JP2000004423A - Information reproduction device and method therefor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To output audio data seamlessly while synchronizing sound and pictures. SOLUTION: A video signal band expansion processing section 46 decodes a video signal in an information signal read from a recording medium 41 and including the video signal and an audio signal and a 1st audio signal band expansion processing section 54 and a 2nd audio signal band expansion processing section 55 decode independently the audio signal. A system controller 61 applies switching control to an audio switch section 56 so that a 1st recording position and a 2nd recording position discontinuous to the 1st recording position in the information signal are seamlessly connected while keeping synchronization between the video signal and the audio signal.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to an information signal reproducing apparatus and method for reproducing an information signal from a recording medium on which the information signal is recorded.

[0002]

2. Description of the Related Art Conventionally, an information reproducing apparatus for reproducing an information signal from a recording medium such as an optical disk has been provided. As such an information reproducing apparatus, for example, an apparatus having a configuration as shown in FIG. 11 can be mentioned.

That is, a recording / reproducing apparatus includes a recording medium 41 such as an optical disk on which an information signal is recorded, and a recording medium 41.
A disk / head control unit 42 for controlling heads, servos, and the like, and a reproduction data processing unit 43 for processing data reproduced from the recording medium 41.

[0004] A signal read from a recording medium 41 such as an optical disk controlled by a disk / head control unit 42 is supplied to a reproduction data processing unit 43.

[0005] In the reproduction data processing system 43, for example, EFM (eight to fourteen modulat) according to the reproduction format.
ion) Perform processing such as demodulation, error correction, and data rearrangement, and output the data to the data bus. The signal from the data bus is supplied to the memory 45.

The information reproducing apparatus includes a video buffer 45-1 which is a buffer for a video signal supplied from the reproduction data processing unit 43 via a data bus, and a video buffer 45.
-1 and a video signal D / A converter 49 for performing D / A conversion on the video signal from the video signal band extension processor 46.
And a video signal output processing unit 51 that processes and outputs a video signal from the video signal D / A conversion unit 49.

[0007] The memory 45 comprises a video buffer 45-1 and an audio buffer 45-2.

After the reproduced data is taken into the memory 45, the header is analyzed, the multiplexed signal is separated, and the video buffer 45-1 and the audio buffer 45-2 are separated.
Is allocated to each buffer. These buffers may be physically integrated in the same memory.

Further, in these buffers, the balance between consumption and supply is controlled so that the memory does not overflow / underflow, and the time of the video and the audio is adjusted using the time information of the header to generate a signal. Output.

In the video signal band extending section 46, a so-called M
PEG (moving picture experts group), so-called J
Band expansion is performed on PEG (joint phtographic coding experts group) and the like, and this signal is converted into an / A conversion unit 49.
Send to

The video signal D / A converter 49 performs D / A conversion on the signal from the video signal band extender 46 and sends the signal to the video signal output processor 51.

The video signal output processing unit 51 generates a video signal D /
A video signal obtained by subjecting the signal from the A conversion unit 49 to processing such as chroma encoding is output.

Further, the information reproducing apparatus includes an audio buffer 45-2 which is a buffer for an audio signal supplied from the reproduction data processing unit 43 via the data bus, and an audio buffer 4-2.
5-2, an audio signal band extension processing unit 54 that performs band extension processing on the audio signal, and an audio signal D / A conversion unit 5 that performs D / A conversion on the audio signal from the audio signal band extension processing unit 54.
7 and an audio signal output processing unit 58 that performs various processes on the audio signal from the audio signal D / A conversion unit 57 and outputs the processed signal.

The audio signal from the audio buffer 45-2 is
The audio signal band extending unit 54 or so-called ATRA
C, such as adaptive audio coding, so-called MPEG audio, so-called AC-3, etc.
The audio signal is sent to the D / A converter 57.

The audio signal D / A converter 57 performs D / A conversion on the signal from the audio signal band extender 54 and sends the signal to the audio signal output processor 58.

The audio signal output processing unit 58 outputs the audio signal D /
An audio signal obtained by performing various processes on the signal from the A conversion unit 57 is output.

The information reproducing apparatus includes a reproduction control signal input unit 62 to which the control for reproducing the information signal from the recording medium 41 is input, and each processing unit / control unit based on the signal from the reproduction control signal input unit 62. A system controller 61 for controlling the control unit.

Next, processing of an audio signal in such an information signal reproducing apparatus will be described.

FIG. 12 shows an audio signal during normal reproduction.
As shown in (1), generally, an audio signal is divided into blocks, and compression / expansion is performed in units of the blocks.

For example, in the case of adaptive speech coding, as shown by A in FIG. 12, a speech signal is blocked in units of 23 ms as a blocking time Tb. In the actual band expansion processing, the expansion operation is started after all the data for one block is input to the band expansion unit that performs band expansion.
The output as indicated by B in FIG. 12 is started. The time Tc in the figure is the time required for the calculation of the decompression process.

[0021]

By the way, in the information reproducing apparatus, special reproduction such as jump for discontinuously reproducing the video / audio signal from the first position to the second position may be performed.

When a jump is performed on a video signal of the NTSC system, one frame is 33.3 ms, and the jump can be performed only in units of this frame.

However, the time of one block of an audio signal and the time of one frame of a video signal are generally different.
For example, the video signal shown in A of FIG. 13 has a unit of 33.3 ms per frame, while the audio signal shown in B of FIG. 13 has a unit of 23 ms per block.

Therefore, in order to match the timing of the video signal and the audio signal before and after the jump, it is indispensable to insert a silent signal (mute) or the like.

For example, as shown by C in FIG.
It is assumed that special reproduction is performed to skip the fourth frame of the video signal indicated by A in FIG.

