JPH08130629A - Image processor - Google Patents

Abstract

PURPOSE: To delete undesired part of image data and to minimize the quantity of image data after compression. CONSTITUTION: Image data are inputted to an image input means 1, and mask data representing an area of specific area image data in image data generated in other system or the like are inputted to a mask data input means 2. A deletion means 3 sets a circumscribed frame circumscribing a mask area in the mask data and deletes an undesired area other than the area surrounded by the circumscribed frame to generate reduced area image data whose quantity is reduced. A processing means 4 revises the reduced image data of the image area other than the mask area to be a prescribed value.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image processing apparatus, and more particularly to an image processing apparatus capable of reducing the amount of data when compressing image data.

[0002]

2. Description of the Related Art In a conventional image processing apparatus, a photograph in which a subject (for example, a product) is recorded together with a background is read by an image scanner or the like. The read image is captured by the image processing apparatus as image data 70, as shown in FIG. This image data 70 is
The subject image data 71 and the background image data (image data other than the subject image data 71) 72 are included.

Therefore, when it is desired to use only the image data of the subject portion, the mask data 73 is created in the image processing apparatus. This mask data 73 is also stored in the image processing apparatus. The mask data 73 is for extracting only the subject image data 71 as the specific area image data actually used for printing from the image data 70. Specifically, the mask data 73 has the same size as the image data, and each pixel is represented by binary data. Transparent and non-transparent are determined by these binary values. The image of the portion corresponding to the transparent portion is taken out in a state of being superimposed on the image data (a state in which the positions of both data correspond to each other), and No image is taken out. By doing so, only the image of the necessary portion can be taken out.

A terminal device is connected to the image processing apparatus. This terminal device is relatively simple and merely determines the layout of the image data 70 on the screen. The designer determines the layout of the image data 70 with this terminal device and reads the image data 70 stored in the image processing device. Next, the designer uses the terminal device to determine the layout of the image data 70, thereby designing the surface of a printed matter such as a catalog.

In the printing process, original data is created in accordance with the design determined by the designer. That is, in the image processing apparatus, only the subject image data 71 is extracted from the image data 70 using the mask data 73. According to the design determined by the designer, the extracted subject image data 71 is assigned to the original data. A printed matter is created based on the original data.

By the way, the background image data 72 is rarely used as original data for printing. Therefore, in the conventional image processing apparatus, storing all the input background image data 72 together with the subject image data 71 wastes the memory of the image processing apparatus. In particular, when the size of the background image data 72 is unnecessarily large, the background image data 72 may hinder the layout work of the subject in the terminal device.

Therefore, when the image data 70 is stored in the image processing apparatus, in the background image data 72, in the future,
The operator manually deleted the part that is not used (unnecessary part). A technique for automatically deleting these unnecessary portions using mask data is described in Japanese Patent Application Laid-Open No. 4-303812.

[0008]

However, in the image processing apparatus, the frame memory is used for storing the image data, and the image data is stored in m × n (m rows and n columns).
It is designed to be stored in a matrix of pixel arrangements. Therefore, since the image data is always saved in a rectangular shape even if the unnecessary area is removed, the subject image data 7
Except when 1 is a rectangle, the unnecessary area cannot be completely deleted, and unnecessary background image data 72 always remains. This is unavoidable due to the memory structure, but there is a problem that the amount of data after compression increases because there is extra image data when the image data is compressed and saved. It was That is, in order to store the image data in the storage medium more efficiently,
Although a compression process such as JPEG is often performed, the compression process must be performed on an unnecessary area, and unnecessary compressed image data will exist.

Therefore, the present invention provides an image processing apparatus,
An object of the present invention is to provide an image processing device capable of deleting unnecessary portions of image data and minimizing the amount of image data after compression.

[0010]

An image processing apparatus according to a first aspect of the present invention is directed to an image input unit 1 to which image data is input, and a specific area in the image data input to the image input unit. An image processing apparatus provided with mask data input means 2 for inputting mask data for extracting image data, further comprising processing means 4 for replacing an area other than the specific area image data with an arbitrary constant value. Is an image processing device.

The image processing apparatus according to the second aspect of the present invention is for extracting the image input means 1 into which the image data is input and the image data of the specific area in the image data input to the image input means. In the image processing apparatus including the mask data inputting means 2 to which the mask data is input, a circumscribing frame that circumscribes the mask area in the mask data is set, and image data of an unnecessary area outside the circumscribing frame is set from the image data. An image processing apparatus comprising: a deleting unit 3 for deleting and a processing unit 4 for replacing an area other than the specific area image data in the image data in which the unnecessary area is deleted with an arbitrary constant value.

