CN1464744A - Method for automatic discriminating scanning compression ratio of scanner - Google Patents

Abstract

The present invention relates to a method for judging the scanning compression ratio, in particular to a method for automatically judging the scanning compression ratio of a scanner. The present invention firstly analyzes the image data obtained after pre-scanning, and divides the image data into several regions, each The pixel values of adjacent pixels in the area are relatively close. Next, the scan compression ratio of each area is determined by the difference between the pixel values of adjacent pixels in each area, and a standard value for each area is determined. Finally, the The standard value of each area is completely stored in the buffer memory (buffer), and the difference between the standard value of each area and each pixel in this area is stored in the buffer memory, and an area is designated to store each phase Information about whether the corresponding block has compression is used to determine whether the data in the block is compressed.

Description

Automatic Discrimination Method of Scanning Compression Ratio of Scanner

technical field

The invention relates to a method for judging the scanning compression ratio, in particular to a method for automatically judging the scanning compression ratio of a scanner, so as to reduce the amount of data and the times of data transmission, and improve the scanning speed.

Background technique

For today's information users, especially personal computer users, the mode of contacting computer information has entered the era of so-called multimedia (Multi-Media) from the relatively monotonous text mode, and multimedia means that the information includes text , video, audio and other content, and in order to present the data in front of the audience in the form of multimedia, a variety of multimedia devices that can retrieve video or audio have been developed. Because the multimedia data contains more content, the capacity of the memory required to process the multimedia data needs to be higher than the monotonous text mode, so that the multimedia data can be presented in a smoother mode.

For image input devices, scanners and digital cameras are relatively common devices at present. A digital camera uses digital information to store captured images. It uses a disk that can record images or a memory card from the Personal Computer Memory Card International Association (PCMCIA) to store still images. . In order to save the memory space used by the storage media, the images captured by digital cameras are usually stored in compressed files, and the common one is the still image compression standard (Joint Photographic Experts Group; JPEG) file format.

As far as the types of scanners are used, scanners can usually be divided into handy scanners, desktop scanners or flat bed scanners, and sheet-feed scanners. three kinds. The resolution of scanning is in dots per inch (dpi). The higher the dpi, the higher the quality of the machine, but the scanning time is also longer. When scanning color images, many scanners must scan the RGB three primary colors separately, so the scanning action has to be repeated three times, which also makes the scanning time longer.

A desktop scanner is a more commonly used scanner, which is used to convert some documents to be scanned, such as transmissive documents (such as transparencies) or reflective documents (such as photos or paper) into digital data. Generally speaking, the photoelectric sensor module used in desktop scanners mainly includes a photoelectric sensor component, which can be: a charge coupled device (CCD) or a contact image sensor (CIS). . The desktop scanner is used to convert the documents placed on the glass platform into digital data through the scanning process and input them into the personal computer for further use.

During the scanning process, the image to be scanned reflects or transmits the light emitted by the light source, and the reflected light or transmitted light is received by the photoelectric sensor module. After that, it is connected to a host, such as a personal computer, through a control circuit, and the image processing is performed through the personal computer.

As is generally known, various colored lights can be obtained by combining the three primary colors of light—red (R), blue (B) and green (G)—in different ratios. Conversely, various colored light can be regarded as a combination of R, G and B. Hereinafter, the components of R, G, and B included in various colored lights are simply referred to as red (R) materials, green (G) materials, and blue (B) materials.

During the scanning process, the photoelectric sensing module first retrieves the R data, G data and B data of each pixel in a row of the image data to be scanned, and generates corresponding analog signals. These analog signals are then sent to an analog-digital converter to generate digital data for processing by the next unit. Then the photoelectric sensing module retrieves the R data, G data and B data in the next column of the image to be scanned, and performs similar actions. In this process, according to the different ways of scanning and processing data, it can be roughly divided into two types: one-channel scanning and three-channel scanning.

