JP5114274B2 - Television receiver and frame rate conversion method thereof - Google Patents

Description

  The present invention relates to a video display technique for a television receiver, and more particularly, to a television receiver and a video display method thereof that prevent deterioration in image quality when still images such as characters are superimposed on a moving image. .

  2. Description of the Related Art Conventionally, in a television receiver that can receive digital broadcasts, for example, in motion pictures such as movies and commercials, a frame rate conversion (frame rate conversion) using a motion vector for a video signal for the purpose of improving image quality. (Increase in the number of frames), and it is already known to perform video display as a moving image of smooth change by performing frame interpolation.

  For example, according to the following Patent Document 1, as a conventional technique for performing frame interpolation by frame rate conversion, in particular, as a frame rate conversion technique that enables smoother motion of video and display of high-quality video, interpolated frames The first frame that appears at a time before the interpolation frame, the second frame that appears at a time before the first frame, and a time after the insertion time Using the information of the third frame appearing at the time and the fourth frame appearing at a time later than the third frame, detecting the motion vector of the moving image to determine the interpolation direction; and A technique is described in which an interpolation frame is generated by creating an interpolation pixel from the pixels of the second frame and the third frame in the determined interpolation direction, and is inserted into the input video signal. It has been.

  On the other hand, in television receivers, OSD (On Screen Display) display with still images including characters and figures is widely adopted to introduce broadcast programs and perform various functions and operations of the device. In many cases, still images are displayed on the moving image.

JP 2006-165602 A

  As described above, when a still image is displayed overlaid on a moving image, particularly when a frame rate conversion process is performed on a video signal obtained by overlapping the still image on the moving image, a still image is displayed. In the case of a certain OSD image, in particular, a boundary portion thereof, and a halftone OSD image, noise is generated in a portion where the back image and the OSD that can be seen through the OSD portion intersect, and degradation of image quality becomes a problem. .

  Therefore, the present invention has been achieved in view of the above-described problems in the prior art, that is, even when an OSD image that is a still image such as a character is superimposed on a moving image, the image is displayed. It is an object of the present invention to provide a television receiver and an image display method thereof in which the image quality does not deteriorate.

  In addition, the generation of noise at the boundary between the OSD image in the image after the frame rate conversion process described above, and in the portion where the OSD intersects with the back image seen through the OSD part in the case of a halftone OSD image, According to the study by the inventor, a part of the still image is dragged by the frame rate conversion, that is, the motion of the moving image behind it, particularly at the boundary between the still image and the OSD image that is a moving image. This is considered to be caused by the FRC process being performed.

  That is, the present invention has been made on the basis of the above-mentioned knowledge by the present inventor. More specifically, in order to achieve the above-described object, first, a video signal including a moving image is interpolated into frames and stopped. A television receiver that displays an image together with an OSD image, which is an image, that interpolates a video signal including a moving image and displays the image together with an OSD image. An image quality correcting unit that corrects image quality, an OSD image inserting unit that inserts an OSD image into a video signal including a moving image from the image quality correcting unit, and a moving image in which an OSD image is inserted and output from the OSD image inserting unit. A frame rate conversion unit that performs frame rate conversion on the included video signal, and a display unit that displays the video signal output from the frame rate conversion unit. The frame rate conversion unit performs frame rate conversion with moving image frame interpolation for a video including a moving image on a one-frame screen to display the video, while moving image frame interpolation is performed for the OSD image. A television receiver is provided that performs no frame rate conversion.

  According to the present invention, in the television receiver described above, the frame rate conversion unit includes a first conversion unit that performs frame rate conversion with the moving image frame interpolation, and a frame without the moving image frame interpolation. A second conversion unit that performs rate conversion; an output from the first conversion unit; and an output from the second conversion unit, a video unit including a moving image on a one-frame screen for displaying the video; It is preferable to include a switching unit that selectively controls corresponding to the position information of the OSD image, and further includes a control unit for controlling the switching unit of the frame rate conversion unit. The control unit preferably includes a memory in which position information of the OSD image is recorded.

  Furthermore, according to the present invention, in order to achieve the above-described object, a television receiver for interpolating a video signal including a moving image and displaying a video together with a still image is provided. An image quality correction unit that corrects image quality, a frame rate conversion unit that performs frame rate conversion on a video signal including a moving image from the image quality correction unit, and a display unit that displays a video signal output from the frame rate conversion unit And a television further comprising an OSD image insertion unit that inserts an OSD image into a part of a video signal that is output from the frame rate conversion unit and includes a moving image in which a still image is inserted. A receiver is provided.

