JP2010266663A - Image display processing apparatus and liquid crystal display device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To identify a still image using one decoder circuit, without fail, and to attain reduction in the required memory capacity, when improving response rate by performing overdrive processing with respect to displayed image data. <P>SOLUTION: An image display processor includes an encoder circuit for encoding current image data; a storage means for storing the image data encoded in the encoder circuit; a still image identification threshold selecting circuit which determines threshold, based on a transition of an encoded predictive value stored in the storage means; and a decoder circuit for decoding the encoded image data stored in the storage means. The processing performs still image identification, by using the still image identification threshold selected by the still image identification threshold selecting circuit, the current image data, and the decoded image data decoded in the decoding circuit, and performs the overdrive processing by controlling turning on/off of the overdriving operation. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to an image display process and a liquid crystal display device that significantly reduce the memory capacity of a frame memory required for overdrive drive processing, prevent unnecessary overdrive drive processing, and obtain a good image. .

An image data processing apparatus, an image data processing method, and an image data processing method for accurately controlling a response speed of a liquid crystal in response to a change in luminance of a moving image without increasing a memory capacity of an image data processing unit and causing deterioration in image quality, As for liquid crystal display devices, there are the following conventional examples.
That is, according to Patent Document 1, the current image data of a certain pixel received as image data is encoded, the encoded image data is decoded by the current image decoding circuit, and the encoded image data is transmitted for one frame period. The change amount data is calculated from the stored encoded image data of the previous frame by the image data obtained by decoding the one-frame delayed image data decoding circuit, and the display data of the previous frame is generated from the calculated change amount. . By generating the corrected image data based on the generated display data and the current image data, it is possible to cope with the luminance change of the moving image surface without increasing the memory capacity of the image data processing unit and without causing deterioration of the image quality. An image data processing device, an image data processing method, and a liquid crystal display device that accurately control the response speed of the liquid crystal are described.

JP 2004-163842 A

However, as in the above-described device, in order to calculate the variation data of the image data, the current image decoding circuit and the one-frame delayed image data decoding circuit are required, and two types of decoding circuits having the same function are required. As the compression rate is improved, the circuit scale of the decoding circuit increases and the power consumption increases.
The present invention has been made in view of such a situation, and aims to greatly reduce the memory capacity and to delete a redundant decoding circuit so that the circuit scale and power consumption can be reduced. .

  The present invention provides means for solving these problems, and the image display processing device according to each of the claims constitutes the following technical means.

  According to a first aspect of the image display processing apparatus of the present invention, in the image display processing including overdrive drive processing means capable of ON / OFF control of the overdrive drive processing for the display image data, the current image data A coding circuit that encodes the image data, a storage unit that stores the image data encoded by the coding circuit, and a threshold selection circuit for determining a still image that determines a threshold value based on a transition of the encoded prediction value stored in the storage unit A decoding circuit for decoding the encoded image data stored in the storage means, a still image determination threshold selected from the still image determination threshold selection circuit, the current image data, and the decoding circuit Image data correction circuit that performs still image determination with the decoded image data, performs overdrive drive processing ON / OFF control, and performs overdrive drive processing It is set to the image display processing apparatus, characterized in that.

  In the second aspect of the image display processing device according to claim 2, the image display processing device according to claim 1, wherein the image data is only R data in RGB format. According to a third aspect of the image display processing device, the image data is only G data in RGB format, and the image display processing device according to claim 4, In the fourth aspect, the image display processing apparatus according to claim 1, wherein the image data is only B data in RGB format. In the fifth aspect of the image display processing apparatus according to claim 5, The image display processing device according to claim 1, wherein the image data is any data in RGB format, and the image display processing device according to claim 6. In a sixth aspect, and the image display processing apparatus according to claim 1, wherein the image data is all data in the RGB format.

  In a seventh aspect of the image display processing device according to claim 7, the image display processing device according to claim 1, wherein the image data is only Y data in YUV format. According to an eighth aspect of the image display processing apparatus of the present invention, the image display processing apparatus according to claim 1, wherein the image data is all data in a YUV format.

  Furthermore, according to a ninth aspect of the image display processing apparatus of the present invention, the storage means for storing the image data has a single memory configuration. The image according to any one of claims 1 to 8, wherein in the tenth aspect of the image display processing apparatus, the storage means for storing the image data has a two-memory configuration. 11. An eleventh aspect of the image display processing device according to claim 11 as a display processing device comprises a liquid crystal display panel and an image processing device for outputting display data to the liquid crystal display panel. A liquid crystal display device using the image display processing device described in any one of the above.

