Disc reproducing apparatus.

BACKGROUND OF THE INVENTION

Field of the Invention

0001The invention relates to a disc reproducing apparatus which can reproduce a CD-I disc on which image data and the like in addition to audio data are recorded.

Description of the Prior Art

0002There has been proposed a CD-I (CD Interactive) system in which image data (natural image, animation, computer graphics, etc.), text data, program data, and the like in addition to audio data are recorded onto a CD (Compact Disc) and which can execute the operation in an interactive manner. Since such a CD-I system has a reproducing function of characters, images, audio data, computer data, etc., it can be used in AV industrial apparatuses mainly for the purpose of audio and video fields, an electronic publishing which mainly handles characters, data base services mainly comprising information files, education and amusement which are mainly executed by interactive responses, and the like. Thus, the CD-I system is expected as a medium of a new format.

0003In the CD-I system, various specifications are predetermined so that it can widely be spread as a home-use system while keeping a compatibility. That is, in the CD-I system, a CPU of the 68000 type (microprocessor of 16 bits developed by Motorola Inc.) is used and an operating system which is fundamentally based on widespread OS9 is used as a real-time operating system which handles various kinds of files. Two trigger buttons and an X-Y device are used as an input device. Two audio and video systems are prepared as an output system. The CD-I player is constructed so that it can reproduce ordinary compact disc for a music.

0004As mentioned above, in the CD-I system, it has been predetermined to use two trigger buttons and an X-Y device as an input device and all of the operations can be executed by using the two trigger buttons and the X-Y device at a minimum. In the input device having such limited keys, however, there is a limitation in improvement of the operability. Particularly, in the case of executing the audio reproduction by the CD-I system, it is demanded that the operations can be performed in conformity with those of the conventional compact disc player for musics.

OBJECTS AND SUMMARY OF THE INVENTION

0005It is, therefore, an object of the invention to provide a disc reproducing apparatus which can improve the operability in the case of reproducing a CD-I disc or a CD-I/CD-DA disc.

0006According to an aspect of the invention, there is provided a disc reproducing apparatus for reproducing a disc on which at least image data in addition to audio data have been recorded, comprising:    means for forming a video signal on the basis of the image data;    reproducing means for reproducing the video signal;    input means for inputting control information to control the video signal reproduced; and    control means for controlling the reproduction of the video signal on the basis of the control information and for allowing input information indicative of control information which can be input to be reproduced together with the video signal by the input of the control information during the reproduction of the video signal.

0007The above, and other, objects, features and advantage of the present invention will become readily apparent from the following detailed description thereof which is to be read in connection with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

0008<ul id="ul0001" list-style="none"><li>Fig. 1 (Figs. 1A and 1B) is a perspective view showing a whole construction of an embodiment of the invention;</li><li>Figs. 2A, 2B and 3 are schematic diagrams which are used in the explanation of the specifications of a CD-I;</li><li>Fig. 4 is a block diagram showing an internal construction of the embodiment of the invention;</li><li>Fig. 5 is a flowchart which is used in the explanation of the operation of the embodiment of the invention;</li><li>Fig. 6 (Figs. 6A,6B,6C,6D) is a schematic diagram which is used in the explanation of the indication of a display in the embodiment of the invention; and</li><li>Fig. 7 (Figs. 7A and 7B) is a perspective view which is used in the explanation of a conventional CD-I system.</li></ul>

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

0009An embodiment of the invention will be described in accordance with the following order. <ul id="ul0002" list-style="none"><li>a. Construction of an embodiment</li><li>b. With respect to a CD-I format <ul id="ul0003" list-style="none"><li>b1. Data structure</li><li>b2. Writing of audio data</li><li>b3. Writing of video data</li><li>b4. Disc</li><li>b5. Hardware</li></ul></li><li>c. Internal construction of an embodiment</li><li>d. Operation of an embodiment</li><li>e. Operation when display is unnecessary</li><li>f. Operations which are executed by displaying keys onto the screen</li></ul>

a. Construction of an embodiment

0010Figs. 1A and 1B are diagrams showing a whole construction of a CD-I player to which the invention has been applied.

