Patent Application
20110074919
1. Field of the Invention
In general, the present invention relates to a signal generation apparatus and shutter spectacles for the apparatus. More particularly, the present invention relates to a timing-signal generation apparatus making a display apparatus capable of displaying a 3-d (three-dimensional) stereoscopic video image content to the user even if the display apparatus for displaying the video image content does not have a function to output a timing signal and relates to shutter spectacles for the timing-signal generation apparatus.
2. Description of the Related Art
In recent years, the popularization of a TV receiver having a flat panel display screen has been making progress at a high pace. Typical examples of the flat panel display screen are an LCD (Liquid Crystal Display) screen and a PDP (Plasma Display Panel) screen. In addition, in December 2003, terrestrial digital broadcasting has been started so that video images of high-quality and high-definition broadcasting can be watched also at homes. On top of that, recently, the popularization of the recording/reproduction apparatus for high-vision video images has also been making progress at a high pace so that there is now already provided an environment that allows the user to watch not only video images of high-vision broadcasting but also contents recorded on a package medium as contents each having a high-vision image quality. In such a condition, flat panel display screens are announced one after another as screens which are each capable of displaying 3-d stereoscopic video image contents.
As a method for watching a 3-d stereoscopic video image, there are two large categories, that is, a spectacle method and a naked-eye method. The spectacle method is a method making use of polarization-filter spectacles or shutter spectacles. On the other hand, the naked-eye method is a method not making use of spectacles. Typical examples of the naked-eye method are a lenticular method and a parallax barrier method. For more information on the methods for watching 3-d stereoscopic video images, the reader is advised to refer to documents such as Japanese Patent Laid-Open No. 2006-126501. From the view of compatibility with a 2-d (two-dimensional) video image display screen, rather than the naked-eye method, the spectacle method is expected to become the popular video image watching method adopted in general homes in the near future.
As shown in the figure, a display screen 1 alternately shows video images for the left eyes and video images for the right eyes. The video images for the left eyes and video images for the right eyes consecutively appear on the display screen 1 as video images arranged along the time axis. To put it more concretely, the display screen 1 shows a left-eye video image L1, a right-eye video image R1, a left-eye video image L2, a right-eye video image R2, a left-eye video image L3, a right-eye video image R3 and so on.
The user watching the 3-d stereoscopic video images wears shutter spectacles 2. The shutter spectacles 2 receive a timing signal for determining timings to open and close two shutters which are employed in the shutter spectacles 2 to serve as respectively a shutter for the left eye and a shutter for the right eye. Each of the shutters employed in the shutter spectacles 2 is a liquid crystal device. The liquid-crystal device for the left eye has a polarization characteristic which is different from the polarization characteristic of the liquid-crystal device for the right eye. The shutter spectacles 2 carry out two different shutter opening and closing operations. To be more specific, the shutter spectacles 2 alternately and repeatedly carry out an operation to open the shutter for the left eye while closing the shutter for the right eye and an operation to close the shutter for the left eye while opening the shutter for the right eye in synchronization with the timing signal. As a result, only the video images for the left eye are supplied to the left eye of the user and only the video images for the right eye are supplied to the right eye of the user.
A disparity between every video image for the left eye and every counterpart video image for the right eye has been provided for the video image for the left eye and the counterpart video image for the right eye. Even though every video image for the left eye and every video image for the right eye are each a 2-d video image, the disparity between every video image for the left eye and the associated video image for the right eye allows the user to sense the video images for the left eye and the video images for the right eye as a 3-d stereoscopic video image.
As described above, in order to watch a 3-d stereoscopic video image by adoption of the spectacle method, it is necessary to provide shutter spectacles capable of receiving a timing signal which is synchronized with the 2-d video images representing the 3-d stereoscopic video image.
However, watching of 3-d stereoscopic video image contents cannot be said to have been popularized widely yet. In the present state of the art, an apparatus for displaying video images generally does not have a function to output a timing signal. A typical example of the apparatus for displaying video images is the TV receiver.
Addressing the problem described above, inventors of the present invention have proposed a signal generation apparatus making a display apparatus capable of displaying a 3-d stereoscopic video image content to the user even if the display apparatus for displaying the video image content does not have a function to output a timing signal.