  In addition, according to the present invention, there is also provided a frame rate conversion method in a television receiver for interpolating a video signal including a moving image and displaying an image together with an OSD image in order to achieve the above-described object. Image quality correction for correcting the image quality of a video signal including a moving image is performed, an OSD image is inserted into the video signal including the corrected moving image, and frame rate conversion is performed on the video signal including the moving image in which the OSD image is inserted. When performing the frame rate conversion, the frame rate conversion with moving image frame interpolation is performed on the video including the moving image on the one-frame screen for displaying the video, while the OSD image is A frame rate conversion method for performing frame rate conversion without moving picture frame interpolation is provided.

  In order to achieve the above object, according to the present invention, there is also provided a frame rate conversion method in a television receiver for interpolating a video signal including a moving image and displaying an image together with an OSD image. The image quality correction for correcting the image quality of the video signal including the moving image is performed, the frame rate conversion is performed on the video signal including the moving image on which the image quality correction has been performed, and the OSD is performed on the video signal including the frame rate converted moving image. There is provided a frame rate conversion method in which an image is inserted and a video signal including a moving image in which the OSD image is inserted is displayed on a display unit.

  That is, according to the present invention described above, frame rate processing is performed in which a part of the OSD image is dragged by the motion of the moving image behind it at the boundary between the OSD image that is a still image and the moving image. Therefore, the generation of noise at the boundary portion of the OSD image in the video after the frame rate conversion process can be suppressed. As a result, it is possible to provide a television receiver with excellent display performance that does not deteriorate image quality even when an OSD image such as a character is superimposed on a video image, and a video display method therefor. Exhibits an excellent effect.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

  First, FIG. 1 attached is a block diagram showing an overall configuration of a television receiver according to an embodiment of the present invention.

  In FIG. 1, a broadcast video signal such as a digital broadcast signal is received by an antenna 1 and input to a switching unit 4 via a tuner 2. On the other hand, for example, a video signal from an external device such as distribution information is input to the switching unit 4 via the external video input terminal 3. In other words, the switching unit 4 receives a signal from the antenna 1. Either a broadcast video signal or a video signal from the external video input terminal 3 is selected. In the following description, it is assumed that the broadcast video signal received by the antenna 1 is selected by the switching unit 4.

  That is, the broadcast video signal is further input to the I / P conversion unit 5, where the I / P conversion unit 5 performs I / P conversion, thereby converting it into a video signal for sequential scanning (P scanning). Is done. Next, the video signal is input to the scaling unit 6, the resolution is converted by the scaling unit 6, and the resolution is converted to a resolution higher than the resolution of the display panel 10 as a display unit. For example, the display panel 10 is a high-definition (HD) panel having a horizontal resolution of 1920 and a vertical resolution of 1080, and the resolution of the broadcast video signal input to the scaling unit 6 is also the horizontal resolution of 1920. When the vertical resolution is 1080, the scaling unit 6 converts the resolution of the broadcast video signal so that the horizontal resolution is 1920 + A (A> 0) and the vertical resolution is 1080 + B (B > 0). Here, these A and B are numerical values of about 5% or less of the panel resolution. For example, if the horizontal resolution of the panel is 1920, the value of A is 96 or less, and if the resolution in the vertical direction is 1080, the value of B is 54 or less. The values of A and B are preferably about 5 to several tens. That is, when the video format of the video signal is detected, the scaling unit 6 is controlled based on the resolution conversion information set in advance corresponding to the video format so that the resolution of the video signal is 1920 + A in the horizontal direction and vertical. Make 1080 + B in the direction.

  The video signal whose resolution has been converted in this manner is then input to the image quality correction unit 7 where image quality correction such as gamma correction and color correction is performed. The image signal subjected to the image quality correction is further inserted with data necessary for OSD display (hereinafter referred to as an OSD image) for introducing a broadcast program and performing various functions and operations of the apparatus in the OSD processing unit 8. The That is, in the OSD processing unit 8, a video signal from the image quality correction unit 7 whose amplitude is multiplied by β through an amplifier 81 and OSD data (still image) whose amplitude is multiplied by α through an amplifier 82. Are added (overlapped) by the adder 83. The OSD data (still image) is provided in a part of a microcomputer 20 that controls the television receiver, and part of the OSD data is necessary for OSD display including characters and figures. Is output from the OSD data memory 21 for storing various data (OSD data). The OSD data memory 21 stores not only the OSD data but also the positional information on the 1-frame screen into which the OSD data (still image) is inserted, and the OSD image corresponds to the OSD data. Based on the position information, it is inserted at a predetermined position on the one-frame screen. In addition, α and β are in a relationship of β = 1−α; 0 ≦ α ≦ 1. As apparent from the figure, the microcomputer 20 receives a light control signal such as infrared light emitted from a remote controller (remote controller) 30 for operating the television receiver by the remote controller light receiving unit 22. It will be apparent to those skilled in the art to input and perform the predetermined control.