0011In Figs. 1A and 1B, reference numeral 1 denotes a whole CD-I player to which the invention has been applied. In order to enable the CD-I player 1 to be easily carried to the outside an LCD display 13 is integrated and the size and weight of the CD-I player 1 are reduced by realizing an IC, using chip parts, and the like. Dimensions of the entire CD-I player 1 are set to, for instance, a width of 140 mm, a length of 170 mm, and a height of 60 mm.

0012A disc driving section to rotate the disc 15 which has been set, a head driving section to move the optical head in the radial direction of the disc, and a printed circuit board to process a reproduction signal from the optical head are enclosed in the casing of the player main body portion 2 of the CD-I player 1. Further, a computer comprising a CPU of the 68000 type is enclosed in the casing.

0013A head phones jack 3, a sound volume adjusting dial 4, and a power on/off switch 5 are arranged on a front side surface 2A of the player main body portion 2. An open button 6 is arranged on a front side upper edge of the player main body portion 2.

0014A middle cover 7 is rotatably arranged on the player main body portion 2 of the CD-I player 1. By depressing the open button 6, the middle cover 7 is opened as shown in Fig. 1B. When the middle cover 7 is opened, the disc can be loaded/unloaded. A window portion 8 is formed in the middle cover 7. A transparent member is used as a window portion 8. The rotating state of the loaded disc 15 can be checked through the window portion 8.

0015An X-Y device 11 and trigger buttons 12A and 12B are arranged on a front edge surface of the middle cover 7. The X-Y device 11 can designate positions in the X and Y directions by depressing portions which are deviated from the center in the vertical and horizontal direction, respectively.

0016A pointing device such as track ball, mouse, joy-stick, or the like can be used as such an X-Y device 11.

0017An outer cover 12 is rotatably arranged over the middle cover 7. The outer cover 12 can be manually opened. The outer cover 12 can be opened to an opening/closing angle of 90° or more, and fixed to predetermined opening/closing angle of ϑ . The LCD display 13 of a size of, e.g., 4 inches is arranged on a back surface 12A of the outer cover 12. By opening the outer cover 12, the LCD display 13 is exposed as shown in the figure, thereby enabling a picture plane of the LCD display 13 to be seen. An LCD driving switch 14 is also arranged on the back surface 12A of the outer cover 12. By operating the LCD driving switch 14, the LCD display 13 can be on/off controlled.

b. With respect to a CD-I format

0019The CD-I player to which the invention has been applied can reproduce a CD-I disc, a CD-I/CD-DA disc (disc in which a CD-I format and a CD-DA format mixedly exist), and a CD-DA disc (ordinary compact disc for reproducing a music) as discs. A data format of the CD-I will now be described.

b1. Data structure

0020The CD-I records data in a format which is fundamentally based on the CD-ROM. A recording unit of the data is set to a block in a manner similar to the CD-ROM. One block is set to 2352 bytes. In the case of the disc having a diameter of 12 cm, a recording capacity of the whole CD-I disc is equal to about 640 Mbytes.

0021There are two kinds of data structures of the CD-I of a form 1 and a form 2. They correspond to a mode 1 and a mode 2 of the CD-ROM, respectively.

0022In the mode 1 in the CD-ROM, an error detection code and an error correction code are added to the data of one block, thereby enabling a strong error correction to be executed. In the mode 2 in the CD-ROM, none of the error detection code and the error correction code is added, thereby enabling a large amount of user's data to be assured.

0023In the CD-I, the form 1 and the form 2 can be designated every block and both of the forms 1 and 2 can be allowed to mixedly exist in one disc.

0024The CD-I format differs from the CD-ROM format with respect to a point that a sub-header of eight bytes is provided at the head of the user's data. Each block in which audio data, image, and data have been recorded is time-sharingly multiplexed to the sub-header on a block unit basis, and they are written twice and stored to process in a real-time manner. The sub-header comprises four items of a file number, a channel number, a sub-mode, and a data type.

0025That is, Fig. 2A shows a structure of the form 1. In the form 1, a sync (12 bytes) is provided at the head. A header (4 bytes) is subsequently provided. Further, a sub-header (8 bytes) is provided. After that, user's data (2048 bytes) is provided. An error detection code EDC (4 bytes) and a P parity (172 bytes) and a Q parity (104 bytes) for error correction are added to the user's data. In the form 1, the error correcting capability is enhanced. The form 1 is suitable in the case of handling data such as character data, program data, or the like whose errors cannot be interpolated.

