JP2002290242A - Image processor, image processing method, computer program and storage medium for storing the computer program - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an image processing unit by which coded data of an original image can be efficiently stored to a storage medium with a limited data capacity within a range of deteriorated image quality at which the decoded image can be identified as the original image. SOLUTION: When a data quantity of the coded data generated by discrete wavelet conversion is greater than the capacity of the storage medium, the processing of eliminating the coded data by each sub band is recursively conducted from a high frequency component toward a low frequency component until the remaining data quantity becomes smaller than the capacity of the storage medium.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a field of an image processing apparatus for encoding image data and storing the encoded image data on a storage medium such as a floppy (registered trademark) disk.

[0002]

2. Description of the Related Art Conventionally, digital image data (hereinafter, referred to as digital image data)
In the field of image processing that handles image data), when storing and transmitting image data (especially multi-valued image data),
The size of the data becomes a problem.

For this reason, such image data storage and storage
At the time of transmission, the data included in the image data of the original image is eliminated by eliminating redundancy included in the image data of the original image, or by changing the content of the image data of the original image to such an extent that deterioration of the image quality is hardly recognized by human eyes. High-efficiency coding (compression) to reduce the amount
Is used. As a compression (encoding) method of an input still image, JPEG (Jois) using discrete cosine transform is used.
nt Photographic Experts Group) and a method using wavelet conversion are widely used.

A file of image data compressed by an image processing apparatus in accordance with these methods is a data file which is considerably compact as compared with the original data size before compression, so that handling in data transmission is relatively easy. Becomes

[0005]

However, the image data file compressed by the image processing apparatus as described above is copied (generated) or copied (generated) in an external storage medium (recording medium) by an operation such as copying by an operator. When moving, especially when the storage medium to be used is portable such as a floppy disk (FD) or Zip, the amount of data that can be stored is limited. However, since the file has a data amount exceeding a predetermined data capacity of the storage medium, the file cannot be copied or moved in many cases.

Accordingly, the present invention provides an image processing apparatus for efficiently storing encoded data of an original image on a storage medium having a limited data capacity within a range of image quality deterioration in which a user can identify a restored image as an original image. , An image processing method, a computer program, and a storage medium storing the computer program.

[0007]

To achieve the above object, an image processing apparatus according to the present invention has the following configuration.

That is, a comparison is made by comparing the data amount of coded data composed of a plurality of frequency components generated in advance by coding image data of an original image with a data storage capacity allowed for a predetermined storage medium. Means, and storage control means for storing the encoded data in the storage medium based on the comparison result by the comparing means, wherein the storage control means determines that the data amount of the encoded data is stored by the comparing means. When it is determined that the capacity is larger than the storage capacity of the medium, a part of the encoded data is deleted, and the remaining encoded data is stored in the storage medium.

In a preferred embodiment, when deleting a part of the coded data, the accumulation control means preferably deletes the high-frequency component data of the coded data with priority.

In this case, for example, when the comparing means determines that the data amount of the remaining encoded data from which the high-frequency component data has been deleted is larger than the storage capacity of the storage medium, The process of sequentially deleting data from the remaining encoded data in order from high frequency components to low frequency components is performed recursively until it is determined that the data amount of the encoded data after deletion is smaller than the storage capacity of the storage medium. Good to repeat.

For example, when a plurality of coded data are to be stored corresponding to a plurality of original images, the storage control means performs a process of sequentially deleting the same frequency component of the coded data. Until it is determined that the total data amount of the coded data after the deletion is smaller than the storage capacity of the storage medium, it is preferable to repeat recursively from high frequency components to low frequency components.

Alternatively, corresponding to a plurality of original images,
When a plurality of coded data are to be stored, the storage control means performs a process of deleting all the same frequency components of the coded data, and the total data amount of the coded data after the deletion is stored in the storage medium. It is preferable to repeat recursively from high frequency components to low frequency components until it is determined that the capacity is smaller than the capacity.