  Thereafter, the signal from the image quality correction processing unit including the I / P conversion unit 5, scaling unit 6, image quality correction unit 7, and OSD processing unit 8 is further input to the frame rate conversion unit 9. The frame rate conversion unit 9 performs frame rate conversion, so-called frame interpolation. In the embodiment of the present invention, the frame rate conversion unit 9 performs normal frame rate conversion on the video signal, that is, the normal frame rate conversion unit 91 and the OSD that performs frame interpolation on the still image. In addition to the area frame rate conversion unit 92, the frame rate conversion unit 92 further includes a switching unit 93 including a switch for switching outputs from the two conversion units. More specifically, the normal frame rate conversion unit 91 performs frame rate conversion using a motion vector on the video signal from the image quality correction processing unit, particularly the moving image portion. By performing frame interpolation including moving image motion (moving image frame interpolation), a smoothly changing moving image is obtained (hereinafter, “normal frame rate conversion” is also referred to as “motion compensated frame rate conversion”). On the other hand, the OSD area frame rate conversion unit 92 performs frame interpolation on the OSD image superimposed on the video signal in the OSD processing unit 8. That is, frame interpolation including motion is not performed (still image frame interpolation), and the frame is repeated as a still image (hereinafter, this frame rate conversion is also referred to as “repeat conversion” or “repeat frame rate conversion”).

  Here, the normal frame rate conversion unit 91 creates an interpolation frame to be inserted into the frame sequence of the video signal from at least two frames included in the video signal. For example, a motion vector of a pixel of interest in an interpolation frame is detected from two video signal frames sandwiching the interpolation frame, and a filtering process (weighted average) is performed on the pixels of the two frames indicated by the detected motion vector. As a result, the interpolation pixels constituting the interpolation frame are generated. By performing this interpolation pixel on all the pixels in the interpolation frame, an interpolation frame is created. A specific example of this interpolation frame creation will be described below with reference to FIG.

  FIG. 5 shows an operation of the normal frame rate conversion unit 91. In this example, a motion vector is obtained from two frames before and after the interpolation frame, an interpolation frame is created using the motion vector, and frame interpolation is performed. is there. The pixel-by-pixel motion vector is calculated by obtaining a pair of pixels on the preceding and following frames that are point-symmetric with respect to the interpolation pixel in the interpolation frame.

  In FIG. 5, the x axis indicates the horizontal direction of the frame, the y axis indicates the vertical direction of the frame, and t indicates the frame time direction. Here, an interpolation pixel in the interpolation frame # 3 'is P03, and its coordinates are (0, 0). Search windows W2 and W4 indicating a motion vector search range are set for each of the previous frame # 2 and the subsequent frame # 4. The search window W2 of the previous frame # 2, for example, is centered on a pixel in the previous frame # 2 that is spatially the same position as the interpolated pixel P03, that is, a pixel P02 that is at a position intersecting the axis L of the previous frame # 2. It has a size of 7 pixels in the x-axis direction and 7 pixels in the y-axis direction. Similarly, the search window W4 of the subsequent frame # 4 is, for example, centered on the pixel in the previous frame # 2 that is spatially the same position as the interpolated pixel P03, that is, the pixel P04 that intersects the axis L of the previous frame # 4. The size is 7 pixels in the x-axis direction and 7 pixels in the y-axis direction. The coordinates of the pixels P02 and P04 are also (0, 0).

  Next, a straight line passing through the search window W2 of the previous frame # 2 and the search window W4 of the subsequent frame # 4 is set around the interpolation pixel P03. For example, if the coordinates of the pixel at the upper left corner of the search window W2 are (−3, 3), the pixel in the search window W4 on the straight line connecting this pixel and the interpolation pixel P03 becomes the pixel at the lower right corner. The coordinates are (3, -3). This straight line is set for all the pixels in the search windows W2 and W4. In this example, since the number of pixels in the search windows W2 and W4 is 7 × 7 = 49, 49 straight lines are set as straight lines passing through the interpolation pixel P03.