0026Fig. 2B shows a structure of the form 2. In the form 2, a sync (12 bytes) is provided at the head. A header (4 bytes) is subsequently provided. Further, a sub-header (8 bytes) is provided. After that, user's data (2324 bytes) is provided and a reserve area (4 bytes) is provided. The form 2 is suitable in the case of handling data such as audio data, video data, or the like which can be interpolated.

0027As shown in Fig. 3, the sub-header which is added to the head of the user's data comprises a file number (2 bytes), a channel number (2 bytes), a sub-mode (2 bytes), and a data type (2 bytes).

b2. Writing of audio data

0028Four modes are determined when audio data in CD-I is written.

0029One of the modes is based on the same recording system as that of the existing CD-DA in which the sampling frequency is set to 44.1 kHz and the number of quantization bits is set to 16 bits. This mode intends to perform a super Hi-Fi reproduction.

0030In another mode, an ADPCM (Adaptive Differential PCM) is used as a recording method. The sampling frequency is set to 37.8 kHz and the number of quantization bits is set to 8 bits. In this mode, a sound quality which is close to that of an LP record can be reproduced. The reproducing time is set to two hours in the stereophonic mode and is set to four hours in the monaural mode. This mode intends to perform a Hi-Fi reproduction.

0031In still another mode, the ADPCM is used as a recording method. The sampling frequency is set to 37.8 kHz and the number of quantization bits is set to 4 bits. In this mode, a sound quality which is close to that of an FM broadcasting can be reproduced. The reproducing time is set to four hours in the stereophonic mode and is set to eight hours in the monaural mode. This mode intends to perform a Hi-Fi reproduction of a long time.

0032In further another mode, the ADPCM is used as a recording method. The sampling frequency is set to 18.9 kHz and the number of quantization bits is set to 4 bits. The reproducing time is set to eight hours in the stereophonic mode and set to sixteen hours in the monaural mode. This mode intends to perform a speech reproduction.

b3. Writing of video data

0033Image data is processed as follows in accordance with the type of image data.

0034In the case of a natural image, the sampling frequency of a luminance signal Y is set to 7.6 MHz and the sampling frequencies of color difference signals U and V are set to 3.8 MHz. The image data is sampled at ratios of 4 : 2 : 2. Bits are compressed to four bits and recorded. They are returned to eight bits upon reproduction.

0035In the case of graphics, a CLUT (Color Lookup Table) is used. The CLUT graphics include three modes of 256 colors (8 bits), 128 colors (7 bits), and 16 colors (4 bits). Necessary colors can be selected from sixteen million colors and used.

0036In the case of an animation, a run length code is used. In this case, image data is compressed by using color information and a length between pixels. An animation on a full screen can be realized by using such a code.

b4. Disc

0037In the CD-I disc, mechanical dimensions such as outer diameter dimension, center hole dimension, thickness, and the like, optical parameters such as refractive index, reflectance, and the like, recording parameters such as disc rotating direction, recording linear velocity, track shape, track pitch, and the like, use environment situations, and the like are all similarly set those of an ordinary compact disc (CD-DA) for a music.

0038The disc is constructed in a manner such that it is possible to discriminate whether the disc is a CD-I disc or not on the basis of the contents in a TOC (Table of Contents) of a lead-in area of the disc. That is, in the CD-I disc or CD-I/CD-DA disc, a PSEC is set to 10 when (POINT = A0). On the other hand, in the other discs, the PSEC when (POINT = A0) is set to a value other than 10. For example, in the CD-DA disc, the PSEC when (POINT = A0) is set to 00. Therefore, from the PSEC when (POINT = A0), it is possible to judge whether the disc is a CD-I disc or a CD-I/CD-DA disc or another disc. Control fields of (POINT = A0, A1, A2) of the CD-I disc are set to (01 x 0). A control field of (POINT = A0) of the CD-I/CD-DA disc is always set to (01 x 0) and the other control fields are set to (00 x 0). Consequently, from the control field, it is possible to judge whether the disc is a CD-I disc or a CD-I/CD-DA disc.

b5. Hardware

0039In the CD-I, since audio data is included and a high-speed process in a real-time manner is needed, a process by a machine language is executed. As a CPU for such a purpose, a CPU of 16 bits of the 68000 type which has been developed by Motorola Inc. is designated. A CD-RTOS (Real-Time Operating System) which handles various kinds of files fundamentally uses the OS9 and the program is assembled as an ROM into the system. At least an X-Y device and two trigger buttons are prepared as an input device. Two systems of audio and video are prepared as an output. The CD-I player can reproduce a CD-DA for musics.

c. Internal construction of an embodiment

0040Fig. 4 shows an internal construction of the CD-I player 1 to which the invention has been applied.