In each of the above device configurations, if the encoded data corresponding to the original image is encoded data composed of a plurality of frequency component level subbands generated by discrete wavelet transform, the accumulation control means When preferentially deleting high-frequency component data of encoded data, it is preferable to delete the data in units of subbands of the target frequency component level.

The above-mentioned object is achieved by a program code for realizing the operation of the image processing apparatus of each of the above-described apparatus by a computer, a computer-readable storage medium storing the program code, and a computer-readable storage medium. The present invention is also achieved by an image processing method corresponding to an image processing device having each device configuration.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of an image processing apparatus according to the present invention will be described below in detail with reference to the drawings.

In each of the embodiments described below,
As image data (multi-valued image data) to be encoded in a still image, 8-bit monochrome image data is handled as an example. However, the present invention provides for each pixel 4 bits, 10 bits.
A monochrome image in which each pixel is represented by a bit number other than 8 bits such as 12 bits, or color multi-valued image data in which each color component (RGB / Lab / YCrCb) in each pixel is represented by 8 bits. Applicable in some cases. In addition, in the case of multi-value information indicating the state of each pixel constituting an image to be encoded, the present invention can be applied to, for example, a case of a multi-value index value indicating the color of each pixel. When the present invention is applied to such color image data, each type of multi-value information may be handled as monochrome image data in each embodiment described below.

[First Embodiment] FIG. 1 is a block diagram showing the configuration of an image processing apparatus according to a first embodiment.

In the image processing apparatus 10 shown in FIG.
Reference numeral 1 denotes an image data encoding unit, 02 denotes an image encoded data storage unit, 03 denotes a generation target image encoded data designation unit, and 04 denotes a generated image encoded data determination unit. The accumulation of the image data in the memory 11 is controlled by the CPU 100.

The input interface of the input image data to the image processing apparatus 10 and the input / output interface between the image processing apparatus 10 and the storage medium 11 can be general interfaces. And the expression in FIG. 1 will be omitted.

Here, the outline of the operation of the image processing apparatus 10 will be described with reference to FIG.

FIG. 10 is a flowchart showing the schematic operation of the image processing apparatus according to the first embodiment, in which input image data (original image) is encoded and then stored in the storage medium 11 as encoded image data. The schematic procedure up to this point is shown. Such an overall operation is controlled by the CPU 100.

In FIG. 1 and FIG.
The 8-bit monochrome multivalued image data (input image data) externally input to 0 is encoded by the image data encoding unit 01 based on a predetermined encoding method (steps S1 and S2). In the present embodiment, the image data encoded by the image data encoding unit 01 is
This is referred to as “image encoded data”.

The encoded image data generated by the image data encoding unit 01 is stored as a data file in the encoded image data storage unit 02 (step S3).

In a state where the data file of the encoded image data is stored in the encoded image data storage unit 02, the user (operator) of the image processing apparatus 10 stores the image file by the function of the generation target image encoded data specifying unit 03. A file of desired image encoded data to be generated (stored) in the medium 11 can be designated (step S4: see FIG. 6).

When a file of desired encoded image data to be generated (stored) in the storage medium 11 is specified, the generated image encoded data determination unit 04 determines the current data size of the specified data file, In consideration of the storable capacity of the storage medium 11, the entirety or a part of the designated image encoded data is stored in the storage medium 1 having a data size within the storable capacity range.
1 is stored (generated) in the storage medium as "encoded image data to be generated" (step S5).

Hereinafter, a description will be given of processing from the generation of encoded image data by the image data encoding unit 01 to the accumulation of the generated encoded image data in the encoded image data storage unit 02. After the description, the processing in the generation target image encoded data specifying unit 03 and the image encoded data determining unit 04 will be described.

<Image Data Encoding Unit 01, Image Encoded Data Storage Unit 02> FIG. 2 is a block diagram showing the configuration of the image data encoding unit 01 in the first embodiment. It comprises a wavelet transform unit 202, a buffer 203, a coefficient quantization unit 204, an entropy encoding unit 205, and an encoded image data output unit 206.