  Next, for each of the 49 straight lines, the difference between the pixels in the search window W2 through which each straight line passes and the pixels in the search window W4 is calculated. Here, the difference between the luminance signals of the respective pixels is obtained. A straight line having a pair of pixels with the smallest difference is set as the motion vector of the interpolation pixel P03. In the example of FIG. 5, the pair of the pixel P12 (coordinate is (2, 2)) in the search window W2 and the pixel P14 (coordinate is (−2, −2)) in the search window W4 has the smallest difference. To do. Accordingly, a straight line connecting the pixel P12, the interpolation pixel P03, and the pixel P14 is set as the motion vector MV of the interpolation pixel P03. That is, the pixel P12 in the previous frame # 2 passes through a pixel that is positionally equal to the interpolation pixel P03 in the interpolation frame # 3 according to the direction indicated by the motion vector MV, and then passes to the pixel P14 in the subsequent frame # 4. Move.

  Then, an interpolation pixel P03 is created using this motion vector MV. For example, the interpolation pixel P03 is created by calculating the average value of the pixel P12 in the previous frame # 2 through which the motion vector MV passes and the pixel P14 in the subsequent frame # 4. Further, the interpolation pixel P03 may be obtained by calculation according to the following equation 1.

P03 = k · P02 + (1−k) · P04 (where k <1) (Equation 1)
Here, k is a coefficient indicating weighting, that is, a mixture ratio of both pixels. For example, the distance between the interpolation frame # 3 ′ and the previous frame # 2, and the interpolation frame # 3 ′ and the subsequent frame # 4 You may set according to time distance. In the first embodiment, since the time intervals between the frames are assumed to be equal, an average value of two pixels is obtained with k = 0.5. An interpolation frame # 3 ′ can be created by performing this calculation for all the interpolation pixels of the interpolation frame # 3 ′. The created interpolation frame # 3 ′ is stored in the frame memory in the normal frame rate conversion unit 91, and is read out and output at the display timing of the interpolation frame # 3 ′.

  The interpolation frame output in this way is inserted into the frame sequence of the video signal. If this interpolated frame is inserted between each frame of the video signal, for example, when the frame rate of the input video signal is 60 Hz, this can be converted to 120 Hz. Also, if one interpolation frame is inserted for every two consecutive frames of the video signal, when the frame rate of the input video signal is 60 Hz, this can be converted to 90 Hz. In addition, by replacing a repetitive frame included in the 2-3 pull-down video signal with an interpolation frame, the motion can be smoothed while the frame rate is kept at 60 Hz.

As described above, the normal frame rate conversion unit 91 detects a motion vector from a plurality of frames included in a video signal, creates an interpolation frame based on the motion vector, and performs frame rate conversion. For this reason, when an OSD image that is not related to the video signal is included in the signal of the base frame for creating the motion vector, one end of the motion vector indicates a part of the OSD image and the other end is a part of the video signal. May be indicated. In this case, in the processing as described above, the interpolation pixel in the interpolation frame is a weighted average of the OSD image and the video signal. That is, in such a case, an OSD image not related to the video signal is mixed in the interpolation frame, and the mixed portion is seen as noise.

  Therefore, in the present embodiment, as described above, the OSD area frame rate conversion unit 92 that performs the frame rate conversion without detecting the motion vector for the OSD image, that is, the process of increasing the number of frames by repeating the same image is provided. Provided. Accordingly, when an OSD image is synthesized with the video signal, the OSD image is prevented from being mixed in an area corresponding to the video signal of the interpolation frame. That is, this embodiment is characterized in that when an OSD image is synthesized with a video signal, the frame rate method is switched between the display area of the OSD image and other areas. Such switching will be described below.

  The switching unit 93 controls the switching operation based on the output from the microcomputer 20. For example, when the control signal from the microcomputer 20 is “1”, the switching unit 93 switches to the “A” terminal side in FIG. The signal from the rate conversion unit 91 is output. On the other hand, in the case of “0”, the signal is switched to the “B” terminal side in the figure, and the signal from the OSD area frame rate conversion unit 92 is output. The video signal output from the frame rate conversion unit 9, particularly the switching unit 93 is then input to the display panel unit 10 and displayed on the display screen. A synchronization signal from the I / P conversion unit 5 of the image quality correction processing unit is input via the synchronization detection unit 23, and a control signal “1” or “0” is output to the switching unit 93 based on the synchronization signal. To do.

