JP2010130643A - Image processor and image processing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To solve the following problem: there is an image causing adverse effects such as noise generation and picture quality deterioration due to a video processing technique such as high resolution processing. <P>SOLUTION: High resolution processing by a high resolution processing part 21 and moving image refinement processing by a moving image refinement processing part 22 are performed for an OSD image generated, so that a contrast rate is reduced with respect to color information such as illuminance and color difference used in a video signal outputted from a main processing part 8 together with an OSD image generated by the OSD generating part 8a and an OSD image analyzed by a high resolution control part 8b, by using parameter data for intermediate illuminance and intermediate color difference used in the OSD image stored in a ROM 9 and limited within a predetermined range. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an image processing apparatus and an image processing method.

  In recent years, with an increase in screen size, television receivers and monitors having a large number of display pixels, that is, having a high-resolution display, are widely used. In such a display, not only a moving image video of SD (Standard Definition; hereinafter referred to as SD) resolution such as a DVD or an analog video is displayed as it is but also HD (High Definition; A video with a resolution (hereinafter referred to as HD) can be displayed clearly. Furthermore, as a technology for increasing the resolution of video, a technique called super-resolution technology, which converts a video with low resolution into a video with high resolution by pixel interpolation, converts the video with SD resolution into HD. It is possible to display the image clearly even on a large screen by converting it to resolution.

For example, Patent Document 1 discloses a resolution conversion method in which pixels to be interpolated are determined based on surrounding pixels when performing pixel complementation from a low resolution to a high resolution.
Japanese Patent Laying-Open No. 2007-310837 (FIG. 1A)

  However, when processing technology that improves video image quality, such as high resolution technology, is implemented in an actual digital television, it can be seen that depending on the type of video, there may be adverse effects such as noise generation and image quality deterioration. It was.

  Therefore, in order to solve the above-described problems, the present invention provides an image processing apparatus and an image processing apparatus that generate an OSD image that is unlikely to have adverse effects such as noise generation and image quality deterioration when image processing technology such as high resolution processing is applied. A processing method is provided.

  In order to solve the above-described problems, the present invention provides video processing means for performing processing for increasing the resolution of content video based on a predetermined algorithm, a background having first color information, and a character string having second color information. An OSD generation unit that generates an OSD image including the image information, and when the processing by the video processing unit is performed, the OSD generation unit includes color information whose contrast ratio between the background and the character string is within about 95%. It is characterized by producing | generating using.

  In order to solve the above-described problems, the present invention provides a video processing means for performing a process for increasing the resolution of a content video based on a predetermined algorithm, a background having first color information, and a character string having second color information. And an OSD generating means for analyzing the color information of the content video, and the OSD generating means further determines the color determined based on the analyzed color information. In a state where the OSD image using information is generated, the video processing means performs a process of increasing the resolution of the content video and the OSD image.

  According to another aspect of the present invention, there is provided a video processing unit that performs at least an outline enhancement process of video, a selection unit that allows a user to select on or off of an operation related to the enhancement process, OSD generation means for generating an OSD image including a background having color information and a character string having second color information, and when the enhancement processing is turned on by the selection means, and the enhancement by the selection means And control means for changing color information of at least one of the first color information and the second color information when the processing is turned off.

  In order to solve the above-described problem, the present invention performs processing for increasing the resolution of content video based on a predetermined algorithm, and includes an OSD including a background having first color information and a character string having second color information. In the case where an image is generated and the resolution is increased, the image is generated using color information having a contrast ratio of about 95% or less between the background and the character string.

  In order to solve the above-described problem, the present invention performs processing for increasing the resolution of content video based on a predetermined algorithm, and includes an OSD including a background having first color information and a character string having second color information. An image is generated, color information of the content video is analyzed, and the OSD image is generated using the color information determined based on the analyzed color information, and the content video and the OSD image are generated. It is characterized by performing a process for increasing the resolution.

  In addition, in order to solve the above-described problem, the present invention performs at least an outline enhancement process of an image, permits a user to select on or off of an operation related to the enhancement process, and has a background having first color information. An OSD image including a character string having second color information is generated, and the first color information or the second color information depending on whether the enhancement processing is turned on or off. At least one of the color information is changed.