In this case, as shown at B in FIG. 13, there is no audio block corresponding to the fourth frame of the video signal shown at A in FIG. For this purpose, FIG.
In the audio signal shown in B in the figure, the fifth block and the sixth block which partially overlap the fourth frame of the video signal shown in A in the figure on the time axis have to be omitted.

That is, in the blocked audio signal indicated by D in FIG. 13, the fifth block and the sixth block indicated by “x” are omitted.

As described above, the video signal excluding the fourth frame shown in C of FIG. 13 and the blocked audio signal excluding the fifth and sixth blocks shown in D of FIG. A silence signal section is provided in order to maintain a synchronization relationship that is a time-direction correspondence between the signal and the audio signal.

That is, as shown by E in FIG. 13, a silent signal section Tm is inserted into the audio signal, and accordingly, the waveform of the audio signal shown by F in the figure has a value in the silent signal section Tm. It is zero.

When the silence signal section Tm is reduced,
After the jump, the synchronization relationship, which is the correspondence relationship between the audio signal and the video signal in the time direction, is shifted. Also,
If the first half of the five blocks of the audio signal is output in the silent signal section Tm, the seventh block of the audio signal cannot be expanded due to the calculation.

As described above, in the conventional information reproducing apparatus, when the jump of the special reproduction is performed, the synchronous relationship between the video signal and the audio signal is shifted or a silent signal section is generated. .

Further, in the case of n-times speed reproduction, which is a repetition of jumps, a similar problem exists for the above-mentioned reason. This is a major drawback in a disk device that can be expected to access at high speed.

The present invention has been made in view of the above circumstances, and when reproducing an information signal from a recording medium on which an information signal including a video signal and an audio signal is recorded, the audio signal and the video signal are combined. It is an object of the present invention to provide an information signal reproducing apparatus and method capable of seamlessly outputting a sound even when a discontinuous point such as a jump is reproduced, while maintaining a synchronous relationship.

[0034]

In order to solve the above-mentioned problems, an information reproducing apparatus according to the present invention comprises an information reproducing apparatus for transmitting an information signal from a recording medium on which an information signal including at least an encoded video signal and an audio signal is recorded. An information reproducing device for reproducing an information signal read from the recording medium, the image signal decoding device decoding a video signal included in the information signal, and an audio signal included in the information signal. Decoding means having a first audio signal decoding means for decoding an audio signal, and a second audio signal decoding means for decoding an audio signal included in the information signal independently of the first audio signal decoding means; Regarding a first recording position in an information signal and a second recording position discontinuous from the first recording position in the information signal, a synchronization relationship between the video signal and the audio signal is determined. While lifting, in which a control unit for the switching control to connect the video signal and the audio signal decoded by said decoding means to successively.

According to the present invention, there is provided an information reproducing method for reproducing an information signal from a recording medium on which an information signal including at least an encoded video signal and an audio signal is recorded.
A decoding step of decoding an information signal read from the recording medium, wherein the video signal decoding step decodes a video signal included in the information signal; and a first audio signal decodes an audio signal included in the information signal. A decoding step comprising: a decoding step; a second audio signal decoding step of decoding an audio signal included in the information signal independently of the first audio signal decoding step; and a first recording position in the information signal. And a second recording position that is discontinuous from the first recording position in the information signal, while maintaining a synchronous relationship between the video signal and the audio signal while maintaining the synchronization relationship between the video signal and the audio signal. And controlling the switching so that the signal and the audio signal are connected continuously.

As described above, according to the present invention, by independently decoding audio and synchronizing the audio output with video in advance, a seamless relationship is maintained between audio and video before and after switching. Audio can be output.

Further, the information reproducing apparatus according to the present invention is an information reproducing apparatus for reproducing an information signal from a recording medium on which an information signal including at least an encoded video signal and an audio signal is recorded. Storage means for storing, decoding means for decoding an information signal read from the recording medium, a video signal decoding means for decoding a video signal included in the information signal, a first recording position in the information signal, In the information signal, the first
Is a synchronization unit including the first recording position of the audio signal included in the information signal and the second recording of the audio signal included in the information signal with respect to the discontinuous second recording position. A decoding unit having an audio decoding unit that decodes a synchronization unit including a position at high speed and sequentially inputs the synchronization unit to the storage unit; and while maintaining a synchronization relationship between the video signal and the audio signal, the decoding unit Control means for controlling reading of the audio signal sent to the storage means by the audio signal decoding means so as to continuously connect the decoded video signal and audio signal.

An information reproducing method according to the present invention uses a storage means for storing information signals on a first-in first-out basis, and reads an information signal from a recording medium on which an information signal including at least an encoded video signal and an audio signal is recorded. In the information reproducing method for reproducing, a decoding step of decoding an information signal read from the recording medium, the video signal decoding step of decoding a video signal included in the information signal, and a first recording position in the information signal And a second recording position that is discontinuous from the first recording position in the information signal, and a synchronization unit including the first recording position of the audio signal included in the information signal and the synchronization unit included in the information signal. An audio decoding step of decoding a synchronization unit including the second recording position of the audio signal at a high speed and sequentially inputting the same to the storage means; The audio signal sent to the storage means in the audio signal decoding step so as to continuously connect the video signal and the audio signal decoded in the decoding step while maintaining the synchronization relationship between the signal and the audio signal. And a control step of controlling the reading of data.

As described above, according to the present invention, a high-speed audio signal decoding means and a first-in first-out storage means for storing the result are prepared, and only the audio data corresponding to the video is written on the storage means. By reading from the storage means in synchronization with the video, seamless audio can be output while maintaining the synchronous relationship between the audio and the video.

[0040]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of an information reproducing apparatus and method according to the present invention will be described in detail with reference to the drawings.

