JP2002074920A - Information processor, information processing method and recording medium - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain an information processor, an information processing method and a recording medium by which the reproducing time can easily and relatively accurately to displayed. SOLUTION: While expanding and reproducing audio data which are compressed by an MPEG Audio layer III, the bit rates of frames that are being reproduced is obtained from header information for every prescribed time and accumulated (a step 114). Then, the total number of bytes of the transferred (reproduced) audio data is computed (a step 118). Based on the accumulated bit rates, an average value of the bit rates is computed (a step 120). Then, based on the average value of the computed bit rates and the total byte number of the audio data, a reproducing time is computed (a step 122). Then, the computed reproducing time is displayed (a step 124).

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an information processing apparatus, an information processing method, and a recording medium, and more particularly, expands and reproduces data compressed by a compression method in which a bit rate can be set for each frame. At this time, the present invention relates to an information processing apparatus, an information processing method, and a recording medium for displaying a reproduction time of the data.

[0002]

2. Description of the Related Art In recent years, MP3 (Moving Picture Expert Group A) has been used as a compression method (encoding method) for audio data.
audio layer III) is widely used, and MP3
Many music players (hereinafter, referred to as "MP3 players") corresponding to the audio data (hereinafter, referred to as "MP3 format data") compressed by the manufacturer are also provided.

By the way, in MP3 players, generally, M
It has the function of decompressing and reproducing the audio data compressed in P3 and displaying the reproduction time on a display device such as a liquid crystal display. The reproduction time T at this time is derived by the following equation (1). Was.

Reproduction time T = BNＴ (FBR ÷ 8) (1) Here, BN is a CD-ROM (Compact Disc Read On)
ly Memory) Total number of bytes of data transferred from a CD-ROM decoder, which is a decoder of a Compact Disc (CD) on which audio data compressed using MP3 is recorded, to an MP3 decoder that decodes MP3 format data And FBR is a bit rate (transfer rate) when the time is first displayed.

That is, conventionally, the reproduction time T is derived by fixedly applying the bit rate at the time of first performing the time display.

[0006]

However, in the technique for deriving the reproduction time by fixedly applying the bit rate at the time of first performing the time display as described above, the MP3 encoded by changing the bit rate is used. During the reproduction of the format data, if the bit rate changes from the bit rate when the time is first displayed, there is a problem that the derived reproduction time cannot be made accurate.

[0007] That is, in order to enable data to be stored efficiently, MP3 has a bit rate that can be changed for each frame (so-called VBR).
(Variable Bit Rate) method).
When reproducing three-format data, the technique of deriving the reproduction time by fixedly applying the bit rate at the time of first performing the time display described above cannot make the reproduction time accurate.

Here, it is possible to read out the bit rates of all the frames in advance and derive an accurate reproduction time based on these bit rates. In this case, the CPU ( Central Processing Uni
t), there is a problem that a high processing capability is required for the microcontroller and the like, and the apparatus becomes expensive.

There is also a problem that this method cannot be easily applied to fast-forward or fast-reverse MP3 format data during playback.

The present invention has been made to solve the above problems, and provides an information processing apparatus, an information processing method, and a recording medium that can easily and relatively accurately display a reproduction time. With the goal.

[0011]

According to a first aspect of the present invention, there is provided an information processing apparatus, comprising: a compression method in which a bit rate can be set for each frame and the bit rate is recorded for each frame. What is claimed is: 1. An information processing apparatus for displaying a reproduction time of said data when decompressing and reproducing the compressed data, comprising: a bit rate obtaining means for obtaining a bit rate of data being reproduced at predetermined time intervals; And a data amount obtaining unit for obtaining a data amount from the frame being reproduced to the frame being reproduced, and deriving the reproduction time based on an average value of the bit rate obtained by the bit rate obtaining unit and the data amount obtained by the data amount obtaining unit. And display means for displaying the reproduction time derived by the derivation means.

According to the first aspect of the present invention, when expanding and reproducing data compressed by a compression method in which a bit rate can be set for each frame and a bit rate is recorded for each frame, The playback time of the data is displayed. Here, the data includes audio data,
All data for which reproduction processing such as video data is executed is included. In addition, the compression method includes MPEG-2 AA
C (Moving Picture Expert Group-2 Advanced Audio C
oding), MPEG-4 and the like.

Further, according to the first aspect of the present invention, the bit rate of the data being reproduced is acquired at predetermined time intervals by the bit rate acquiring means, and the data amount from the first frame to the frame being reproduced is acquired by the data amount acquiring means. Is obtained.

