided, but two or more interfaces may be included.

[0089] Here, using Figure 10, we will explain another display mode for multiple still images captured by the video equipment 1 on the video display device 200. This display mode involves simultaneously displaying multiple still images in reduced size on a single screen of the HD display 1002.

[0090] In Figure 10, the JPEG data file access circuit 1010 of the video display device 200 sends a request to the video device 1020 to acquire a still image via the USB host interface circuit 1011 and the USB terminal 1012. In response, the video device 1020 outputs still image data, which is compressed video information recorded in memory 1018, via the USB mass storage interface circuit 1019. The USB host interface circuit 1011 reads this still image data via the USB terminal 1012. Subsequently, the JPEG decoding circuit 1009 JPEG decodes the read JPEG data and restores it to the original image data. Then, the resize and effect addition circuit 1008 resizes and applies effects, and temporarily saves it as an image corresponding to display position 1 in Figure 12. Similarly, the JPEG data file access circuit 1010 sends a request to the video device 1020 to acquire the next still image via the USB host interface circuit 1011 and the USB terminal 1012. In response, the video device 1020 outputs the next compressed video information, which is still image data, recorded in memory 1018, via the USB mass storage interface circuit 1019. The USB host interface circuit 1011 reads this still image data via the USB terminal 1012. Subsequently, the JPEG decoding circuit 1009 decodes the read JPEG data and restores it to the original image data. Then, the resize and effect addition circuit 1008 resizes and applies effects, and temporarily saves it as an image corresponding to display position 2 in Figure 12. By repeating this process from video acquisition request to temporary image saving, for example, 12 times, it is possible to display multiple still images together, called thumbnail display, as shown in Figure 12. This process is performed, for example, by sending 12 video acquisition requests to the video device 1020 within a predetermined time (for example, less than 1 second).

[0091] If the video device 1020 contains 12 or more still images, thumbnails will be displayed in groups of 12. This display method allows users to view multiple images simultaneously, making it easier to distinguish between differences in color and subtle scene variations, thus improving convenience.

[0092] Here, to make the operation easier to understand, we connected one video device 1020, but it is also possible to connect two video devices 1020, so it is possible to view images from two video devices side by side, for example, six frames each. Doing so allows you to check for differences in color and brightness due to variations between the two video devices 1020 and differences in shooting conditions, and has the effect of making it easy to select the desired image from the images of the two video devices.

[0093] This display function can also be implemented using the configuration shown in Figure 11. Both Figure 10 and Figure 11 have the same effect in operation, allowing for the combined display of multiple still images captured by the video device 1. Using the configuration in Figure 11 simplifies the configuration of the display device 200 and eliminates the need for complex connections, thus improving user convenience. In this case, memory is required to combine multiple small images. Alternatively, multiple small images may be combined beforehand on the memory 1018 on the video device 1020 before being sent to the video display device 200, or a memory (not shown) may be configured after the HDMI interface circuit and decoding circuit 1004, and the small images may be composed in this memory. Both configurations have the same effect as Figure 10.

[0094] In the above explanation, the number of still images displayed simultaneously was set to 12, but as shown in Figure 13, it is also possible to display them in two rows and two columns. Similarly, as shown in Figure 14, it is also possible to display them in two rows and two columns. Using the divisions shown in Figures 13 and 14, since the resolution of the HD display 1002 is 1080 x 1920, the resolution of each small screen becomes approximately 300 x 500, making it easier to discern differences in images. Also, while screen flicker may occur when the small screen itself is small, this flicker can be reduced by using the divisions shown in Figures 13 and 14. On the other hand, using the division shown in Figure 12, when inputting video from a digital camera, the aspect ratio of that video is approximately 4:3, so it has the effect of being efficiently arranged and displayed on the HD display 1002 which has an aspect ratio of 16:9. Even when displaying them side by side as in Figures 13 and 14, although there will be some areas that are not displayed, almost the same effect can be obtained.

[0095] Incidentally, each image stored in the memory 1018 of the video device 1020 has attribute information added to it, such as image rotation information and accidental erasure prevention lock information to prevent accidental erasure. In this embodiment, this attribute information is sent from the video display device 200 to the video device 1020 via the HDMI terminal 1005 and stored in the memory 1018 by operation from the remote control or keyboard of the video display device 200. Figure 15 shows an example of a management table of attribute information recorded on the memory 1018. As shown in Figure 15, the video display device 200 can add and store attribute information regarding whether erasure lock is enabled and the rotation angle for each of the multiple still images stored in the memory 1018 of the video device 1020 based on a signal from the video display device 200. With this configuration, since the device that the user directly controls is always the video display device 200, even if any video device 1020 is connected, accidental erasure prevention lock control and image rotation control can be performed with the same operation, eliminating the need to remember the complex operation for each video device 1020, thus improving convenience.