An information reproducing apparatus as shown in FIG. 1 will be described as a first embodiment of the present invention.

This information reproducing apparatus processes a data reproduced from the recording medium 41, a recording medium 41 on which an information signal is recorded, a disk / head control unit 42 for controlling heads, servos and the like in the recording medium 41. And a reproduction data processing unit 43.

On the recording medium 41, an information signal including at least an encoded video signal and audio signal is recorded. In the present embodiment, an optical disk is used as the recording medium 41.

The signal read from the recording medium 41 controlled by the disk / head control unit 42 is supplied to a reproduction data processing unit 43.

In the reproduction data processing system 43, for example, EFM (eight to fourteen modulat) according to the reproduction format
ion) Perform processing such as demodulation, error correction, and data rearrangement, and output the data to the data bus. The signal from the data bus is supplied to the memory 45.

Further, the information reproducing apparatus includes a video buffer 45 serving as a buffer for the video signal from the reproduced data processing section 43.
-1, a video signal band extension processing unit 46 that performs band extension processing on the video signal from the video buffer 45-1, and a video signal D / A that performs D / A conversion on the video signal from the video signal band extension processing unit 46. A converter 49 and video signal D / A converter 4
And a video signal output processing unit 51 for processing and outputting the video signal from the video signal output unit 9.

The memory 45 includes a video buffer 45-1, a first audio buffer 45-3, and a second audio buffer 4.
5-4.

After the reproduced data is loaded into the memory 45, the header is analyzed, the multiplexed signal is separated, and the video buffer 45-1 and the first audio buffer 45- are separated.
Distribution is performed to each of the third and second audio buffers 45-4. These buffers may be physically integrated in the same memory.

Further, the memory 45 controls the balance between consumption and supply so that the memory does not overflow / underflow, and uses the time information of the header to perform time alignment of audio with respect to video and to store data. The signal is output to the video signal band expansion unit 46 and the two audio signal band expansion processing units 54 and 55. Further, the memory 45 performs a data transmission process described later at the time of a jump.

In the video signal band expansion processing section 46, so-called MPEG (moving picture experts group) or so-called JPEG (joint phographic coding exper
ts group), and the video signal D
/ A conversion unit 49.

The video signal D / A converter 49 performs D / A conversion on the signal from the video signal band expansion processor 46 and sends the signal to the video signal output processor 51.

The video signal output processing section 51 outputs the video signal D /
A video signal obtained by subjecting the signal from the A conversion unit 49 to processing such as chroma encoding is output.

Further, the information reproducing apparatus performs band expansion processing on the first audio buffer 45-3 which is a buffer of the audio signal from the reproduction data processing unit 43 and the audio signal from the first audio buffer 45-3. The first audio signal band expansion processing unit 54 to be applied, the second audio buffer 45-4 which is also a buffer of the audio signal from the reproduction data processing unit 43, and the audio signal from the second audio buffer 45-5. A second audio signal band processing unit 55 that performs band expansion processing, and an audio switching unit 56 that switches signals from the first audio signal band expansion processing unit 54 and the second audio signal band expansion processing unit 55
An audio signal D / A conversion unit 57 for performing D / A conversion on the audio signal from the audio switching unit 56; and an audio signal output for performing various processing on the audio signal from the audio signal D / A conversion unit 57 and outputting the processed signal. And a processing unit 58.

The audio signal from the first audio buffer 45-3 is subjected to adaptive audio coding such as ATRAC, so-called MPEG, by a first audio signal band expansion processing unit 54.
The data is expanded in accordance with audio or a standard such as AC-3 and sent to the signal switching unit 56.

The audio signal from the second audio buffer 45-4 is also expanded by the second audio signal band compression unit 55,
The signal is sent to the signal switching unit 56. The audio switching unit 56 switches the outputs of the two audio signal band expansion processing units 54 and 55 in synchronization with the video signal.

The audio signal D / A conversion section 57 performs D / A conversion on the signal from the audio switching section 56 and sends the signal to the audio signal output processing section 58.

The audio signal output processing unit 58 outputs the audio signal D /
An audio signal obtained by performing various processes on the signal from the A conversion unit 57 is output.

The information reproducing apparatus includes a reproduction control signal input section 62 to which a control signal for reproducing the information signal from the recording medium 41 is input, and each processing section based on the signal from the reproduction control signal input section 62. / System controller 61 for controlling the control unit.

The system controller 61 controls various processing units / control units of the information reproducing apparatus, in addition to controlling special reproduction such as jumps to be described later.

Next, the jump processing of the video signal and the audio signal in the information reproducing apparatus will be described with reference to FIGS.

Here, in the video signal indicated by A in FIG. 2, it is assumed that the third frame is skipped from the second frame, and the video signal jumps discontinuously to the fourth frame.

That is, in the video signal A shown in FIG. 2, the first recording position is defined as the first recording position at the end of the second frame, and the second recording position is defined as the leading end of the fourth frame. Are continuously connected on the time axis.

As described above, the information reproducing apparatus expands the band of the audio signal from the first audio buffer 45-3.
, A second audio signal band expansion processor 55 that expands the band of the audio signal from the second audio buffer 45-4, a first audio signal band expansion processor 54, An audio switching unit 56 that switches the audio signal expanded by the audio signal band expansion processing unit 55 is provided.

Normally, the first audio signal band expansion processing section 54 is controlled so as to decode the audio signal while maintaining the synchronous relationship with the video signal. Here, the synchronization relationship is a correspondence relationship between the video signal and the audio signal in the time direction.

