KR20030060230A - Video Processing Apparatus for DTV - Google Patents

Abstract

PURPOSE: A video processor of a digital TV is provided to share a PIP format converter and a VCR recording format converter to reduce the amount of utilization hardware. CONSTITUTION: A storage unit(10) stores an input image. A main format converter(11) converts a format of the stored image. A PIP(picture in picture) multiplexer(12) inserts an output image of a sub format converter(14) into the output image of the main format converter. A VCR(video cassette recorder) multiplexer(13) selectively provides the output image of the main format converter, output image of the PIP multiplexer and video signal stored in the storage unit to the sub format converter. The sub format converter converts the format of the output of the VCR multiplexer into a format suitable for a PIP screen or VCR screen, and then selectively provides the output of the VCR multiplexer to the PIP multiplexer of VCR screen. A clock and synchronous signal generator(15) supplies a PIP clock and synchronous signal to the sub format converter and provides a clock and synchronous signal for VCR.

Description

Video Processing Apparatus for DTV

The present invention relates to a digital TV, and more particularly, to an image processing apparatus of a digital TV.

Recently, with the introduction of digital TV, it is possible to watch high quality video about 5 ~ 6 times compared to the existing analog TV, and the sound quality can also be heard at the CD level.

In addition, the product range is diversified, so that the set-top box has only a function of decoding and outputting an MPEG image without a display function, a digital TV having both decoding and display function of an MPEG image, and no decoding function of an MPEG image, Products such as HDTV monitors that only display in resolution are now becoming major products as they form their respective markets.

In addition, the functions have been diversified, so it is easy to obtain not only video or audio information but also various additional information through data broadcasting.The PIP function, which was applied only to a very expensive product family in the conventional analog TV, is a basic function in the digital TV. Analog TV and analog TV recording devices are also available for the company.

1 is a view illustrating a conventional image processing apparatus of a digital TV, including a storage unit 1 for storing an input image image, a main screen format converter 2 to read at a necessary time point, and a PIP screen format converter 3 ), A VCR format converter (4) and a PIP mux (5).

The digital TV image processing apparatus is being applied to various products at the same time. The set-top box decodes MPEG images and outputs them in the analog video format of RGB or YpbPr, which is commonly used, or DVI (Digital visualInterface). It also outputs the digital video format of S-Video and CVBS (Composite Video Baseband Signal) signal for the existing analog TV or analog TV recording device.

Therefore, the VCR format converter 4 plays a very important role, but most of the functions of the PIP format converter 3 are not required.

Digital TV is responsible for displaying the decoded video as well as the MPEG decoding function of the set-top box.

In this case, an analog video signal as well as a digital video display must be displayed.

In addition, there is a great demand to simultaneously view both analog and digital video signals. Therefore, compared to analog signals, it is necessary to be able to send better quality video to more channels, and to view multiple channels of video simultaneously. Because PIP, POP, and multi-PIP functions are required, the format converter for PIP plays a very important role.

Therefore, if the VCR recording device is separated separately as in the conventional digital TV, it can perform better function, but its importance is inferior to that of the PIP format converter, and the function is duplicated when used with a set-top box. There is a problem that the hardware usage increases.

Accordingly, an object of the present invention is to devise in view of the above-mentioned problems of the prior art, by using a PIP format conversion unit and a VCR recording format conversion unit to reduce the amount of hardware used digitally available in various digital TV products at the same time It is to provide a TV image processing apparatus.

1 is a view showing a conventional digital TV image processing apparatus

2 is a view showing an image processing apparatus of a digital TV according to the present invention.

3 is a block diagram and display form of a PIP screen of a digital TV image processing apparatus according to the present invention;

4 is a block diagram and display form of the VCR screen of the digital TV image processing apparatus according to the present invention.

* Description of the symbols for the main parts of the drawings *

10: storage unit 11: main screen format conversion unit

12: PIP mux 13: VCR mux

14: sub picture format conversion unit

15: clock and synchronization signal generator

According to a feature of the present invention for achieving the above object, the storage unit for storing the input image, the main screen format conversion unit for converting the format to display the stored image, and the output image of the main screen format conversion unit A PIP mux unit for inserting and outputting an output image of the sub-screen format conversion unit and an output image of the main screen format conversion unit or an output image of the PIP mux unit or an image signal stored in the storage unit for selectively providing the sub-screen format conversion unit A sub picture format conversion unit for selectively converting a VCR mux unit, and outputting the output of the VCR mux unit to a PIP screen or a VCR screen, and optionally providing the PCR mux unit or a VCR screen to the sub picture format conversion unit; Including a clock and synchronization signal generator for providing a clock and a synchronization signal for the PIP and a clock and a synchronization signal for the VCR screen. It is.

