KR0160854B1 - Method of screen processing for video cdp - Google Patents

Abstract

The present invention relates to video CDP.

Conventional screen processing method of VCDP reads up to 512 KBytes from 4 seconds and 34 frames after power on and stores them in external RAM and performs the corresponding operation according to the user's selection key input. There was this.

Accordingly, the present invention is intended to improve the above-mentioned problems of the prior art, so that a list designated by each offset of the current list belongs to a fast access to a target point without using a large amount of RAM in the VCDP. The number of sectors with the largest number of duplicated sectors is read in advance so that some of the maximum number of PSD VCD files are stored in RAM instead of the maximum to induce fast access.

Description

Video processing method of video CD

1 is a flowchart of an operation of a conventional video CDP.

(A) to (c) of FIG. 2 are a list combination display diagram of a conventional video CDP file.

3 is an operation screen display diagram of a video CDP according to FIG.

4 is a block diagram of a CDP MPEG unit for implementing the present invention.

5 is a flowchart of a screen processing procedure of a video CDP according to the present invention.

* Explanation of symbols for main parts of the drawings

10: CD ROM decoder section 11, 21: first and second RAM

20: MPEG decoder unit 30: MPEG microcomputer

40: external ram

The present invention relates to a method of accessing a video CDP (Video Compact Disk Player (hereinafter referred to as VCDP) menu) using a menu method, and in particular, playback by a menu method without using a large amount of RAM in a microcomputer of the VCDP. The present invention relates to a screen processing method of a VCDP that enables fast access using low-capacity RAM.

In the conventional VCDP version (Ver) 2.0 standard, a PSD Play Sequence Descriptor VCD (VCD) file that defines the control order for still and moving pictures must exist after 4 seconds and 34 frames.

That is, as shown in (a) and (b) of FIG. 2, the PSD VCD file is composed of a combination of the two lists.

First, (a) is a selection list, and (b) is a play list. The two lists are randomly stored in the external RAM (c) from 4 seconds 34 frames up to 512K bytes. .

The play list and the selection list will be described in detail with reference to FIGS. 1 and 3 as follows.

First, FIG. 1 is a flowchart of the operation of the conventional VCDP. As shown in FIG. 1, when the power is supplied to the system, the play control is controlled by the PSD information, so that the maximum is 512 bytes from 4 seconds 34 frames (PSD, VCD file). Is stored in the external RAM (c).

After the play-on, the first list is interpreted by the microcomputer (not shown in the drawing), the RAM (c) is searched and accessed to show the place where the image is stored, and the user waits for a key input.

That is, as an example, as shown in FIG. 2, the first screen 1 displays the current playlist ( movie, karaoke, Search for the user's keystrokes.

Here, the key input searches for a key input such as prev, next, return, default, timeout, or number key (1, 2, 3, ...) input when the current list is the selected list.

If the user says' Movie 'as shown in the second screen (2) below, Benhur, Show a long bridge, etc.) and wait for user input.

If user ' Benhur 'will start the movie, from which time it will be controlled by keystrokes by the playlist.

Here, the keystroke jumps to the corresponding offset to play the playlist and retrieves the user's keystroke again, that is, if the current list is a play input, the keystrokes of prev, next, and return are retrieved. If so, perform the action.

As such, when a specific offset by the user's key input is determined, the user jumps to the list corresponding to the offset, reads the list into the MICOM internal RAM (not shown), and plays the corresponding play item, and waits for the user's key input.

However, the screen processing method of the conventional VCDP reads up to 512 Kbytes from 4 seconds 34 frames after power on and stores them in the external RAM, and performs the corresponding operation according to the user's selection key input. There was a problem to use.

Accordingly, the present invention is intended to improve the above-mentioned problems of the prior art, so that a list designated by each offset of the current list belongs to a fast access to a target point without using a large amount of RAM in the VCDP. It is an object of the present invention to provide a screen processing method of a VCDP that reads a sector with the most overlapping sectors in advance and partially stores the maximum number of PSD VCD files in RAM to induce fast access.