That is, the first audio signal band expansion processing section 54 holds the synchronization relationship with the video signal from the first frame to the third frame, which is 33.3 ms as one frame shown in A in FIG. Thus, the first to fifth blocks of the blocked audio signal indicated by B in the figure are extended in the time direction. From the first block to the fifth block,
This corresponds to the first to third frames of the video signal.

The blocked audio signal shown by B in FIG. 2 is expanded in the time direction as shown by C in FIG. 2 to be an audio signal having a waveform shown by D in FIG.

As described above, B to D in FIG. 2 show the expansion up to the fifth block of the audio signal corresponding to the third frame of the video signal shown in A in the figure.

When a jump instruction is given, the first audio signal band compression section 54 is controlled so as to decode the audio in synchronization with the video signal, but the second audio signal band expansion processing section 55 Then, audio data necessary for the video after the jump is supplied, and the audio decompression process is started so as to synchronize with the video after the jump.

That is, the second audio signal band expansion processing section 55 converts the seventh audio signal of the blocked audio signal shown in E in FIG. 2 corresponding to the fifth and subsequent frames of the video signal shown in A in FIG. From the block onward, the audio signal having the waveform shown by G in the figure is obtained by extending in the time direction as shown by F in the figure so as to maintain the synchronous relationship with the video signal.

E to G in FIG. 2 show the expansion of the seventh block of the audio signal after the fifth frame of the video signal shown in A of FIG.

As described above, when the jump instruction is given, the two audio expansion processing systems of the first audio signal band expansion processing unit 54 and the second audio signal band expansion processing unit 55 operate independently. Become.

The first audio signal band expansion processing section 54 synchronizes with the video before the jump and performs the second audio signal band expansion processing 5.
The fifth part is synchronized with the image after the jump.

Here, the synchronous relationship means a correspondence relationship between a video signal and an audio signal, that is, to match so-called picture and sound reproduction timings. This step S1
In 4, the synchronous relationship between the video signal and the audio signal after the jump is calculated so that the video and the audio are reproduced while maintaining the synchronous relationship before and after the jump even when the jump operation is performed.

Then, as shown by H in FIG. 2, the two signals of the first audio signal band expansion processing unit 54 and the second audio signal band expansion processing unit 55 are synchronized with the video switching point t1. Switch. After the switching, the second audio signal band expansion processor 55 performs normal audio processing, and the first audio signal band expansion processor 54 waits for the next jump.

At the time of video switching, it is also possible to perform processing such as cross-fade.

Next, the jump operation in the information reproducing apparatus will be described with reference to the flowchart shown in FIG.

In the first step S11, it is determined whether or not jump processing is performed. That is, when a jump instruction is received, the process proceeds to the next step S12, and otherwise, returns to this step S11.

In step S12, a first recording position in the video signal and a second recording position discontinuous from the first recording position, that is, a jump point are calculated. The frame number, time, etc. of these jump points are calculated. Then, the process proceeds to the next step S13.

In step S13, step S1
The block number, time, and the like are calculated for the two blocks of audio corresponding to the jump point of the video signal calculated in step 2, and in the next step S14, the synchronization relationship between the video signal and the audio signal after the jump is calculated. After the calculation, the process proceeds to step S15.

In step S15, up to the audio block at the jump point with respect to the currently used audio signal band expansion processor in the first audio signal band expansion processor 54 or the second audio signal band expansion processor 55. Is supplied to the memory 45. Also, an instruction to stop data supply after the jump point is given. Then, the process proceeds to the next step S16.

In step S 16, any of the first audio signal band expansion processing unit 54 or the second audio signal band expansion processing unit 55 that is not currently being used and is not used after the jump point. An instruction to supply data is issued to the memory 45. In addition, the synchronization relationship between the video and the audio after the jump point is calculated, the instruction is issued to the unused audio signal band extension processing unit 54, and the process proceeds to step S17.

These series of processes must be completed before the actual jump occurs. The order of these series of processes does not matter.

In step S17, it is determined whether or not the image is at a jump point. That is, when the jump point of the video comes, the process proceeds to step S18 as “YES”, and otherwise, the process returns to step S17 as “NO”.

In step S17, since the jump point of the video has come, an instruction for switching is issued to the audio switching unit 56. In the subsequent step S18, the audio signal band which is not currently used according to the instruction in step S17. Stop the decompression processing unit.

Thereafter, in the first audio signal band expansion processing section 54 and the second audio signal band expansion processing section 55,
What is currently used is no longer used, and what is not currently used is used.

That is, the first audio signal band compression section 54
In the second audio signal band compression unit 55, the used and unused audio signal band expansion processing units are switched, and wait for the next jump instruction.

In order to switch the image after the jump operation, the jump is performed after a predetermined time. Here, the predetermined time for switching the image requires, for example, about several fields.

As described above, in the present embodiment, an information signal is reproduced from the recording medium 41 on which an information signal including at least an encoded video signal and an audio signal is recorded.

In this embodiment, the part for decoding the information signal obtained from the storage means 41 via the reproduction data processing part 43 and the memory 45 includes a video signal band expansion processing part 46 for decoding a video signal, It has a first audio signal band expansion processing unit 54 for decoding a signal, and a second audio signal band expansion processing unit 55 for decoding an audio signal independently of the first audio signal band expansion processing unit 54. I have.

In the present embodiment, the system controller 61 controls the first information signal from the recording medium 41 based on the control signal from the reproduction control signal input section 62.
The decoded video signal and the audio signal are continuously recorded while maintaining the synchronization relationship between the video signal and the audio signal for the recording position of the second recording position and the second recording position that is discontinuous from the first recording position. The audio switching unit 56 is controlled so as to be connected.

Here, a frame which is a synchronization unit of a video signal included in the information signal reproduced from the recording medium 41,
The blocks, which are synchronization units of the audio signal included in the information signal, have different lengths, and the first recording position and the second recording position respectively correspond to frame boundaries of the video signal. ing.