0041In Fig. 4, a disc 15 is rotated by a spindle motor 21 at a CLV (constant linear velocity). The rotation of the spindle motor 21 is controlled by a spindle servo circuit 22 on the basis of clocks which are reproduced by a CD reproducing circuit 28. An output of a system controller 20 is supplied to the spindle servo circuit 22.

0042A recording signal on the disc 15 is reproduced by an optical head 23. The optical head 23 is supported by a biaxial device. An output of a focusing/tracking servo circuit 25 is supplied to the biaxial device. The output of the system controller 20 is supplied to the focusing/tracking servo circuit 25. The focusing/tracking servo circuit 25 applies servo controls to two axes for the optical head 23 in the focusing direction and the tracking direction on the basis of an output of a photo detector.

0043The optical head 23 is made movable in the radial direction of the disc 15 by a slide feeding mechanism 24 using, for instance, a linear motor. The slide feeding mechanism 24 is controlled by a threading servo circuit 26. The output of the system controller 20 is supplied to the threading servo circuit 26. The optical head 23 can be accessed to a desired track position by the slide feeding mechanism 24.

0044An output of the optical head 23 is supplied to a CD reproducing circuit 28 through an RF amplifier 27. The CD reproducing circuit 28 comprises a reproducing circuit of bit clocks, an EFM demodulating circuit, a CIRC error correction circuit, and the like. The CD reproducing circuit 28 EFM demodulates the output of the optical head 23 and executes an error correcting process. The CD reproducing circuit 28 is controlled by the system controller 20.

0045An output of the CD reproducing circuit 28 is supplied to a CD-ROM reproducing circuit 29. The CD-ROM reproducing circuit 29 comprises a sync detecting circuit, a descrambling circuit, an error correction circuit, and the like. A sync signal is detected by the CD-ROM reproducing circuit 29 and the scramble is released. A header address is checked and a target block is accessed. In the case of the form 1, the error correcting process is further executed. The CD-ROM reproducing circuit 29 is controlled by the system controller 29.

0046An input from an input device 30 is given to the system controller 20. The input device 30 comprises the X-Y device 11 and two trigger buttons 10A and 10B.

0047Reference numeral 31 denotes a CPU to control the CD-I system. A CPU of the 68000 type is used as a CPU 31. A master controller 32 is connected to the CPU 31. The CPU 31 and the system controller 20 are bidirectionally connected. A bus 33 is led out of the CPU 31. One chip in which the CPU 31 and the master controller 32 are assembled can be also used.

0048The data reproduced by the CD-ROM reproducing circuit 29 is sent to the bus 33. RAMs 35A and 35B are connected to the bus 33 through video controllers 34A and 34B, respectively. A system ROM 36 and a non-volatile RAM 37 which is backed up by batteries are bidirectionally connected to the bus 33. An audio decoder 38 is connected to the bus 33.

0049The image data in the data reproduced by the CD-ROM reproducing circuit 29 is supplied to video controllers 34A and 34B under control of the CPU 31. Video signals based on the image data are formed by the video controllers 34A and 34B. The video signals are supplied to a video synthesizer 39. The video synthesizer 39 synthesizes the video signal from the video controller 34A and the video signal from the video controller 34B. An output of the video synthesizer 39 is supplied to the LCD display 13 via an LCD driving circuit 40. The driving of the LCD display 13 can be turned on/off by the LCD driving switch 14.

