JP2007096404A - Video reproducing apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To synchronize the output timing of a digital video signal with the output timing of an analog video signal. <P>SOLUTION: The video reproducing apparatus includes: a read section for reading a digital video image and synchronization information from a recording medium for recording digital video information including the synchronization information; a demodulation section for demodulating the digital video information and the synchronization information read by the read section; a digital video output section for outputting a digital video signal on the basis of the digital video information and the synchronization information received through one transmission line from the demodulation section; an analog video output section for converting the digital video information received through one transmission line from the demodulation section into an analog video signal and providing an output thereof; and a control section that controls the output timing of the analog video output section on the basis of the synchronization information read from the read section to synchronize an output of the digital video signal from the digital video output section with an output of the analog video signal from the analog video output section. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

The present invention relates to a video reproducing apparatus that reproduces and outputs video from a recording medium such as an optical disk on which digital video information including synchronization information is recorded.

In a video playback apparatus that plays back video from a recording medium such as an optical disk on which digital video information including synchronization information is recorded, and outputs the video data and video data to be displayed in the digital video signal for one scanning line. There is an apparatus that transmits as a digital video signal including synchronous data SAV (Start of Active Video) indicating start and synchronous data EAV (End of Active Video) indicating the end of active video data (see Patent Document 1).

FIG. 3 is a block diagram showing a configuration of an example of a conventional video reproduction apparatus. The disc reading unit 1 reads digital video information including synchronization information recorded on a DVD (Digital Versatile Disc) or the like. An MPEG (Moving Picture Experts Group) decoder 2 demodulates the digital video information read by the disk reading unit 1 and outputs the demodulated digital video signal to the digital video signal output unit 4 and the analog video signal output unit 5. The digital video signal output unit 4 outputs the digital video signal to the output terminal 4a. The analog video signal output unit 5 converts the digital video signal into an analog video signal and outputs it to the output terminal 5a.
Here, the digital video signal output unit 4 and the analog video signal output unit 5 may have different synchronization timings required for displaying a normal video on the display device.

Japanese Patent Laid-Open No. 11-259056

Since the apparatus of Patent Document 1 does not output a plurality of video signals, it does not have a function of simultaneously outputting a digital video signal and an analog video signal.

In the conventional video reproduction apparatus, when the synchronization timings required for displaying the digital video signal output from the digital video signal output unit 4 and the analog video signal output from the analog video signal output unit 5 are different, the MPEG decoder 2 and the digital video signal output unit 4 and the analog video signal output unit 5 are required to have a plurality of transmission lines for inputting the digital video signal at different synchronization timings.

In other words, two systems of digital video signal output circuits including synchronization information at different timings are provided in the MPEG decoder 2 and transmitted between the MPEG decoder 2, the digital video signal output unit 4 and the analog video signal output unit 5, respectively. The digital video signals corresponding to the different synchronization timings are simultaneously output from the MPEG decoder 2 by connecting with the lines, and the digital video signals having the synchronization timings synchronized from the digital video signal output unit 4 and the analog video signal output unit 5 Signals and analog video signals can be output simultaneously.

Generally, eight digital video signal transmission lines are required. In the video reproduction apparatus shown in FIG. 3, eight transmission lines from the MPEG decoder 2 to the digital video signal output unit 4 are provided. 8 transmission lines to the analog video signal output unit 5, a total of 16 transmission lines are required. Some video playback devices for playing back higher-definition video have 10 transmission lines for transferring digital video signals. In that case, a total of 20 transmission lines are required. To do. The transfer rate of digital video signals is as high as 10 MHz or higher.

In the configuration for outputting a plurality of video signals, the number of transmission lines is increased, which is complicated. Since the transfer speed of digital video signals is as fast as 10 MHz or more, increasing the number of video signal transmission lines increases the board area to be mounted, which may affect the surrounding electrical circuits, There was a problem of increasing unnecessary radiation of electromagnetic waves to the outside of the apparatus.

An object of the present invention is to enable a video playback apparatus to simultaneously output video information read from a recording medium as a digital video signal and an analog video signal at the same synchronization timing with a minimum number of transmission lines. To provide an apparatus.

According to a first aspect of the present invention, there is provided a video reproducing apparatus including a reading unit that reads digital video and synchronization information from a recording medium on which digital video information including synchronization information is recorded, and the digital video information and synchronization read by the reading unit. A demodulator that demodulates information; a digital video output unit that outputs a digital video signal based on the digital video information and synchronization information demodulated by the demodulator input from a single transmission line from the demodulator; and the demodulator An analog video output unit that converts the digital video information demodulated by the demodulator input from a single transmission line into an analog video signal and outputs the analog video signal, and the analog video based on the synchronization information read from the readout unit Controls the output timing of the analog video signal output from the output unit, and outputs the data from the digital video output unit. In which a control unit for synchronizing with the output of the digital video signal output of the analog video signal from the analog video output unit.