Then, the first audio signal band expansion processing section 5
Reference numeral 4 denotes an audio signal block including the first recording position of the video signal, and reference numeral 2 denotes an audio signal band extension processing unit 55 which decodes the audio signal block including the second recording position of the video signal. Reference numeral 61 controls the decoded video signal and audio signal so as to continuously connect the first recording position and the second recording position, while maintaining the synchronous relationship between the video signal and the audio signal.

Next, as a second embodiment of the present invention,
The information reproducing apparatus shown in FIG. 4 will be described. For the sake of simplicity, the same parts as those in the first embodiment are denoted by the same reference numerals, and description thereof is omitted.

The information reproducing apparatus includes a recording medium 41 on which an information signal is recorded, a disk / head control unit 42 for controlling the head and servo of the recording medium 41, and a reproducing apparatus for processing data reproduced from the recording medium 41. Data processing unit 4
And 3.

The information reproducing apparatus has a video buffer 45 which is a buffer for the video signal from the reproduced data processing section 43.
-1, a video signal band extension processing unit 46 that performs band extension processing on the video signal from the video buffer 45-1, and a video signal D / A that performs D / A conversion on the video signal from the video signal band extension processing unit 46. A converter 49 and video signal D / A converter 4
And a video signal output processing unit 51 for processing and outputting the video signal from the video signal output unit 9.

The memory 45 is composed of a video buffer 45-1 and an audio buffer 45-5.

After the reproduced data is taken into the memory 45, the header is analyzed, the multiplexed signal is separated, and the video buffer 45-1 and the audio buffer 45-5 are separated.
Are allocated to the respective buffers.

Further, the memory 45 controls the balance between the consumption and the supply so that the memory does not overflow / underflow, and uses the time information of the header to adjust the time of the audio and the data to the image signal. Output to the band expansion system and the audio signal band expansion system. Further, the memory 45 performs a data transmission process at the time of jump, as described later.

Further, the information reproducing apparatus includes an audio buffer 4 serving as a buffer for the audio signal from the reproduced data processing section 43.
5-5, an audio signal band expansion processor 64 for performing band expansion processing on the audio signal from the audio buffer 45-5, and an audio signal from the audio signal band expansion processor 64 controlled by a write data instruction. First in first out (firs
t in first out (FIFO) storage means
FO63 and the audio signal from the audio output FIFO63
The audio signal D / A converter 57 performs an A / A conversion, and an audio signal output processor 58 performs various processes on the audio signal from the audio signal D / A converter 57 and outputs the processed signal.

The audio signal is converted to a high-speed audio signal band extender 6.
4, the data is subjected to so-called adaptive audio conversion or decompression corresponding to the so-called MPEG audio, so-called AC-3 standard, etc., and transmitted to the FIFO 63.
This FIFO 63 may be composed of a RAM or the like. The meaning of this high speed will be described later.

It is assumed that the FIFO 63 has a function of writing only specified data according to an external instruction.

The signal output from FIFO 63 is subjected to D / A conversion in audio signal D / A conversion section 57 and sent to audio signal output processing section 58.

The audio signal output processing section 58 outputs the audio signal D /
An audio signal obtained by performing various processes on the signal from the A conversion unit 57 is output.

The information reproducing apparatus has a reproduction control signal input section 62 to which control for reproducing the information signal is inputted.
And a system controller 61 that controls each processing unit / control unit based on a signal from the reproduction control signal input unit 62.

The system controller 61 controls various processing units / control units of the information reproducing apparatus in addition to controlling special reproduction such as a jump described later.

Next, the processing of a video signal and an audio signal in the information reproducing apparatus will be described with reference to FIGS.

Here, it is assumed that the video signal indicated by A in FIG. 5 jumps from the third frame to the fifth frame discontinuously.

As described above, the information reproducing apparatus is provided with the audio signal band expansion processing section 64 which operates at a high speed or higher at a magnification determined by the reproduction speed and the FIFO 53 which is a first-in first-out storage means, as described later. .

In a normal operation, all outputs from the audio signal band expansion processing section 64 are input to the FIFO 63, and are read from the FIFO 63 so as to synchronize with the video. That is, the video signal is time-expanded by the FIFO 63.

When a jump instruction is given, the audio signal band expansion processing section 64 and the FIFO 63 are controlled to operate as follows.

For the processing of the audio block immediately before the jump, the audio signal band expansion processor 64 decodes all the data and sends the data from the block head data to the switching point to the FIFO 63.

That is, up to the fifth block of the block audio signal shown in B in the figure corresponding to the third frame of the video signal shown in A in FIG. 5, as shown in C in the figure. The decoding is performed by the fifth section, and the specific waveform is as shown in D in the figure.

Here, since the audio signal band expansion processing section 64 in the second embodiment executes processing at a high speed, the decoded audio signal can be processed in a short time with respect to the synchronization time of the audio signal block. There are gaps between the sections of the decoded audio signal.

Then, the portion of the audio signal corresponding to the fifth block as shown at D in FIG. 5 is input to the FIFO 63 as shown at E in the diagram.

Next, in the processing of the audio block immediately after the jump, the audio signal band expansion processing section 64 decodes all the data and sends the data after the switching point to the FIFO 63.

That is, the seventh and subsequent blocks of the audio signal shown in B in the drawing corresponding to the fifth and subsequent frames of the video signal shown in A in FIG. The subsequent sections are decoded thereafter, and the specific waveforms are as shown in D in the figure.

In the decoded audio signal shown in C of FIG. 5 corresponding to the seventh and subsequent blocks shown in B of FIG. 5, there is a gap between the sections for the same reason as described above. ing.

