JP2005341233A - Video signal receiving device and video signal receiving method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a video signal receiving device and a video signal receiving method which convert a received RGB signal to a format which can display in the highest image quality from among the video output formats established beforehand responding to the number of perpendicular lines, and is able to prevent deterioration of the vertical resolution. <P>SOLUTION: The device is provided with a receiving means 17 which selectively receives an RGB signal corresponding to VGA, SVGA, and XGA; a detection means 28 which detects kinds of the RGB signal received by the receiving means 17; and output means 18, 23 which converts and outputs the RGB signal corresponding to the VGA to 540p format, based on the detection result of the detection means 28, and converts and outputs the RGB signal, corresponding to the SVGA and XGA, into a 1080i format. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a video signal receiving apparatus and a video signal receiving method for selectively receiving a plurality of types of RGB signals having different numbers of vertical lines and converting them into video signals having a format compliant with a display device.

  As is well known, recent television receivers have a function of selectively receiving a plurality of types of RGB signals having different numbers of vertical lines, converting them into television format video signals, and displaying images. The ones that have been prepared have appeared.

  Specifically, RGB signals output from a PC (Personal Computer) in a plurality of computer graphics formats corresponding to VGA (Video Graphics Array), SVGA (Super Video Graphics Array), or XGA (eXtended Graphics Array). Is selectively received, converted into an interlace format compliant with CRT (Cathode Ray Tube) or the like, and displayed.

Japanese Patent Application Laid-Open No. 2004-228561 discloses a configuration for scale conversion for interlace conversion of a video signal output from a PC, a configuration for reducing flicker in an interlace conversion process, and the like. By the way, a technology for converting a video signal in a computer graphics format into a video signal in a television format and displaying the video is still under development, and there is still a lot of room for improvement in various respects. Is the current situation.
Japanese translation of PCT publication No. 2002-515988

  Therefore, the present invention has been made in consideration of the above circumstances, and in accordance with the number of vertical lines, the received RGB signal is displayed in a format that can display the highest quality among the preset video output formats. An object of the present invention is to provide a video signal receiving apparatus and a video signal receiving method capable of preventing deterioration of vertical resolution by performing conversion.

  A video signal receiving apparatus according to the present invention includes a receiving means for selectively receiving a plurality of types of RGB signals having different numbers of vertical lines, a detecting means for detecting horizontal and vertical frequencies of the RGB signals received by the receiving means, and a detection Conversion means for converting the RGB signal received by the receiving means to a format having a higher vertical resolution among the interlace format and progressive format which are preset video output formats based on the frequency detected by the means Are provided.

  The video signal receiving method according to the present invention includes a step of selectively receiving a plurality of types of RGB signals having different numbers of vertical lines, a step of detecting horizontal and vertical frequencies of the received RGB signals, and a detected frequency. The received RGB signals are converted into a format having a higher vertical resolution among the interlace format and progressive format, which are preset video output formats, and output.

  According to the above-described invention, the received RGB signal is converted into a format having a higher vertical resolution among the interlace format and progressive format, which are preset video output formats, according to the number of vertical lines, and is output. As a result, it is possible to prevent the deterioration of the vertical resolution.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 shows a video signal receiving apparatus 11 described in this embodiment. The video signal receiver 11 has a function of receiving a television broadcast signal and a function of receiving a plurality of types of RGB signals corresponding to VGA, SVGA, or XGA.

  That is, the television broadcast signal is received by the antenna 12 and supplied to the receiving unit 14 via the TV (television) input terminal 13. The receiving unit 14 extracts a signal of a predetermined channel from the input television broadcast signal and outputs it to the selector 15. The RGB signal supplied from the external PC 16 is supplied to the selector 15 via the input terminal 17.

  The selector 15 selects one of the two input video signals and outputs it to the signal processing unit 18. The signal processing unit 18 subjects the input video signal to demodulation processing by the video signal processing unit 19, and then performs format conversion processing in accordance with the display unit 21 at the subsequent stage by the output format conversion unit 20. . The video signal output from the signal processing unit 18 is supplied to the display unit 21 such as a CRT via the video output terminal 22 and is used for video display.

  Here, in the video signal receiving apparatus 11, all operations including the above-described various receiving operations are comprehensively controlled by the control unit 23. The control unit 23 includes a CPU (Central Processing Unit) and the like, receives operation information from the operation unit 24, or receives operation information sent from the remote controller 25 via the reception unit 26, Each part is controlled so that the operation content is reflected.

  In this case, the control unit 23 uses the memory unit 27. That is, the memory unit 27 mainly includes a read-only memory that stores a control program executed by the CPU of the control unit 23, a read / write memory that provides a work area for the CPU, and various setting information and control information. Non-volatile memory to be stored.