A signal generation apparatus according to a first embodiment of the present invention includes:
bit-clock extraction means for receiving a digital audio signal output by an apparatus for displaying a two-dimensional video image used for sensing a three-dimensional stereoscopic video image on a screen determined in advance and for extracting a bit clock signal from the digital audio signal; and
timing-signal generation means for generating a timing signal having the same period as a vertical synchronization signal of the two-dimensional video image from the bit clock signal extracted by the bit-clock extraction means.
In accordance with the first embodiment of the present invention:
the bit-clock extraction means receives a digital audio signal output by an apparatus for displaying a 2-d video image used for sensing a 3-d stereoscopic video image on a screen determined in advance and extracts a bit clock signal from the digital audio signal; and
the timing-signal generation means generates a timing signal having the same period as a vertical synchronization signal of the 2-d video image from the bit clock signal extracted by the bit-clock extraction means.
Shutter spectacles according to a second embodiment of the present invention includes:
bit-clock extraction means for receiving a digital audio signal output by an apparatus for displaying a two-dimensional video image used for sensing a three-dimensional stereoscopic video image on a screen determined in advance and for extracting a bit clock signal from the digital audio signal;
timing-signal generation means for generating a timing signal having the same period as a vertical synchronization signal of the two-dimensional video image from the bit clock signal extracted by the bit-clock extraction means; and
shutter driving means for driving a shutter for a left eye and a shutter for a right eye on the basis of the timing signal generated by the timing-signal generation means.
In accordance with the second embodiment of the present invention:
the bit-clock extraction means receives a digital audio signal output by an apparatus for displaying a 2-d video image used for sensing a 3-d stereoscopic video image on a screen determined in advance and extracts a bit clock signal from the digital audio signal;
the timing-signal generation means generates a timing signal having the same period as a vertical synchronization signal of the 2-d video image from the bit clock signal extracted by the bit-clock extraction means; and
the shutter driving means drives a shutter for the left eye and a shutter for the right eye on the basis of the timing signal generated by the timing-signal generation means.
In accordance with the first and second embodiments of the present invention, it is possible to display a 3-d stereoscopic video image content even if an apparatus for displaying the video image content does not have a function to output a timing signal.
Preferred embodiments of the present invention are explained in chapters which are arranged in an order shown below. In the following description, each of the preferred embodiments is referred to merely as an embodiment.
This chapter explains the configuration of a timing-signal generation apparatus 22 for generating a timing signal to be supplied to shutter spectacles 23 external to the timing-signal generation apparatus 22.
This chapter explains the configuration of intelligent shutter spectacles 61 employing the timing-signal generation apparatus for generating a timing signal to be supplied to a shutter driving section 71 also employed in the intelligent shutter spectacles 61.
This chapter explains the configuration of a 3-d stereoscopic video image watching system including a wireless head phone.
This chapter explains the configuration of a 3-d stereoscopic video image watching system including a reproduction apparatus.
The 3-d stereoscopic video image watching system 11 shown in the diagram of
The TV receiver 21 is configured to include a flat-panel display screen such as an LCD screen or a PDP display screen. The TV receiver 21 displays 2-d video images based on 3-d stereoscopic data to serve as video images used for allowing the user to sense a 3-d stereoscopic video image obtained as a result of watching the 2-d video images. The TV receiver 21 is capable of receiving the 3-d stereoscopic video image data as a broadcast signal.
As explained earlier by referring to the diagram of
In this specification, a 2-d video image is a 2-d video image used for allowing the user to sense a 3-d stereoscopic video image obtained as a result of watching a plurality of such 2-d video images.
It is to be noted that the format of the 3-d stereoscopic video image data received by the TV receiver 21 is not prescribed in particular. A typical example of the format of the 3-d stereoscopic video image data received by the TV receiver 21 is a format of including a video image for the left eye and the right-eye video image associated with the video image for the left eye as a set. Another typical example of the format of the 3-d stereoscopic video image data received by the TV receiver 21 is a format of including a 2-d video image and the information on the depths of the 2-d video image as a set.
The TV receiver 21 does not have an output terminal for outputting a timing signal demanded by the shutter spectacles 23 worn by the user who is watching 3-d stereoscopic video images by adoption of the spectacle method. However, the TV receiver 21 is provided with a digital audio output terminal 21a for outputting a digital audio signal conforming to the IEC (International Electrotechnical Commission) 60958 standard which is also referred to as the S/PDIF (Sony Philips Digital Inter Face) standard. There are some types of the digital audio output terminal 21a which conforms to the IEC60958 standard. The types of the digital audio output terminal 21a conforming to the IEC60958 standard include an optical digital audio output terminal and a coaxial digital audio output terminal.