Referring to FIG. 1A and FIG. 1B , these two figures are schematic diagrams of sending image data in conventional technology. FIG. 1A shows how to select the scanning starting positions and scanning areas of R, G and B in the conventional technology. In FIG. 1A , each grid represents a color data of a pixel on the area to be scanned, and the number in the pixel represents the position of the pixel on the area to be scanned. In the description of the present invention, the image data of a pixel-the pixel value is represented by the symbol P(x, y), wherein x represents a column coordinate, and y represents a row coordinate. For example: P(2n-1, 1) represents the pixel value of the first pixel in the 2n-1 (n is a natural number) column.

In the conventional technology, when scanning the 2n-1th column, the scanning start positions of R, G, and B are all located at the first pixel of the area to be scanned, and the scanning area is a complete column. That is, its resolution is full.

And FIG. 1B shows the corresponding R, G and B data generated corresponding to each pixel. In FIG. 1B , R(x, y), G(x, y) and B(x, y) respectively represent the color data included in the pixel value P(x, y). If the R, G, and B data of each pixel are represented by 8 bits, the amount of data generated by each pixel is 3*8=24 bits.

It can be seen from FIG. 1A and FIG. 1B that when a conventional scanner transmits image data to a personal computer, all R, G and B data of each pixel are sent out. The data to be transmitted will first be stored in the buffer memory (buffer) on the scanner. When the buffer memory reaches the upper limit of its storage or the buffer memory receives a scan termination signal, the buffer memory will Send the data stored in it to the host for processing. Generally speaking, the memory space occupied by pixels is quite large, so if the R, G, and B data of each pixel are all stored in the buffer memory without processing, the buffer memory will often reach its limit. The upper limit of data storage and the data stored in it must be transmitted out. When the amount of data is large, the buffer memory will be full, and the number of data transmissions will also increase accordingly, so the scanning speed will slow down and the life of the buffer memory will be shortened.

The bottleneck of the speed of the traditional scanning device often occurs when the scanning device transmits data to the host. Due to the large amount of data, the data must be transmitted to the host in batches and the scanning speed is reduced. Therefore, in order to speed up the scanning speed, reducing the amount of data transmitted to the host will be the most effective way.

Contents of the invention

The main purpose of the present invention is to overcome the deficiencies and defects of the prior art, and provide a method to compress the image data in advance by using the scanning compression ratio automatic judgment method of the scanner to reduce the amount of data to be transmitted.

The second object of the present invention is to compress the image data in advance by using the automatic determination method of the scanning compression ratio of the scanner, so as to reduce the number of data transmission from the buffer memory to the host computer.

The third object of the present invention is to compress the image data in advance by using the automatic determination method of the scanning compression ratio of the scanner to speed up the scanning speed.

The fourth object of the present invention is to compress the image data in advance by using the automatic determination method of the scanning compression ratio of the scanner, so as to reduce the number of times when the buffer memory is full.

Another object of the present invention is to compress the image data in advance by using the automatic determination method of the scanning compression ratio of the scanner, so as to prolong the service life of the buffer memory.

According to the above-mentioned purpose, the present invention provides a method for compressing the image data in advance by using the automatic identification method of the scanning compression ratio of the scanner to reduce the amount of data. The present invention firstly analyzes the image data obtained after pre-scanning, and divides the image data into several areas, and the pixel values of adjacent pixels in each area are relatively close. Next, the scan compression ratio of each area is determined according to the pixel value difference of adjacent pixels in each area, and a standard value for each area is determined. The standard value can be the average pixel value of all pixels in the area, or the minimum pixel value of all pixels in the area. Finally, the standard value of each area is completely stored in the buffer memory (buffer), and the difference between the standard value of each area and each pixel in the area is stored in the buffer memory, and an area is designated for storage Whether each corresponding block has compressed information is used to determine whether the data in the block is compressed.

In order to achieve the above object, the present invention provides a method for automatically judging the scanning compression ratio, comprising: pre-scanning a document or a pattern to obtain an image data, the image data includes a first pixel, a second pixel and a third pixel pixel, the second pixel is adjacent to the first pixel and the third pixel; analyzing a first difference between the first pixel and the second pixel and a first difference between the second pixel and the third pixel Two difference values and obtain a standard value; completely store the standard value in a memory; store a third difference value of the first pixel relative to the standard value, a fourth difference of the second pixel relative to the standard value value and a fifth difference between the third pixel and the standard value in the memory; transmit a data in the memory to a host; and combine the data into the image data.