[0096] Although the encryption process is not described in detail in the embodiment shown in Figure 8, the encryption circuit 171 and the interface circuit 172 can be combined to perform the process as shown in Figure 9. Figure 9 shows an example of a configuration for performing encryption processing in the system shown in Figure 8. The system in Figure 9 consists of encryption / decryption circuits 821-826, interface circuits 830 and 831 that include encryption processing, and error control circuits 841, 842, 843, 845, 846, and 847.

[0097] In the example shown in Figure 9, similar to the example in Figure 8, a bit selection circuit 811 selects a predetermined bit, and each bit is error-controlled by error control circuits 841 and 842. After that, the bit is encrypted by encryption / decryption circuits 821 and 822 and input to the QPSK modulation / demodulation circuit 801 and 64QAM modulation / demodulation circuit 802. The demodulated signals from the QPSK modulation / demodulation circuit 804 and 64QAM modulation / demodulation circuit 805 are input to encryption / decryption circuits 824 and 825, where they are encrypted and decrypted, and then bit-combined by the bit selection circuit 812. This processing enables signal processing according to importance, making it less prone to errors for important information, and thus enabling efficient transmission with less image quality degradation.

[0098] Furthermore, by combining reversible codes with the encryption / decryption circuits 821-826, transmission efficiency can be further improved. For example, in the example shown in Figure 9, before encryption processing is performed by the encryption / decryption circuits 821-823, the bits to be transmitted are reduced using, for example, a reversible arithmetic code based on statistical properties, and then encryption is performed. In the video display device 200, after encryption and decryption are performed by the encryption / decryption circuits 824-826, decryption is performed using a reversible code corresponding to the encryption / decryption circuits 821-823, error detection and correction are performed by the error control circuits 845-847, and bit synthesis is performed by the bit selection circuit 812. By combining reversible codes, the transmission rate of the information to be transmitted can be reduced, making transmission even more efficient.

[0099] Furthermore, let me provide some additional information regarding encryption. By using AES 128-bit encryption processing for all encryption circuits, it is possible to achieve a high level of protection. In addition, by using AES 128-bit encryption processing for content encryption circuit 821 and DES encryption processing for other encryption circuits, it becomes easier to configure the system while maintaining a balance between content protection, which is crucial for the system, and processing efficiency.

[0100] Furthermore, the system may be configured to switch between baseband signal transmission and compressed signal transmission according to inter-device control signals. With this configuration, when transmitting a compressed signal in response to requirements such as content protection, transmission using QPSK modulation enables transmission with excellent error tolerance in the transmission path. When transmitting a baseband signal, 64QAM modulation enables transmission with high transmission efficiency.

[0101] The operation of the video equipment 100 and the video display device 200 in Figure 9 is basically the same as the operation of the video equipment 100 and the video display device 200 in Figure 8. In order for the video equipment 100 to transmit, it first uses a carrier detection circuit (not shown) to check whether the channel to be used is already occupied by another device. This carrier detection is performed by detecting whether a carrier exists in a predetermined frequency band for a predetermined period of time. If the carrier detection circuit detects that another device is using the channel, it waits for a while and then checks the channel availability again. After that, if it detects that the channel is not being used by another device, it notifies the microprocessor 115 of the video equipment 100 that the channel is free. The microprocessor 115 outputs a channel usage request signal from the QPSK modulation / demodulation circuit 803 as an inter-device control signal to secure the right to use the channel. Next, the microprocessor 115 outputs a transmission request signal to the bit selection circuit 811.