The timing-signal generation apparatus 22 is connected to the digital audio output terminal 21a of the TV receiver 21 by a cable 31. If the digital audio output terminal 21a of the TV receiver 21 is an optical digital audio output terminal, an optical cable is used as the cable 31. If the digital audio output terminal 21a of the TV receiver 21 is a coaxial digital audio output terminal, on the other hand, a coaxial cable is used as the cable 31. It is to be noted that many contemporary video-image display apparatus have an optical digital audio output terminal.
The timing-signal generation apparatus 22 receives an audio signal from the TV receiver 21 which transmits the signal to the timing-signal generation apparatus 22 through the cable 31. The timing-signal generation apparatus 22 generates a timing signal from the audio signal received from the TV receiver 21. The timing signal is a signal synchronized to 2-d video images which are displayed on the TV receiver 21. Then, the timing-signal generation apparatus 22 transmits the timing signal generated thereby to the shutter spectacles 23 by radio communication such as the infrared communication or the RF (radio frequency) communication.
It is to be noted that the timing-signal generation apparatus 22 has an operation button 32. Functions of the operation button 32 will be described later.
The shutter spectacles 23 have the function of a signal receiving apparatus. That is to say, the shutter spectacles 23 are capable of receiving the timing signal from the timing-signal generation apparatus 22 which transmits the timing signal by the radio communication. Much like the shutter spectacles 2 shown in the diagram of
Even though every video image for the left eye and every video image for the right eye are each a 2-d video image, the disparity between every video image for the left eye and the associated video image for the right eye allows the user wearing the shutter spectacles 23 to sense the video images for the left eye and the video images for the right eye as a 3-d stereoscopic video image.
As shown in the block diagram, the configuration of the timing-signal generation apparatus 22 includes an operation button 32, an audio-signal IF section 41, a bit clock frequency determination section 42, a timing-signal generation section 43, a phase adjustment section 44, a timing-signal outputting section 45 and an oscillation section 46.
The audio-signal IF section 41 is a section for receiving an audio signal from the TV receiver 21 which transmits the audio signal to the timing-signal generation apparatus 22 through the cable 31. In addition, the audio-signal IF section 41 also extracts a clock signal from the audio signal received from the TV receiver 21. The audio-signal IF section 41 then supplies the clock signal extracted from the audio signal IF section 41 to the bit clock frequency determination section 42. It is to be noted that a signal receiving interface device generally put in the market as a signal receiving interface device conforming to the IEC60958 standard can be used to serve as the audio-signal IF section 41. In the following description, the clock signal extracted by the audio-signal IF section 41 from the audio signal is particularly referred to as a bit clock signal whereas the frequency of the bit clock signal is also referred to as a bit clock frequency.
The bit clock frequency determination section 42 measures the frequency of the bit clock signal received from the audio-signal IF section 41 on the basis of a reference clock signal generated by the oscillation section 46. Then, by referring to a table shown in the diagram of
The timing-signal generation section 43 is a section for generating a timing signal by making use of pieces of information which have been received by the timing-signal generation section 43 from the bit clock frequency determination section 42 as information on the identified sampling frequency of the audio signal and information on the frequency of the bit clock signal. The timing signal generated by the timing-signal generation section 43 is a signal having the same period as a vertical synchronization signal which is used in an operation to display a 2-d video image. Details of the processing carried out by the timing-signal generation section 43 will be described later by referring to tables shown in
The timing-signal generation section 43 supplies the timing signal generated thereby to the phase adjustment section 44. The timing signal generated by the timing-signal generation section 43 has a frequency matching the frequency of the vertical synchronization signal, but there is no assurance that the phase of the timing signal matches the phase of the vertical synchronization signal. However, the user is allowed to operate the operation button 32 in order to adjust the phase of the timing signal generated by the timing-signal generation section 43 to the phase of the vertical synchronization signal.
That is to say, if the phase of the timing signal does not match the phase of the vertical synchronization signal, the user cannot sense 2-d video images displayed on the TV receiver 21 as a 3-d stereoscopic video image. However, the user can keep operating the operation button 32 by pressing the operation button 32 till the user senses 2-d video images displayed on the TV receiver 21 as a 3-d stereoscopic video image. When the user presses the operation button 32, a signal generated by the operation button 32 is supplied to the phase adjustment section 44. While the user is pressing the operation button 32, the signal generated by the operation button 32 is driving the phase adjustment section 44 to carry out processing to shift the phase of the timing signal received by the phase adjustment section 44 from the timing-signal generation section 43.