The standard value may be an average value of the first pixel, the second pixel and the third pixel.

The standard value may also be the minimum value of the first pixel, the second pixel and the third pixel.

The present invention also provides a method for automatically judging the scanning compression ratio, which includes: pre-scanning a file or a pattern to obtain an image data, the image data includes a plurality of first pixels, a plurality of second pixels, a plurality of second pixels Three pixels, a plurality of fourth pixels, a plurality of fifth pixels and a plurality of sixth pixels, the plurality of first pixels are adjacent to the plurality of second pixels, the plurality of second pixels adjacent to the plurality of third pixels, the plurality of third pixels adjacent to the plurality of fourth pixels, the plurality of fourth pixels adjacent to the plurality of fifth pixels, the plurality of The fifth pixel is adjacent to the plurality of sixth pixels; analyzing the plurality of first difference values of the plurality of first pixels relative to the plurality of second pixels, the plurality of second pixels relative to the plurality of A plurality of second difference values of the plurality of third pixels, a plurality of third difference values of the plurality of third pixels relative to the plurality of fourth pixels, and a plurality of third difference values of the plurality of fourth pixels relative to the plurality of A plurality of fourth difference values of the fifth pixel and a plurality of fifth difference values of the plurality of fifth pixels relative to the plurality of sixth pixels, if the first difference is relative to the second difference value The difference between the first difference and the fifth difference is small, the difference between the fourth difference and the fifth difference is small, and the difference between the third difference and the second difference is relatively large, then the image data is divided into a first block and a second block and take a first standard value and a second standard value in the first block and the second block, the first block includes the plurality of first pixels , the plurality of second pixels and the plurality of third pixels, the second block includes the plurality of fourth pixels, the plurality of fifth pixels and the plurality of sixth pixels; completely store the The first standard value and the second standard value are stored in a memory; storing a sixth difference value of the plurality of first pixels relative to the first standard value, and storing the plurality of second pixels relative to the first standard A seventh difference value of the value and an eighth difference value of the plurality of third pixels relative to the first standard value are stored in the memory, and the values of the plurality of fourth pixels relative to the second standard value are stored A ninth difference value, a tenth difference value of the plurality of fifth pixels relative to the second standard value, and an eleventh difference value of the plurality of sixth pixels relative to the second standard value are in the in memory; transmitting a data in the memory to a host; and combining the data into the image data.

The first standard value may be an average value of the plurality of first pixels, the plurality of second pixels, and the plurality of third pixels.

The first standard value may also be the minimum value of the plurality of first pixels, the plurality of second pixels and the plurality of third pixels.

The second standard value may be an average value of the plurality of fourth pixels, the plurality of fifth pixels, and the plurality of sixth pixels.

The second standard value may also be a minimum value of the plurality of fourth pixels, the plurality of fifth pixels, and the plurality of sixth pixels.

The present invention further provides a method for automatically judging the scanning compression ratio, which includes: pre-scanning a document or a pattern to obtain an image data, the image data includes a plurality of first pixels, a plurality of second pixels, a plurality of second pixels Three pixels, a plurality of fourth pixels, a plurality of fifth pixels and a plurality of sixth pixels, the plurality of first pixels are adjacent to the plurality of second pixels and the plurality of fourth pixels , the second pixel is adjacent to the plurality of third pixels and the plurality of fifth pixels, the plurality of third pixels is adjacent to the plurality of sixth pixels, and the plurality of fourth pixels Adjacent to the plurality of fifth pixels, the plurality of fifth pixels adjacent to the plurality of sixth pixels; analyzing the plurality of first pixels relative to the plurality of second pixels and the plurality of A plurality of first difference values and a plurality of second difference values of the fourth pixel, a plurality of third difference values of the plurality of second pixels relative to the plurality of third pixels and the plurality of fifth pixels and the plurality of fourth difference values, the plurality of fifth difference values of the plurality of third pixels relative to the plurality of sixth pixels, the multiplicity of the plurality of fourth pixels relative to the plurality of fifth pixels The size of the sixth difference value and the plurality of seventh difference values of the plurality of fifth pixels relative to the plurality of sixth pixels, if the difference between the first difference value and the third difference value is small, If the difference between the sixth difference and the seventh difference is small, and the second difference, the fourth difference and the fifth difference are all greater than a first standard value, then the image data is divided into a first block and a second block and take a second standard value and a third standard value in the first block and the second block, the first block includes the plurality of first pixels, the plurality of first pixels Two pixels and the plurality of third pixels, the second block includes the plurality of fourth pixels, the plurality of fifth pixels and the plurality of sixth pixels; completely store the second standard value and the plurality of sixth pixels; The third standard value is stored in a memory; an eighth difference value of the plurality of first pixels relative to the second standard value, a ninth difference value of the plurality of second pixels relative to the second standard value are stored The difference and a tenth difference of the plurality of third pixels relative to the second standard value are stored in the memory, and an eleventh difference of the plurality of fourth pixels relative to the third standard value is stored value, a twelfth difference value of the plurality of fifth pixels relative to the third standard value and a thirteenth difference value of the plurality of sixth pixels relative to the third standard value in the memory; Transmitting a data in the memory to a host; and combining the data into the image data.