[0102] The error control circuit 843 adds error control bits for error detection and correction to this transmission request signal, encrypts it using the encryption / decryption circuit 823, and sends it to the QPSK modulation / demodulation circuit 803. The QPSK modulation / demodulation circuit 803 performs QPSK modulation and transmits the wireless signal to the video display device 200 via the antenna 83. Meanwhile, the video display device 200 receives the wireless signal via the antenna 86, demodulates it using the QPSK modulation / demodulation circuit 806, and decrypts it using the encryption / decryption circuit 826. The error control circuit 847 performs error detection and correction control on this decrypted signal, outputs an inter-device control signal, and transmits it to the bit selection circuit 812. The microprocessor in the video display device 200 decodes the received inter-device control signal and receives the transmission request signal from the video device 100, along with device category information related to the video device 100 (information to identify the category, such as whether it is a display device or a recording device), and the device identification number of the video device 100. The display screen of the video display device 200 shows whether or not to connect to the video equipment 100. Based on this display, the user issues a command to authorize the connection using an input device such as the remote control of the video display device 200. After this, the video equipment 100 and the video display device 200 exchange information such as each other's device category information and identification numbers to identify each other's devices, and exchange information to comply with copyright protection and reproduction restriction conditions of the content. If there are no problems, the connection between the two devices is permitted. However, if the devices are input-only devices or output-only devices, or if there is no point in connecting them, or if there is a violation of copyright protection or reproduction restriction conditions of the content, the connection process is canceled, and a message to that effect is displayed on each device. In this way, if there are no problems with copyright protection or reproduction restriction conditions of the content, the connection is made, and video and audio are transmitted from the video equipment 100 to the video display device 200. [Examples]

[0103] Figure 5 shows a second embodiment of the present invention, illustrating another configuration of the video display device 200 shown in Figure 1. Figure 5 is partially the same as the embodiment shown in Figure 4, and the common parts are given the same numbers, and their detailed descriptions are omitted. The video display device 200 shown in Figure 5 includes an encryption / decryption circuit 212, encryption / encryption / decryption circuits 245 and 290, compression / transcoding circuits 291 and 292, and a replication control circuit 293 which is a multiplexing circuit.

[0104] In the embodiment shown in Figure 5, when a baseband signal is input from terminal 201 or terminal 202, it operates in the same manner as in the embodiment shown in Figure 4. The compression / transcoding circuits 292 and 291 operate as compression circuits for the baseband signal. When a compressed signal is input from terminal 201 or terminal 202, the encryption necessary for transmission is decrypted by the encryption / decryption circuit 212 via the input / output interface 210, and the compressed video signal and compressed audio signal are separated by the inverse multiplexing circuit 250. Each signal is input to the duplication control circuit 290, where duplication is determined based on information indicating whether duplication is possible. If duplication is possible, the bitrate of the compressed video signal and compressed audio signal is reduced as needed by using a more efficient compression method in the compression / transcoding circuits 291 and 292. The output signals of the compression / transcoding circuits 291 and 292 are multiplexed by the multiplexing circuit 293 and input to the encryption / cryptography / decryption circuit 245. If the duplication control circuit 290 detects that duplication is permitted, the encryption / decryption circuit 245 applies appropriate encryption processing to the input signal for storage and stores it in the storage device 230 and / or memory 221. When playing back the stored signal, the encryption / decryption circuit 245 decrypts the playback signal from the storage device 230 and memory 221, and the inverse multiplexing circuit 241 separates it into a video signal and an audio signal. From there, it can be processed and viewed in the same manner as described above. When viewing while storing in the storage device 230 or memory 221, the signal from the multiplexing circuit 293 is input to the inverse multiplexing circuit 241 via the encryption / decryption circuit 245 and processed in the same manner. In this case, the transcoded image quality can be confirmed. When viewing directly without storage, the signal is input from the encryption / decryption circuit 212 to the inverse multiplexing circuit 241 via the encryption / decryption circuit 245, where it is separated into a video signal and an audio signal and processed in the same manner.

[0105] In the embodiment shown in Figure 5, even when a compressed signal is input, transcoding can be performed to efficiently store the signal at a higher compression ratio. Furthermore, this embodiment shows an example in which the signal processing means, including the compression circuits 111 and 113, are implemented using circuits. However, the above processing may also be performed by configuring various circuit elements using software means, and similar effects can be achieved in that case as well. The present invention does not limit how the signal processing is implemented. [Explanation of Symbols]

[0106] 100 Video Equipment 121, 221, 321 memory 122, 222 Wireless Interfaces 110 Imaging device 111, 113, 281, 282, 291, 292 Compression Circuit 112 Mike 114 sensors 116, 170, 283, 293 multiplex circuit Signal processing circuits 124, 150, 151, 224, 251, 252 130, 230 Storage device 140, 240, 245 Encryption / Decryption Circuits 141, 250, 241 inverse multiplex circuit 142, 143, 242, 243 expansion circuit 160 Display device 161, 270 Audio output device 171 Cryptographic Circuits 180 Broadcast receiver 200 Video Display Devices 211, 212 Cryptographic Decryption Circuits 260 displays 280 Replication Control Circuit 300 receivers