In addition, it is even more desirable to display the so-called determination video image on the TV receiver 21 at the phase adjustment time. The determination video image is an image used for easily determining whether or not the 3-d stereoscopic video image watching system 11 has been put in a state in which the user can sense 2-d video images displayed on the TV receiver 21 as a 3-d stereoscopic video image. A typical example of the determination video image used for easily determining whether or not the 3-d stereoscopic video image watching system 11 has been put in the state is an image which is seen as a simple video image such as a stick when the 3-d stereoscopic video image watching system 11 has been put in such a state.
After the phase adjustment section 44 has adjusted the phase of the timing signal, the phase adjustment section 44 supplies the timing signal having the adjusted phase to the timing-signal outputting section 45. With the operation button 32 not pressed by the user, on the other hand, the phase adjustment section 44 passes on the timing signal received from the timing-signal generation section 43 to the timing-signal outputting section 45 with the phase of the timing signal kept as it is.
The timing-signal outputting section 45 converts the timing signal received from the phase adjustment section 44 into an output signal such as an infrared signal or an RF (radio frequency) signal and transmits the output signal to the shutter spectacles 23. Thus, the timing-signal outputting section 45 can thus be designed as an infrared communication module or an RF communication module.
The oscillation section 46 is typically a liquid-crystal oscillator for generating the reference clock signal cited above. The oscillation section 46 supplies the reference clock signal to the bit clock frequency determination section 42, the timing-signal generation section 43 and the phase adjustment section 44. In the first embodiment, the oscillation section 46 generates the reference clock signal having a frequency of 1 MHz.
As described above, the timing-signal generation apparatus 22 is configured to generate a timing signal by making use of a digital audio signal received from the digital audio output terminal 21a of the TV receiver 21 and transmit the timing signal to the shutter spectacles 23.
Next, processing carried out by the sections composing the timing-signal generation apparatus 22 are explained in detail by referring to diagrams of
Let the TV receiver 21 display a pair of 2-d video images, that is, a 2-d video image for the left eye and a 2-d video image for the right eye, in a time period T [msec]. In this case, a time period demanded for displaying a 2-d video image for the left eye or a 2-d video image for the right eye has a length of T/2 [msec]. The timing signal demanded in the operation to display such 2-d video images is the timing signal shown in the diagram of
As shown in the figure, the audio signal conforming to the IEC60958 standard is a serial digital signal. The audio signal conforming to the IEC60958 standard is a signal obtained as a result of an encoding process adopting an encoding method which is referred to as a bi-phase encoding method.
In the encoding process adopting the bi-phase encoding method, a signal used as an input to the encoding process is encoded in accordance with the following rules. If the signal used as an input to the encoding process represents data of 1, the period of the signal obtained as a result of the encoding process is converted into a period having a length equal to two times the length of the period of the signal used as an input to the encoding process. If the signal used as an input to the encoding process represents data of 0, on the other hand, the period of the signal used as an input to the encoding process is used as it is as the period of the signal resulting from the encoding process. In the following description, the signal used as an input to the encoding process is also referred to as an input signal whereas the signal obtained as a result of the encoding process is also referred to as an output signal.
In addition, in the encoding process adopting the bi-phase encoding method, during every period representing 1 bit, the signal is always inverted.
Since the audio signal obtained as a result of the encoding process is always inverted during every period representing 1 bit, a bit clock signal serving as a clock signal corresponding to 1 bit can be extracted from the audio signal even if a clock signal itself is not transmitted.
An audio signal conforming to the IEC60958 standard is transmitted in units which are each referred to as a sub-frame.
As shown in the figure, a sub-frame is used to accommodate an audio sample for the L (left) or R (right) channel. The audio sample is data representing the amplitude of a sound. Two sub-frames form a unit referred to as a frame. The two sub-frames forming a frame are a sub-frame of the L channel and a sub-frame of the R channel. 192 consecutive frames further form a unit referred to as a block.
A sub-frame is configured to have a length of 32 bits.
4 bits at the left end of the figure are 4 most significant bits of the sub-frame. These 4 most significant bits of the sub-frame form a bit pattern for detecting synchronization. These 4 most significant bits of the sub-frame are referred to as a sync code or a pre-amble code.