The second standard value is an average value of the plurality of first pixels, the plurality of second pixels and the plurality of third pixels.

Description of drawings

FIG. 1A shows how the traditional technology selects the scanning starting positions and scanning areas of R, G and B;

FIG. 1B is a situation of corresponding R, G and B data generated corresponding to each pixel;

2A is a schematic diagram of dividing the image data obtained by pre-scanning into multiple blocks;

FIG. 2B is an arrangement of pixel data in one of the blocks;

FIG. 3 is a schematic diagram of storing one of the blocks on the buffer memory using the method of the present invention; and

FIG. 4 is a flow chart of the scanner scanning compression ratio automatic discrimination method of the present invention.

Explanation of main symbols in the figure:

R(x, y) Image data of red pixel - pixel value

G(x, y) Image data of green pixel - pixel value

B(x, y) Image data of blue pixel - pixel value

x column coordinates

y row coordinate

k The number of pixels that can be accommodated in the block

q standard value

The standard value of q ₁ red pixel

The standard value of q ₂ green pixels

The standard value of q ₃ blue pixels

Detailed ways

The specific implementation manner of the present invention will be described in detail below in conjunction with the accompanying drawings and examples.

Generally, the methods for compressing image data during scanning currently adopt a fixed compression ratio to compress image data, so as to reduce the amount of data to be transmitted. However, when the compression ratio is fixed, it is difficult to achieve an optimal balance between each part of the image and the compression ratio. When the compression ratio is high, the part of the image will be easily distorted. When it is necessary to maintain the authenticity of the image and not obtain a distorted image, the compression used is relatively low, but the amount of stored data will become relatively large, thus losing the purpose of compressing the data. Therefore, it is necessary to use different compression ratios for scanning according to the different pixels of each part of the image, so that the image data can maintain its original authenticity after the efficient compression process.

The invention provides a method for automatically judging the scanning compression ratio of a scanner to compress the image data in advance to reduce the amount of data. The present invention firstly analyzes the image data obtained after pre-scanning, and divides the image data into several areas, and the pixel values of adjacent pixels in each area are relatively close. In order to make the pixel values of adjacent pixels in each region closer, a standard value can be preset in the present invention. When the difference between two adjacent pixels is greater than the standard value, the two adjacent pixels must be divided into two regions. Next, the scan compression ratio of each area is determined according to the pixel value difference of adjacent pixels in each area, and a standard value for each area is determined. The standard value can be the average pixel value of all pixels in the area, or the minimum pixel value of all pixels in the area. Finally, the standard value of each area is completely stored in the buffer memory (buffer), and the difference between the standard value of each area and each pixel in the area is stored in the buffer memory, and an area is designated for storage Whether each corresponding block has compressed information to determine whether the data in the block is compressed.