0050The audio data in the data reproduced by the CD-ROM reproducing circuit 29 is supplied to the audio decoder 38 under control of the CPU 31. In the case of the audio data based on the ADPCM, the audio decoder 38 ADPCM decodes the audio data. The decoded audio data is supplied to the D/A converter 41 and is converted into the analog signal. The analog signal is generated from the head phones output terminal 3 through a low pass filter 42 and an amplifier 43. An audio signal level which is generated from the head phones output terminal 3 can be set by the sound volume adjusting dial 4.

d. Operation of an embodiment

0052The operation of an embodiment of the invention will now be described. Fig. 5 shows the operation when the LCD display 13 is turned on.

0053In Fig. 5, when the power source is turned on by the power on/off switch 5 (Fig. 1), a check is made to see if a calendar and an internal clock have been set or not (step 51).

0054In the case of setting the calendar and the internal clock, the calendar and the internal clock are set by using the X-Y device 11 and the trigger buttons 10A and 10B (step 52). After the calendar and the internal clock were set, a check is made to see if the disc has been loaded or not (step 53).

0055If the calendar and the internal clock are not set in step 51, step 53 follows and a check is made to see if the disc has been loaded or not.

0056If the disc is not loaded, an indication of the unloaded state of the disc is displayed by the LCD display 13 (step 54). That is, if the disc is not loaded, as shown in Fig. 6A, an indication of the unloaded state of the disc is displayed in a display area 45 of the LCD display 13 and the calendar and the time are displayed in a display area 46.

0057The discrimination regarding the loading of the disc is continued (step 55).

0058If it is detected in step 53 or step 55 that the disc has been loaded, the TOC of the innermost rim of the disc is accessed (step 56).

0059From the data of the TOC, a check is first made to see if the loaded disc is a CD-I/CD-DA disc or a CD-I disc or a CD-DA disc (step 57). That is, in the case of the CD-I disc or CD-I/CD-DA disc, PSEC when (POINT = A0) is set to 10. In the case of another disc, since PSEC when (POINT = A0) has been set to 00, a check is made from the PSEC when (POINT = A0) to see if the disc is a CD-I disc or a CD-DA disc.

0060If it is decided that the disc is the CD-DA disc, an indication when the CD-DA disc has been loaded is displayed in the LCD display 13 (step 58). That is when the CD-DA disc has been loaded, as shown in Fig. 6B, a content indicating that the disc has been loaded is displayed in the display area 45 of the LCD display 13. An indication of an operation key such as PLAY, AMS, STOP, etc. to operate the CD-DA is displayed in the display area 46.

0061When the operation key displayed in the display area 46 is operated by using the X-Y device 11 and the trigger buttons 10A and 10B, the CD-DA disc is reproduced in accordance with the above operation (step 59).

0062If it is determined in step 57 that the disc is not the CD-DA disc, a check is made to see if the disc is a CD-I disc or a CD-I/CD-DA disc (step 60). Namely, control fields of (POINT = A0, A1, A2) of the CD-I disc are set to (01 x 0) and a control field of (POINT = A0) of the CD-I/CD-DA disc is always set to (01 x 0). The other control fields are set to (00 x 0). Therefore, from the control field, it is judged whether the disc is the CD-I disc or the CD-I/CD-DA disc.

0063If it is determined that the loaded disc is the CD-I disc, an indication when the CD-I disc has been loaded is displayed on the LCD display 13 (step 61). That is, if the CD-I disc has been loaded, as shown in Fig. 6C, an indication showing that the disc has been loaded is displayed in the display area 45 of the LCD display 13. A title and the like of an application software are displayed in the display area 47.

0064When operating by using the X-Y device 11 and the trigger buttons 10A and 10B in accordance with an instruction of the application software, the CD-I disc is reproduced in accordance with the operation (step 62).

0065If it is decided that the loaded disc is the CD-I/CD-DA disc, an indication when the CD-I/CD-DA disc has been loaded is displayed on the LCD display 13 (step 64). That is, when the CD-I/CD-DA disc has been loaded, as shown in Fig. 6D, an indication showing that the disc has been loaded is displayed in the display area 45 of the LCD display 13. An indication of the operation key such as PLAY, AMS, STOP, or the like to operate the CD-DA is displayed in the display area 46. The title and the like of the application software are displayed in a display area 47.