The present invention for achieving the above object comprises the first step of storing the PSD information in the initial position of the RAM after the user turns on the power and the next most probable order in sector order with the highest probability; A second step of retrieving whether there is a servo pause command after playing the play item of the first list as the play is turned on after storing the PSD information; A third step of transmitting an address of a sector having a high probability when there is a servo pause command, storing each sector in RAM, and searching whether a current list is present in the RAM; If the current list does not exist in the RAM, the current list sector and the next sector are stored in the RAM, then the play item of the current list is played. A fourth process of returning and repeating; When the current list exists in the RAM, a fifth process of regenerating the play item of the current list, calculating a sector address having a high probability from the current list, and returning to the pause search process is repeated.

Here, the calculation of the highest probability sector address and the next highest probability sector address in the first process is characterized by the following conditions.

00:04:34 + (offset × 8 ÷ 7FF)

In this condition, 00:04:34 is the sector of the first PSD information.

In addition, in the second process, as the play is turned on, converting the play item number of the first list into time information and sending it to the DCP; As a result of starting the playback of the MPEG stream input from the CDP, the present invention will be described in detail with reference to the accompanying drawings.

FIG. 4 is a block diagram of the CDP MPEG unit according to the present invention. As shown in FIG. 4, the data of the compressed CD ROM scanned and inputted by the CDP under the control of the servo is decoded and stored in the first data RAM 11. And the CD ROM decoder 10 for reading and outputting the stored data and the data decoded and inputted by the CD ROM decoder 10 into MPEG data, stored in the second data RAM 21, and decompressed. An MPEG decoder 20 for outputting, an MPEG microcomputer 30 for controlling the CD ROM decoder 10 and the MPEG decoder 20 by interfacing the CDP with a control signal, and the CD ROM decoder 10 The decoded data outputted from the < RTI ID = 0.0 > 1) < / RTI >

When described in detail with reference to Figure 4 and Figure 5 the effect of the present invention configured as described above.

First, as shown in FIG. 4, the present invention decodes compressed CDP data read by an optical pickup device (not shown) in the CD ROM decoder unit 10 and stores it in the first RAM 11. Let's do it.

The CD data decoded as described above is transmitted to the MPEG decoder unit 20 according to the control signal of the MPEG microcomputer 30.

The MPEG decoder 20 receiving the CD data expands and outputs the digital data under the control of the MPEG microcomputer 30 and stores the same in the second RAM 21.

In addition, the control data of the MPEG microcomputer 30 is stored in the external RAM 40 in the order of sectors of the screen most selected by the user, thereby quickly finding the target screen selected by the user.

The sector retrieval method most frequently used by the user in the external RAM 40 is as follows.

The target screen on which the user selects a number may exist at any position on the disk.

Therefore, in order for the optical pickup apparatus to access the position corresponding to the target screen, the time information must be calculated with the play item number to be reproduced in the current list.

However, the current list changes frequently as the user enters a key.

Therefore, in order to quickly find the target screen while reducing the capacity of the existing external memory, the instantaneous instantaneous PSD information is read and the number of readings is reduced, so that only a small amount of memory can quickly find the target screen.

In other words, when reading the current PSD information, when the current list is the selection list, the play item is often a still image. Therefore, after reading the first screen, the servo should be paused until the user key is input. To do this, the PSD information is read using the paused time.

In addition, even if the current list is a play list, if the play item is a still image, this time period is used since the servo pause state exists.

In order to reduce the number of times of reading the instant PSD information, the address of the sector having the highest probability must be calculated and the sectors are stored in the external RAM 40 in the order of the highest probability.

For example, the current list is a selection list and three selection offsets ( movie, Come on, Football), then displays the screen on the screen as shown in the first screen 1 of FIG. 1 and searches for a user's key input as follows.

Prior list offset

Next list offset

Return list offset

Timeout list offset

Selection 1 offset (movie)

Selection 2 offset (karaoke)

Selection 3 offset (soccer)

In other words, the user selects any of the above eight offsets. At this time, if any one of the offsets is selected, the list indicated by these nine offsets is externally displayed to immediately indicate the position (time information) of the disk on which the screen is located. The sectors indicated by these offsets may be in the same sectors, but calculated by the following equation.

