200845729 HM-2006-0114-TW 22503twf.doc/n 九、發明說明： 【發明所屬之技術領域】 本發明是有關於-種影像處理的技術，且特 於一種適應性影像調整方法及使用其之影像處理，關 【先前技術】200845729 HM-2006-0114-TW 22503twf.doc/n IX. Description of the Invention: [Technical Field] The present invention relates to a technique for image processing, and is specific to an adaptive image adjustment method and using the same Image processing, off [previous technology]
影像處理(image processing)是把取得的數位影 影像處理軟體所提供的功能來做顏色、明暗度、^距， 各種影像晝面的改變，甚至是把兩張照片透過比較 操作程序來做合成。例如，可以用影像處理的一些功:、 如亮度與對比的變化就可以很快的把—張晴天的=片=_ 雨天的照#。甚至可_、剪_這些影像處理ς 程，把兩張照片做移花接木的處理效果，這樣就可以改變 影像原始的樣貌。因此，影像處理簡單地說就是改變= 析影像的資料。 為提南平面顯示器的晝面品質，需動態地調整影像， 例如以影像的党度作為判斷標準：對較暗的影像可以提高 對比，降低亮度，並可調低背光；對較亮的影像則降低g 比’ S周面党度’並可调局背光。 對於一些需要判斷影像亮度(brightness)之影像處理， 影像平均亮度是經常被使用到的一個判斷索引 index)。圖1績示為習知影像處理裝置之方塊圖。請參考 圖1，此影像處理裝置100包括亮度平均檢 測斋101、對比控制|§ (contrast controller) 102及亮度控制 器(brightness controller) 103。首先，將影像傳送至亮度平 5 200845729 HM-2006-0114-TW 22503twf.doc/n 均值檢測器101並藉由此亮度平均值檢測器1〇1得到此影 像之売度平均值。接著，根據所得到的亮度平均值做為判 斷索引，再經由對比控制器102以及亮度控制器1〇3據以 對上述之影像調整影像對比及亮度，並可對應調整背光， 以調高影像顯示品質。 —^而在很多情況下，平均亮度不足以區別不同影像内 ^之亮度的資訊。舉例來說，若有兩張影像如圖2A(影像 ( 免暗差異較小)及®2B(影像亮暗差異較大)所示，並且此兩 張影像的亮度平均值都是55，但是圖2B之影像相效於圖 2A之影像有較多“亮，，的成分。假設以平均亮度做為影像 ，整之基準時’會誤以為目2八及圖2β之影像的亮度成分 是-樣的’然而若制蝴的調整量進行影像調整，將會 造成其中-張影像的效果不佳，也會使影像不是過於太亮 或是太暗。因此，單靠影像亮度平均值的計算不僅益法區 別(distinguish)上述圖2A及圖2B之影像的差別，也會使影 像調整造成反效果。 ^ 【發明内容】 本考X月的目的就疋在提供一種適應性影像調整方法與 影像處理裝置，可對景彡像像素之灰階分布進行統計及分 斤’亚根據統計及分析之結果，進而將影像調整至最佳的 品質。 本發明提出-種適應性影像調整方法，此方法至少包 括下列步驟：提供-影像，此影像具有多個像素。統計上 迷像素的灰階分布。並且根據上述之灰階分布，找出一特 200845729 HM-2006-0114-TW 22503twf.doc/n 上述像素中’有-特定比例的像素的灰階是 接下來，根據上述特定灰階，進而調整 ，照本發_較佳實施例職之方法，上述之 另一 計每一灰階的像素個數。在本發明的 中!、: 特定比例約90%。在本發明的再一 ^ 上述之5周整影像步驟包括調整影像之韋7#掸2 以及根據蚊灰階影像之對比。〜像之儿紅盈 本發明的祕實_所述之枝，上述之影像顯 ^ 一$光源之—螢幕，調整影像步驟包括;If據彳±二 ==源的亮度以及調整影像之對=== 一索=、2述之§周整源亮度步驟以特定灰階為 中:上述之調度。在本發明的再-實施例 查表決妓像师__—索引值， 計裝種影像處理裝置’此裝置包括：一統 個像素，並玉裝置。統計裝置用於接收—影像的多 布L出一像素的-灰階分布，再根據灰階分 灰階，谁:疋ΛΡ&。影像調整裝置用以根據上述特定 小於此特定^影像’其中有一特定比例的像素的灰階是 整iC，較佳實施例所述之裝置’上述之影像調 衣置包括—免度調整心以及―對比度調 度裝置以及對比度調整裝置是 歧$ 200845729 HM-2006-0114-TW 22503twf.doc/n 別給予影像一亮度增益以及一對比調整參數。在本發明的 另一實施例中，上述之影像顯示於具有一背光源之一螢 幕，且影像調整裝置包括一亮度調整裝置。此亮度調整裝 置疋根據特疋灰階調整背光源的亮度。在本發明的再一， 施例中，上述之亮度調整裝置包括一灰階/亮度對照表。^匕 灰階/亮度對照表以特定灰階為一索引值，查表決定背光源 亮度。 /7' 依照本發明的較佳實施例所述之裝置，上述之對比产 調整裳置包括-_鱗比度對照表。此灰階/對比度對ς 表以特定灰階為一索引值，查表決定影像之對比。^本發 明的再-實施例中，上述之統計裝置更肋統計每一灰^ 的像素個數。在本發明的又—實施例中，上述 實質上約90%。 l 、，本發明藉由統計裝置進行統計影像像素之灰階分布， ==象素之灰階分布’找出一特定灰階，再根據得 影整影像之至少亮度與對比參數，使 為，本2之上述和其他目的、特徵和優點能更明顯 =下 較佳實關，並配合所_式，作詳細說 【實施方式】 程Η圖本發明實闕之適紐影像娜方法之流 圖二本發明實施例之影像處理裝置之方塊 4终考圖3及圖4 ’此影像處理裝置400包括統 8 200845729 HM-2006-0114-TW 22503twf.doc/n 計裝置及影像調整裝置術，其中影像調整裝置搬 尚包括免度調整裝置403及對比度調整裝置4()4。此 例的電路運作簡單敘述如下：首先，提供—影像，此^像 具有多個像素(步驟S3〇l)。此影像例如為數位相機、數位 攝影機所輸A的触影像、電騎輸&的倾影像 訊(video)等。 接著，將上述影像傳送至一統計裝置401中，並進行 統計此影像像素的灰階分布(步驟S3G2)。於此步驟遺 中’統計裝置401進行整個影像之像素_灰階分析，以— 灰階為例，也就是找出各個灰階，分财多少個像素。例 灰階值為0時之個數有100個；影像像素於 XP白值為1 %之個數有2G個；影像像素於灰階值為2時之 個數為10個；影像像素於灰階值3、4、5.....直到八析 像像素於灰階值為255時，即完成此影像像素健之 刀析。此統計過程巾記錄影像在每―灰階所佔有的像素個 數’緣示為—分布崎H1，稱為灰階分^®(hiStGgram)， ，圖认所示。歸’依齡布輯HI計算像素個數之累 加’繪示一累加曲線S 1。 士—接下來，根據上述之灰階分布的累加曲線si ,找出一 t灰p& ’其中上34像素中，有—特定比例之像素的灰階 述特定灰階(步驟S3〇3)。為了讓此實施例更加清 ^在此假設此特定_為90%。因此，上述的特定灰階 j就是代表了整個影像中的像素，有鄕的像素的灰階 b Μ寸疋灰階小。若以圖2A來說，由圖2A所統計出來 200845729 HM-2006-0114-TW 225〇3twf.doc/n 的特定灰階將會較小，若以m 办^山回〇 來的特定灰階將會比圖2A ^ 二θ B所統計出 原因在於圖2B雖4 一丰Π:階來的大。 較焭。也就是灰階分布較為極 ^ ^ ί' 素都Ϊ在平均職_，故像素分布錢中P刀的像 最後，根據上述之特定灰階，進而調整 S3 04)。統計^置4 01將此特定灰階分別傳送至影像調^壯 置402中的免度調整裝置4〇3及對比度調整裝置‘二 ，行影像更細部之調^此調整影像又包括：i.於二 =置彻中、，根據上述之特定灰階，給予影像 風，另外也可以據以調整背光源的亮度(步驟幻]二 對比度調整裝置404中，根據上述之特定灰階，給予旦复 -對比調整參數’進行調整影像之職(步驟S3Q6)。二 對比與亮度’影像調整|置4〇2尚可調整其他影像表= 於此不——贅述。 > 双， 上述之壳度增益可根據一灰階/亮度對照表決定其大 小，並給予影像一合適的亮度增益值，進而調整顯示^螢 幕上之影像背光源亮度，使影像不會調整至過亮或過暗。 