  According to the present invention, the color information of the OSD image is controlled in accordance with the application status of the video processing technology such as the resolution enhancement processing, so that it is possible to generate an OSD image that is unlikely to have adverse effects such as noise generation and image quality deterioration. .

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
(First embodiment)
FIG. 1 is a block diagram showing the configuration of the image processing apparatus according to the first embodiment. In the first embodiment, an example in which the image processing apparatus of the present invention is applied to a digital television is shown.

  The digital television 1 includes a digital tuner 2, a digital signal demodulator 3, an analog tuner 4, an external input signal processor 5, an IPTV signal processor 6, an Internet signal processor 7, a signal processor 8, an OSD generator 8a, a high resolution And a ROM 9, a high resolution processing unit 21, a moving image improvement processing unit 22, a display processing unit 23, a display 24, an audio processing unit 25, and a speaker 26.

  Digital broadcast waves such as BS, CS, and terrestrial waves received by the digital antenna ATd include data for data broadcasting and electronic program guide (EPG) in addition to video and audio. The digital tuner 2 selects a specific viewing channel designated by the user. The digital signal demodulator 3 demodulates the digital signal from the digital broadcast wave of the selected channel.

  The analog antenna ATa receives an analog broadcast. The analog tuner 4 selects a viewing channel designated by the user. The external input signal processing unit 5 performs processing of a selected analog broadcast signal and processing of an external input signal received from an external device GS such as a game machine, a PC (personal computer), or a DVD player.

  The IPTV signal processor 6 processes the received IPTV (Internet Protocol TV) broadcast signal. The internet signal processing unit 7 processes the received internet signal.

  The main processing unit 8 performs processing such as IP (interlace-progressive) conversion, NR (noise reduction) processing and scaling on the received video signal, separation processing of the video signal and the audio signal, and processing from the digital signal. In addition to performing processing such as data extraction, an OSD generation unit 8a that generates an OSD image and a high-resolution control unit 8b that controls the high-resolution processing unit 21 in the subsequent stage are configured.

  The OSD generation unit 8a generates an image for displaying the extracted data broadcast and electronic program guide (EPG) data as an OSD image, and a user interface image for operating the apparatus. In the first embodiment, an OSD image that does not deteriorate image quality even when the resolution enhancement processing is performed is also generated. The resolution enhancement control unit 8b analyzes color information such as luminance and color difference of the video signal output from the main processing unit 8, and controls the subsequent resolution enhancement processing unit 21 to perform resolution enhancement processing. .

  The ROM 9 stores a character string made up of characters or figures used for the OSD image generated by the OSD generation unit 8a, parameter data thereof, color information of the background, color information of the background, and the like. That is, the OSD generation unit 8a reads the parameter data stored in the ROM 9 and generates an OSD image.

  The high resolution processing unit 21 performs a process of increasing the resolution of the input video signal (image data). For example, when the received video signal is an SD resolution image, the pixels are restored so as to become an HD resolution image. Then, the video signal is sharpened by increasing the resolution.

  The moving image improvement processing unit 22 performs moving image improvement processing on the input video signal. The moving image improvement processing refers to processing a video signal so as to reproduce a video normally composed of 60 frames per second at 120 frames per second by a high-precision motion interpolation technique. By processing the video signal in this way, the video of moving parts such as horizontal, vertical, diagonal and rotating subjects is reduced, noise is also effectively suppressed, and the flowing telop and fast-moving sports scenes are clear. Can be displayed on the display 24 in the subsequent stage.

  The display processing unit 23 further adjusts the brightness and hue of the adjusted video signal. The display 24 displays the video signal on the screen. Then, the viewer views the television image by looking at the screen of the display 24. The audio processing unit 25 performs acoustic processing and amplifies the audio signal. The speaker 26 outputs an audio signal as audio. The viewer listens to the television sound by listening to the sound from the speaker 26.

  In the first embodiment, the OSD image generated by the OSD generation unit 8 a is superimposed on the video signal output from the main processing unit 8. That is, the resolution enhancement process and the operation improvement process are embodiments in which a process is performed on a video in which an OSD image is superimposed on a video signal of content.

  And, when emphasizing the contour (edge) of the video signal image, which is one of the effects of high resolution processing, the resolution is further enhanced according to the contrast ratio of adjacent colors. Is applied. That is, the contrast is further enhanced for the edge of a video having a large ratio of adjacent colors, while the contrast is hardly enhanced for an edge having a small contrast ratio.