Then, the portion of the audio signal corresponding to the seventh and subsequent blocks as shown at D in FIG. 5 is input to the FIFO 63 as shown at E in the diagram.

Here, a period t0 including the rear part of the fifth section and the front part of the seventh section in the audio signal indicated by D in FIG.
Is not an unnecessary part, and writing to the FIFO 64 is not performed.

As for the reading from the FIFO 64, the data is sequentially read from the FIFO 64 so as to be synchronized with the video as in the normal operation.

That is, the audio signal input as shown at E in FIG. 5 is read out in synchronization with the video as shown at F in the figure. In the FIFO 63, since the audio signal decoded at high speed is expanded in the time direction and read out while maintaining the synchronous relationship with the video signal, the gap in the discrete audio signal shown by E in FIG. are doing.

Next, conditions for performing the jump operation in the high-speed audio signal band signal processing section 64 and the FIFO 63 as described above will be described. By analyzing this worst case, the audio signal band signal processing unit 6
4 gives the significance of fast speed.

The worst case where the burden is the largest is when only one sample is needed in the blocks immediately before and immediately after the jump. In this worst case, the entire block just before and after the jump must be decoded to get just one sample.

Specifically, in the audio signal including the first audio block section to the fourth audio block section indicated by A in FIG. 6, as shown in B in the figure, the first one sample of the second audio block is obtained. A section from the sample following S1 to the sample before the last sample S2 of the third voice block section is defined as a section to be skipped.

In this case, "2 blocks + 1" comprising the first audio block, the sample S1 of the second audio block, the sample S2 of the third audio block, and the fourth audio block.
It is necessary to decode four blocks of data for a "two sample" section.

Considering that the block size of the audio signal is usually larger than the sample, the audio signal band expansion processing unit 64 needs to execute processing at a high speed of 2 (= 4/2) times. .

However, since this value also depends on the size of the FIFO 63 and the supply capacity of the audio buffer 45-5, it may be possible to configure the information reproducing apparatus with a magnification lower than this value.

Next, the operation of the information reproducing apparatus will be described with reference to the flowchart shown in FIG.

In the first step S21, it is determined whether or not jump processing is performed. That is, when the jump process comes, the process proceeds to step S22 as “YES”, and otherwise, the process returns to step S21 as “NO”.

In step S22, the frame number,
A jump point of the video such as time is calculated, and in the subsequent step S23, a block number, a time, and the like of two blocks of audio corresponding to the video are calculated. Then, it proceeds to the next step S24.

In step S25, the synchronous relationship between the audio and the video after the jump is calculated. In step S24, an invalid sample area or an effective sample area in two audio blocks corresponding to the video is calculated. Proceed to S26.

At step S26, the memory 45 is instructed to supply data up to the audio block at the jump point to the audio signal band extending section 64. At the next step S27, an invalid sample area is instructed to the FIFO 63. I do. Then, the process proceeds to step S28.

In step S28, the memory 45 is instructed to stop supplying data after the jump point to the audio signal band extending unit, and in the next step S29, an invalid sample area is instructed to the FIFO 63. Then, this series of steps ends.

As described above, in the second embodiment, an information signal is reproduced from a recording medium 41 on which an information signal including at least an encoded video signal and an audio signal is recorded.

That is, in the present embodiment, with respect to the information signal provided from the recording medium 41 via the reproduction data processing unit 43 and the memory 45, the video signal included in the information signal is transmitted to the video signal band expansion processing unit 46. The audio signal included in the information signal is decoded by a first recording position and a second recording position that is discontinuous with the first recording position of the information signal.
The audio signal of the synchronization unit including the first recording position and the audio signal of the synchronization unit including the second recording position are decoded at a high speed by the audio signal band expansion processing unit 64, and are respectively first-in first-out. FIF is a storage means of
It is sequentially input to O63.

In the present embodiment, based on the control from the reproduction control signal input unit 62, the system controller 61 holds the synchronous relationship between the video signal and the audio signal, while maintaining the synchronous relationship between the video signal and the audio signal. The audio signal band expansion processor 64 sends the video signal and the audio signal decoded by the audio signal band expansion processor 64
The reading of the audio signal sent to the IFO 63 is controlled.

Here, the frame which is the synchronization unit of the video signal and the block which is the synchronization unit of the audio signal have different lengths, and the first recording position and the second recording position are different from each other. , Respectively, correspond to the frame boundaries of the video signal.

Then, the audio signal band expansion processing section 64 decodes the audio signal block including the first recording position, which is set for the frame boundary of the video signal, and inputs the decoded block to the FIFO 63, where the video signal frame is expanded. , The block of the audio signal including the second recording position discontinuously taken from the first recording position is decoded and input to the FIFO 63, and the system controller 61 determines the synchronization relationship between the video signal and the audio signal. While controlling the reading from the FIFO 63 so that the decoded video signal and audio signal are continuously connected at the first and second recording positions.

In the present embodiment, the audio signal band extension processing section 63 performs the first
And the block including the second recording position are decoded so as not to be delayed from the point in time when the first recording position and the second recording position in the video signal are continuously connected. Decoding at a very high speed.

Next, a modified example of the above-described second embodiment will be described.

In this modification, as shown in FIG. 8, an audio signal delay detector 65 is provided in the information signal reproducing apparatus of the second embodiment.
Has been added. This audio delay detection unit 65
It may be configured integrally with O63.

The audio delay detecting section 65 determines the frequency of the F based on the signals from the audio signal band extension processing section 64 and the FIFO 63.
The delay in the IFO 63 is detected. The synchronization relationship between video and audio is calculated from the output of the audio delay detection unit 65.