The 5th bit (bit 4) to the 28th bit (bit 27) from the most significant bit (bit 0) of the sub-frame are used to accommodate the audio sample which is data representing the amplitude of a sound as described above.
The 29th bit (bit 28) from the most significant bit of the sub-frame is a V (validity) bit referred to as a validity flag. The validity flag is a flag used for indicating whether the sub-frame is valid or not. The 30th bit (bit 29) following the V bit is a U bit referred to as a user data bit. The 31st bit (bit 30) following the U bit is a C bit referred to as a channel status bit. The 32nd bit (bit 31) following the C bit is a P bit referred to as a parity bit.
The bit clock frequency determination section 42 is a section for measuring the frequency of the bit clock signal received from the audio-signal IF section 41 on the basis of the reference clock signal received from the oscillation section 46.
The following description explains processing carried out by the bit clock frequency determination section 42 to measuring the frequency of the bit clock signal received from the audio-signal IF section 41 on the basis of the reference clock signal received from the oscillation section 46. As a typical case, let the sampling frequency of the audio signal received from the TV receiver 21 be 48 kHz.
At a sampling frequency of 48 kHz, let the audio signal received from the TV receiver 21 be a stereo audio signal for the L (left) and R (right) channels. In this case, the stereo audio signal having a sampling frequency of 48 kHz is transmitted in sub-frame units which each have a length of 32 bits. Thus, the frequency of the bit clock signal received from the audio-signal IF section 41 satisfies the following equation:
Frequency=48 [kHz]×2 [ch]×32 [bits]=3.072 [MHz]
That is to say, the bit clock frequency in this case is found to be 3.072 MHz.
For sampling frequencies of 32 kHz, 44.1 kHz, 96 kHz and 192 kHz, the bit clock frequency can be computed in the same way as the sampling frequency of 48 kHz.
As described above, the bit clock frequency determination section 42 measures the bit clock frequency of the bit clock signal received from the audio-signal IF section 41 on the basis of the reference clock signal received from the oscillation section 46. Then, by making use of the equation described above, the bit clock frequency determination section 42 recognizes a sampling frequency of the audio signal received from the TV receiver 21 from the bit clock frequency which results from the measurement as the frequency of the bit clock signal. However, even though the frequency of the reference clock signal received from the oscillation section 46 is 1 MHz, the bit clock frequency being measured is at least 2.048 MHz which is higher than the frequency of the reference clock signal. That is to say, the bit clock period being measured is too short to be measured in terms of reference clock periods. In order to solve this problem, the bit clock frequency determination section 42 divides the bit clock frequency and measures the bit clock period of a bit clock signal obtained as a result of the frequency division in order to find the bit clock frequency of the post-frequency-division bit clock signal.
In the first embodiment, the bit clock frequency determination section 42 divides the bit clock frequency by 1,000 and measures the period of a bit clock signal obtained as a result of the frequency division by making use of the reference clock signal. That is to say, the bit clock frequency determination section 42 measures the period of a bit clock signal obtained as a result of the frequency division in terms of reference clock periods. The reference clock period is the period of the reference clock signal generated by the oscillation section 46.
The period of the reference clock signal generated by the oscillation section 46 is 1/1 MHz=1 microsecond. Thus, the bit clock period obtained as a result of dividing the bit clock frequency by 1,000 can be measured in terms of reference clock periods. If the bit clock period obtained as a result of dividing the bit clock frequency by 1,000 is found to be 325 reference clock periods or 325 microseconds for example, the bit clock frequency determination section 42 determines that the bit clock frequency is 3.072 MHz.
Next, processing carried out by the timing-signal generation section 43 is explained as follows.
The timing-signal generation section 43 is a section for generating a timing signal by making use of pieces of information which have been received by the timing-signal generation section 43 from the bit clock frequency determination section 42 as information on the identified sampling frequency of the audio signal and information on the frequency of the bit clock signal. The timing signal generated by the timing-signal generation section 43 is a signal having the same period as a vertical synchronization signal which is used in an operation to display a 2-d video image.
To be more specific,
On the other hand,
The timing-signal generation apparatus 22 determines in advance whether the frequency of the timing signal to be generated by the timing-signal generation section 43 is 60 Hz or 59.94 Hz. As is obvious from the above description, the frequency of the timing signal to be generated by the timing-signal generation section 43 is the frequency of a vertical synchronization signal which is used in an operation to display a 2-d video image on the TV receiver 21.