  According to the image display processing device of the first aspect of the present invention, the encoding circuit for encoding the current image data, the storage means for storing the image data encoded by the encoding circuit, A still image determination threshold value selection circuit for determining a threshold value by a transition of the encoded prediction value stored in the storage means, a decoding circuit for decoding the encoded image data stored in the storage means, and the still image determination value By performing still image determination using the still image determination threshold value selected from the threshold selection circuit, the current image data, and the decoded image data decoded by the decoding circuit, and controlling the overdrive driving process ON / OFF, By significantly reducing the memory capacity of the frame memory required for the overdrive driving process, it is possible to perform the optimum still image determination with one decoding circuit, thereby eliminating unnecessary overdriving. It is possible to prevent blanking driving process.

  According to the image display processing device of the second to sixth aspects according to claims 2 to 6 of the present invention or the image processing apparatus of the seventh and eighth aspects of claims 7 and 8, image data is stored. Whether the image data is in RGB format or YUV format, still image determination can be performed reliably and accurately. According to the ninth and tenth image processing apparatuses according to claims 9 and 10, The storage means for storing data can be aggregated into one or two, and the eleventh aspect of the image processing apparatus according to the eleventh aspect can be suitably applied to image display processing of a liquid crystal display panel.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a block diagram for explaining an image display processing apparatus having a frame memory as one memory structure according to the present invention. FIG. 2 is a block diagram for explaining an image display processing apparatus according to the present invention in which a frame memory has two memory configurations.

  With the recent increase in image processing unit data due to high definition of liquid crystal panels, there has been a problem of increasing the capacity of the frame memory. As a countermeasure, data compression by data thinning / encoding processing has been proposed. Yes. In addition, overdrive drive processing is accurate even if the input image data is a still image, but it is erroneously determined to be a moving image, because unnecessary overdrive drive is processed and the image breaks down. It is necessary to obtain a correct image.

Here, as an example of the encoding process, a DPCM code that is a differential encoding method will be introduced.
In the compression method by DPCM that compresses and encodes image data, the error between the accuracy determination flag and the adjacent image data is encoded by utilizing the strong correlation between the adjacent image data. As an encoded prediction value that is encoded data, there are an accuracy determination flag and compressed data. The accuracy determination flag is set when the error between the previous image data and the current image data is large (for example, the accuracy determination flag is set to “1”). If the error is within the accuracy range, the accuracy determination flag is not set ( For example, the accuracy determination flag is set to “0”). When the current accuracy determination flag is set, the compressed data is bit-shifted and rounded regardless of the state of the previous accuracy determination flag. When the previous accuracy determination flag is set and the current accuracy determination flag is not set, the previous image When the previous accuracy determination flag and the current accuracy determination flag are not raised, the difference data from the previous image data is encoded as it is.

  In the following, the transition of the encoded prediction value is monitored, still image determination is performed, unnecessary overdrive driving processing is prevented, and frame data is encoded and data compressed to greatly reduce the frame memory capacity. Embodiments 1 to 5 will be described.

(Embodiment 1)
Embodiment 1 of an image display processing apparatus according to the present invention will be described below with reference to the drawings.
FIG. 1 is a block diagram for explaining an image display processing apparatus according to the present embodiment.
As shown in FIG. 1, in the image display processing apparatus of the present embodiment, the data amount of the current image data 111 is significantly compressed by the encoding circuit 101 that encodes the current image data 111. Here, encoding is performed using a DPCM code, which is the differential encoding method described above, as an example of an encoding method. Since the encoded encoded image data 112 is stored in the frame memory 102 after the image data is compressed, the frame memory capacity can be greatly reduced.