Further, in the information processing apparatus according to the first aspect,
The deriving unit derives a reproduction time based on the average value of the bit rate obtained by the bit rate obtaining unit and the data amount obtained by the data amount obtaining unit, and displays the derived reproduction time by the display unit. . In addition, as a display device on which the reproduction time is displayed by the display means, all display devices such as a liquid crystal display, a cathode ray tube display, a plasma display, and an EL display can be applied. In addition, the average value of the bit rates includes all average values such as the arithmetic average value and the geometric mean value of the bit rates acquired so far.

As described above, according to the information processing apparatus of the first aspect, the bit rate of the data being reproduced is obtained at predetermined time intervals, and the data amount from the first frame to the frame being reproduced is obtained. Since the playback time is derived based on the average value of the bit rates obtained at predetermined time intervals and the data amount and the derived playback time is displayed, the playback time is fixedly applied by using a single bit rate. The reproduction time can be accurately derived as compared with the case where the reproduction time is derived, and the reproduction time can be easily derived as compared with the case where the reproduction time is derived using the bit rates in all the frames. As a result, the reproduction time can be displayed simply and relatively accurately.

[0016] As in the second aspect of the invention, MP3 can be applied as a compression method in the first aspect of the invention. Here, MP3 contains M
PEG-1 Audio Layer III, MPEG-2
Audio Layer III and MPEG-2.5 Au
dio.

According to the second aspect of the present invention, the reproduction time of data compressed by MP3 can be displayed easily and relatively accurately.

Further, as in the third aspect of the present invention, a moving average value of the bit rate can be applied as the average value of the bit rate in the first or second aspect of the invention.

According to the information processing apparatus of the third aspect, the deriving means of the first or second aspect of the present invention provides the moving average value of the bit rate obtained by the bit rate obtaining means and the data amount obtaining means. The reproduction time is derived based on the obtained data amount.

As described above, according to the information processing apparatus of the third aspect, the moving average value of the bit rate is applied as the average value of the bit rate of the present invention. The average value of the rate can be easily derived.

On the other hand, in order to achieve the above object, an information processing method according to claim 4, wherein the bit rate can be set for each frame and the data compressed by a compression method in which the bit rate is recorded for each frame. An information processing method for displaying a reproduction time of the data when decompressing and reproducing the data, wherein a bit rate obtaining step of obtaining a bit rate of the data being reproduced every predetermined time; and A data amount acquisition step of acquiring a data amount up to a frame, and a derivation step of deriving the reproduction time based on an average value of the bit rate acquired by the bit rate acquisition step and the data amount acquired by the data amount acquisition step. And a display step of displaying the reproduction time derived in the deriving step.

Therefore, according to the information processing method of the fourth aspect, the operation is the same as that of the first aspect of the present invention. Then, the playback time can be accurately derived, and the playback time can be easily derived as compared with the case where the playback time is derived using the bit rates of all the frames. As a result, The reproduction time can be displayed easily and relatively accurately.

The computer-readable recording medium according to the fifth aspect is a recording medium on which a program for causing a computer to operate in the same manner as the first aspect of the invention is recorded. Electric
ally Erasable and Programmable Read Only Memor
y), storage elements such as flash memory, portable recording media such as floppy disks, CD-ROMs, magneto-optical disks, magnetic tapes, and fixed recording media such as hard disks, or server computers connected to a network An external storage device or the like provided in the like can be applied.

[0024]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment in which the present invention is applied to a CD (Compact Disc) player will be described below in detail with reference to the drawings. First, referring to FIG.
The configuration of the CD player 10 according to the present embodiment will be described. The CD player 10 is a CD-DA
(Compact Disc-Digital Audio) format CD with audio data recorded and CD-ROM format with audio data compressed using MP3 recorded
The digital information recorded in the .. can be read and reproduced. The MP3 has MPE
G-1 Audio Layer III, MPEG-2 Au
Dio Layer III and MPEG-2.5 Audio
o.

As shown in FIG. 1, C according to the present embodiment
The D player 10 includes a spindle 12, which is a rotation axis of the CD 80, a spindle motor 14 for rotating the spindle 12, a pickup 16 for reading data recorded on the CD 80, and a slide motor 18 for sliding the pickup 16. And a servo circuit 20. Here, the spindle motor 14 and the slide motor 18 are connected to a servo circuit 20, and the servo circuit 20 controls the operations of the spindle motor 14 and the slide motor 18.

