JP2009260539A - Image processing apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To perform image processing that obtains the effect of improving a moving image blur even when displaying OSD signals, and does not generate unnatural interpolation frame signals without the need of an OSD signal generator in a special configuration for generating the OSD signals of a high frame rate. <P>SOLUTION: A frame generation circuit 12 generates the interpolation frame signal of an input video signal 11 by a well-known configuration. A synthesis circuit 131 synthesizes the input video signal 11 and the OSD signal output from the OSD signal generator 14. A synthesis circuit 132 synthesizes the interpolation frame signal generated by the frame generation circuit 12 and the OSD signal output from the OSD signal generator 14. A selector 15 sequentially selects the respective output synthetic signals of the synthesis circuits 131 and 132 within one frame cycle and outputs an output signal 16 with which double speed processing is performed. In the frame generation circuit 12, the interpolation frame signal is generated only on the basis of the input video signal 11 regardless of the OSD signal. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an image processing apparatus, and more particularly to an OSD (On Screen Display) insertion method at the time of outputting a high frame rate.

  A hold-type display device typified by a liquid crystal display device continues to hold an image of the previous frame until writing for each frame is performed. Due to this characteristic, it is known that a hold-type display device causes motion blur. That is, while the hold-type display device updates the frame image only at the transition of the frame, the human eye causes the line of sight to follow the moving image smoothly, so that the difference is recognized as moving image blur. .

  One method of reducing the above-mentioned motion blur is to increase the frame rate and shorten the frame interval. In order to increase the frame rate of the output signal relative to the frame rate of the input signal, it is necessary to generate a new frame. As a typical method, a method of creating an interpolation image using motion compensation is representative (see, for example, Patent Document 1). This method is a method of detecting a motion vector between a previous frame image and a subsequent frame image of an input image signal to be interpolated, and generating a new interpolation frame from previous and subsequent frame images based on the detected motion vector. .

JP 2006-331136 A

  Incidentally, in the liquid crystal display device, an OSD signal such as a menu screen is displayed on the display screen by the OSD signal generator. However, in the liquid crystal display device of Patent Document 1, there is a reference about the display of the OSD signal. Absent.

  The present invention has been made in view of the above points. An OSD signal generator having a special configuration that can obtain an effect of improving motion blur even when an OSD signal is displayed and that generates an OSD signal having a high frame rate. It is an object of the present invention to provide an image processing apparatus that does not need to generate an unnatural interpolation frame signal.

  In order to achieve the above object, the present invention detects a motion vector of an input video signal and, based on the detected motion vector, (N−1) interpolation frame signals, which are interpolation signals between frames of the input video signal. (N is a natural number of 2 or more) Interpolated frame generating means to be generated, image signal generating means for generating an image signal of video information different from the input video signal, input video signal and image signal output from the image signal generating means And (N-1) interpolated frame signals generated by the interpolated frame generating means and each of the interpolated frame signals output from the image signal generating means. A second synthesizing unit that synthesizes the image signal to generate a composite signal group including (N−1) second composite signals, a first composite signal, and (N−1) composite signals; Of the input video signal Sequentially selects in a frame period, characterized by having a selection means frame rate to generate an output signal which is N times the input video signal.

  In this invention, the interpolation frame generation means generates an interpolation frame signal based only on the input video signal, and synthesizes an image signal of video information different from the input video signal with the interpolation frame signal, so that an unnatural interpolation frame is generated. Signal generation can be prevented. Further, in the present invention, the image signal of the video information different from the input video signal and the interpolated frame signal are synthesized on the input side of the selection means for making the frame rate N times the input video signal. The frame rate of the image signal output by the signal generating means can be made the same as the frame rate of the input video signal that is 1 / N times the frame rate of the output signal.

According to the present invention, an image signal having a special configuration capable of obtaining an effect of improving moving image blur and generating an image signal with a high frame rate even when an image signal of video information different from the input video signal is displayed. Image processing without generating an unnatural interpolation frame signal can be performed without the need for a generator.

  Embodiments of the present invention will be described below in detail with reference to the drawings.

  FIG. 1 shows a block diagram of a first embodiment of an image processing apparatus according to the present invention. As shown in the figure, it is an example of an image processing apparatus having a function of generating an interpolation frame. This image processing apparatus is an image processing apparatus when the OSD signal generator 33 displays an OSD signal such as a menu screen on the display screen. In FIG. 1, an input video signal 31 having a frequency of 60 Hz is supplied to a synthesis circuit 32, where it is synthesized with an OSD signal such as a menu screen from the OSD signal generator 33 to become a synthesized signal. The combined signal output from the combining circuit 32 is supplied to the frame generation circuit 34 and the selector 35, respectively.