The present invention firstly analyzes the image data obtained by the scanner after pre-scanning, and divides the image data into multiple blocks (refer to FIG. 2A). In order to ensure that the pixel values of two adjacent pixels in each block are relatively close, a standard value can be preset in the present invention. When the difference between two adjacent pixels is larger than the standard value, the two adjacent pixels must be divided into two different blocks. When the difference between two adjacent pixels is smaller than the standard value, the two adjacent pixels must be divided into the same block. The sizes of the multiple blocks are not the same, and are determined according to the difference between the pixel values of adjacent pixels in the block. If the difference between the pixel values of adjacent pixels of the image data is small, that is, the step of not dividing the image data is performed, and the image data is regarded as a block. The method introduced in this embodiment is to divide the image data into several blocks, but it does not limit the protection scope of the present invention. For the divided blocks, the difference between the pixel values of the pixels in the block is quite small. The divided block may exist in the form of one line, or be divided into multiple areas within one line, or contain multiple lines within the block. The so-called definition of a line refers to the range of a line that can be scanned by a computer-controlled display. Because a plane is usually composed of many lines, during the scanning process, the computer-controlled display of the scanner also divides the document to be scanned into many lines for storage, and finally transmits the data to the host computer and then combines the lines. into this file. The data of this line is usually a column of data.

Referring to FIG. 2B , this is the arrangement of pixel data in one block, but it does not limit the protection scope of the present invention. The pixel image data-pixel value is represented by the symbol P(x, y), and x represents the column coordinate, and y represents the row coordinate. For example: P(2n-1, 1) represents the pixel value of the first pixel in the 2n-1 (n is a natural number) column. R(x, y), G(x, y) and B(x, y) respectively represent the color data contained in the pixel value P(x, y). The pixel value difference of each pixel in the block is small, and the block includes k pixels.

Next, a standard value is taken as the standard value of the pixel value of each pixel in the block, and the standard value is completely stored in the buffer memory. The standard value can be the average value of the pixel values of each pixel, or the minimum value of the pixel values of each pixel. Next, calculate the difference between the pixel value of each pixel and the standard value, and store the difference in the buffer memory.

Referring to FIG. 3 , it is a schematic diagram of storing one of the blocks in the buffer memory by using the method of the present invention. After calculating the standard value q in each block and completely storing the standard value q in the buffer memory, then calculating the difference between the pixel value of each pixel and the standard value q. Among them, q ₁ represents the standard value of red pixel data, q ₂ represents the standard value of green data, and q ₃ represents the standard value of blue data. After the first difference between the pixel value of the first pixel and the standard value q is calculated, the first difference is then stored in the buffer memory. After calculating the second difference between the pixel value of the second pixel and the standard value q, the second difference is then stored in the buffer memory. If the block has k pixels, after calculating the kth difference between the pixel value of the kth pixel and the standard value q, the kth difference is then stored in the buffer memory. When the pixel's texel value is the same as the standard value q, this difference is recorded as zero.

When the standard value in each block is completely stored in the buffer memory, and the difference between the pixel value of each pixel of each block and each standard value is stored in the buffer memory, the data stored in the buffer memory is then transferred to the buffer memory. Host transmission, and the step of combining images in the host, so that the images can be completely restored on the host. The method adopted in the present invention does not limit the range size of each block, so the compression ratio of each block changes with the difference of the pixel values of adjacent pixels in each block, so the ratio of image distortion and compression ratio can be adjusted To achieve an optimal balance, the image data can be appropriately compressed through this appropriate compression method, so as to reduce the time of data transmission and prolong the life of the buffer memory.

FIG. 4 is a flow chart of the scanner scanning compression ratio automatic discrimination method of the present invention. Firstly, the image data obtained after pre-scanning by the scanner is divided into multiple blocks by analyzing the difference between the pixel values of adjacent pixels, and the difference between the pixel values of adjacent pixels in each block is less than A set value of 40. Next, a standard value is obtained in each block, and the standard value is completely stored in the buffer memory 41 . Next, the first difference between the first pixel of each block and the standard value of each block is calculated, and the first difference is stored in the buffer memory 42 . Next, the second difference between the second pixel of each block and the standard value of each block is calculated, and the second difference is stored in the buffer memory 43 . Next, the k-th difference between the nth pixel of each block and the standard value of each block is calculated, and the k-th difference is stored in the buffer memory 44 . Finally, the data in the buffer memory is transmitted to the host computer for image combination step 45 .