The CD player 10 includes the RF amplifier 2
2, CD-DSP (Digital Signal Processor) 24
A CD-ROM decoder 26 to which a RAM (Random Access Memory) 28 is connected, an MP3 decoder 30,
Digital / analog converters (hereinafter, referred to as “DAC”) 32 and 34 and a two-input / one-output switch 36
, A headphone amplifier 38, and a control microcontroller (hereinafter, referred to as “controller”) that controls the operation of the entire CD player 10.
“Control microcomputer”) 60).

The RF amplifier 22 includes the pickup 16 and C
It is connected to the D-DSP 24, amplifies the signal output from the pickup 16, and outputs the amplified signal to the CD-DSP 24. Also, the CD-DSP 24 is composed of the servo circuit 20, the CD-
Connected to the ROM decoder 26 and the DAC 34,
CIRC for the signal input from the RF amplifier 22
(Cross Interleave Reed-Solomon Code) decoding, EFM
(Eight to Fourteen Modulation) Performs demodulation and other processing and outputs the result to the CD-ROM decoder 26 and the DAC 34.
ear Velocity) control.

The CD-ROM decoder 26 is an MP3
The decoder 30 is connected to the decoder 30, decodes data in a CD-ROM format indicated by a signal input from the CD-DSP 24, and outputs the data to the MP3 decoder 30. The RAM 28
Is used as a work area or the like at the time of decoding.

The MP3 decoder 30 is connected to the DAC 32, decodes MP3 format data indicated by the signal input from the CD-ROM decoder 26, and
Output to AC32. Further, DAC 32 and DAC 34
Are connected to one input terminal and the other input terminal of the changeover switch 36, respectively, and the output end of the changeover switch 36 is connected to the headphone amplifier 38. Therefore, by switching by the changeover switch 36, the MP3 format data decoded by the MP3 decoder 30 and converted to the analog signal by the DAC 32 and the MP3 format data output from the CD-DSP 24 and converted to the analog signal by the DAC 34 are supplied to the headphone amplifier 38. Signal
Is selectively input. Then, by connecting the headphones 70 to the headphone amplifier 38, the headphone amplifier 3
The analog signal amplified by 8 is reproduced by the headphones 70.

The servo circuit 20, the RF amplifier 22,
CD-DSP 24, CD-ROM decoder 26, MP3
A control microcomputer 60 is connected to each control input terminal of the decoder 30, the DAC 32, the DAC 34, and the changeover switch 36, and the operation of each unit is controlled by the control microcomputer 60.

Further, the control microcomputer 60 has a CD-ROM
An output end of the decoder 26 for outputting an interrupt signal INT,
The control microcomputer 60 is also connected to an output terminal for outputting header information of the MP3 decoder 30. The CD-ROM decoder 26 sends a CD-RO to the MP3 decoder 30 every time one sector of MP3 format data is transferred.
The interrupt signal INT output from the M decoder 26 can be input, and the MP3 decoder 30
Header information of each frame in three format data can be input. The sector of the MP3 format data and the header information of each frame will be described later.

A signal input to the headphone amplifier 38 via the DAC 32 is a signal corresponding to MP3 format data, and a signal input to the headphone amplifier 38 via the DAC 34 is a signal corresponding to data in the CD-DA format. According to the switching control of the changeover switch 36 by the control microcomputer 60, either the MP3 format data or the CD-DA format data is selectively reproduced. Specifically, the CD player 10 determines whether the CD set in the CD player 10 is a CD in which data is recorded in a CD-DA format or a CD in which data is recorded in a CD-ROM format. After detecting and switching the changeover switch 36 according to the detection result, the CD
Is performed.

On the other hand, the control microcomputer 60 includes an operation unit 40 having a power key, a reproduction key, a fast-forward key, a fast-return key, a stop key, a jog dial for inputting numbers, an enter key, and the like (not shown). A display unit 42 composed of a liquid crystal display on which display contents according to operation by the unit 40 and the like are displayed is connected. Further, the control microcomputer 60 is connected to a ROM 44 in which various control programs and parameters are stored in advance.

Here, the structure of audio data recorded on the CD 80 will be described with reference to FIG. In addition,
Here, a case where the data is MP3 format data will be described.

As shown in FIG. 2A, the data recorded on the CD 80 is composed of a plurality of files, and each file is composed of a set of a plurality of sectors each composed of 2048 bytes. Each sector is composed of a plurality of frames. Note that the number of frames included in one sector changes according to the size of each frame.

Each frame is composed of a header, side information, main data, and additional data, as shown in FIG.

The side information includes various information necessary for decoding the main data, such as window information and area designation.
The main data includes a scale factor and Huffman coded frequency components. The additional data is a part corresponding to the user data and is outside the MPEG standard.