The other parts of this modified example are described below.
Since the second embodiment is the same as the second embodiment, the same reference numerals are given and the description will be omitted.

Next, a first specific example of voice delay detection will be described with reference to FIG.

In the first specific example, FIFO 6
3 and the audio delay detection unit 65 are integrally formed.

In the first specific example, the FIFO 63 and the audio delay detection unit 65 receive the m-bit time stamp and the n-bit audio signal from the audio signal band expansion processing unit 64, It is configured as an n + m-bit d-stage FIFO 81 that outputs a bit audio signal to the audio signal D / A converter.

In the FIFO 81, writing is controlled by an input control signal.

In the first specific example, the delay amount of each audio data can be calculated by writing the time stamp information of the audio data together with the FIFO with an increased bit width.

Next, a second specific example of voice delay detection will be described with reference to FIG.

In the second specific example, the FIFO 6
3 and the audio delay detection unit 65 are integrally formed.

In the second specific example, a write address generator 86 for generating a write address, a read address generator 87 for generating a read address, and an n-bit audio signal from the audio signal band expansion processor 64 are input. Then, an n × d-bit R corresponding to a d-stage FIFO in which an n-bit audio signal is output to the audio signal D / A conversion unit 57
AM85.

In the RAM 85, the audio signal is written and read according to the write address and read address from the write address generator 86 and the read address generator 87, and the write control signal.

In the second specific example, a first thinning section 83 and a second thinning section which thin out audio samples to 1 / k, respectively, are thinned to 1 / k for writing and reading. A RAM 82 corresponding to a d / k-stage FIFO that receives a time stamp from the audio signal band expansion processing unit 64 based on the time stamp and outputs the time stamp to the audio signal D / A conversion unit 58 is provided.

In the first embodiment, the delay amount can be obtained for each audio sample. However, in the second embodiment, when accuracy is not required, the time stamp information may be thinned out and used. I just need. This can reduce the amount of memory used.

The second specific example shows a method of writing and reading out time stamp information by thinning it to 1 / k.

In the first and second specific examples, modifications of the second embodiment have been described. In the second embodiment, FIFO processing is used to process audio signals.
Since the delay 63 is used, it is necessary to accurately grasp the delay in the FIFO 63.

That is, if the total number of data input to the FIFO 63 and the total number of data extracted from the FIFO 63 have been counted, the delay can be calculated. Can not. The present modification prevents such a problem.

As described above, this embodiment includes a plurality of audio signal band extending units and an audio signal switching unit.
Alternatively, by providing a high-speed audio signal band expansion processing unit and FIFO, even during special reproduction such as a jump, seamless audio is output while maintaining a synchronous relationship between video and audio.

[0159] The present invention is not limited to the above embodiment. For example, in the present invention, a magnetic tape other than an optical disk can be used as a recording medium.

[0160]

As described above, according to the present invention, by seamlessly decoding the sound before and after the jump, it is possible to output seamless sound while maintaining the synchronous relationship between the sound and the video.

Also, according to the present invention, by providing a FIFO for performing decoding at a high speed and storing the result of decoding, it is possible to substantially independently decode the sound before and after the discontinuity point. Seamless audio can be output while maintaining the synchronous relationship between the video and the video.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating a configuration of a first embodiment of an information reproducing apparatus.

FIG. 2 is a diagram showing processing of a video signal and an audio signal in the information reproducing apparatus of FIG. 1;

FIG. 3 is a flowchart showing steps of processing in the information reproducing apparatus of FIG. 1;

FIG. 4 is a block diagram illustrating a configuration of a second embodiment of the information reproducing apparatus.

FIG. 5 is a diagram showing processing of a video signal and an audio signal in the information reproducing apparatus of FIG. 4;

6 is a diagram illustrating a worst case in the information reproducing apparatus of FIG.

FIG. 7 is a flowchart showing processing steps in the information reproducing apparatus of FIG. 4;

FIG. 8 is a block diagram showing a modification of the information reproducing apparatus of FIG. 4;

FIG. 9 is a block diagram illustrating a first specific example of a delay detection unit.

FIG. 10 is a block diagram illustrating a second specific example of the delay detection unit.

FIG. 11 is a block diagram showing a configuration of a conventional information reproducing apparatus.

FIG. 12 is a time chart showing an audio processing operation during normal reproduction in a conventional information reproducing apparatus.

FIG. 13 is a time chart showing a problem during special reproduction in a conventional information reproducing apparatus.

[Explanation of symbols]

41 recording medium, 46 video signal band extension processing section,
4,55 audio signal band extension processing unit, 56 audio switching unit, 61 system controller, 64 audio output F
IFO, 64 audio signal band expansion processing unit, 65 audio delay detection unit

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 5C053 FA23 GB10 GB11 GB37 HA33 HA40 JA07 KA01 KA08 KA19 KA24 KA25 5D044 AB05 AB07 BC02 CC04 DE03 DE17 FG10 FG21 GL02 JJ07

Claims (10)