  Here, the video signal selected by the selector 15 is supplied to the detector 28. The detection unit 28 detects the horizontal and vertical frequencies and supplies the detection result to the control unit 23.

  Based on the frequency supplied from the detection unit 28, the control unit 23 converts the RGB signal into a format that can display the highest vertical resolution among the formats compliant with the display unit 21. The processing unit 18 is controlled.

  Specifically, it is assumed that the display unit 21 conforms to a 1080i (interlace) HD (High Definition) format video display with a horizontal frequency of 33.75 kHz and a vertical frequency of 60 Hz. In this case, it is necessary to perform format conversion so that the RGB signal corresponding to VGA, SVGA or XGA output from the PC 16 conforms to the display unit 21.

  However, since RGB signals are in a progressive format, it is desirable to display video in a progressive format without converting to an interlace format. In other words, in this case, in order to comply with the display unit 21, it is converted into a 540p (progressive) format with a horizontal frequency of 33.75 kHz and a vertical frequency of 60 Hz.

  However, if all types of RGB signals corresponding to VGA, SVGA or XGA are simply converted into a 540p format, the number of lines in the vertical direction is 768 in the case of a video signal in a format corresponding to XGA. Since the book is converted to 540, the vertical resolution is deteriorated and fine characters and the like appear blurred.

  Here, when compared using a coefficient representing the ratio of the effective vertical resolution to the number of scanning lines (Kel coefficient: k = 0.7), the vertical resolution at 1080i is 1080 × k = 756 lines, and at 540p. The vertical resolution is 540 lines. In other words, it can be seen that when the video is displayed at 1080i, the vertical resolution is about 1.4 times higher than when the video is displayed at 540p, and fine character display can be improved. This is the same for the RGB signal corresponding to SVGA having 600 vertical lines.

  To summarize the above, when the number of vertical lines of the received RGB signal is less than 540, that is, in the case of an RGB signal corresponding to VGA, it is converted into the 540p format to display an image, and the received RGB signal is displayed vertically. When the number of lines is 540 or more, that is, in the case of an RGB signal corresponding to SVGA or XGA, converting the image to 1080i format to display an image displays the highest vertical resolution on the display unit 21.

  2 and 3 are flowcharts summarizing the above operations. That is, the processing is started (step S1), and when the RGB signal is received in step S2, the detection unit 28 detects the horizontal and vertical frequencies of the received RGB signal in step S3, and the detection result is obtained. Output to the control unit 23.

  Then, in step S4, the control unit 23 determines whether or not the received RGB signal is compatible with VGA. If it is determined that the received RGB signal is VGA compatible (YES), in step S5. Various control data necessary for converting the RGB signal into the 540p format is set, and the control data is transmitted to the signal processing unit 18 in step S6. Thereby, the signal processing unit 18 converts the input RGB signal to 540p, 60 Hz and outputs it to the display unit 21 in step S7, and ends the processing (step S8).

  If it is determined in step S4 that the received RGB signal does not correspond to VGA (NO), the control unit 23 determines that the received RGB signal corresponds to SVGA in step S9. If it is determined that the signal is an RGB signal compatible with SVGA (YES), in step S10, various control data necessary for converting the RGB signal into the 1080i format are set, and step S11 is performed. Then, the control data is transmitted to the signal processing unit 18. Thereby, the signal processing unit 18 converts the input RGB signal into 1080i, 60 Hz and outputs it to the display unit 21 in step S12, and ends the processing (step S8).

  Furthermore, when it is determined in step S9 that the received RGB signal does not correspond to SVGA (NO), the control unit 23 determines that the received RGB signal corresponds to XGA in step S13. If it is determined that the signal is an RGB signal compatible with XGA (YES), in step S14, various control data necessary for converting the RGB signal into the 1080i format is set, and step S15 is performed. Then, the control data is transmitted to the signal processing unit 18. Thereby, the signal processing unit 18 converts the input RGB signal into 1080i, 60 Hz and outputs it to the display unit 21 in step S16, and ends the processing (step S8).

  If it is determined in step S13 that the received RGB signal does not correspond to XGA (NO), the control unit 23 determines that the RGB signal is not received in step S17, and performs processing. Is finished (step S8).

  FIG. 4 shows another embodiment of the present invention. In FIG. 4, the same parts as those in FIG. 1 are denoted by the same reference numerals. The operation unit 24 and the remote controller 25 convert the received RGB signals to 1080i format and display the video, or convert them to 540p format. The change-over switches 24a and 25a are provided for the user to switch whether the video is displayed.

  That is, in the above-described embodiment, the RGB signal corresponding to SVGA or XGA is converted into the 1080i format to display an image with a high vertical resolution. May occur and this may be noticeable. On the other hand, in the progressive format, line flicker does not occur, but the vertical resolution deteriorates compared to interlace.