The timing-signal generation section 43 receives the bit clock frequency and the bit clock signal from the bit clock frequency determination section 42. Let the timing-signal frequency determined in advance by the timing-signal generation section 43 be 60 Hz. In this case, if the bit clock frequency is 3.072 MHz, the timing-signal generation section 43 selects the frequency division rate of 1/51200 for the bit clock frequency of 3.072 MHz. Then, the timing-signal generation section 43 divides the bit clock frequency of 3.072 MHz by 51,200 in order to result in a timing-signal frequency of 60 Hz which is equal to the frequency of a vertical synchronization signal used in an operation to display a 2-d video image on the TV receiver 21. For any other bit clock frequency, the timing-signal generation section 43 selects a frequency division rate for the other bit clock frequency and computes the frequency of a timing signal being generated in the same way as the bit clock frequency of 3.072 MHz.
As another example, let the timing-signal frequency determined in advance by the timing-signal generation section 43 be 59.94 Hz. In this case, if the bit clock frequency is 6.144 MHz, the timing-signal generation section 43 selects the frequency division rate of 5/512512 for the bit clock frequency of 6.144 MHz. Then, the timing-signal generation section 43 multiplies the bit clock frequency of 6.144 MHz by the frequency division rate of 5/512512 in order to result in a timing-signal frequency of 59.94 Hz which is equal to the frequency of a vertical synchronization signal used in an operation to display a 2-d video image on the TV receiver 21. For any other bit clock frequency, the timing-signal generation section 43 selects a frequency division rate for the other bit clock frequency and computes the frequency of a timing signal being generated in the same way as the bit clock frequency of 6.144 MHz.
As shown in the figure, the flowchart begins with a step S1 at which the audio-signal IF section 41 employed in the timing-signal generation apparatus 22 receives an audio signal from the TV receiver 21 which transmits the audio signal to the audio-signal IF section 41 through the cable 31.
Then, at the next step S2, the audio-signal IF section 41 extracts a bit clock signal from the audio signal received from the TV receiver 21 and supplies the bit clock signal to the bit clock frequency determination section 42.
Subsequently, at the next step S3, the bit clock frequency determination section 42 measures the bit clock frequency which is the frequency of the bit clock signal received from the audio-signal IF section 41. To put it more concretely, the bit clock frequency determination section 42 divides the frequency of the bit clock signal by 1,000 and measures the period of a bit clock signal obtained as a result of the frequency division in terms of reference clock periods. The reference clock period is the period of the reference clock signal received from the oscillation section 46. Then, the bit clock frequency determination section 42 collates the period of a bit clock signal obtained as a result of the frequency division with periods shown on the rightmost column of the table shown in
Then, at the next step S4, the timing-signal generation section 43 selects a frequency division rate from a frequency division rate table internally stored in the timing-signal generation section 43. The frequency division rate selected from the frequency division rate table is a frequency division rate corresponding to the bit clock frequency which has been received from the bit clock frequency determination section 42. The frequency division rate table internally stored in the timing-signal generation section 43 is one of the tables shown in
Subsequently, at the next step S5, the phase adjustment section 44 produces a result of determination as to whether or not the user has pressed the operation button 32. If the determination result produced at the step S5 indicates that the user has not pressed the operation button 32, the flow of the processing goes on to a step S7, skipping a step S6.
If the determination result produced at the step S5 indicates that the user has pressed the operation button 32, on the other hand, the flow of the processing goes on to the step S6 at which the phase adjustment section 44 shifts the phase of the timing signal received from the timing-signal generation section 43 while the user is pressing the operation button 32. As a result, the timing signal generated by the phase adjustment section 44 has a phase synchronized with the phase of a vertical synchronization signal which is used in an operation to display a 2-d video image on the TV receiver 21.
At the step S7, the phase adjustment section 44 supplies the timing signal to the timing-signal outputting section 45. As indicated by the flowchart shown in
The processing carried out at the steps S1 to S7 described above is performed repeatedly as long as the TV receiver 21 is transmitting an audio signal to the timing-signal generation apparatus 22 through the cable 31.
As described above, the timing-signal generation apparatus 22 is capable of generating a timing signal from a digital audio signal generated by the TV receiver 21 as a signal conforming to the IEC60958 and transmitting the timing signal to the shutter spectacles 23. Thus, it is possible to watch a 3-d stereoscopic video content by making use of the TV receiver 21 even if the TV receiver 21 does not have a function to output the timing signal.