[Claims] 1. An information reproducing apparatus for reproducing an information signal from a recording medium on which an information signal including at least an encoded video signal and an audio signal is recorded, wherein the decoding means decodes the information signal read from the recording medium. A video signal decoding unit for decoding a video signal included in the information signal, a first audio signal decoding unit for decoding an audio signal included in the information signal, and the first audio signal decoding unit. Decoding means having second audio signal decoding means for independently decoding an audio signal included in the information signal; a first recording position in the information signal; and a first recording position in the information signal. With respect to the discontinuous second recording position, the video signal and the audio signal decoded by the decoding means are continuously connected while maintaining the synchronous relationship between the video signal and the audio signal. Information reproducing apparatus characterized by a control means for controlling switching on so that. 2. A frame which is a synchronization unit of the video signal and a block which is a synchronization unit of the audio signal have different lengths, and the first recording position and the second recording position are different from each other. Respectively corresponding to a frame boundary of the video signal, wherein the first audio signal decoding means decodes an audio signal block including a first recording position of the video signal, and wherein the second audio signal decoding means Decodes a block of an audio signal including a second recording position of the video signal, and the control unit decodes the block by the decoding unit while maintaining a synchronization relationship between the video signal and the audio signal. 2. The information reproducing apparatus according to claim 1, wherein the video signal and the audio signal are controlled so that the first recording position and the second recording position are continuously connected. 3. An information reproducing method for reproducing an information signal from a recording medium on which an information signal including at least an encoded video signal and an audio signal is recorded, wherein a decoding step of decoding the information signal read from the recording medium is performed. A video signal decoding step of decoding a video signal included in the information signal, a first audio signal decoding step of decoding an audio signal included in the information signal, and the first audio signal decoding step. A second audio signal decoding step of independently decoding an audio signal included in the information signal; a first recording position in the information signal; and a first recording position in the information signal. For the discontinuous second recording position, the video signal and the audio signal decoded in the decoding step are continuously connected while maintaining the synchronous relationship between the video signal and the audio signal. Information reproducing method characterized by a control step of controlling switched so that. 4. A frame which is a synchronization unit of the video signal and a block which is a synchronization unit of the audio signal have different lengths, and the first recording position and the second recording position are different from each other. Respectively corresponding to a frame boundary of the video signal, the first audio signal decoding step decodes an audio signal block including a first recording position of the video signal, and the second audio signal decoding step Decodes a block of an audio signal including a second recording position of the video signal, and the control step decodes the block by the decoding unit while maintaining a synchronization relationship between the video signal and the audio signal. 4. The information reproducing method according to claim 3, wherein the video signal and the audio signal are controlled so that the first recording position and the second recording position are continuously connected. 5. An information reproducing apparatus for reproducing an information signal from a recording medium on which an information signal including at least an encoded video signal and an audio signal is recorded, wherein: a storage means for storing the information signal on a first-in first-out basis; Decoding means for decoding an information signal read out of the information signal, a video signal decoding means for decoding a video signal included in the information signal, a first recording position in the information signal, and a first recording in the information signal. Regarding the position and the discontinuous second recording position, the synchronization unit including the first recording position of the audio signal included in the information signal and the second recording position of the audio signal included in the information signal are defined. A decoding unit having an audio decoding unit that decodes the synchronization unit at high speed and sequentially inputs the synchronization unit to the storage unit; and holds a synchronization relationship between the video signal and the audio signal. While
Control means for controlling reading of the audio signal sent to the storage means by the audio signal decoding means so as to continuously connect the video signal and the audio signal decoded by the decoding means. Information reproducing device. 6. A frame which is a synchronization unit of the video signal and a block which is a synchronization unit of the audio signal have different lengths, and the first recording position and the second recording position are different from each other. The audio signal decoding unit decodes a block of the audio signal including the first recording position taken on the boundary of the frame of the video signal, and stores the block in the storage unit. Decoding a block of an audio signal including a second recording position that is discontinuously taken from the first recording position with respect to a frame boundary of the video signal and inputting the decoded signal to the storage unit; Holds the video signal and the audio signal decoded by the decoding means while maintaining the synchronization relationship between the video signal and the audio signal so that the video signal and the audio signal are continuously connected at the first and second recording positions. hand 6. The information reproducing apparatus according to claim 5, wherein reading from the stage is controlled. 7. The high-speed means that a block including the first recording position in the decoded audio signal and a block including the second recording position are defined as the first recording position in the video signal. 7. The information reproducing apparatus according to claim 6, wherein the decoding speed is such that decoding is performed so as not to be delayed from a point in time when the second recording position is continuously connected. 8. An information reproducing method for reproducing an information signal from a recording medium on which an information signal including at least an encoded video signal and an audio signal is recorded by using storage means for storing the information signal on a first-in first-out basis. A decoding step of decoding an information signal read from a medium, the decoding step of decoding a video signal included in the information signal; and a first recording position in the information signal and a first recording position in the information signal. The recording position is a discontinuous second recording position, a synchronization unit including the first recording position of the audio signal included in the information signal, and the second recording position of the audio signal included in the information signal. And an audio decoding step of decoding the synchronization unit including the video signal at high speed and sequentially inputting the synchronization unit to the storage means; and maintaining a synchronization relationship between the video signal and the audio signal. While,
Controlling the reading of the audio signal sent to the storage means in the audio signal decoding step so as to continuously connect the video signal and the audio signal decoded in the decoding step. Information reproducing device. 9. A frame, which is a synchronization unit of the video signal, and a block, which is a synchronization unit of the audio signal, have different lengths, and the first recording position and the second recording position are different from each other. Corresponding to the frame boundaries of the video signal, and the audio signal decoding step decodes the audio signal block including the first recording position taken on the video signal frame boundaries, and stores the decoded block in the storage means. Inputting and decoding a block of an audio signal including a second recording position discontinuously taken from the first recording position with respect to a frame boundary of the video signal, and inputting the decoded signal to the storage means; Stores the video signal and the audio signal decoded in the decoding step so as to be continuously connected at the first and second recording positions while maintaining a synchronous relationship between the video signal and the audio signal. hand 9. The information reproducing method according to claim 8, wherein reading from a stage is controlled. 10. The high-speed means that a block including the first recording position in the decoded audio signal and a block including the second recording position correspond to the first recording position in the video signal. 10. The information reproducing method according to claim 9, wherein the decoding speed is such that the decoding is performed so as not to be delayed from a point in time when the second recording position is continuously connected.