An image processing apparatus according to a third aspect of the present invention is for extracting the image input means 1 into which image data is input and the image data of a specific area in the image data input to the image input means. In the image processing device including the mask data creating means 5 for creating the mask data, the circumscribing frame that circumscribes the mask area in the mask data is set, and the image data of the unnecessary area outside the circumscribing frame is set from the image data. An image processing apparatus comprising: a deleting unit 3 for deleting and a processing unit 4 for replacing an area other than the specific area image data in the image data in which the unnecessary area is deleted with an arbitrary constant value.

An image processing apparatus according to a fourth aspect of the present invention is the image processing apparatus according to the second or third aspect,
The deleting unit 3 is an image processing apparatus characterized by deleting a unnecessary area while leaving a correction area in the circumscribing frame.

An image processing apparatus according to a fifth aspect of the present invention, as shown in FIG. 1, is the image processing apparatus according to any one of the first to fourth aspects, wherein the image data processed by the processing means 4 is used. The image processing apparatus is characterized in that it is provided with a data compression means 5 for performing a compression process.

The mask area in the mask data means an area (74 in FIG. 8) corresponding to the specific area image data of the image data in the mask data.

[0016]

The image processing apparatus according to the first aspect of the invention is
Image data is input to the image input means 1. The mask data input means 2 inputs mask data indicating the area of the specific area image data in the image data created by another system or the like. The processing means 4 changes the image area other than the specific area to a predetermined constant value (its density data).

In the image processing apparatus according to the second aspect of the present invention, image data is input to the image input means 1. The mask data input means 2 inputs mask data indicating the area of the specific area image data in the image data created by another system or the like. The deleting unit 3 is a mask area in the mask data (area corresponding to the specific area of the image data).
Set a circumscribing frame to circumscribe. Furthermore, the deleting means 3
By deleting unnecessary areas other than the area surrounded by the circumscribing frame from the image data, reduced area image data with a reduced data amount is generated. With respect to the reduced image data, the processing unit 4 further changes the image area other than the specific area to a predetermined constant value (its density data).

In the image processing apparatus according to the third aspect of the invention, the image data is input to the input means 1. The mask data creating means 5 creates mask data indicating an area of the specific area image data in the image data according to an instruction from the operator. The deleting unit 3 sets a circumscribing frame that circumscribes a mask area (area corresponding to a specific area of image data) in the mask data 5. Further, the deleting unit 3 deletes unnecessary areas other than the area surrounded by the circumscribing frame from the image data to generate reduced area image data with a reduced data amount. For this reduced image data, the processing means 4 further changes the image area other than the mask area to a predetermined constant value (density data).

The image processing apparatus according to the invention of claim 4 deletes an unnecessary area while leaving a correction area in the circumscribing frame created by the deleting means 3.

In the image processing apparatus according to the fifth aspect of the present invention, the data compression means 6 compresses the data processed by the processing means 4.

According to the image processing apparatus of the first to fifth aspects, the data in the unnecessary area has a constant value. Therefore, if compression is performed using spatial frequency data such as JPEG, the compression rate is very high. It is possible to raise. Further, according to the image processing device of the present invention, it is possible to reduce the memory capacity occupied in the storage device by modifying the image data into reduced area image data in which unnecessary areas are deleted. You can

[0022]

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

The image processing apparatus according to this embodiment comprises a main frame including a CPU, a magneto-optical disk for storing image information, a display, a keyboard and the like. When this image processing apparatus is represented by a functional block diagram, this image processing apparatus is represented as shown in FIG.

In the block diagram shown in FIG. 2, the image input means 21 receives the image data 29. The image data 29 includes subject image data 30 representing a subject and background image data 31 representing a background portion other than the subject. The display means 25 is the display means 2
A predetermined image is displayed according to the data input in 5. The display means 25 corresponds to a display such as a CRT.

The mask data generating means 22 is for generating mask data 32 based on the image data 29 input to the image input means 21. This mask data 32
Is for extracting only the subject image data 30 from the image data 29. The generated mask data 32
Are written in the storage means 27 and displayed on the display means 25.

The deleting means 23 automatically executes a process of deleting an unnecessary portion of the background image data 31 from the image data 29 based on the mask data 32. The background image data 31 and the subject image data 30 from which unnecessary portions have been deleted form reduced area image data 33 whose data amount is reduced as compared with the original image data 29.

The processing means 24 uses the reduced area image data 33.
On the other hand, image data 34 in which a predetermined constant value (density data) is set in the image area other than the mask area is created.

The image compression means 26 is for subjecting the image data to JPEG compression processing to create compressed image data 35.

The storage means 27 reads and writes the mask data 32 and the compressed image data 35. The storage means 27 is composed of, for example, a magneto-optical disk or the like.