Table 1 shows the structure of the header.

[0039]

[Table 1]

In the CD player 10 according to the present embodiment, various information in the header shown in Table 1 is stored in the MP3 decoder 3
0 is input to the control microcomputer 60. Note that the header configuration shown in Table 1 is widely known as the configuration of the MP3 frame header, and a detailed description thereof will be omitted.

Next, the operation of the CD player 10 according to the present embodiment will be described with reference to FIG. Here, a case where the data recorded on the CD 80 is MP3 format data will be described. That is, the changeover switch 36 controls the control microcomputer 60 so that the output terminal of the DAC 32 is connected to the input terminal of the headphone amplifier 38.
Has been switched by. In addition, here, only the operation related to the process of displaying the reproduction time of the MP3 format data recorded on the CD 80 (hereinafter, referred to as “reproduction time display process”), which is particularly related to the present invention, will be described. The description will be given on the assumption that the reproduction process of the MP3 format data is performed in parallel with the process. That is, FIG. 3 shows the MP recorded on the CD 80.
5 is a flowchart showing a flow of a reproduction time display processing program executed by the control microcomputer 60 of the CD player 10 when reproducing three format data, and this program is stored in a predetermined area of the ROM 44 in advance. Therefore, in the present embodiment, the ROM 44 corresponds to the recording medium of the present invention.

In step 100 of FIG. 3, the CD-ROM
Based on the interrupt signal INT input from the decoder 26, the absolute address of the first sector is assigned to a variable startPos as information indicating the first position of the file.

Step 10 to be executed subsequently
In 2, 104, 106 and 108, as an initial setting,
Variable bitr used to store the total bit rate
ate, a variable count used as a counter of the number of times of display when displaying the reproduction time, and a variable totalPo used to store the total number of bytes of data transferred from the CD-ROM decoder 26 to the MP3 decoder 30.
0 (zero) is substituted for each variable of average used for storing s and the average value of the bit rate.

In the next step 110, the control microcomputer 6
It is determined whether or not a predetermined time (100 mS in the present embodiment) has elapsed with reference to a timer (not shown) built in 0. If not, the process proceeds to step 126,
If it has elapsed, the process proceeds to step 112.

In step 112, based on the interrupt signal INT input from the CD-ROM decoder 26,
The absolute address of the sector currently being transferred is assigned to the variable nowPos as information indicating the current file position.

In the next step 114, the MP
The bit rate in the header information input from the 3 decoder 30 is extracted, added to the value of the variable bitrate, and stored in the variable bitrate.
In step 6, the variable count is incremented by 1, and in the next step 118, the value obtained by subtracting the value of the variable startPos from the value of the variable nowPos is substituted for the variable totalPos. By the arithmetic processing in step 118, the total number of bytes of the data transferred from the CD-ROM decoder 26 to the MP3 decoder 30 is derived.

In the next step 120, the variable avera
The value obtained by dividing the value of the variable bitrate by the value of the variable count is substituted for “ge”. By the processing of step 120, the CD-ROM decoder 26
The predetermined time (100 m in the present embodiment) in each frame of the data transferred from
A moving average of the bit rate for each S) is derived.

In the next step 122, the reproduction time TX is derived by the following equation (2).

TX = totalPos ÷ (average ÷ 8) (2) In the next step 124, the reproduction time TX derived in step 122 is displayed on the display unit 42, and in the next step 126, the reproduction of the file ends. It is determined whether or not the processing has been completed. If the processing has not been completed, the process returns to step 110, and when the processing has been completed, the main reproduction time display processing program ends.

The processing of step 114 corresponds to the bit rate obtaining means and the bit rate obtaining step of the present invention, the processing of step 118 corresponds to the data amount obtaining means and the data amount obtaining step of the present invention, and the processing of step 122 corresponds to the derivation of the present invention. The processing of step 124 corresponds to the means and the derivation step, and corresponds to the display means and the display step of the present invention, respectively.

As described above in detail, the CD player 10 according to the present embodiment obtains the bit rate of the data being reproduced at predetermined time intervals, and determines the data amount from the first frame to the frame being reproduced. Acquired, the playback time is derived based on the average value of the bit rate acquired every predetermined time and the data amount, and the derived playback time is displayed, so that a single bit rate is fixedly applied. The reproduction time can be accurately derived as compared with the case where the reproduction time is derived, and the reproduction time can be easily derived as compared with the case where the reproduction time is derived using the bit rates of all the frames. And as a result of this,
The reproduction time can be displayed easily and relatively accurately.