0066In the case of the CD-I/CD-DA disc, a check is made to see if only the CD-DA is reproduced or not (step 65). When the operation key displayed in the display area 46 is operated by using the X-Y device 11 and the trigger buttons 10A and 10B, only the portion of the CD-DA area is reproduced in accordance with the operation (step 66). When operating by using the X-Y device 11 and the trigger buttons 10A and 10B in accordance with the instruction of the application software, the CD-I/CD-DA is reproduced in accordance with the operation (step 67).

0067As mentioned above, according to an embodiment of the invention, in the case of the CD-I/CD-DA disc, only the CD-DA area can be reproduced. Thus, only the sounds of the application software can be enjoyed.

e. Operation when display is unnecessary

0068In the case of reproducing the CD-DA disc, only the audio data is reproduced, so that there is no need to display on the LCD display 13. In the case of reproducing only the audio data from the CD-I/CD-DA disc as well, there is no need to display on the LCD display 13. As mentioned above, if the LCD display 13 driven when the screen display is unnecessary, an electric power is vainly consumed. In the embodiment of the invention, therefore, when there is no need to display a screen, by enabling the LCD display 13 to be turned off by the LCD driving switch 14, the electric power consumption can be reduced.

0069If the LCD display 13 is turned off, however, it is impossible to execute the operation while looking at the indication on the LCD display 13. It is also possible to provide special keys for audio reproduction in addition to the X-Y device 11 and the trigger buttons 10A and 10B. However, if such keys are provided, the number of keys increases and the apparatus enlarges in size. In the embodiment of the invention, accordingly, the X-Y device 11 and the trigger buttons 10A and 10B are allowed to function as special keys for audio reproduction when the loaded disc is the CD-DA disc and the driving of the LCD display 13 has been turned off or when the loaded disc is the CD-DA disc and only the audio reproduction is executed and the driving of the LCD display 13 has been turned off. That is, for instance, the left direction and the right direction of the X-Y device 11 function as an "AMS key", the trigger button 10A functions as a "PLAY/PAUSE key", and the trigger button 10B functions as a "STOP key". Consequently, even when the driving of the LCD display 13 has been stopped, various audio reproducing operations can be freely executed.

0070Since the video reproduction is not performed in the CD-DA disc, it is also possible to construct in a manner such that if the CD-DA disc has been loaded, the X-Y device 11 and the trigger buttons 10A and 10B can be allowed to function as special keys for audio reproduction irrespective of the on/off of the LCD display 13. It is also possible to construct in a manner such that the X-Y device 11 and the trigger buttons 10A and 10B are allowed to function as special keys for audio reproduction irrespective of the kind of disc if the LCD display 13 has been turned off.

f. Operations which are executed by displaying keys onto the screen

0071In the CD-I, all of the operations can be executed by the two trigger buttons 10A and 10B and the X-Y device 11. However, there is a case where adequate operations cannot be performed by such two trigger buttons 10A and 10B and X-Y device 11. Accordingly, in the embodiment of the invention, operation keys are displayed in the application picture plane and various operations can be executed.

0072That is, as shown in Fig. 7A, when the trigger button 10A or 10B is pressed in a state in which the application picture plane is displayed, an operation key 71 is displayed in the picture plane as shown in Fig. 7B. The operation key 71 is similar to an operation key such as PLAY, STOP, AMS, etc. which is provided for the compact disc for musics. By constructing the operation key 71 in a manner similar to the operation keys provided for the compact disc for musics as mentioned above, the operations according to those of the compact disc for musics can be executed and the operability is improved. A key arrangement, a shape of key, and a function of the key can be arbitrarily set in consideration of the operability. By operating the operation key 71 displayed by using the X-Y device 11 and the trigger buttons 10A and 10B, various kinds of operations can be performed.

0073According to the invention, when the trigger button 10A or 10B is pressed in a state in which the application picture plane is displayed, the operation key 71 is displayed in the picture plane. Various operations can be performed by operating the operation key 71 displayed by using the X-Y device 11 and the trigger buttons 10A and 10B. As mentioned above, by displaying the operation key 71 on the screen and by operating the operation key 71 by using the X-Y device 11 and the trigger buttons 10A and 10B, various kinds of operations can be executed by the limited number of X-Y device 11 and trigger buttons 10A and 10B and the operability is improved. By constructing the operation key 71 which is displayed in a manner similar to the operation keys provided for the compact disc for musics, operations similar to those of the compact disc for musics can be executed and the operability is improved.