Claims

1. In a television display device, A first interface unit that allows uncompressed image information to be input from an external device via a wired connection, A second interface unit that allows compressed image information to be input via wired connection from an external device, A decompression unit capable of decompressing compressed image information input to the second interface unit, A display unit capable of displaying a first image based on uncompressed image information input to the first interface unit, or a second image based on image information obtained by decompressing compressed image information input to the second interface unit using the decompression unit, It comprises an audio output unit that outputs sound, The display unit is further configured to display received television broadcast programs. Depending on the operation of the input device of the display device, it is possible to select whether to display the first image on the display unit or the second image on the display unit. When it is selected to display the first image, based on the operation for slideshow display on the input device of the display device, The first interface unit transmits a first signal via wire to an external device to cause the external device to convert compressed image information into uncompressed image information and output it, and the display unit receives the uncompressed image information output from the external device via wire, thereby performing a slideshow display at predetermined time intervals using a plurality of first images based on the input uncompressed image information. When it is selected to display the second image, based on the operation for slideshow display on the input device of the display device, The second interface unit transmits a second signal via wire to an external device to cause the external device to output compressed image information, and the display unit receives the compressed image information output from the external device via wire, thereby performing a slideshow display at predetermined time intervals using a plurality of second images based on the image information decompressed by the decompression unit from the input compressed image information. The display unit displays an image, and the audio output unit outputs sound simultaneously. A television display device characterized by the following features.

2. A television display device according to claim 1, characterized in that a predetermined time interval for displaying a slideshow using the first image, or a predetermined time interval for displaying a slideshow using the second image, can be changed by operating the input device of the display device.

3. A television display device according to claim 1, characterized in that an image based on compressed image information input to the second interface unit can be rotated based on an operation on the input device and displayed on the display unit.

4. A television display device according to claim 1, characterized in that it enables the addition or modification of attribute information of compressed image information stored in an external device in response to an operation on the input device of the display device.

5. A television display device according to claim 1, characterized in that, in response to an operation on the input device of the display device, attribute information of compressed image information stored in the external device is added or modified, and the attribute information is transmitted from the first interface unit to the external device.

6. In a television display device, An HDMI interface unit that can input uncompressed image information from external devices, A USB interface unit that allows compressed image information to be input from an external device, A decompression unit capable of decompressing compressed image information input to the USB interface unit, A display unit capable of displaying a first image based on uncompressed image information input to the HDMI interface unit, or a second image based on image information obtained by decompressing compressed image information input to the USB interface unit using the decompression unit, It comprises an audio output unit that outputs sound, The display unit is further configured to display received television broadcast programs. Depending on the operation of the input device of the display device, it is possible to select whether to display the first image on the display unit or the second image on the display unit. When it is selected to display the first image, based on the operation for slideshow display on the input device of the display device, The HDMI interface unit transmits a second signal to an external device to cause the external device to convert compressed image information into uncompressed image information and output it, and the display unit receives the uncompressed image information output from the external device and performs a slideshow display at predetermined time intervals using a plurality of first images based on the input uncompressed image information. When it is selected to display the second image, based on the operation for slideshow display on the input device of the display device, The USB interface unit transmits a second signal to the external device to cause the external device to output compressed image information, and the display unit receives the compressed image information output from the external device. The display unit then performs a slideshow at predetermined time intervals using a plurality of second images based on the image information decompressed by the decompression unit from the input compressed image information. The display unit displays an image, and the audio output unit outputs sound simultaneously. A television display device characterized by the following features.

7. A television display device according to claim 6, characterized in that a predetermined time interval for displaying a slideshow using the first image, or a predetermined time interval for displaying a slideshow using the second image, can be changed by operating the input device of the display device.

8. A television display device according to claim 6, characterized in that an image based on compressed image information input to the USB interface unit can be rotated based on the operation of the input device and displayed on the display unit.

9. A television display device according to claim 6, characterized in that it enables the addition or modification of attribute information of compressed image information stored in an external device in response to an operation on the input device of the display device.

10. A television display device according to claim 6, characterized in that, in response to an operation on the input device of the display device, attribute information of compressed image information stored in the external device is enabled to be added or modified, and the attribute information is transmitted from the HDMI interface unit to the external device.

11. A television display device according to claim 1 or 6, characterized in that the input device for the display device is a remote control or keyboard for the display device.

12. A television display device according to claim 4 or 10, characterized in that the attribute information includes information relating to preventing the erasure of the compressed image information.

13. A television display device according to claim 4 or 10, characterized in that the attribute information includes information relating to the rotation of the compressed image information.

Images