Referring to FIG. 1, multi-valued pixel data constituting input image data (8-bit monochrome multi-valued image data) to be encoded is input to an image input unit 201 in raster-scan order. You. The image input unit 201 includes, for example, an imaging device such as a scanner or a digital camera, or a CC.
An imaging device such as D (charge-coupled device) or an interface of a network line is used. Further, the image input unit 201 may be a recording medium such as a RAM, a ROM, a hard disk, and a CD-ROM.

The discrete wavelet transform unit 202 performs a discrete wavelet transform process on the image data input as described above. That is, the discrete wavelet transform unit 202 performs a discrete wavelet transform on each pixel data of one screen output from the image input unit 201, and outputs a discrete wavelet coefficient generated as a result to a plurality of frequency bands. (Sub-band). In the present embodiment, the discrete wavelet transform processing for the image data sequence x (n) is performed based on the following equation.

R (n) = floor {(x (2n) + x (2n + 1)) / 2} (1), d (n) = x (2n + 2) -x (2n + 3) + floor} (-r (N) + r (n + 2) +2) / 4} (2), where, in the above equations (1) and (2), r
(N) and d (n) are conversion coefficients, r (n) is a low frequency subband, and d (n) is a high frequency subband. Further, in the above equations (1) and (2), floor
{X} represents the maximum integer value not exceeding X.

This conversion formula is for one-dimensional data. By performing this conversion process sequentially in the horizontal and vertical directions to perform two-dimensional conversion, the conversion formula is as shown in FIG. It can be divided into four subbands LL, HL, LH, HH as shown. Here, L indicates a low frequency sub-band, and H indicates a high frequency sub-band.

Next, among the four sub-bands shown in FIG. 3A, the LL sub-band is divided into four sub-bands by the same two-dimensional conversion as described above (see FIG. 3B).
The LL subband obtained by the conversion is further divided into four subbands (see FIG. 3C). This allows
As shown in FIG. 3C, HH1, HL1,...
0 subbands are obtained.

In the present embodiment, the number in the name of each subband is the level (frequency component level) of each subband. That is, the level 1 subbands are HL1, HH1, LH1, and the level 2 subbands are HL2, HH2, LH2. The LL sub-band is a level 0 sub-band.

The decoded data obtained by decoding the sub-bands up to level n is referred to as level n decoded data. The decoded image obtained from the level n decoded data is called a level n decoded image.

The decoded image has a higher resolution as the numerical value n of the level n is larger. Decoded data obtained by decoding all subbands is called complete decoded data. A decoded image obtained by displaying the completely decoded data on the image display device is referred to as a completely decoded image.
In the present embodiment, as described above, the sub-band shown in FIG. 3C is generated by repeating the two-dimensional conversion three times. It is.

In this embodiment and other embodiments described later, the image coded data transmitted to the decoding device is:
It is assumed that there are ten subbands as described above.

Next, the buffer 203 temporarily stores the ten subbands output from the discrete wavelet transform unit 202. The buffer 203 stores the ten temporarily stored subbands in LL, HL1, LH1, HH1, HL2,
In the order of LH2, HH2, HL3, LH3, HH3,
The sub-bands are output to the coefficient quantization unit 204 in order from the sub-band having the lower level to the sub-band having the higher level.

The coefficient quantization unit 204 quantizes each sub-band read from the buffer 203. That is, the coefficient quantization unit 204 quantizes the wavelet transform coefficients of each subband output from the buffer 203 in a predetermined quantization step (see FIG. 4) for each frequency component.
The value after quantization (coefficient quantization value) is output to entropy encoding section 205.

FIG. 4 is a diagram showing a correspondence between each frequency component and a quantization step in the first embodiment. As shown in FIG. 4, as shown in FIG. HL1, LH1, HH1, etc.) are given larger quantization steps.

In this embodiment, the quantized coefficient value Q
(X) is obtained by the following equation.