  Next, the operation of the television receiver whose detailed configuration has been described above, in particular, the frame rate conversion unit 9 after OSD processing will be described in detail with reference to FIG. In FIG. 2, the horizontal axis (x-axis) indicates a horizontal synchronization signal (H-SYNC), and the vertical axis (y-axis) indicates a vertical synchronization signal (V-SYNC). For example, an operation of frame rate conversion in a case where an uppercase letter “A” of an alphabet is superimposed and displayed as an example of an OSD signal on a video signal for one frame including a moving image will be described.

  As is apparent from FIG. 2, the video signal including the moving image is sequentially obtained with respect to the signal for each pixel from the address (0, 0) to (1919, 1979) of the video signal for one frame. Predetermined processing is performed by the correction processing unit and output. On the other hand, in the microcomputer 20, OSD data including characters and figures displayed as OSD and its position information are stored in the OSD data memory 21, and the OSD data memory 21 reaches the position (address) where the OSD is displayed. (When (x1, y1) is reached in the example in the figure), the data stored in the memory 21 (for example, (R, G, B) indicating the display color = (50, 70, 100) ) And the like) are output to the OSD processing unit 8 of the image quality correction processing unit, so that a desired OSD display (in the example shown in the figure, the capital letter “A” of the alphabet) is superimposed and displayed. Therefore, when the video signal output from the image quality correction processing unit is within the area (area) of the video signal including the moving image, the microcomputer 20 controls the switching unit 93 of the frame rate conversion unit 9. When the output video signal reaches the OSD display area (area), the control signal “0” is output.

  That is, according to the above-described embodiment, among the displayed video signals, a video signal including a moving image is subjected to frame interpolation by the normal frame rate conversion unit 91 of the frame rate conversion unit 9, and the output thereof The signal is displayed on the display panel 10. On the other hand, the OSD area frame rate conversion unit 92 repeats a frame as a still image (repeat conversion is performed) for an OSD signal including characters, graphics, and the like displayed as an OSD image in the displayed video signal. ). According to this, the generation of noise at the boundary portion of the still image can be suppressed without being dragged by the frame rate conversion at the boundary portion between the still image and the OSD image, which is a moving image, as in the prior art. It becomes possible. It will be apparent that the same effect can be obtained by replacing the repeat conversion (repeat frame rate conversion) with a frame rate conversion by linear interpolation (average interpolation) (hereinafter also referred to as “linear frame rate conversion”). .

  FIG. 3 attached herewith shows an example of a display image including an OSD image obtained by the television receiver and the frame rate conversion method according to the embodiment of the present invention described above. That is, as is clear from this figure, it can be seen that a good display without flickering can be obtained due to the occurrence of noise in the outline of the OSD display part indicated by the broken line in the figure.

  By the way, in the above-described embodiment (Example 1), in particular, as described above, in addition to the switching unit 4, the I / P conversion unit 5, the scaling unit 6, and the image quality correction unit 7, the video image includes a moving image. This is a preferred embodiment when an OSD processing unit 8 that inserts data necessary for OSD display (OSD data) into a signal and is integrated as an image quality correction processing unit, which is a preferred embodiment, and is a normal frame rate conversion unit. In addition to 91 and the OSD area frame rate conversion unit 92, a frame rate conversion unit 9 which incorporates a switching unit 93 and is integrated into an IC is employed. However, the present invention is not limited to this, and the following embodiments are also possible.

  Subsequently, a television receiver according to another embodiment (Example 2) of the present invention will be described in detail below with reference to FIG. In this figure as well, the same reference numerals as those in FIG. 1 indicate the same components as described above. In this other embodiment (Example 2), as apparent from the figure, the image quality correction processing unit is configured by the switching unit 4, the I / P conversion unit 5, the scaling unit 6, and the image quality correction unit 7. Constitute. Then, the video signal from the image quality correction processing unit is subjected to frame rate conversion of the video signal by the frame rate conversion unit 9 ′ which is an IC including only the above-described normal frame rate conversion unit, and frame interpolation (video frame interpolation) is performed. )I do.