Preferably, the clock and sync signal generator applies a control signal to the sub-picture format converter to provide an adjustment signal to make a PIP screen or a VCR output screen.

Hereinafter, a configuration and an operation according to an exemplary embodiment of the present invention will be described with reference to the accompanying drawings.

2 is a view showing an image processing apparatus of a digital TV according to the present invention.

Referring to FIG. 2, a storage unit 10 for storing an image, a main screen format conversion unit 11 for performing a format conversion on the stored image to match the display device, and the main screen format conversion unit 11 The PIP mux unit 12 for inserting and outputting an output image, an output image of the main picture format conversion unit 11, an output image of the PIP mux unit 12, and an image signal provided from the storage unit 10 are selectively selected. After receiving the output of the VCR mux section 13 and the VCR mux section 13 provided to the sub-screen format converting section 14, and converting the screen to fit the PIP screen or the VCR screen, PIP as necessary. The sub picture format converting section 14 provided on the MUX section 12 and the VCR screen and the sub picture format converting section 14 are supplied with the PIP clock and the synchronization signal according to the usage form, or are synchronized with the VCR screen clock. It is composed of a clock and a synchronization signal generator 15 for providing a signal.

The main picture format converting unit 11 converts an analog broadcast signal such as NTSC or PAL, a PC signal such as VGA or XGA, and MPEG images of various sizes used in a digital TV into a resolution of a display device. It performs the role of converting.

Then, appropriate filtering is performed according to the resolution of the input image and the resolution of the output image, and if necessary, conversion of the interlaced scan type image input into a sequential scan type is performed.

The main screen format converting unit 11 operates separately from the sub screen format converting unit 14 when a main screen display clock and a synchronization signal are applied.

The PIP mux unit 12 performs a function of properly combining the output image of the main screen format converter 11 and the output image of the sub-screen format converter 14. That is, when the user wants to watch only the main screen, the main screen may be output regardless of the presence or absence of the sub-screen image.

When the user requests a PIP screen or a split-screen (dual screen) or the like, the main screen and the sub-screen each constitute their own screens with appropriate clocks and synchronization signals, and the PIP mux unit 12 displays each screen. It selects a valid part and prints it out.

In general, an image that has passed through the main picture format converter 11 may undergo various image processing processes until the final output. For example, the noise reduction circuit eliminates noise components present in the image, and the sharpening enhancement circuit reinforces the reduction of the video signal generated when the noise is removed.

In addition, the brightness, contrast and color of the image may be adjusted.

In addition, gamma correction may be performed according to characteristics of the display device, and an OSD screen for informing a user selection or channel information may overlap.

When outputting the main screen to the VCR screen, it is necessary to output the screen that the user prefers to the VCR screen among the image processing screens in various forms, and for this purpose, the VCR mux unit 13 is provided.

The VCR mux unit 13 may receive an output of the main screen format converter 11 or an image output subjected to post-processing such as noise reduction or brightness adjustment as an input, and provide the input to the sub-screen format converter 14. do.

In addition, the data stored in the storage unit 10 may be directly input to the sub-screen format converter 14.

The sub picture format conversion unit 14 provides an image constituting a PIP screen or a VCR screen by using a clock and a synchronization signal provided by the clock and synchronization signal providing unit 15.

In the case of providing a PIP screen, the video data provided by the VCR mux unit 13 is configured as a PIP screen in consideration of the synchronization signal of the main screen format converter 11. At this time, if necessary, the size of the PIP screen may be adjusted to configure various screens such as a split screen and a POP.

In the case of configuring a VCR screen, the video data provided from the VCR mux unit 13 converts the image data into the size of an existing analog broadcast signal and outputs the same.

Conventional VCR output or analog broadcast signal has a 4: 3 horizontal / vertical aspect ratio, but digital TVs have various aspect ratios, so the sub-screen format converter 14 displays the user's desired form. If the input has an aspect ratio of 16: 9, the display mode compresses the entire screen horizontally, and after cutting the left part and the right part of the entire screen into 4: 3 screens, It plays a role of implementing various display modes such as the display mode or the 16: 9 screen, which is made smaller, to display the entire 16: 9 screen without using the upper and lower portions of the 4: 3 screen.

The clock and sync signal generator 15 applies an appropriate control signal to the sub-picture format converter to provide an adjustment signal to generate a PIP screen or a VCR output screen as necessary.

That is, it receives the clock for the main screen display, the clock for the memory access, and the clocks for the VCR screen display, and provides the sub-screen format converter 14 with a necessary clock suitable for the display mode.

For example, it will be described through Table 1 below.