  The frequency 60 Hz is a field frequency when the input video signal 31 is an NTSC video signal. However, when this image processing device is applied to a hold type display device, it is a display frequency for one screen. In this specification, it is referred to as a frame frequency (hereinafter the same).

  As described in Patent Document 1, the frame synthesis circuit 34 delays an input composite signal, and outputs one or two or more delayed video signals different from each other by m frames (m is a natural number) with respect to the input composite signal. First delay means to obtain, correlation detection means for detecting the correlation between the input composite signal and the delayed video signal, and outputting the correlation detection result, and a plurality of motion vector candidates obtained from the correlation detection result Among them, based on the reference motion vector, a motion vector detection means for detecting a motion vector candidate in one direction as a motion vector, and the detected motion vector is delayed by one frame and supplied to the motion vector detection means as the reference motion vector. And a second delay means, and a frame that will be between the input synthesized signal and the one-frame delayed synthesized signal in accordance with the detected motion vector. Measuring to, and an interpolation frame circuit for outputting an interpolation frame signal.

  The selector 35 alternately selects the synthesized signal output from the synthesizing circuit 32 and the interpolated frame signal output from the frame generating circuit 34 at a frequency higher than that of the original input video signal 31, and has a frame frequency of 120 Hz. An output signal 36 subjected to double speed processing is output. The output signal 36 is a signal obtained by alternately synthesizing the synthesized signal of the input video signal 31 and the OSD signal and the interpolated frame signal in time series.

  However, since the frame generation circuit 34 in this image processing apparatus detects a motion vector from the previous and subsequent frames and generates an interpolation frame based on the motion vector, the detection accuracy of the motion vector greatly affects the quality of the interpolation frame. In particular, a complicated video in which a plurality of different motions exist on the same screen is difficult to detect an accurate motion vector, and an unnatural interpolation frame may be generated.

  One example is a video when a television menu screen is displayed. Most TV menu screens are displayed on the screen in a stationary state regardless of the input video signal. When the menu screen is displayed with a moving image, the input image and the menu screen move differently.

  For example, in the case of an image signal in which the movement of the ball from left to right can be clearly seen in three consecutive frames as shown by 61, 62, 63 in FIG. It is not difficult to correctly detect a motion vector by this method. However, as shown in FIG. 6B, when the ball 62 is hidden by the menu screen 65, it is difficult to correctly detect the motion vector by the method described in Patent Document 1. If an accurate motion vector is not detected, an unnatural interpolation frame is generated.

  That is, in this image processing apparatus, when the OSD signal is displayed, the input video signal 31 is different from the motion of the OSD signal and the motion is difficult to predict, for example, a scene with much motion as shown in FIG. In the case of a video in which a menu or the like is displayed as the OSD image 72 in the video 71 of FIG. 5, since it is difficult to accurately detect the motion vector in the frame generation circuit 34, an unnatural interpolation frame signal may be generated. Is expensive.

  Therefore, as a method for preventing an unnatural interpolation frame signal from being generated when the OSD signal is displayed, an interpolation frame signal based on a motion vector is not generated during OSD display, that is, a method for generating an interpolation frame similar to the input signal is available. Conceivable.

  FIG. 2 is a block diagram showing an example of an image processing apparatus according to the second embodiment of the image processing apparatus of the present invention, which is based on a method for generating an interpolation frame similar to an input signal. In the figure, the same components as those in FIG. 1 are denoted by the same reference numerals.

  The image processing apparatus shown in FIG. 2 is generated by the frame generation circuit 34 from the synthesized signal obtained by synthesizing the input video signal 31 and the OSD signal by the synthesizing circuit 32 and the synthesized signal, similarly to the image processing apparatus shown in FIG. A total of two signals of the interpolated frame signal are prepared.

  The selector 41 selects one of the synthesized signal obtained by the synthesis circuit 32 and the interpolated frame signal generated by the frame generation circuit 34 and inputs the selected signal to the selector 42. The selector 42 sequentially selects the composite signal obtained by the synthesis circuit 32 and the signal selected by the selector 41 within one frame period, and outputs an output signal 43 having a frame frequency of 120 Hz.