  Thereafter, the OSD processing unit 8 'inserts data (OSD image) necessary for OSD display for introducing a broadcast program and performing various functions and operations of the apparatus. Also in the OSD processing unit 8 ′, the video signal from the image quality correction unit 7 whose amplitude is multiplied by β through the amplifier 81 and the OSD data (still image) whose amplitude is multiplied by α through the amplifier 82. .Beta. = 1-.alpha .; 0.ltoreq..alpha..ltoreq.1 is added (superposed) by the adder 83 in the same manner as in the first embodiment. Then, the video signal output from the OSD processing unit 8 ′ and added with the OSD display is displayed on the display panel 10. In this example as well, the microcomputer 20 operates the television receiver together with the OSD data memory 21 for storing the data necessary for OSD display (OSD data) and the position information thereof, including characters and graphics. The light control signal such as an infrared ray emitted from the remote controller (remote controller) 30 is received by the remote controller light receiving unit 22 and inputted, and predetermined control is performed as in the above (Example 1). In this other embodiment (Example 2), as apparent from the figure, the number of components increases. However, only the normal frame rate conversion unit is used as the frame rate conversion unit 9 ′. Therefore, the frame rate conversion unit can be constructed at a relatively low cost, so that it is possible to obtain the advantage of being more economically preferable.

In the first embodiment shown in FIG. 1 described above, a motion-compensated frame rate conversion (normal frame rate conversion) using a motion vector is performed on an image in which, for example, an OSD image that is a still image is combined with a background moving image. ), Noise occurs in the OSD image boundary part, and in the case of a halftone OSD image, the back side image seen through the OSD part and the part where the OSD intersects, noise is generated in the OSD image area. Repeat conversion (repeat frame rate conversion) for repeating the same frame is performed without performing frame rate conversion. This technique is particularly effective when the boundary between the background moving image and the inserted still image OSD image is clear.
However, for example, as shown in FIG. 6, in an image in which a moving telop (hereinafter referred to as “motion telop”) 861 such as a character character is added to a moving image 901 in the background video 851, for example, For example, when the still image volume display OSD image 871 is synthesized on the receiver side so as to partially overlap, applying the first embodiment in which repeat conversion is performed on the OSD image area applies the volume display OSD image 871. Separate frame rate conversion processing is performed for each character of the motion telop 861 inside and each character of the motion telop 861 outside the volume display OSD image 871. Then, in the portion where the volume display OSD image 871 of the motion telop 861 overlaps with the repeat frame rate conversion, motion blur that the outline of the moving telop character is perceived blurring or the motion of the telop character is blurred, Since the motion compensation frame rate conversion is performed on the portion outside the volume OSD 871, the above phenomenon does not occur, and as a result, different processing is performed partially in one character, which makes it very unsightly. .
A third embodiment that solves this problem will be described below with reference to FIGS. FIG. 7 is a block diagram illustrating the overall configuration of the television receiver according to the third embodiment. FIG. 8 is a flowchart showing an embodiment for reducing image quality degradation of a motion telop. FIG. 9 is a flowchart showing another embodiment for reducing image quality deterioration of a motion telop. In FIG. 7, elements having the same functions as those in FIG. 1 are denoted by the same reference numerals, and repeated descriptions of elements once described are omitted. 8 and 9, frame rate conversion is abbreviated as FRC conversion.

  First, the television receiver according to the present embodiment will be described with reference to FIG. 7 focusing only on the differences from the configuration of the first embodiment.

  In FIG. 7, the motion telop detection unit 25 detects a motion telop included in a video signal including a moving image input to the image quality correction processing unit via the tuner 2, for example. Here, the video signal after scaling is input to the motion telop detection unit 25, but the present invention is not limited to this. For example, the video signal switched by the switching unit 4 may be input, and the video signal after OSD processing input to the frame rate conversion unit 9 may be input, although the accuracy is reduced. Good. The motion telop detection unit 25 detects a motion telop included in the input video signal. When a motion telop is detected, the motion telop detection unit 25 detects a motion telop area position in an image frame including the motion telop. And the motion telop area position information are notified to the microcomputer 20A. The microcomputer 20A controls each element in the same manner as in the first embodiment and receives motion telop detection information and position information from the motion telop detection unit 25. For example, in the frame rate conversion control process for the frame rate conversion unit 9, A frame rate conversion control process as will be described later with reference to FIG. 8 is performed. That is, when the microcomputer 20A receives the motion telop detection information and the position information from the motion telop detection unit 25, the microcomputer 20A determines whether the OSD image position overlaps from the position information of the motion telop, and if there is a motion telop overlapping the OSD image, Controls repeat conversion for the entire screen.

  Next, the frame rate conversion control process of the microcomputer 20A according to the present embodiment will be described with reference to FIG.