00:04:34 + (offset × 8 ÷ 7FF)

Therefore, substituting the eight offsets into the equation gives the following values.

Prev = 00:04:35

Next = 00:04:35

Return = 00:04:35

Default = 00:04:35

Timeout = 00:04:36

Selection 1 = 00:04:35

Selection 2 = 00:04:37

Selection 3 = 00:04:36

The most overlapping sectors as calculated above are 00:04:35, so when these sectors are read into the external RAM 40 using the servo stop time, they include prev, next, default, and selection 1. When any of the four user keys is entered, time information can be calculated from the position of the disk on the screen immediately.

That is, read the most available sectors.

In addition, the result of the calculation shows that the next most available sector is 00:04:36, so this sector address can be read in advance within the limits allowed by the external RAM 40.

Thus the required external RAM 40 is two sectors, or 4K bytes.

The remaining offset is then read when the corresponding key is entered by the user.

5 is a flowchart of a screen processing process of the VCDP according to the present invention. As shown in FIG. 5, when the user turns on the power, the entire PSD VCD file is not stored in the external RAM 40 at 00:04:34 and 00:04. The 35 sectors are stored in the external RAM 40.

Here, the initial PSD information uses sectors 00:04:34.

Then, each offset value of the first list is substituted into the above equation to calculate the highest probability sector address and the next highest probability sector address.

If the next play comes, the play item number of the first list is converted into new information, transmitted to the CDP, and playback of the MPEG stream input from the CDP is started.

At this time, if there is a servo pause command, the highest probability sector address and the next highest probability sector address are sent to the CDP and stored in the PSD area of the external RAM 40 of 8 K bytes.

If the current list is changed by the user key, it checks whether the sector containing this list exists in the 8K byte external RAM 40, and if it does not exist, reads the sector containing the current list and reads the 8KB external RAM (40). Overwrites the 4K byte area

In other words, the sector containing the current list and the next sector are read, so that the sector is two sectors, so a 4K byte area is required.

If the current list exists in the external RAM 40, the play item number of this list is converted into time information, transmitted to the CDP, and the MPEG stream inputted from the CDP is reproduced.

Substituting each offset value of the list into the above equation calculates the highest probability sector address and the next highest probability sector address, and returns to the process of searching for the servo pause state.

As described above, in order to realize fast access to a target point without using a large amount of RAM in the microcomputer of the VCDP, the present invention identifies a sector having the highest number of sectors to which the list belonging to each offset of the current list belongs. It reads in advance and saves some of the maximum PSD VCD file in RAM, instead of storing it in full, to induce quick access, and it has a great effect that can be played by menu method using RAM of low capacity (4K byte: PSD only). have.

Claims (3)

The first process of storing the PSD information in the initial position of the RAM after the user turns on the RAM and the most probable sectors in the next sequential address, and the first list of the first list as the play is turned on after storing the PSD information. A second step of searching for a servo pause command after playing the play item, and transmitting the address of a sector having a high probability if the servo pause command is present, storing each sector in RAM, and then present a list. A third step of searching for a change and whether it exists in the RAM; and if the current list does not exist in the RAM, storing the current list sector and the next sector in the RAM, and then playing the current play list item. A fourth step of repeating a process of calculating a sector address having a high probability in the list of s and returning to the pause search process, and the current list exists in the RAM In this case, the video processing of the video CD is performed by playing a play item of the current list, and calculating a sector address having a high probability from the current list and returning it to the pause search process. Way. The method according to claim 1, wherein the highest probability sector address and the next highest probability sector address satisfy the following conditions in the first process. 00:04:34 + (offset × 8 ÷ 7FF) In this condition, 00:04:34 is the sector of the first PSD information. 2. The method of claim 1, wherein the second process comprises converting the play item number of the first list into time information and sending it to the DCP as the play is turned on, and starting playback of the MPEG stream input from the CDP. Screen processing method of a video CD (CDP) characterized in that made.