The image decompression means 28 is for producing the image data 34 'by subjecting the compressed image data 35 to a process reverse to that at the time of compression. However, this image data 34 ′ does not completely match the image data 34 because there is data that is deleted during compression processing.

Although not shown, a terminal device is connected to the image processing apparatus. This terminal device is relatively simple and can only determine the layout of the image data 29 on the screen. The designer reads the image data 29 stored in the image processing device from the terminal device and determines the layout of the image data 29 on the screen to design a printed matter such as a catalog.

Next, the operation of the image processing apparatus according to this embodiment will be described with reference to FIGS. FIG. 3 is a flow chart showing the operation of the image storage procedure.

First, the image data 29 to be input to this image storage device is prepared. The image data 29 is created according to the procedure shown in FIG. That is, the predetermined photograph 41
It is mounted on the surface of the drum 42 such as an image scanner. The drum 42 rotates about its axis. Then, a predetermined area of the photograph 41 mounted on the surface of the drum 42 is optically read. The read photograph 41 is input to the image processing apparatus as the image data 29 (step S3).
1).

Subsequently, mask data 32 is created based on the input image data 29 (step S32).
The mask data 32 is performed manually by an operator or by detecting a data level difference between the subject image data 30 and the background image data 31. The mask area 53 of the created mask data 32 is
The area of the subject image data 30 is shown. The mask data 29 is written in the storage means 27 in the image processing apparatus. The written mask data 32 is used as the subject image data 3 from the image data 29 in the subsequent printing process.
Used when extracting only 0s.

In the created mask data 32, the processing means 24 creates a rectangular circumscribing frame 51 shown in FIG. 5 (step S33). That is, the processing unit 24 generates the circumscribing frame 51 that is in contact with the area of the subject image data 30. Further, the four sides of the circumscribing frame 51 are multiplied by a predetermined magnification to create a new circumscribing frame 52 (step S3).
4). The area of the newly created circumscribing frame 52 is larger than that of the circumscribing frame 51. In this way, the circumscribing frame 5
The reason for creating the circumscribing frame 52 having an area larger than 1 is as follows. That is, the circumscribing frame 51 is set to the image data 2
9 and the image data 29 outside the range of the circumscribing frame 51.
It is assumed that the area of is deleted. In this case, the circumscribing frame 51 is in contact with a part of the subject image data 30, so that a part of the subject image data 30 may be deleted. In addition, a part of the background image data 31 outside the circumscribing frame may be used for correction or the like.

The deleting means 23 arranges the newly created circumscribing frame 52 on the image data 29. Next, processing means 2
In 4, the part of the background image data 31 other than the circumscribing frame 52 is regarded as an unnecessary part and the part is deleted. That is, as shown in FIG. 6, a part of the background image data 31 in the image data 29 is deleted, and the reduced area image data 33 is generated.

For example, if the unnecessary area of the image data of 100.times.100 pixels is deleted to obtain the data of 50.times.50 pixels, the amount of image data can be reduced to 1/4. However, the reduced area image data 33 still has an unnecessary area 36 that is not actually used.

Next, with respect to the reduced area image data 33, the processing means 24 sets a predetermined constant value for all pixels in the image area other than the mask area, for example, image data is Y (yellow), M (magenta), C (cyan), K (black)
When each color is represented by 256 gradations of 8 bits, (Y, M, C, K) = (255, 255, 255, 25
A white area 37 composed of the white data of 5) is set (step S35). In this way, the reduced area image data 34 in which the white area 37 is set is subjected to data compression using the JPEG algorithm (step S36). When the image is compressed by the JPEG method in this manner, the same data value is continuously formed in all the white areas 37, so that the step S3 is performed.
The compression ratio can be greatly increased as compared with the image not subjected to the process of No. 5. The compressed image data 35 created in this way is written in the storage means 27 (step S37).

The reason why the data compression rate of the white area 37 becomes high will be described with an outline of the JPEG compression method. First, the principle of JPEG compression processing will be briefly described with reference to FIGS. First, the image data is divided into 8 × 8 pixel blocks as shown in FIG. 9 and two-dimensional discrete cosine transform (hereinafter referred to as DCT) is performed. The resulting 8 × 8 pixel block data represents the frequency components of the image. The data at the upper left of this image data represents a DC (direct current) component, and the other data is AC.
It represents the (DC) component. Next, the obtained image data is quantized by a quantization matrix.

With respect to the quantized DCT output, a prediction error is obtained for the DC component using the DC component of the block on the left as a prediction value, and this is Huffman-encoded (DPCM processing). This is to compress data by assigning a short code to 0 or the like that has a high appearance frequency. On the other hand, for the AC component, as shown in FIG. 10, so-called zigzag scanning in which a component with a low frequency is connected to a component with a high frequency is performed, so that the data of the two-dimensional array is one-dimensionally arrayed. In normal image data, there is a high possibility that the high-frequency component will be zero, so the number of consecutive zeros is run-length compressed. Further, the data of the AC component is subjected to Huffman coding to assign a code suitable for the appearance probability, and the data is compressed.