  In FIG. 8, when the microcomputer 20A starts the frame rate conversion control process, first, in step 1 (hereinafter, step is abbreviated as “S”), whether or not the target frame image to be frame rate converted includes an OSD image display. judge. Since the microcomputer 20A controls the OSD image insertion as already described in the section of the first embodiment, it can determine whether the OSD image display is included. If there is no OSD image display in S1, the process proceeds to S4. In S4, motion compensation type frame rate conversion is performed, and the process returns to S1 to continue the frame rate conversion. If the OSD image display is included in S1, the microcomputer 20A proceeds to S2, and from the motion telop detection information detected by the motion telop detection unit 25 and the position information of the motion telop area, the motion telop overlapping the OSD image. Determine if there is any. If there is no motion telop overlapping with the OSD image in S2, the process proceeds to S5, where the OSD image portion is subjected to repeat conversion without performing motion compensation type frame rate conversion, and the motion compensation type is applied to the background moving image. The frame rate conversion is performed, and the process returns to S1 to continue the frame rate conversion. If it is determined in S2 that there is a motion telop overlapping with the OSD image in S2, the microcomputer 20A proceeds to S3, performs repeat conversion on the entire screen, returns to S1, and continues frame rate conversion.

As described above, in this embodiment, if there is a motion telop that overlaps with the OSD image, only the OSD image portion is not subjected to repeat conversion, and repeat conversion is performed on the entire screen, so that deterioration of the image quality of the OSD image can be prevented. At the same time, it is possible to eliminate problems caused by performing separate frame rate conversion processing on the portion within the OSD area and the portion outside the OSD in the motion telop overlapping the OSD image. Of course, this may cause motion unnaturalness (jerkiness, judder) due to repeat frame rate conversion in the video, but compared to the unsightly such as partial motion blur and rattling of motion telop, It is considered to be within an acceptable range.
The above-described embodiment is an example of a frame rate conversion control process that eliminates partial motion blur and rattling of a motion telop that overlaps an OSD image on the premise that image quality deterioration of the OSD image is prevented. Next, another embodiment that prioritizes smooth motion of moving images and eliminates partial motion blur and rattling of motion telops that overlap OSD images will be described with reference to FIG. Note that, in FIG. 9, steps that perform the same processing as in FIG. 8 are indicated by steps having the same reference numerals, and redundant description thereof is omitted.

  Another frame rate conversion control processing example shown in FIG. 9 differs from FIG. 8 only in the processing of S3B. That is, if it is determined in S2 that there is a motion telop that overlaps the OSD image in S2, the microcomputer 20A proceeds to S3B, performs motion compensation type frame rate conversion on the entire screen, and returns to S1 to continue frame rate conversion. To do. Thereby, even if there is a motion telop that overlaps with the OSD image, a smooth motion can be realized with respect to the motion telop. Of course, according to this processing example, image quality degradation occurs at the boundary of the OSD image. However, this process is effective when it is desired to prioritize the movement of the motion telop. This is particularly effective when the motion telop moves quickly.

  It is also possible to determine, based on the motion speed of the motion telop, whether repeat transform is used for the entire screen or motion compensated FRC transform is used for the entire screen when an overlap between the motion telop and OSD is detected. . For example, when the microcomputer 20A detects the motion speed of the motion telop from the motion telop detection information and / or motion telop area position information detected by the motion telop detection 25 in FIG. 7, and the motion speed is smaller than a predetermined value, The microcomputer 20A controls the frame rate conversion unit 9 so that repeat conversion is performed on the entire screen and the motion compensation FRC conversion is performed on the entire screen when the motion speed is higher than a predetermined value. As a result, it is possible to provide a user-friendly video adapted to the motion of the motion telop.

  Note that the generation of noise can be suppressed even if the frame rate conversion (repeat frame rate conversion) by repeat shown in the above embodiment is replaced with the frame rate conversion (linear frame rate conversion) by linear interpolation (average interpolation). Is clear.