  Here, when the OSD signal such as the menu screen is not displayed, the OSD signal generator 33 does not output the OSD signal, so the synthesized signal generated by the synthesizing circuit 32 is equal to the input video signal 31. At this time, the selector 41 selects the interpolated frame signal generated by the frame generation circuit 34. On the other hand, when displaying the OSD signal, the selector 41 selects a composite signal of the OSD signal obtained by the composite circuit 32 and the input video signal 31.

  According to this image processing apparatus, since the interpolation frame based on the motion vector is not generated when the OSD signal is displayed, an unnatural interpolation frame signal when the OSD signal is displayed is not generated.

  FIG. 3 is a block diagram of another example of the image processing apparatus according to the third embodiment of the present invention that does not generate an unnatural interpolation frame when the OSD is displayed. is there. In the figure, an input video signal 51 having a frame frequency of 60 Hz is supplied to a frame generation circuit 52 having a configuration described in Patent Document 1 to be an interpolated frame signal. The selector 53 sequentially selects the interpolated frame signal generated by the frame generation circuit 52 and the input video signal 51 within one frame period, and outputs a signal having a frame frequency of 120 Hz. The combining circuit 54 combines the signal output from the selector 53 and the OSD signal output from the OSD signal generator 55, and outputs the combined signal as an output signal 56.

  According to this image processing apparatus, since the frame generation circuit 52 generates an interpolation frame signal based only on the input video signal 51 regardless of the OSD signal, an unnatural interpolation frame when the OSD signal described above is displayed. It does not produce a signal.

  FIG. 4 is a block diagram showing a fourth embodiment of the image processing apparatus according to the present invention. The image processing apparatus 10 according to the present embodiment is a double speed processing apparatus that generates an output signal 16 having a frame frequency of 120 Hz with respect to an input video signal 11 having a frame frequency of 60 Hz, and includes a frame generation circuit 12, synthesis circuits 131 and 132, and an OSD signal. It comprises a generator 14 and a selector 15. The frame generation circuit 12 is a circuit that generates an interpolated frame signal that is an interpolated signal between frames of the input video signal 11 with the configuration described in Patent Document 1. The OSD signal generator 14 generates an OSD signal of different image information different from the image information of the input video signal 11.

  Next, the operation of the present embodiment will be described. The first synthesis circuit 131 synthesizes the input video signal 11 and the OSD signal output from the OSD signal generator 14, and supplies the obtained first synthesis signal to the selector 15. The second synthesis circuit 132 synthesizes the interpolated frame signal generated by the frame generation circuit 12 and the OSD signal output from the OSD signal generator 14, and supplies the obtained second synthesis signal to the selector 15. To do.

  Here, since the input video signal 11 and the frame interpolation signal each have a frame frequency of 60 Hz, these signals and the OSD signal synthesized by the first and second synthesis circuits 131 and 132 are also 60 Hz. A generator that generates an existing 60 Hz OSD signal can be used.

  The selector 15 sequentially selects the first synthesized signal and the second synthesized signal within one frame period, and the first synthesized signal and the second synthesized signal are synthesized in time series. A signal subjected to double speed processing at a frame frequency of 120 Hz is output as an output signal 16. Here, in this image processing apparatus 10, the OSD signal and the input signal are synthesized by the second synthesis circuit 132 subsequent to the frame generation circuit 12. Therefore, the frame generation circuit 12 converts the OSD signal into the OSD signal. Regardless, since the interpolated frame signal is generated based only on the input video signal 11, the above-described unnatural interpolated frame signal is not generated when the OSD signal is displayed, and the moving image is blurred even when the OSD signal is displayed. The improvement effect can be obtained.

  Next, a fifth embodiment of the present invention will be described. FIG. 5 shows a block diagram of a fifth embodiment of an image processing apparatus according to the present invention. The image processing apparatus 20 according to the present embodiment is an N-times speed processing apparatus that generates an output signal 27 having a frame frequency α × NHz (N is a natural number of 2 or more) with respect to an input video signal 21 having a frame frequency αHz. The circuit 22 includes a remote controller (hereinafter referred to as a remote control device) 23, an OSD signal generator 24, a synthesis circuit 251, a synthesis circuit group 252, and a selector 26.

  The frame generation circuit 22 is a circuit that generates an interpolated frame signal group composed of (N−1) interpolated frame signals that are interpolated signals between frames of the input video signal 21 with the same configuration as that described in Patent Document 1. It is. The image processing apparatus 20 in FIG. 5 has the same configuration as that of the image processing apparatus 10 in FIG. 4 except for the remote controller 23 when α = 60 and N = 2. The OSD signal generator 24 includes a receiving unit that receives and analyzes the remote control signal.