In the above processing, if the DC components of adjacent 8 × 8 pixel blocks are the same as in the white area 37 of this embodiment, the prediction error becomes 0 and the compression rate of the DC component can be increased. it can. Further, since the AC component also does not exist, the data subjected to the zigzag scan is lined with 0s continuously, and the compression ratio by the above run length compression and Huffman coding can be increased, and the image at the time of compression as a whole. The amount of data can be small. When using compressed image data, the image decompression means 2
In step 8, the processing is reversed to the original (usable) state. As described above, according to the image processing apparatus according to the present embodiment, by setting the white area 37, the data amount can be reduced as compared with the case where the reduced area image data 33 is directly compressed.

Further, a designer or the like often works for product layout in a simple terminal device connected to the image processing apparatus. In a simple terminal device, handling the image data 29 having a large amount of data is extremely heavy. However, if the reduced area image data 34 read from the image processing apparatus is used in the product layout work, the load of the terminal device is reduced and the speed of image display, movement, etc. is increased due to the smaller data amount. It is possible to improve the efficiency of layout work.

Further, even when compressed image data is stored in the storage device of the terminal device, the image data can be stored more efficiently. In the above embodiment, (Y, M, C, K) = (255, 25)
However, the present invention is not limited to this, and an arbitrary constant value can be used. The types and formats of data to be handled are not limited to those described above, and needless to say, may be three primary color data of R (red), G (green), B (blue), and the like.

[0044]

According to the image processing apparatus of the present invention, the data in the unnecessary area has a constant value. Therefore, if compression is performed using spatial frequency data such as JPEG, it is extremely effective. It is possible to increase the compression rate. Further, according to the image processing device of the present invention, it is possible to reduce the memory capacity occupied in the storage device by modifying the image data into reduced area image data in which unnecessary areas are deleted. You can

[Brief description of drawings]

FIG. 1 is a block diagram showing a configuration of an invention according to the present invention by a function realizing means.

FIG. 2 is a block diagram showing an image processing apparatus according to an embodiment of the present invention.

FIG. 3 is a flowchart showing an operation of the image storage device according to the embodiment of the present invention.

FIG. 4 is a diagram showing a procedure for creating image data.

FIG. 5 is a diagram showing mask data and a circumscribing frame.

FIG. 6 is a diagram showing image data and a circumscribing frame.

FIG. 7 is a diagram illustrating image data and a white area.

FIG. 8 is a diagram illustrating image data, mask data, and subject image data according to a conventional image processing device.

FIG. 9 is a diagram illustrating JPEG processing blocks.

FIG. 10 is an explanatory diagram of JPEG zigzag scanning.

FIG. 11 is a flowchart showing the flow of JPEG processing.

[Explanation of symbols]

 21 image input means 22 mask data creating means 23 deleting means 24 processing means 29 image data 30 subject image data (specific area image data) 32 mask data 33 reduced area image data 37 white area

Front page continuation (72) Inventor Morinatsu Matsuyama 1-5-1, Taito, Taito-ku, Tokyo Toppan Printing Co., Ltd. Within the corporation

Claims (5)

[Claims] 1. Image input means for inputting image data, mask data input means for inputting mask data for extracting image data of a specific region in the image data input to the image input means, An image processing apparatus comprising: an image processing apparatus including processing means for replacing an area other than the specific area image data in the image data with an arbitrary constant value. 2. Image input means for inputting image data, mask data input means for inputting mask data for extracting image data of a specific region in the image data input to the image input means, In the image processing apparatus including, a circumscribing frame that circumscribes the mask area in the mask data is set, and a deleting unit that deletes image data of an unnecessary area outside the circumscribing frame from the image data, and the unnecessary area is deleted. An image processing apparatus comprising a processing means for replacing an area other than the specific area image data in the image data with an arbitrary constant value. 3. Image input means for inputting image data, mask data creation means for creating mask data for extracting image data of a specific region in the image data input to the image input means, In the image processing apparatus including, a circumscribing frame that circumscribes the mask area in the mask data is set, and a deleting unit that deletes image data of an unnecessary area outside the circumscribing frame from the image data, and the unnecessary area is deleted. An image processing apparatus comprising a processing means for replacing an area other than the specific area image data in the image data with an arbitrary constant value. 4. The image processing apparatus according to claim 1, wherein the deleting unit deletes an unnecessary area while leaving a correction area in the circumscribing frame. 5. The image processing apparatus according to claim 1, further comprising a data compression unit that compresses the image data processed by the processing unit.