  Therefore, after the format conversion corresponding to the number of vertical lines is performed on the received RGB signal by the operation described with reference to FIGS. 2 and 3, the user sees the actual display screen and switches the switches 24a and 25a. By switching between the 1080i format and the 540p format, it is possible to select the better image quality.

  It should be noted that the present invention is not limited to the above-described embodiments as they are, and can be embodied by variously modifying the constituent elements without departing from the scope of the invention in the implementation stage. Various inventions can be formed by appropriately combining a plurality of constituent elements disclosed in the above-described embodiments. For example, some components may be deleted from all the components shown in the embodiment.

BRIEF DESCRIPTION OF THE DRAWINGS The block diagram which shows embodiment of this invention and is shown in order to demonstrate a video signal receiver. The flowchart shown in order to demonstrate a part of main operation | movement of the video signal receiver in the embodiment. The flowchart shown in order to demonstrate the remainder of main operation | movement of the video signal receiver in the embodiment. The other embodiment of this invention and the block block diagram shown in order to demonstrate a video signal receiver.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 11 ... Video signal receiver, 12 ... Antenna, 13 ... TV input terminal, 14 ... Receiver, 15 ... Selector, 16 ... PC, 17 ... Input terminal, 18 ... Signal processor, 19 ... Video signal processor, 20 ... Output format conversion unit, 21 ... display unit, 22 ... video output terminal, 23 ... control unit, 24 ... operation unit, 25 ... remote controller, 26 ... reception unit, 27 ... memory unit, 28 ... detection unit.

Claims (10)

Receiving means for selectively receiving a plurality of types of RGB signals having different numbers of vertical lines;
Detecting means for detecting horizontal and vertical frequencies of the RGB signals received by the receiving means;
Based on the frequency detected by the detecting means, the RGB signal received by the receiving means is converted into a format with a higher vertical resolution among the interlace format and progressive format which are preset video output formats and output. A video signal receiving apparatus comprising: a conversion means for performing When the interlace format and progressive format, which are the preset video output formats, are 1080i and 540p, respectively.
The converting means converts an RGB signal having a number of vertical lines of less than 540 into a 540p format and outputs the signal, and converts an RGB signal having a number of vertical lines of 540 or more into a 1080i format and outputs the converted signal. Item 2. The video signal receiving device according to Item 1. A plurality of types of RGB signals with different numbers of vertical lines correspond to VGA, SVGA and XGA,
When the interlace format and progressive format, which are the preset video output formats, are 1080i and 540p, respectively.
2. The conversion unit according to claim 1, wherein the conversion unit converts the RGB signal corresponding to the VGA into a 540p format and outputs the converted signal, and converts the RGB signal corresponding to the SVGA and XGA into a 1080i format and outputs the converted signal. Video signal receiver. Receiving means for selectively receiving RGB signals corresponding to VGA, SVGA and XGA;
Detecting means for detecting the type of RGB signal received by the receiving means;
Conversion means for converting an RGB signal corresponding to the VGA into a 540p format based on a detection result of the detection means and outputting the converted signal, and converting an RGB signal corresponding to the SVGA and XGA into a 1080i format for output; A video signal receiving apparatus characterized by that.   5. The video signal receiving apparatus according to claim 1, further comprising an operation unit capable of switching whether the RGB signal received by the receiving unit is converted into an interlace format or a progressive format. . Selectively receiving a plurality of types of RGB signals having different numbers of vertical lines;
Detecting the horizontal and vertical frequencies of the received RGB signal;
A step of converting the received RGB signal into a format with a higher vertical resolution out of an interlace format and a progressive format, which are preset video output formats, based on the detected frequency, and outputting the same. A characteristic video signal receiving method. When the interlace format and progressive format, which are the preset video output formats, are 1080i and 540p, respectively.
7. An image according to claim 6, wherein an RGB signal having fewer than 540 vertical lines is converted to a 540p format and output, and an RGB signal having more than 540 vertical lines is converted to a 1080i format and output. Signal reception method. A plurality of types of RGB signals with different numbers of vertical lines correspond to VGA, SVGA and XGA,
When the interlace format and progressive format, which are the preset video output formats, are 1080i and 540p, respectively.
7. The video signal receiving method according to claim 6, wherein the RGB signal corresponding to the VGA is converted into a 540p format and output, and the RGB signal corresponding to the SVGA and XGA is converted into a 1080i format and output. Selectively receiving RGB signals corresponding to VGA, SVGA and XGA;
Detecting the type of received RGB signal;
And converting the RGB signal corresponding to the VGA into a 540p format based on the detection result and outputting the converted RGB signal corresponding to the SVGA and XGA into the 1080i format and outputting the converted signal. Video signal receiving method.   10. The video signal receiving method according to claim 6, further comprising a step of switching whether the received RGB signal is converted into an interlace format or a progressive format by an operation.

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