It is to be noted that configuration elements each employed in the second embodiment to serve as an element identical with its counterpart included in the first embodiment described so far is denoted by the same reference numeral or the same reference notation as the counterpart. In addition, the explanation of the identical configuration elements is omitted in order to avoid duplications of descriptions.
In the 3-d stereoscopic video image watching system 51 shown in the diagram of
Thus, through the cable 31 connecting the intelligent shutter spectacles 61 to the digital audio output terminal 21a of the TV receiver 21, the intelligent shutter spectacles 61 receive a digital audio signal generated by the TV receiver 21 as a signal which conform to the IEC60958.
Like the timing-signal generation apparatus 22 shown in the block diagram of
In addition, the intelligent shutter spectacles 61 also employ an operation button 32′, a timing-signal outputting section 45′, a shutter driving section 71 and a shutter section 72 which are not included in the timing-signal generation apparatus 22 shown in the block diagram of
When the user presses the operation button 32′, a signal generated by the operation button 32′ is supplied to the phase adjustment section 44. That is to say, the operation button 32′ has a function identical with the function of the operation button 32 included in the timing-signal generation apparatus 22 shown in the block diagram of
The timing-signal outputting section 45′ passes on a timing signal received from the phase adjustment section 44 to the shutter driving section 71 through an electrical wire. That is to say, the timing-signal outputting section 45′ has a transmission destination and a transmission technique which are different from respectively the transmission destination and transmission technique of the timing-signal outputting section 45 included in the timing-signal generation apparatus 22 shown in the block diagram of
The shutter driving section 71 is a section for driving a right-eye shutter and a left-eye shutter which are each a liquid-crystal device employed in the shutter section 72. That is to say, on the basis of the timing signal received from the timing-signal outputting section 45′, the shutter driving section 71 generates a driving voltage to be applied to each of the liquid-crystal devices employed in the shutter section 72.
The shutter section 72 has the shutter for the right eye and the shutter for the left eye. Each of the shutter for the right eye and the shutter for the left eye is a liquid-crystal device having two electrodes. When the aforementioned driving voltage of approximately 10 to 20 V is applied between the two electrodes of a shutter for the left or right eye, the shutter operates independently of the other shutter. In the case of this second embodiment, when the shutter driving section 71 applies an electric potential difference of 0V between the two electrodes of a shutter for the left or right eye, the shutter is opened. When the shutter driving section 71 applies an electric potential difference of ±15V between the two electrodes of a shutter for the left or right eye, the shutter is closed.
Next, by referring to a flowchart shown in
The steps S11 to S16 of the flowchart shown in
At the step S17, the phase adjustment section 44 supplies the timing signal to the timing-signal outputting section 45′. As indicated by the flowchart shown in
Then, at the next step S18, on the basis of the timing signal received from the timing-signal outputting section 45′, the shutter driving section 71 generates a driving voltage to be applied to the liquid-crystal devices serving as the left-eye and right-eye shutters which are employed in the shutter section 72.
Subsequently, at the next step S19, driven by the driving voltage received from the shutter driving section 71, each of the left-eye and right-eye shutters employed in the shutter section 72 carries out closing and opening operations in accordance with the driving voltage. To put it in detail, when the shutter driving section 71 applies an electric potential difference of 0V between the two electrodes of a shutter for the left or right eye, the shutter is opened. When the shutter driving section 71 applies an electric potential difference of ±15V between the two electrodes of a shutter for the left or right eye, the shutter is closed. Finally, the processing sequence is ended.
The processing carried out at the steps S11 to S19 of the flowchart shown in
In accordance with the timing-signal generation processing represented by the flowchart shown in
In addition, in accordance with the second embodiment, the operation button 32′ used for adjusting the phase of the timing signal is provided on the intelligent shutter spectacles 61. Thus, the user-friendliness of the operation for adjusting the phase of the timing signal is enhanced.
It is to be noted that, for example, the shutter spectacles 23 employed in the 3-d stereoscopic video image watching system 11 shown in the diagram of
The third embodiment is different from the second embodiment in that, in the case of the 3-d stereoscopic video image watching system 81 according to the third embodiment, a wireless headphone system is provided between the TV receiver 21 and the intelligent shutter spectacles 61.