Based on the above, the present invention provides a method for compressing the image data in advance by using the automatic identification method of the scanning compression ratio of the scanner to reduce the amount of data. The present invention firstly analyzes the image data obtained after pre-scanning, and divides the image data into several areas, and the pixel values of adjacent pixels in each area are relatively close. Next, the scan compression ratio of each area is determined according to the pixel value difference of adjacent pixels in each area, and a standard value for each area is determined. The standard value can be the average pixel value of all pixels in the area, or the minimum pixel value of all pixels in the area. Finally, the standard value of each area is completely stored in the buffer memory (buffer), and the difference between the standard value of each area and each pixel in the area is stored in the buffer memory, and an area is designated for storage Whether each corresponding block has compressed information is used to determine whether the data in the block is compressed.

The above description is only a preferred embodiment of the present invention, and this embodiment is only used for illustration rather than limiting the protection scope of the present invention. Changes can still be made and implemented within the scope of not departing from the essence of the present invention, and these changes should still belong to the scope of the present invention. Therefore, the scope of the present invention is defined by the scope of the claims.

Claims (10)

1. a scan compression is characterized in that than the method for differentiating automatically, comprises:

Sweep a file or a pattern in advance to obtain an image data, this image data comprises one first pixel, one second pixel and one the 3rd pixel, and this second pixel is adjacent to this first pixel and the 3rd pixel;

Analyze this first pixel with respect to one first difference of this second pixel and this second pixel with respect to one second difference of the 3rd pixel and obtain a standard value;

This standard value of complete storage is in an internal memory;

Store this first pixel with respect to one the 3rd difference of this standard value, this second pixel with respect to one the 4th difference of this standard value and the 3rd pixel with respect to one the 5th difference of this standard value in this internal memory;

Transmit on data to a main frame in this internal memory; And

Make up this data and be this image data.

2. scan compression as claimed in claim 1 is characterized in that than the method for differentiating automatically above-mentioned standard value is a mean value of this first pixel, this second pixel and the 3rd pixel.

3. scan compression as claimed in claim 1 is characterized in that than the method for differentiating automatically above-mentioned standard value is the minimum value of this first pixel, this second pixel and the 3rd pixel.

4. a scan compression is characterized in that than the method for differentiating automatically, comprises:

Sweep a file or a pattern in advance to obtain an image data, this image data comprises a plurality of first pixels, a plurality of second pixel, a plurality of the 3rd pixel, a plurality of the 4th pixel, a plurality of the 5th pixel and a plurality of the 6th pixel, these a plurality of first pixels are adjacent to these a plurality of second pixels, these a plurality of second pixels are adjacent to these a plurality of the 3rd pixels, these a plurality of the 3rd pixels are adjacent to these a plurality of the 4th pixels, these a plurality of the 4th pixels are adjacent to these a plurality of the 5th pixels, and these a plurality of the 5th pixels are adjacent to these a plurality of the 6th pixels;

Analyze a plurality of first differences of these a plurality of first pixels with respect to these a plurality of second pixels, these a plurality of second pixels are with respect to a plurality of second differences of these a plurality of the 3rd pixels, these a plurality of the 3rd pixels are with respect to a plurality of the 3rd differences of these a plurality of the 4th pixels, these a plurality of the 4th pixels are with respect to a plurality of the 4th differences and the size of these a plurality of the 5th pixels with respect to a plurality of the 5th differences of these a plurality of the 6th pixels of these a plurality of the 5th pixels, if first difference is less with respect to a difference of the second difference value, the 4th difference is less with respect to a difference of the 5th difference, the 3rd difference differs greatly with respect to one of second difference and the 4th difference, then this image data is divided into one first block and one second block and in this first block and second block, gets one first standard value and one second standard value, this first block comprises this a plurality of first pixels, these a plurality of second pixels and these a plurality of the 3rd pixels, this second block comprises this a plurality of the 4th pixels, these a plurality of the 5th pixels and these a plurality of the 6th pixels;

This first standard value of complete storage and this second standard value are in an internal memory;

Store these a plurality of first pixels with respect to one the 6th difference of this first standard value, these a plurality of second pixels with respect to one the 7th difference of this first standard value and this a plurality of the 3rd pixels with respect to one the 8th difference of this first standard value in this internal memory, and store these a plurality of the 4th pixels with respect to one the 9th difference of this second standard value, these a plurality of the 5th pixels with respect to ten worst individuals or units's value of this second standard value and these a plurality of the 6th pixels with respect to 1 the 11 difference of this second standard value in this internal memory;

Transmit on data to a main frame in this internal memory; And

Make up this data and be this image data.