The frame memory 102 reads the encoded image data 113 one frame before, which is encoded image data delayed by one frame from the current image data 111, to the still image determination threshold selection circuit 103 and the decoding circuit 104. Is done. The still image determination threshold selection circuit 103 monitors the transition of the accuracy determination flag of the encoded prediction value and selects the still image determination threshold 114. Regardless of the previous accuracy determination flag, if the current accuracy determination flag is set, the encoding error is large, so the still image determination threshold is set to a large value. When the previous accuracy determination flag is set and the current accuracy determination flag is not set, the encoding error is small, so the still image determination threshold 114 is set to a small value. If neither the previous accuracy determination flag nor the current accuracy determination flag is set, there is no encoding error, and the still image determination threshold 114 is set to zero. When the current image data 111 and the decoded image data 115 decoded from the decoding circuit 104 are compared, and the difference data is smaller than the still image determination threshold value 114 selected by the still image determination threshold selection circuit 103 Is determined as a still image, and the overdrive driving process of the image data correction circuit 105 is not performed.
As described above, the difference data between the current image data 111 and the decoded image data 115 decoded from the decoding circuit 104, and the still image determination threshold value selected corresponding to the transition of the accuracy determination flag of the encoded prediction value. 114, the still image can be reliably determined by only one decoding circuit 104. When the difference data is larger than the still image determination threshold 114, it is determined as a moving image and the image data correction circuit By performing the overdrive driving process 105, the memory capacity of the frame memory required for the overdrive driving process can be greatly reduced, and unnecessary overdrive driving processes can be prevented.

(Embodiment 2)
In FIG. 1, when the image data is in the RGB format, the current image data 111, the encoded image data 112, the encoded image data 113 of the previous frame, and the decoded image data 115, among the image data in the RGB format, Any one of R data (corresponding to the second aspect), G data (corresponding to the third aspect), or B data (corresponding to the fourth aspect) may be selected. Further, any combination of R data, G data, and B data (corresponding to the fifth aspect), or all data (corresponding to the sixth aspect) may be used.

(Embodiment 3)
On the other hand, when the image data is in the YUV format, similarly, in FIG. 1, the current image data 111, the encoded image data 112, the encoded image data 113 one frame before, and the decoded image data 115 are converted into the YUV format. Of the image data, only Y data (corresponding to the seventh aspect) or all data (corresponding to the eighth aspect) may be used.

(Embodiment 4)
In FIG. 1, the frame memory 102 is a single memory having both functions of reading and writing data, and is a memory that can simultaneously read and write addresses other than the same address, and stores image data. The means is composed of one memory (corresponding to the ninth aspect).

(Embodiment 5)
On the other hand, in FIG. 2, two frame memories 202 and 206 are provided, and each of the memories 202 and 206 is a memory having both functions of reading and writing data. Are controlled in units of frames (corresponding to the tenth aspect).

(Embodiment 6)
In each of the above embodiments, the output of the image processing device is output as display data to the liquid crystal display panel, and constitutes the liquid crystal display device (corresponding to the tenth aspect).

101, 201: Coding circuits 102, 202, 206: Frame memory 103, 203: Threshold selection circuit for still image determination 104, 204: Decoding circuit 105, 205: Image data correction circuit 111, 211: Current image data 112, 212: Encoded image data 113, 213: Encoded image data one frame before 114, 214: Threshold value for still image determination 115, 215: Decoded image data

Claims (11)

  In an image display process provided with an overdrive drive processing means capable of controlling ON / OFF of an overdrive drive process for display image data, an encoding circuit for encoding current image data, and an encoding circuit encoded by the encoding circuit Storage means for storing image data, still image determination threshold value selection circuit for determining a threshold value based on transitions of encoded prediction values stored in the storage means, and decoding of encoded image data stored in the storage means Comparing the difference data between the current image data and the decoded image data decoded by the decoding circuit with a still image determination threshold value selected from the still image determination threshold value selection circuit. Equipped with an image data correction circuit that performs still image determination, overdrive drive processing ON / OFF control, and overdrive drive processing The image display processing apparatus.   2. The image display processing apparatus according to claim 1, wherein the image data is only R data in RGB format.   The image display processing apparatus according to claim 1, wherein the image data is only G data in RGB format.   2. The image display processing apparatus according to claim 1, wherein the image data is only B data in RGB format.   2. The image display processing apparatus according to claim 1, wherein the image data is any data in an RGB format.   2. The image display processing apparatus according to claim 1, wherein the image data is all data in RGB format.   2. The image display processing apparatus according to claim 1, wherein the image data is only Y data in YUV format.   2. The image display processing apparatus according to claim 1, wherein the image data is all data in a YUV format.   9. The image display processing apparatus according to claim 1, wherein the storage means for storing the image data has a single memory configuration.   9. The image display processing apparatus according to claim 1, wherein the storage means for storing the image data has a two-memory configuration.   A liquid crystal display device comprising: a liquid crystal display panel; and an image processing device that outputs display data to the liquid crystal display panel, wherein the image display processing device according to claim 1 is used.

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