The CD player 1 according to the present embodiment
In the case of 0, since the average value of the bit rates acquired every predetermined time is applied as the bit rate used to derive the reproduction time, even if fast forward or fast reverse is performed during data reproduction, The reproduction time can be accurately derived.

In this embodiment, the case where the arithmetic mean value is applied as the average value of the bit rate in the present invention has been described. However, the present invention is not limited to this. May be applied. In this case, the same effect as in the present embodiment can be obtained.

In this embodiment, the case where MP3 is applied as the compression method in the present invention has been described. However, the present invention is not limited to this.
Any compression method in which the bit rate is recorded for each frame, such as MPEG-2 AAC and MPEG-4, can be applied. In this case, the same effect as in the present embodiment can be obtained.

In the present embodiment, the case where the CD 80 is applied as a recording medium for recording information to be processed by the present invention has been described. However, the present invention is not limited to this, and the present invention is not limited thereto. For example, CDV
(CD-Video), LD (LaserDisc), DVD (Digita
l All recording media on which information can be recorded, such as Video Discs or Digital Versatile Discs, are included.

Further, in the present embodiment, the case where the ROM 44 (semiconductor storage element) is applied as the recording medium of the present invention has been described. However, the present invention is not limited to this. -ROM,
A portable recording medium such as a magneto-optical disk or a magnetic tape, a fixed recording medium such as a hard disk, or an external storage device provided in a server computer or the like connected to a network may be applied.

[0057]

As described above in detail, according to the present invention, the bit rate of the data being reproduced is obtained at predetermined time intervals, and the data amount from the first frame to the frame being reproduced is obtained. Deriving a reproduction time based on the average value of the bit rate acquired every predetermined time and the data amount,
Since the derived playback time is displayed, the playback time can be accurately derived, as compared to the case where a single bit rate is fixedly applied to derive the playback time,
Compared to the case where the playback time is derived using the bit rates of all the frames, the playback time can be easily derived, and as a result, the display of the playback time can be performed easily and relatively accurately. Is obtained.

[Brief description of the drawings]

FIG. 1 is a block diagram showing an overall configuration of a CD player 10 according to an embodiment.

FIG. 2 is a schematic diagram showing an example of the structure of data recorded on a CD 80 to be reproduced by the CD player 10 according to the embodiment.

FIG. 3 is a flowchart showing a flow of a reproduction time display processing program executed in a control microcomputer 60 of the CD player 10 according to the embodiment.

[Explanation of symbols]

 Reference Signs List 10 CD player 30 MP3 decoder 42 Display unit 44 ROM (recording medium) 60 Control microcomputer

Claims (5)

[Claims] When a bit rate can be set for each frame and the data compressed by a compression method in which the bit rate is recorded for each frame is expanded and reproduced,
An information processing apparatus for displaying a reproduction time of the data, comprising: a bit rate obtaining means for obtaining a bit rate of data being reproduced at predetermined time intervals; and data for obtaining a data amount from a first frame to a frame being reproduced. Amount acquisition means, derivation means for deriving the reproduction time based on the average value of the bit rate acquired by the bit rate acquisition means and the data amount acquired by the data amount acquisition means, and the reproduction time derived by the derivation means An information processing apparatus comprising: a display unit that displays 2. The information processing apparatus according to claim 1, wherein the compression method is MP3. 3. The information processing apparatus according to claim 1, wherein the average value of the bit rates is a moving average value of the bit rates. 4. When expanding and reproducing data compressed by a compression method in which a bit rate can be set for each frame and said bit rate is recorded for each frame,
An information processing method for displaying a reproduction time of the data, comprising: a bit rate obtaining step of obtaining a bit rate of data being reproduced at predetermined time intervals; and data for obtaining an amount of data from a first frame to a frame being reproduced. An amount acquisition step, a derivation step of deriving the reproduction time based on the average value of the bit rate acquired by the bit rate acquisition step and the data amount acquired by the data amount acquisition step, and a reproduction time derived by the derivation step A display step of displaying: and an information processing method comprising: 5. When expanding and reproducing data compressed by a compression method in which a bit rate can be set for each frame and said bit rate is recorded for each frame,
A computer readable recording medium having recorded thereon a program for displaying a reproduction time of the data, comprising: a bit rate obtaining step of obtaining a bit rate of data being reproduced at predetermined time intervals; and A data amount obtaining step of obtaining the data amount of, a deriving step of deriving the reproduction time based on an average value of the bit rate obtained by the bit rate obtaining step and the data amount obtained by the data amount obtaining step, And a display step of displaying the reproduction time derived in the derivation step.