5. scan compression as claimed in claim 4 is characterized in that than the method for differentiating automatically the first above-mentioned standard value is a mean value of these a plurality of first pixels, these a plurality of second pixels and these a plurality of the 3rd pixels.

6. scan compression as claimed in claim 4 is characterized in that than the method for differentiating automatically the first above-mentioned standard value is the minimum value of these a plurality of first pixels, these a plurality of second pixels and these a plurality of the 3rd pixels.

7. scan compression as claimed in claim 4 is characterized in that than the method for differentiating automatically the second above-mentioned standard value is a mean value of these a plurality of the 4th pixels, these a plurality of the 5th pixels and these a plurality of the 6th pixels.

8. scan compression as claimed in claim 4 is characterized in that than the method for differentiating automatically the second above-mentioned standard value is the minimum value of these a plurality of the 4th pixels, these a plurality of the 5th pixels and these a plurality of the 6th pixels.

9. a scan compression is characterized in that than the method for differentiating automatically, comprises:

Sweep a file or a pattern in advance to obtain an image data, this image data comprises a plurality of first pixels, a plurality of second pixel, a plurality of the 3rd pixel, a plurality of the 4th pixel, a plurality of the 5th pixel and a plurality of the 6th pixel, these a plurality of first pixels are adjacent to these a plurality of second pixels and these a plurality of the 4th pixels, this second pixel is adjacent to these a plurality of the 3rd pixels and these a plurality of the 5th pixels, these a plurality of the 3rd pixels are adjacent to these a plurality of the 6th pixels, these a plurality of the 4th pixels are adjacent to these a plurality of the 5th pixels, and these a plurality of the 5th pixels are adjacent to these a plurality of the 6th pixels;

Analyze these a plurality of first pixels with respect to a plurality of first differences and a plurality of second difference of these a plurality of second pixels with these a plurality of the 4th pixels, these a plurality of second pixels are with respect to a plurality of three differences and a plurality of four difference of these a plurality of the 3rd pixels with these a plurality of the 5th pixels, these a plurality of the 3rd pixels are with respect to a plurality of the 5th differences of these a plurality of the 6th pixels, these a plurality of the 4th pixels are with respect to a plurality of the 6th differences and the size of these a plurality of the 5th pixels with respect to a plurality of the 7th differences of these a plurality of the 6th pixels of these a plurality of the 5th pixels, if first difference is less with respect to a difference of the 3rd difference value, the 6th difference is less with respect to a difference of the 7th difference, second difference, the 4th difference and the 5th difference are all greater than one first standard value, then this image data is divided into one first block and one second block and in this first block and second block, gets one second standard value and one the 3rd standard value, this first block comprises this a plurality of first pixels, these a plurality of second pixels and these a plurality of the 3rd pixels, this second block comprises this a plurality of the 4th pixels, these a plurality of the 5th pixels and these a plurality of the 6th pixels;

This second standard value of complete storage and the 3rd standard value are in an internal memory;

Store these a plurality of first pixels and be worth in this internal memory with the ten worst individuals or units of this a plurality of the 3rd pixels with respect to one the 9th difference of this second standard value with respect to this second standard value with respect to one the 8th difference of this second standard value, these a plurality of second pixels, and store these a plurality of the 4th pixels with respect to 1 the 11 difference of the 3rd standard value, these a plurality of the 5th pixels with respect to 1 the 12 difference of the 3rd standard value and these a plurality of the 6th pixels with respect to 1 the 13 difference of the 3rd standard value in this internal memory;

Transmit on data to a main frame in this internal memory; And

Make up this data and be this image data.

10. scan compression as claimed in claim 9 is characterized in that than the method for differentiating automatically the second above-mentioned standard value is a mean value of these a plurality of first pixels, these a plurality of second pixels and these a plurality of the 3rd pixels.

Images