此灰階/亮度對照表使用特定灰階為索引值，例如為圖 6Α，當判斷索引之值較大，也就是影像亮度較亮時，所需 之梵度增益較大；當判斷索引之值較小，也就是影像亮度 較暗時，所需之亮度增益就需要較小。 上述影像之對比亦可根據一灰階/對比度對照表決定 其調整參數，並給予影像一適合的對比調整參數，進而調 200845729 HM-2006-0114-TW 22503twf.doc/n 整衫像之對比，使影像能顯示出最佳的品質。此灰階/對比 2對照表亦使用特定灰階為索引值，例如為圖6B所示， 田岁索引之值較小，也就是影像亮度較暗時，可將影像 比值調高；當判斷索引之值較大，也就是影像亮度較 亮時’可將影像之對比值調低。Image processing is the function provided by the acquired digital image processing software to make color, brightness, and distance, various image changes, and even to combine two photos through a comparison operation program. For example, some of the work that can be done with images: such as changes in brightness and contrast, can quickly be taken - a sunny day = slice = _ rainy day #. You can even use the image processing process to change the original appearance of the image. Therefore, image processing is simply a matter of changing the image of the image. In order to improve the quality of the surface of the flat-panel display, it is necessary to dynamically adjust the image, for example, using the party degree of the image as a criterion: for darker images, the contrast can be improved, the brightness can be lowered, and the backlight can be lowered; for the brighter image, Lower the g than the 'S week party' and adjust the backlight. For some image processing that needs to determine the brightness of the image, the average brightness of the image is a judgment index that is often used. Figure 1 is a block diagram of a conventional image processing apparatus. Referring to FIG. 1, the image processing apparatus 100 includes a brightness average detection 101, a contrast control unit § (contrast controller) 102, and a brightness controller 103. First, the image is transmitted to the luminance detector 5 200845729 HM-2006-0114-TW 22503twf.doc/n Mean Detector 101 and the average value of the luminance of the image is obtained by the luminance average detector 1〇1. Then, according to the obtained average brightness value as a judgment index, the contrast control controller 102 and the brightness controller 1〇3 are used to adjust the image contrast and brightness of the image, and the backlight can be adjusted accordingly to increase the image display. quality. -^ In many cases, the average brightness is not sufficient to distinguish the brightness of the different images. For example, if there are two images as shown in Figure 2A (image (less dark difference) and ®2B (image difference between light and dark), and the average brightness of the two images is 55, but the image The image of 2B is more effective in the image of Figure 2A. It is assumed that the average brightness is used as the image. When the whole reference is used, it will be mistaken for the brightness component of the image of Figure 2 and Figure 2β. However, if the adjustment of the butterfly adjustment is performed, the effect of the image will be poor, and the image will not be too bright or too dark. Therefore, the calculation of the average brightness of the image alone is not only beneficial. Distinguish the difference between the images in Figure 2A and Figure 2B above, and also cause the image adjustment to have the opposite effect. ^ [Summary] The purpose of this X-month is to provide an adaptive image adjustment method and image processing device. The gray scale distribution of the pixels of the scene can be statistically calculated and analyzed according to the results of statistics and analysis, thereby adjusting the image to the best quality. The present invention proposes an adaptive image adjustment method, which includes at least the following step : provide - image, this image has multiple pixels. Statistically, the gray scale distribution of the pixel. And according to the above gray scale distribution, find a special 200845729 HM-2006-0114-TW 22503twf.doc/n in the above pixels' The gray scale of the pixel having a certain ratio is next, according to the specific gray scale described above, and further adjusted, according to the method of the preferred embodiment, the number of pixels of each gray scale is calculated. In the invention, the specific ratio is about 90%. In the further five weeks of the present invention, the image forming step includes adjusting the image of the image 7#掸2 and the contrast according to the mosquito ash image. The secret of the present invention, the above-mentioned image display, the light source-screen, the image-adjusting step includes: If the data is 彳±2== source brightness and the adjusted image pair === one cable =, 2 § Weekly source brightness step with a specific gray level as the middle: the above-mentioned scheduling. In the re-implementation of the present invention, the voting imager __-index value, the device type image processing device 'this device includes: One pixel and jade device. The statistical device is used to receive - multiple images of the image a pixel-gray scale distribution, and then according to the gray level grayscale, who: 疋ΛΡ & image adjustment device is used according to the above specific smaller than the specific ^ image 'the gray scale of a specific proportion of pixels is the whole iC, The device described in the preferred embodiment is characterized in that the image-adjusting device includes a-free adjustment core and a contrast scheduling device and a contrast adjustment device. $200845729 HM-2006-0114-TW 22503twf.doc/n Gain and a contrast adjustment parameter. In another embodiment of the invention, the image is displayed on a screen having a backlight, and the image adjustment device includes a brightness adjustment device. This brightness adjustment device adjusts the brightness of the backlight according to the special gray scale. In still another embodiment of the present invention, the brightness adjusting device described above includes a gray scale/brightness comparison table. ^匕 The grayscale/brightness comparison table takes a specific grayscale as an index value, and the lookup table determines the brightness of the backlight. /7' In accordance with the apparatus of the preferred embodiment of the present invention, the above-described contrast-producing skirt includes a -_ scale ratio table. This grayscale/contrast pair ς table has a specific grayscale as an index value, and the lookup table determines the contrast of the image. In a further embodiment of the invention, the statistical device described above counts the number of pixels per ray. In still other embodiments of the invention, the above is substantially about 90%. l, the present invention uses a statistical device to perform gray scale distribution of statistical image pixels, == gray scale distribution of pixels to find a specific gray scale, and then according to at least the brightness and contrast parameters of the image to be imaged, The above and other objects, features and advantages of the present invention can be more obvious = the next is better, and in conjunction with the formula, the detailed description of the method of the present invention is the flow chart of the method of the present invention. Block 4 of the image processing apparatus of the embodiment of the invention, FIG. 3 and FIG. 4 'This image processing