Q (X) = floor {(X / q) +0.5} (3) where, in equation (3), the coefficient value is X, and the quantization step for the frequency component to which the coefficient belongs. Is q.
In the equation (3), floor {X} represents the maximum integer value not exceeding X.

After quantizing all the coefficients in one sub-band, coefficient quantizing section 204 outputs the resulting quantized coefficient value to entropy encoding section 205.

The entropy encoding unit 205 generates an entropy encoded value by entropy encoding the input coefficient quantization value by arithmetic encoding.
The generated entropy encoded value is output to the encoded image data output unit 206.

The encoded image data output section 206 arranges the input entropy encoded values in subband units and adds a header to the head of the encoded entropy values as shown in FIG. Generate
Then, the generated image encoded data is stored in the image encoded data storage unit 02 as one data file. The coded image data storage unit 02 stores FD and Z
In general, a hard disk device or the like having a larger storage capacity than the storage medium 11 such as an ip is assumed.

The header of the encoded image data includes information such as the size of the image input to the image input unit 201, an image type indicating whether the image is a binary image or a multi-valued image, and the transmission. Information such as a character string indicating the image encoding / transmission device to be transmitted and the transmission date and time is written.

<Generation target image coded data designating unit 03,
Image Encoded Data Determination Unit 04> Next, the operations of the generation target image encoded data specification unit 03 and the image encoded data determination unit 04 will be described.

FIG. 11 is a flowchart showing the process of deleting the encoded image data in the first embodiment. The image encoding data specifying unit 03 and the encoded image data determining unit 04 operate to delete the image encoded data. Data storage unit 0
2 shows a procedure until the image coded data stored in the storage medium 2 is stored as generated image coded data having a data size that can be stored (generated) in the storage medium 11. Such an overall operation is controlled by the CPU 100.

In a state where the file of the image encoded data is stored in the image encoded data storage unit 02 as described above, the user of the image processing apparatus 10 transmits data (equivalent to the stored file of the image encoded data). That is, when it is desired to generate the generated image encoded data including all or a part of the image encoded data in the storage medium 11, the user can attach and detach the storage medium 11 to be used to the image processing apparatus 10. In this case, the storage medium is connected to the coded image data storage unit 02, and the file of the desired coded image data to be generated is specified by the function of the coded image data specifying unit 03 (step S500). . As an example of the operation in this case, as illustrated in FIG.
Is an information processing device (computer) 1 such as a general personal computer, the image encoded data storage unit 02 is operated by the function of the generation target image encoded data specifying unit 03.
Is displayed on the display 2 and a user designates a desired icon using a pointing device such as a mouse, thereby designating desired image encoded data. A method is conceivable.

In this embodiment, the image processing apparatus 1
0 handles one image coded data. In addition, the specification of the desired encoded image data to be generated is not limited to manual operation by the user.

When the coded image data to be generated is specified by the function of the coded image data to be generated specifying unit 03, the coded image data to be generated determining unit 04 determines the data amount of the coded image data (the image data to be generated). The amount of encoded data: that is, the data size in the state of being stored as a data file in the image encoded data storage unit 02) is calculated, and the amount of data and the currently storable capacity of the storage medium 11 (allowable for the medium) (Hereinafter, simply referred to as “capacity of storage medium 11”).
Are compared (step S501).

As a result of the comparison in step S501, if the capacity of the storage medium 11 is larger than the amount of the encoded image data to be generated, the encoded image data to be generated is stored in the storage medium 11 with the same data size. Since it is possible, all of the encoded image data is determined as data to be generated in the storage medium 11 (step S502). Then, the generated image encoded data is moved or copied into the storage medium 11 by the copy or move process (step S506).

On the other hand, as a result of the comparison in step S501, when the capacity of the storage medium 11 is smaller than the amount of the encoded image data to be generated, the encoded image data to be generated is stored in the storage medium 11 with the same data size.
It is impossible to accumulate. Therefore, in the present embodiment, the data amount of the encoded image data to be generated is reduced as described below so as to fit in the limited storage capacity of the storage medium 11.