Table 1 1920x1080 interlaced main screen resolution

Main screen format converter Sub picture format conversion unit (PIP mode) Sub picture format converter (VCR mode) Vertical sync signal 30 Hz 30 Hz 30 Hz Horizontal sync signal 33.75KHz 33.75KHz 15.7KHz Display clock 74.25 MHz 74.25 MHz 13.5 MHz Input clock 108 MHz 108 MHz 74.25 MHz Output clock 74.25 MHz 74.25 MHz 13.5 MHz

As shown in Table 1, when the display resolution of the main screen has a 1920x1080 interlaced scan format, the main screen format converter needs a display clock of 74.25 MHz. In addition, it is assumed that 108 MHz is used to read image data in the memory.

If the sub-screen format converter 14 operates to provide a PIP screen, the sub-screen format converter 14 should be provided with an image processing clock of 74.25 MHz, and the PIP screen is configured at a desired position of the main screen. The PIP screen synchronization signal should be provided to the sub picture format converting unit 14 so as to enable it.

On the other hand, when the display resolution of the main screen has a 1920x1080 interlaced scan form as shown in Table 1 above, and the sub-screen format converter 14 operates to provide a VCR screen, the sub-screen format converter 14 is subject to VCR processing. A proper 13.5MHz image processing clock must be applied for proper operation.

[Table 2 1280x720 progressive scan main screen resolution]

Main screen format converter Sub picture format conversion unit (PIP mode) Sub picture format converter (VCR mode) Vertical sync signal 60 Hz 60 Hz 30 Hz Horizontal sync signal 45KHz 45KHz 15.7KHz Display clock 74.25 MHz 74.25 MHz 13.5 MHz Input clock 108 MHz 108 MHz 74.25 MHz Output clock 74.25 MHz 74.25 MHz 13.5 MHz

The horizontal synchronization signal of the sub picture does not need to match the horizontal synchronization signal of the main picture, but the vertical synchronization signal should be adjusted to have the same period as the vertical synchronization signal of the main picture.

For reference, Tables 2 to 4 show examples of clock and sync signals provided by the clock and sync signal generator 15 when the main screen has various resolutions.

Table 3 720x480 progressive scan main screen resolution

Main screen format converter Sub picture format conversion unit (PIP mode) Sub picture format converter (VCR mode) Vertical sync signal 60 Hz 60 Hz 30 Hz Horizontal sync signal 31.5KHz 31.5KHz 15.7KHz Display clock 27 MHz 27 MHz 13.5 MHz Input clock 108 MHz 108 MHz 27 MHz Output clock 27 MHz 27 MHz 13.5 MHz

Table 4 720x480 interlaced main screen resolution

Main screen format converter Sub picture format conversion unit (PIP mode) Sub picture format converter (VCR mode) Vertical sync signal 30 Hz 30 Hz 30 Hz Horizontal sync signal 15.7KHz 15.7KHz 15.7KHz Display clock 13.5 MHz 13.5 MHz 13.5 MHz Input clock 108 MHz 108 MHz 13.5 MHz Output clock 13.5 MHz 13.5 MHz 13.5 MHz

3 is a block diagram and a display form of a PIP screen of the digital TV image processing apparatus according to the present invention.

Referring to FIG. 3, it can be seen that the clock and sync signal generator and the two muxes are respectively adjusted so that the VCR screen providing unit disappears and the PIP screen is configured and operated.

4 is a block diagram and a display form of a VCR screen of the digital TV image processing apparatus according to the present invention.

Referring to FIG. 4, it can be seen that the clock and sync signal generator and the two muxes are respectively adjusted so that the PIP screen providing unit disappears and the VCR screen is configured and operated.

As described above, the present invention provides an appropriate clock and synchronization signal in the clock and synchronization signal generator so that a single format converter is used as a format converter for a PIP and a format converter for a VCR output. There is an advantage that can be greatly reduced.

In addition, VCR output is essential in set-top boxes, and PIP function is a basic function in all-in-one digital TVs, which can effectively cope with various applications. There is an advantage.

Those skilled in the art will appreciate that various changes and modifications can be made without departing from the spirit of the present invention.

Therefore, the technical scope of the present invention should not be limited to the contents described in the examples, but should be defined by the claims.

Claims (2)

A storage unit which stores an input image; A main screen format conversion unit for converting the stored image to be displayed in a format; A PIP mux unit for inserting and outputting an output image of the sub-screen format converter into the output image of the main screen format converter; A VCR mux for selectively providing an output image of the main screen format converter, an output video of the PIP mux, or an image signal stored in the storage; A sub picture format converting unit for converting the output of the VCR mux unit into a PIP screen or a VCR screen and selectively providing the screen to the PIP mux unit or the VCR screen; And a clock and a synchronization signal generator for providing a PIP clock and a synchronization signal to the sub-screen format converter and providing a clock and a synchronization signal for a VCR screen. The method of claim 1, And the clock and synchronization signal generator is configured to apply a control signal to the sub-picture format converter to provide an adjustment signal to generate a PIP screen or a VCR output screen.