apparatus 400 includes a system 8 200845729 HM-2006-0114-TW 22503twf.doc/n meter device and image adjustment device, wherein image adjustment The device removal includes a degree adjustment device 403 and a contrast adjustment device 4 () 4. The circuit operation of this example is briefly described as follows: First, an image is provided, which has a plurality of pixels (step S3〇1). The image is, for example, a digital camera, a touch image transmitted by a digital camera, a video of a ride, and the like. Then, the above image is transmitted to a statistical device 401, and the gray scale distribution of the image pixel is counted (step S3G2). In this step, the statistical device 401 performs the pixel_grayscale analysis of the entire image, taking the grayscale as an example, that is, finding each grayscale and dividing the number of pixels. When the grayscale value is 0, there are 100; the image pixel has 2G in the XP white value of 1%; the image pixel has 10 in the grayscale value of 2; the image pixel is gray. The order value of 3, 4, 5..... until the eight-resolution pixel has a gray-scale value of 255, that is, the image pixel is analyzed. The statistical process paper records the number of pixels occupied by each gray scale as the distribution of the texture H1, called the gray level division ^® (hiStGgram), as shown in the figure. The accumulation of the number of pixels calculated by HI is shown as an accumulation curve S1. Next, based on the cumulative curve si of the gray scale distribution described above, it is found that a t gray p&' of the upper 34 pixels has a specific gray scale of the pixel of a certain ratio (step S3〇3). In order to make this embodiment clearer, it is assumed here that this specific _ is 90%. Therefore, the above-mentioned specific gray level j represents a pixel in the entire image, and the gray level of the defective pixel is smaller than the gray level. As shown in Fig. 2A, the specific gray level of 200845729 HM-2006-0114-TW 225〇3twf.doc/n, which is calculated by Fig. 2A, will be smaller, if the specific gray level is returned by m The reason will be compared with Fig. 2A ^ 2θ B is that Fig. 2B is a large one. More ambiguous. That is to say, the gray scale distribution is extremely ^ ^ ί' The prime is in the average job _, so the image of the P knife in the pixel distribution money Finally, according to the specific gray scale mentioned above, and then adjust S3 04). The statistics set 4 01 respectively transmits the specific gray scale to the degree adjustment device 4〇3 and the contrast adjustment device '2 in the image adjustment and expansion 402, and the adjustment image of the line image further includes: i. In the second = setting, according to the specific gray level described above, the image wind is given, and the brightness of the backlight may be adjusted accordingly (step phantom). The contrast adjustment device 404 is given according to the specific gray level described above. -Compare adjustment parameter 'to adjust the image position (step S3Q6). Second contrast and brightness 'image adjustment|set 4〇2 can still adjust other image table = here is not - repeat. > double, the above shell gain The size can be determined according to a gray scale/brightness comparison table, and an appropriate brightness gain value is given to the image, thereby adjusting the brightness of the image backlight on the display screen so that the image is not adjusted to be too bright or too dark. The brightness/brightness comparison table uses a specific gray scale as an index value, for example, as