  In other words, the ROM 9 stores parameter data having a small contrast ratio between the character string and the background so that the edge enhancement effect described above is not applied to the OSD image. In addition, the OSD image is displayed so as to be superimposed on the video signal of unspecified luminance output from the main processing unit 8, and the luminance of the output video signal varies depending on the content. Even when an OSD image is arranged on a luminance video signal, the ROM 9 particularly stores parameter data using intermediate luminance or intermediate color difference as color information of the background of the OSD image so that the contrast ratio with the video signal becomes small. To do.

  Specifically, when generating an OSD image with a black background and a white character string, parameter data in which the brightness of white is reduced so that the contrast ratio between the black background and the white character string is 95% or less. Alternatively, the ROM 9 stores parameter data in which the luminance of black is increased. Even when other colors are used for the background and the character string, the ROM 9 stores parameter data with a contrast ratio of 95% or less. The specific example described above will be further described with reference to FIG.

FIG. 2 is a diagram showing an embodiment of the effect of the high resolution processing on the OSD image according to this embodiment.
Here, description will be made using color gradation as a parameter for determining luminance.
FIG. 2A shows a case where high resolution processing having an edge enhancement effect is applied to an OSD image using black of gradation 0% for the background and white of gradation 100% for the character string. It shows the situation. If an image with a contrast ratio of 100% is subjected to high resolution processing, the edge that is the boundary between the background and the character string is overemphasized, resulting in an image with noticeable noise, which is difficult to see.

  FIG. 2B shows a high resolution processing having an edge enhancement effect for an OSD image using 2.5% gradation black for the background and 97.5% gradation white for the character string. It shows the state when applied. When the high resolution processing is performed on an image with a contrast ratio of 95%, the background and the edge of the character string are not emphasized, and the effect of the high resolution processing is not so effective on the OSD image. .

  More specifically, when the setting resolution of each of RGB of the block for determining the color gradation based on the digital value provided in the main processing unit 8 or the image quality improvement processing unit 21 is 8 bits (256 resolution). Black with gradation 0% is (R, G, B) = (0, 0, 0), and white with gradation 100% is (R, G, B) = (255, 255, 255). . That is, the set values of RGB for expressing black or white are black at the minimum level and white at the maximum level. On the other hand, black with a gradation of 2.5% is (R, G, B) = (7, 7, 7), and white with a gradation of 97.5% is (R, G, B) = (249, 249). 249). For example, if the set value representing black is further increased, black will change to gray as the set value increases. Similarly, if the set value representing white is further decreased, the set value will decrease. , White turns gray. That is, (R, G, B) = (127, 127, 127) is completely expressed as gray.

  In other words, if the contrast ratio is lowered, the difference between the two gradations can be reduced, and the effect of the high resolution processing can be reduced. However, since black cannot be recognized as black or white cannot be recognized as white, the high resolution processing is performed. The lower limit of the contrast ratio for reducing the effect is limited by about 90%. Then, the setting value in consideration of such a problem is the above-described contrast ratio of 95%.

  That is, in order to suppress the effect of the high resolution processing on the OSD image, it is only necessary to use parameter data in which the contrast ratio of the colors used in the image is small to some extent.

  As described above, according to the first embodiment, the ROM 9 stores parameter data in which the contrast ratio between the background of the OSD image and the character string included in the image to be subjected to the high resolution processing is equal to or less than a predetermined value. Even if high resolution processing is performed on an image including an OSD image, an image without deterioration in image quality due to excessive edge enhancement can be obtained.

(Second Embodiment)
The second embodiment is basically the same as the configuration of the image processing apparatus of the first embodiment, but the method for determining the parameter data of the OSD image background and character string color information is different. 3 will be described below.

FIG. 3 is a flowchart of a resolution enhancement process involving an OSD image output determination process according to the present embodiment.
First, the resolution enhancement control unit 8b determines whether to output an OSD image together with the content video signal (S301). If no OSD image is involved (N in S301), the high resolution processing unit 21 is controlled to perform high resolution processing (S305). On the other hand, when accompanied by an OSD image (Y in S301), the high resolution control unit 8b analyzes color information such as luminance and color difference used in the video signal of the content output from the main processing unit 8 ( S302).