In addition, the 3-d stereoscopic video image watching system 81 also has a wireless headphone transmitter 91 which is connected by a cable 92 to the digital audio output terminal 21a of the TV receiver 21. The cable 92 has the same type as the cable 31 used in the 3-d stereoscopic video image watching system 11 shown in the diagram of
The wireless headphone 93 receives the audio signal transmitted by the wireless headphone transmitter 91 by radio communication and outputs the audio signal to speakers for the left and right ears. In addition, the wireless headphone 93 also supplies the audio signal to the intelligent shutter spectacles 61 through a cable not shown in the diagram of
Thus, also in the case of the third embodiment, the intelligent shutter spectacles 61 are capable of generating a timing signal from the audio signal received from the wireless headphone 93 and carrying out shutter operations in accordance with the timing signal. As a result, it is possible to watch a 3-d stereoscopic video content by making use of the TV receiver 21 even if the TV receiver 21 does not have a function to output a timing signal.
In addition, by virtue of the third embodiment, it is possible to construct a 3-d stereoscopic video image watching system by making use of an existing wireless head phone system.
It is to be noted that the wireless headphone 93 can also be provided with a function to generate a timing signal. In addition, it is also possible to make use of a head phone stereo system for receiving an audio signal through a wire as a substitute for the wireless headphone 93.
In addition to the shutter spectacles 23, the timing-signal generation apparatus 22 and the TV receiver 21 which are employed in the first embodiment shown in the diagram of
The reproduction apparatus 111 supplies 2-d video data to the TV receiver 21. As is obvious from the descriptions given earlier, the 2-d video data is data including left-eye and right-eye images which represent a 3-d stereoscopic video image. In addition, the reproduction apparatus 111 also supplies an audio signal associated with 2-d video images based on the 2-d video data as an audio signal conforming to the IEC60958 to the timing-signal generation apparatus 22 through the cable 31. Typical examples of the reproduction apparatus 111 are a Blu-ray (registered trademark) disc recorder functioning as a recording/reproduction apparatus and a PC (Personal Computer) serving as a recording/reproduction apparatus.
The timing-signal generation apparatus 22 connected by the cable 31 to a digital audio output terminal 21a of the reproduction apparatus 111 generates a timing signal from the audio signal received from the reproduction apparatus 111 through the cable 31 and transmits the timing signal to the shutter spectacles 23. It is to be noted that the digital audio output terminal 21a itself is not shown in the diagram of
As described above, the timing-signal generation apparatus 22 can also be applied to a configuration in which the reproduction apparatus 111 for displaying 2-d video images on the TV receiver 21 external to the reproduction apparatus 111 does not have a terminal for outputting a timing signal.
In accordance with the first to fourth embodiments described above, it is possible to watch a 3-d stereoscopic video content even if the apparatus for displaying video images does not have a function to output a timing signal.
In the first to fourth embodiments described above, the frequency of the timing signal generated by the timing-signal generation section 43 is 60 Hz or 59.94 Hz, either of which is a frequency determined in advance to serve as a frequency of the vertical synchronization signal used for displaying 2-d video signals on the TV receiver 21. It is to be noted, however, that the timing-signal generation apparatus 22 or the intelligent shutter spectacles 61 can be made capable of selecting the value 60 Hz or 59.94 Hz as the frequency of the timing signal generated by the timing-signal generation section 43.
It is also worth noting that, in this specification, steps of each of the flowcharts described above can be carried out not only in a pre-prescribed order along the time axis, but also concurrently or individually. In other words, even though the steps can of course be carried out in the pre-prescribed order along the time axis, the steps are not necessarily carried out in the pre-prescribed order along the time axis. For example, the steps can also be carried out concurrently or individually with demanded timings on an as-invoked basis.
It is also to be noted that the technical term ‘system’ used in this specification implies the configuration of a confluence including a plurality of apparatus.
In addition, implementations of the present invention are by no means limited to the first to fourth embodiments described above. That is to say, the first to fourth embodiments described above can be changed to a variety of modified versions within a range which does not deviate from essentials of the present invention.
The present application contains subject matter related to that disclosed in Japanese Priority Patent Application JP 2009-221299 filed in the Japan Patent Office on Sep. 25, 2009, the entire content of which is hereby incorporated by reference.
| Number | Date | Country | Kind |
|---|---|---|---|
| 2009-221299 | Sep 2009 | JP | national |