shown in FIG. 6Α, when the value of the index is judged to be large, that is, when the brightness of the image is bright, the required vantage gain is large; when the value of the index is small, Image brightness In the darker, the required brightness gain needs to be smaller. The comparison of the above images can also be based on a grayscale/contrast comparison table to determine the adjustment parameters, and give the image a suitable contrast adjustment parameter, and then adjust 200845729 HM-2006- 0114-TW 22503twf.doc/n The contrast of the whole shirt image makes the image show the best quality. This grayscale/contrast 2 comparison table also uses the specific gray scale as the index value, for example, as shown in Figure 6B. The value of the index is small, that is, when the brightness of the image is dark, the image ratio can be increased; when the value of the index is judged to be large, that is, when the brightness of the image is brighter, the contrast value of the image can be lowered.
、，a如先前技術中所指出，由於習知技術中以平均值做為 判斷索引的作法並無法準確判斷影像的亮暗程度，容易造 $恰當的影像處理結果。如本發明之實施例巾依據灰階 ^布圖求得判斷索⑽做法可以更精確地掌握影像之間的 冗暗程度，以對應出適當的影像處理參數。 2以先前技術中所提及之平均值一樣的影像為例（如g 及圖2B)，經過統計裝置4〇1分析及統計之灰階分^ 可以得出如圖5A及圖5B的結果。圖5A及圖5B < 彡做階帅〜扮），左叙縱㈣影像像素個數 圖^右邊之縱轴為影像像素個數累加百分比。於圖5A石 例(者^_’以轉影像像素個㈣加百分比9G%的方式^ 據、9G%的成分做為後續影像處理的々 2豕’所對應出的影像灰階值分別是121及225，此ΐ2ι ^ 別表不圖2八及圖沈的判斷索引值㈣挪⑽inde 夺俊ί—步來看’判斷索引值是用來決定圖Μ和圖 二確絲像品質在所制吳 是利用習知裝置所獲得之景;:::值來 11 200845729 HM-2006-0114-TW 22503twf.doc/n 圖2B之衫像有不當的調整；反觀若是使用本發明所描述 之方法及裝置，藉由判斷索引值121及奶的顯著差異， 便可刀別為衫像圖2A與圖2B對應出適當的增益值。明顯 地’以本發明的精㈣實施出來的實關可㈣原本平均 值樣的兩張影像做很好的區別，並且可對影像做出 當的調整。 值付-提的是’軸上述實施例巾已經對影像處理裝 置減出了-個可能的型態，但所屬技術領域中具有通常 知識者應當知逞，各廠朗於統計裝置4()1以及影像調整 裝置402的設計方式都不一#，因此本發明之應用當不限 制於此種可能的型態。換言之，只要是統計裝置4〇1能分 ^並統計出影像之灰階分布，並根據此灰階分布找出一特 定灰階，進_整上述之影像，使影像品質得以提升，就 已經疋付合了本發明的精神所在。 綜上所述，本發明因採用統計裝置，並藉由此統計裝 置統計並分析影絲叙灰階分布，再_像素之灰階分 布"周正衫像之焭度與對比，使影像能呈現最佳的品質。 然而，不會再因為不同的影像具有相同的亮度平均值時， 造成不恰當的影·理結果。目此，本發霞有效地分析 出各種影像的亮暗成分，絲據各個影像的灰階分布，進 而將這些影像調整至最佳的品質。 雖然本發明已經以較佳實施例揭露如上，然其並非用 以限疋本發明，任何所屬技術領域具有通常知識者，在不 脫離本發明之精神和範圍内，當可作些許之更動與潤飾， 12 200845729 HM-2006-0114-TW 22503twf.doc/n 因此本發明之保護範圍當視後附之申請專利範園戶 為準。 所界定者 【圖式簡單說明】 圖1繪示為習知影像處理裝置之方塊圖。 圖2A繪示為影像之示意圖（亮暗差異較小）。 圖3 圖2B繪示為另一影像之示意圖（亮暗差異_ 程圖 繪示為本發明實施例之適應性影像=)。 疋方法之流 圖4繪示為本發明實施例之影像處理裝置 圖5A繪示為圖2八影像像素之灰階分布圖<方塊圖。 圖5B繪示為圖2B影像像素之灰階分布^。 圖6A繪示為影像調整之灰階/亮度對照表。 圖6B繪示為影像調整之灰階/對比度對照表。 【主要元件符號說明】 100、400 :影像處理裝置 1〇1 :亮度平均值檢測器 102 :對比控制器 103 :亮度控制器 S301〜S306:本發明實施例之步驟 401 :統計裝置 402 :影像調整裝置 403 ··亮度調整裝置 404 :對比度調整裝置 HI、H2 :分布曲線 SI、S2 :累加曲線 13a, as pointed out in the prior art, because the average value of the index in the prior art is not able to accurately determine the brightness of the image, it is easy to make an appropriate image processing result. According to the embodiment of the present invention, the determination of the judgment line (10) according to the gray scale layout can more accurately grasp the degree of redundancy between the images to correspond to appropriate image processing parameters. 2 Taking the image with the same average value mentioned in the prior art as an example (such as g and FIG. 2B), the results of the statistical apparatus 4〇1 analysis and statistical gray scales can be obtained as shown in FIGS. 5A and 5B. Figure 5A and Figure 5B < 彡 阶 阶 〜 扮 扮 扮 , , , , , , , 四 四 四 四 四 四 四 四 四 四 四 四 四 四 四 四 四 四 四 四 四 四 四 四 四In Fig. 5A, the stone image values corresponding to the stone image (the ^_' are rotated by the image pixel (4) plus the percentage of 9G%), and the 9G% component is used as the subsequent image processing. And 225, this ΐ 2 ι ^ Do not show Figure 2 VIII and Figure Shen judgment index value (four) move (10) inde 夺俊 ί - step to see 'judge index value is used to determine the map and Figure 2 is the quality of the silk in the system is The view obtained by the conventional device;::: value is 11 200845729 HM-2006-0114-TW 22503twf.doc/n Figure 2B has a improper adjustment of the shirt image; in contrast, if the method and device described in the present invention are used, By judging the significant difference between the index value 121 and the milk, the appropriate gain value can be obtained for the shirt as shown in Fig. 2A and Fig. 2B. Obviously, the actual value can be implemented by the fine (4) of the present invention. The two images are very well distinguished, and the image can be adjusted as it is. The value is - the 'axis of the above embodiment has been reduced to the image processing device - a possible type, but belongs to Those with ordinary knowledge in the technical field should know that each factory is in the statistical device 4 () 1 and image The design of the whole device 402 is different, so the application of the present invention is not limited to such a possible type. In other words, as long as the statistical device 4〇1 can divide and count the gray scale distribution of the image, and according to The grayscale distribution finds a specific grayscale, and the image is improved to improve the image quality, which has already paid the spirit of the present invention. In summary, the present invention uses statistical devices and borrows The statistical device statistically analyzes and analyzes the grayscale distribution of the shadows, and then the gradation and contrast of the grayscale distribution of the pixel, which makes the image show the best quality. However, it will not be because of different images. When the same brightness average value is used, it causes inappropriate image and effect results. Therefore, this hair is effective to analyze the light and dark components of various images, and according to the gray scale distribution of each image, the images are adjusted to the most. The present invention has been disclosed in the above preferred embodiments, but it is not intended to limit the invention, and any one of ordinary skill in the art without departing from the spirit and scope of the invention In the meantime, when some changes and refinements can be made, 12 200845729 HM-2006-0114-TW 22503twf.doc/n Therefore, the scope of protection of the present invention is subject to the patent application of the attached patent. BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 is a block diagram of a conventional image processing apparatus. Figure 2A is a schematic diagram of an image (the difference between light and dark is small). Figure 3 Figure 2B is a schematic diagram of another image (light and dark difference _ FIG. 4 is a diagram showing an image processing apparatus according to an embodiment of the present invention. FIG. 5A is a grayscale distribution diagram of the image pixels of FIG. Figure 5B is a gray scale distribution of the image pixels of Figure 2B. FIG. 6A is a grayscale/brightness comparison table for image adjustment. FIG. 6B is a gray scale/contrast comparison table for image adjustment. [Main component symbol description] 100, 400: image processing device 1〇1: brightness average detector 102: contrast controller 103: brightness controller S301~S306: step 401 of the embodiment of the invention: statistical device 402: image adjustment Device 403 · Brightness adjusting device 404: Contrast adjusting device HI, H2: Distribution curve SI, S2: Accumulation curve 13