It is a block diagram which shows schematic structure of the television receiver which becomes one embodiment of this invention. It is explanatory drawing explaining the frame rate conversion operation | movement after the OSD process in the said television receiver. It is a figure which shows an example of the video display containing OSD display in the said television receiver. It is a block diagram which shows schematic structure of the television receiver which becomes other embodiment of this invention. It is a figure which shows an example of operation | movement of the normal frame rate conversion part 91 in this invention. It is a figure which shows the frame image containing the motion telop which overlaps with an OSD image. FIG. 10 is a block diagram illustrating a schematic configuration of a television receiver according to a third embodiment. It is a flowchart which shows one Example which reduces the image quality degradation of a motion telop. It is a flowchart which shows another Example which reduces the image quality degradation of a motion telop.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Antenna 2 ... Tuner 3 ... External video input terminal 4 ... Switching part 5 ... I / P conversion part 6 ... Scaling part 7 ... Image quality correction part 8, 8 '... OSD process part 9, 9' ... Frame rate conversion part 91 ... Normal frame rate conversion unit 92 ... OSD frame rate conversion unit 93 ... Switching unit 10 ... Display panel 20, 20A ... Microcomputer 23 ... Synchronization detection unit 25 ... Motion telop detection unit

Claims (3)

A television receiver that interpolates a video signal including a moving image to which a motion telop is added and displays a video together with an OSD image,
An image quality correction unit for correcting the image quality of the video signal including the input video;
An OSD image insertion unit that inserts an OSD image into a video signal including a moving image from the image quality correction unit;
A frame rate conversion unit that performs frame rate conversion of any of a plurality of conversion methods on a video signal including a moving image in which an OSD image is inserted, output from the OSD image insertion unit;
A display unit for displaying a video signal output from the frame rate conversion unit;
A motion telop detection unit for detecting a motion telop area included in the video signal including the input video;
Using the position where the OSD image is inserted and the motion telop area detected by the motion telop detection unit, the frame rate conversion unit performs frame rate conversion by any one of the plurality of conversion methods. A control unit for controlling,
The plurality of conversion methods are:
Motion compensated frame rate conversion that detects a motion vector from a plurality of frames included in a video signal, creates an interpolated frame based on the motion vector and performs frame rate conversion, and repeat frame rate that repeats the same frame and performs frame rate conversion It is linear frame rate conversion that performs frame rate conversion by conversion and linear interpolation.
The frame rate conversion unit uses any one of the motion compensated frame rate conversion, the repeat frame rate conversion, and the linear frame rate conversion to the video signal into which the OSD image output from the OSD image insertion unit is inserted. For frame rate conversion,
When the motion telop area does not overlap with the OSD image position, the control unit performs the repeat frame rate conversion or the linear frame rate conversion on the OSD image, and the motion telop area moves to the OSD image position. A television receiver that controls the frame rate conversion unit to perform the repeat frame rate conversion or the linear frame rate conversion on one frame screen . A television receiver that interpolates a video signal including a moving image to which a motion telop is added and displays a video together with an OSD image,
An image quality correction unit for correcting the image quality of the video signal including the input video;
An OSD image insertion unit that inserts an OSD image into a video signal including a moving image from the image quality correction unit;
A frame rate conversion unit that performs frame rate conversion of any of a plurality of conversion methods on a video signal including a moving image in which an OSD image is inserted, output from the OSD image insertion unit;
A display unit for displaying a video signal output from the frame rate conversion unit;
A motion telop detection unit for detecting a motion telop area included in the video signal including the input video;
Using the position where the OSD image is inserted and the motion telop area detected by the motion telop detection unit, the frame rate conversion unit performs frame rate conversion by any one of the plurality of conversion methods. A control unit for controlling,
The plurality of conversion methods are:
Motion compensated frame rate conversion that detects a motion vector from a plurality of frames included in a video signal, creates an interpolated frame based on the motion vector and performs frame rate conversion, and repeat frame rate that repeats the same frame and performs frame rate conversion It is linear frame rate conversion that performs frame rate conversion by conversion and linear interpolation.
The frame rate conversion unit uses any one of the motion compensated frame rate conversion, the repeat frame rate conversion, and the linear frame rate conversion to the video signal into which the OSD image output from the OSD image insertion unit is inserted. For frame rate conversion,
When the motion telop area does not overlap the OSD image position, the control unit performs repeat frame rate conversion or linear frame rate conversion on the OSD image, and the motion telop area overlaps the OSD image position. In this case, the television receiver controls the frame rate conversion unit to perform motion compensation frame rate conversion on one frame screen . The television receiver according to claim 1 or 2,
Using the area detected by the motion telop detection unit, the motion speed of the motion telop is detected, and when the motion speed is smaller than a predetermined value, repeat frame rate conversion is performed for one frame screen, and the motion speed is predetermined. A television receiver comprising a control unit that controls a frame rate conversion unit so as to perform motion compensation frame rate conversion for one frame screen when the value is larger than the value.

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