According to the video reproduction apparatus of the present invention, digital video information read from a recording medium can be simultaneously output as a digital video signal and an analog video signal at the same synchronization timing with the minimum number of transmission lines.

FIG. 1 is a block diagram showing a configuration of an embodiment of a video reproduction apparatus of the present invention.
The disc reading unit 1 is loaded with an optical disc such as a DVD on which a video signal such as a movie is recorded, and reads a digital video signal from the loaded optical disc. The MPEG decoder 2 separates the main picture bit stream from the digital video signal read by the disk reading unit 1, MPEG decodes it, and outputs it as a digital video signal.
The synchronization signal output unit 3 detects a synchronization signal included in the digital video signal decoded by the MPEG decoder 12, and generates and outputs a horizontal synchronization signal HS and a vertical synchronization signal VS.

The digital video signal decoded by the MPEG decoder 2 is input to the digital video signal output unit 4 and the analog video signal output unit 5.
The digital video signal output unit 4 outputs the digital video signal to the output terminal 4a at the synchronization timing based on the synchronization code.
The analog video signal output unit 5 converts the digital video signal into an analog video signal and outputs it to the output terminal 5a at a synchronization timing based on the horizontal synchronization signal HS and the vertical synchronization signal VS input from the synchronization signal output unit 3.

The control unit 6 controls the disk reading unit 1, the MPEG decoder 2, the digital video signal output unit 3, and the analog video signal output unit 4.
The operation unit 7 includes operation buttons for performing operations such as start and stop of reproduction of the optical disc, and inputs an operation signal to the control unit 6. The operation unit 7 can also be implemented as a configuration in which an operation signal is transferred by infrared rays and input to the control unit 6 using a remote controller having operation buttons.
The display unit 8 displays a display signal that is input from the control unit 6 and indicates an operation state of the video reproduction device, or an information signal read by the disc reading unit 1.

FIG. 2 is a diagram showing an example of a signal in the video reproduction apparatus of the present invention. In FIG. 2, (a) is a vertical synchronizing signal VS, (b) is a horizontal synchronizing signal HS, and (c) is a digital video signal.
The digital video signal output from the MPEG decoder 2 is a 4-byte synchronization signal (hereinafter referred to as synchronization) indicating the video data to be displayed and the start and end of the video data in the digital video signal for one scanning line. SAV, EAV) are included. Here, an example of an interlace signal (interlace scanning method) using an NTSC signal is shown.

The synchronization code 4 bytes is composed of a fixed value 3 bytes and a variable value 1 byte, and indicates the start and end of the video data, that is, the start and end of the video display range.
The vertical sync signal VS and horizontal sync signal HS indicate the vertical and horizontal display positions of the video signal to be displayed. In analog video output, a display device such as a television broadcast receiver is required to display video. Indicates the position and information of the synchronization signal.

In this embodiment, the digital video signal output unit 4 inputs a digital video signal including a synchronization code from the MPEG decoder 2 and outputs the digital video signal at a timing based on the synchronization code. The analog video signal output unit 5 inputs the digital video signal output from the MPEG decoder 2 and the horizontal synchronization signal HS and the vertical synchronization signal VS output from the synchronization signal output unit 3, and the horizontal synchronization signal HS and An analog video signal is output at a synchronization timing based on the vertical synchronization signal VS.

As described above, according to the video reproduction apparatus of the present embodiment, the digital video signal can be transferred from the MPEG decoder 2 to the digital video output unit 4 and the analog video output unit 5 through one transfer path. Since the timing is adjusted, a plurality of video signal outputs, that is, an analog video signal output and a digital video signal output can be performed simultaneously.

It is a block diagram which shows the structure of one Example of the video reproduction apparatus of this invention. It is a figure which shows the example of the digital video signal in the video reproduction apparatus of this invention. It is a block diagram which shows the structure of an example of the conventional video reproduction apparatus.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Disc reading part 2 MPEG decoder 3 Synchronization signal output part 4 Digital video signal output part 5 Analog video signal output part 4a, 5a Output terminal 6 Control part 7 Operation part 8 Display part

Claims (1)

A reading unit that reads digital video and synchronization information from a recording medium on which digital video information including synchronization information is recorded, a demodulation unit that demodulates the digital video information and synchronization information read by the reading unit, and one from the demodulation unit A digital video output unit that outputs a digital video signal based on the digital video information and synchronization information demodulated by the demodulator input by the transmission line, and the demodulator input by one transmission line from the demodulator An analog video output unit that converts the digital video information demodulated into an analog video signal and outputs the analog video signal, and controls the output timing of the analog video signal output by the analog video output unit based on the synchronization information read from the reading unit. The digital video signal output from the digital video output unit and the analog video Video reproducing apparatus characterized by comprising a control unit for synchronizing the output of the analog video signal from the force unit.

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