  Since the ROM 9 stores a plurality of patterns having different color information of the background and the character string of the specific OSD image, the OSD generation unit 8a converts the color information of the analyzed video signal into a high resolution control unit. The parameter data acquired from 8b and having a small contrast ratio with respect to the acquired color information is selected from the ROM 9 (S303). The parameter data stored in the ROM 9 may be in a form in which the color difference used for the OSD image background and the character string is one set, and the contrast ratio with the video signal is reduced by changing the luminance.

  Further, the OSD generation unit 8a generates and outputs an OSD image using the selected color information (S304), and the high resolution control unit 8b controls the high resolution processing unit 21 to perform the high resolution processing. (S305).

The specific example described above will be further described with reference to FIG.
FIG. 4 is a diagram showing an embodiment of the influence of the high resolution processing on the OSD image and the content video according to this embodiment.
Here, description will be made using color gradation as a parameter for determining luminance.
FIG. 4A shows an OSD image in which 2.5% gradation black is used for the background of the OSD image and white gradation of 97.5% is used for the character string, and 100% gradation white is used as a basic tone. Shows a state when the high resolution processing having an edge enhancement effect is performed on the video displayed on the same screen.

  Since the contrast ratio between the content video and the background of the OSD image is 100%, when the high resolution processing is performed on the video, the edge that is the boundary between the content video and the background of the OSD image is emphasized. Too much noise makes the image stand out, making it difficult to see.

  FIG. 4B is based on an OSD image in which 5% gradation black is used as the background of the OSD image and white in gradation 97.5% is used for the character string, and white in gradation 100%. The content video shows a state when a high resolution processing having an edge enhancement effect is performed on a video displayed on the same screen. That is, in the ROM 9, as parameter data of the OSD image, a parameter pattern a consisting of black with a gradation of 2.5% on the background and white with a gradation of 97.5% on the character string, and a gradation of 5% on the background. A specific example is shown in which a parameter pattern b composed of black and white of gradation 97.5% is stored in a character string, and the pattern b is selected.

  Since the contrast ratio between the content video and the background of the OSD image is 95%, when the resolution enhancement processing is performed on this video, the background and the edge of the character string are not so emphasized, and the OSD image Is in a state where the effect of the high resolution processing is not so effective.

By the way, the processing described above may be performed on all frames of the video signal output from the main processing unit 8 or may be performed at predetermined frame intervals.
As described above, according to the second embodiment, before performing high resolution processing, color information such as luminance and color difference used in the video signal of the content output from the main processing unit 8 is analyzed. As a result, an OSD image using color information having a small contrast ratio with the color information of the analyzed video is generated. Therefore, even if the high resolution processing is performed on the OSD image together with the content video, the OSD image has a peripheral portion. Therefore, it is possible to perform high resolution processing without image quality deterioration due to excessive edge enhancement.

  In the above-described embodiment, the parameter data for reducing the contrast ratio between the background of the OSD image and the character string has been described. However, the parameter data for reducing only the luminance of the background and the character string, or the parameter for reducing only the color difference. It may be data. Furthermore, for the same purpose, adjustment of the outline shape of the background of complex shapes, change of the line width of the character string, intermediate luminance and intermediate color difference between the background and the character string, the outline of the background, etc. A form in which processing such as addition of graphics, translucency of background color or character string color, and the like may be performed.

  In the above-described embodiment, the description has been made on the premise that the high resolution processing is always performed. However, it may be configured to select whether or not the high resolution processing is to be performed. Note that the selection may be in the form that the user makes, or the apparatus may automatically control the resolution of the input signal using a means for determining.

  In such an embodiment, the operations of the first and second embodiments described above are performed only in a state where the high resolution processing is performed, and the contrast ratio is set in a state where the high resolution processing is not performed. An OSD image is generated using arbitrary color information without consideration. In other words, when high resolution processing is performed, the color data parameter data used in the OSD image may be optimized.

  Furthermore, the high resolution processing has been described so far as an embodiment in which the video signal is sharpened by restoring pixels, and the edge portion of the video is emphasized as one of the effects. The form to emphasize may be sufficient. Further, not only the edge enhancement effect but also the hue optimization effect may be used. Further, a parameter for reducing the interference of the OSD image with the content video signal subjected to the moving image improving process may be set not by the effect of the high resolution processing unit but by the effect of the moving image improving process.