  Next, the operation of the present embodiment will be described. The frame generation circuit 22 receives the input video signal 21 as an input, generates an interpolated frame signal group composed of (N−1) interpolated frame signals, and supplies it to the synthesis circuit group 252. On the other hand, in order to display a desired OSD such as a menu screen, the user operates the remote control device 23 to transmit a remote control signal of a predetermined code to the OSD signal generator 24. The OSD signal generator 24 receives and analyzes the remote control signal transmitted from the remote control device 23 by an internal reception unit, and generates an OSD signal having a frequency αHz and information content corresponding to the received remote control signal.

  The synthesizing circuit 251 synthesizes the input video signal 21 and the OSD signal output from the OSD signal generator 24 to generate a first synthesized signal, and supplies the first synthesized signal to the selector 26. At the same time, the synthesis circuit group 252 combines each of the (N−1) interpolation frame signals output from the frame generation circuit 22 and the OSD signal output from the OSD signal generator 24. (N−1) second synthesized signal groups are generated, and the second synthesized signal groups are supplied to the selector 26.

  The selector 26 sequentially selects a total of N (N frames) composed of the first composite signal and the second composite signal group within one frame period of the input video signal 21. By outputting, an output signal 27 having a frame frequency α × N (Hz) in which these synthesized signals are synthesized in time series is outputted.

  Here, in this image processing apparatus 20, since the OSD signal and the input signal are synthesized by the synthesis circuit group 252 at the subsequent stage of the frame generation circuit 22, the frame generation circuit 22 has no relation to the OSD signal. Since the interpolated frame signal is generated based only on the input video signal 21, the above-described unnatural interpolated frame signal is not generated when the OSD signal is displayed, and the motion blur is improved even when the OSD signal is displayed. An effect can be obtained. Further, in this image processing apparatus 20, the remote control device 23 can generate and display an OSD signal having desired information contents at a desired timing by the user.

  As described above, the fourth embodiment of the present invention and the fifth embodiment of the present invention can obtain the effect of improving the motion blur even when the image signal of the video information different from the input video signal is displayed. Compared with the second embodiment of the present invention, an effect of improving the motion blur can be expected.

  Also, in the fourth embodiment and the fifth embodiment of the present invention, the generation of an image signal having a special configuration that generates an image signal having a higher frame rate than the second embodiment of the present invention. The effect of not requiring a vessel can be expected.

1 is a block diagram of an image processing apparatus according to a first embodiment of the present invention. It is a block diagram of 2nd Embodiment of the image processing apparatus of this invention. It is a block diagram of 3rd Embodiment of the image processing apparatus of this invention. It is a block diagram of 4th Embodiment of the image processing apparatus of this invention. It is a block diagram of 5th Embodiment of the image processing apparatus of this invention. It is a figure explaining a problem when the signal which synthesize | combined the OSD signal and the video signal was input into the frame generation circuit. It is a figure which shows an example of the screen where an unnatural interpolation frame signal may arise.

Explanation of symbols

10, 20 Image processing device 11, 21 Input video signal 12, 22 Frame generation circuit 14, 24 OSD signal generator 15, 26 Selector 16, 27 Output signal 23 Remote controller (remote control device)
131, 132, 251 Synthesis circuit 252 Synthesis circuit group

Claims (2)

A motion vector of the input video signal is detected, and (N−1) interpolation frame signals (N is a natural number of 2 or more) are generated based on the detected motion vector. Interpolation frame generation means;
Image signal generating means for generating an image signal of video information different from the input video signal;
First combining means for combining the input video signal and the image signal output from the image signal generating means to generate a first combined signal;
Each of the (N−1) interpolated frame signals generated by the interpolated frame generating means and the image signals output from the image signal generating means are combined to give (N−1) second signals. Second combining means for generating a combined signal group composed of the combined signals of:
The first composite signal and the (N-1) composite signals are sequentially selected within one frame period of the input video signal, and an output signal having a frame rate N times the input video signal is obtained. An image processing apparatus comprising: selection means for generating. The image signal generation means includes
2. The image processing apparatus according to claim 1, further comprising a function of receiving and analyzing a remote control signal transmitted by a remote controller and generating the image signal of video information corresponding to a code of the received remote control signal.