  Moreover, although embodiment applied to the digital television 1 as an image processing apparatus of this invention was described, the display 24, the display process part 23, the audio | voice process part 25, and the speaker 26 are not provided, for example, a tuner, a set top box, The image processing apparatus of the present invention can also be applied to the embodiment of the display 24, and the embodiment of the HDD recorder, for example, which is not provided with the display 24 and the speaker 26 but includes a recording medium (not shown).

  The present invention is not limited to the above-described embodiments, and various changes and modifications can be made without departing from the scope of the present invention.

1 is a block diagram illustrating a configuration of an image processing apparatus according to an embodiment. The figure which shows one Embodiment of the influence by the high resolution process with respect to the OSD image by this embodiment. 6 is a flowchart of a resolution enhancement process involving an OSD image output determination process according to the embodiment. The figure which shows one Embodiment of the influence of the high resolution process with respect to each of the OSD image and content image | video by this embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Digital television, 2 ... Digital tuner, 3 ... Digital signal demodulation part, 4 ... Analog tuner, 5 ... External input signal processing part, 6 ... IPTV signal processing part, 7 ... Internet signal processing part, 8 ... Main processing part, 8a ... OSD generation unit, 8b ... high resolution control unit, 9 ... ROM, 21 ... high resolution processing unit, 22 ... moving image improvement processing unit, 23 ... display processing unit, 24 ... display, 25 ... audio processing unit, 26 … Speaker.

Claims (10)

Video processing means for performing processing for increasing the resolution of the content video based on a predetermined algorithm;
OSD generating means for generating an OSD image including a background having first color information and a character string having second color information;
Comprising
When the processing by the video processing means is performed, the OSD generation means generates the OSD image using color information whose contrast ratio between the background and the character string is about 95% or less. apparatus. A memory for storing parameters of the first color information and the second color information;
The image processing apparatus according to claim 1, wherein the OSD generation unit generates the OSD image using a parameter stored in the memory.   The image processing apparatus according to claim 2, wherein the memory stores parameters of intermediate luminance and intermediate color difference.   The video processing means restores a video signal having a second resolution higher than the first resolution by estimating an original pixel value from the video signal having the first resolution and increasing the number of pixels. The image processing apparatus according to 1. Video processing means for performing processing for increasing the resolution of the content video based on a predetermined algorithm;
OSD generating means for generating an OSD image including a background having first color information and a character string having second color information;
Analyzing means for analyzing color information of the content video;
Comprising
The OSD generation unit determines color information of a background and a character string based on the analyzed color information, and generates the OSD image including the background and the character string having the determined color information.
The image processing apparatus, wherein the video processing means performs processing for increasing the resolution of the content video and the OSD image. Video processing means for performing at least image contour enhancement processing;
Selection means for allowing the user to select on or off of the operation related to the enhancement processing;
OSD generating means for generating an OSD image including a background having first color information and a character string having second color information;
Either the first color information or the second color information is selected when the enhancement unit is turned on by the selection unit and when the enhancement unit is turned off by the selection unit. Control means for controlling the color information of the character string or for changing the shape of the character string;
An image processing apparatus comprising:   The control means is configured such that the contrast ratio between the background and the character string is smaller when the emphasis process is turned on by the selection means than when the emphasis process is turned off by the selection means. The image processing apparatus according to claim 6, wherein the image processing apparatus is controlled. Perform processing to increase the resolution of content video based on a predetermined algorithm,
Generating an OSD image including a background having first color information and a character string having second color information;
An image processing method, wherein when the processing for increasing the resolution is performed, the background information and the character string are generated using color information having a contrast ratio of about 95% or less. Perform processing to increase the resolution of content video based on a predetermined algorithm,
Generating an OSD image including a background having first color information and a character string having second color information;
Analyzing the color information of the content video;
Based on the analyzed color information, color information of a background and a character string is determined, and the content video and the OSD image are generated in a state where the OSD image including the background and the character string having the determined color information is generated. An image processing method characterized by performing a process for increasing the resolution of the image. Perform at least the outline enhancement of the video,
Allowing the user to select on or off of the operation related to the enhancement processing;
Generating an OSD image including a background having first color information and a character string having second color information;
Either the color information of at least one of the first color information or the second color information is changed depending on whether the enhancement processing is turned on or off, or the character string An image processing method characterized by changing the shape of the image.

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