FIG. 7 is a diagram for explaining the process of storing the encoded image data in the first embodiment.

As described above with reference to FIG. 3 (c), the encoded image data to be generated in the state where the encoded image data is stored in the image encoded data storage unit 02 as a data file generates a completely decoded image from the decoded image. Although it is possible full set data, in the present embodiment, step S50
As a result of the comparison in step 1, when it is determined that the data cannot be stored as it is, as shown in FIG. 7A, the sub-band HH3 indicating the highest frequency component in the image encoded data is deleted. Thereby reducing the data amount (step S503).

If it is determined by the determination in step S504 that the remaining data amount is larger than the capacity of the storage medium 11 even after such data deletion, as shown in FIG. Subsequent to HH3, the sub-band HL3 indicating a high-frequency component is deleted (step S503).

The data deletion processing in step S503 and the comparison processing of the data amount after deletion in step S504 are performed in order from the subband of the high frequency component to the subband of the low frequency component. The process is performed recursively until the capacity of the storage medium 11 becomes smaller.

If the data amount after deletion is smaller than the capacity of the storage medium 11 as a result of the determination in step S 504, the encoded image data at that point is generated image encoding data to be stored in the storage medium 11. The data is determined (step S505). Then, the generated image encoded data is moved or copied into the storage medium 11 by the copy or move process (step S506).

In the above-described first embodiment, when the data amount of the encoded image data to be accumulated (stored) is larger than the capacity of the storage medium 11, the sub-band of the high frequency component of the encoded image data is shifted to the low frequency band. The data amount is reduced by sequentially deleting one by one toward the component subbands. For this reason, the image obtained by decoding the generated image encoded data merely represents the outline of the decoded image obtained from the image encoded data before being deleted.

However, by performing the code amount control for preferentially deleting the high frequency component from the sub-band as in the present embodiment, although the completely decoded image cannot be obtained in the decoded image, the user can use the restored image as the original image. The encoded data of the original image can be efficiently stored in the storage medium 11 having a limited data capacity within the range of the identifiable image quality deterioration.

[Second Embodiment] Next, a second embodiment based on the image processing apparatus according to the first embodiment will be described. In the following description, the same configuration as that of the first embodiment will not be described repeatedly, and the description will focus on the characteristic portions of the present embodiment.

In the first embodiment described above, only one piece of encoded image data is generated in the storage medium 11. In the present embodiment, the storage medium 11 generates a plurality of encoded image data.

When input image data is input to the image processing apparatus according to the present embodiment, the image data is generated in the image data encoding unit 01 and the encoded image data is stored in the image data encoding unit, as in the first embodiment. 02. Then, in the generation target image encoded data specifying unit 03, the user specifies the desired image encoded data to be generated. However, there are a plurality of designated image encoded data files.

Also in the present embodiment, the processing procedure for storing the encoded image data by the encoded image data specifying unit 03 and the encoded image data determining unit 04 is as follows.
This is substantially the same as the flowchart shown in FIG. 11 in the first embodiment, except that steps S503 and S50
4 is characterized by the recursive data amount deletion processing. This will be described with reference to FIG.

FIG. 8 is a diagram for explaining a process of deleting image encoded data according to the second embodiment. FIG. 8 shows a case in which a user has designated four desired image encoded data files. .

If it is determined in step S501 that the data amount of the encoded image data to be generated is larger than the capacity of the storage medium 11, in the present embodiment, a plurality of image encoding data designated in step S500 is determined. Of the data, the subband HH3 of the highest frequency component in any one of the encoded image data is deleted, and the data amount of the encoded image data is reduced (step S503). In the example shown in FIG. 8A, the sub-band HH3 is deleted from the upper left coded image data targeted for data reduction among the four coded image data specified by the user.

If the total data amount of the specified plurality of encoded image data is larger than the capacity of the storage medium 11 even after the deletion (step S504), this time, a different one from the above-described image encoded data is used. The sub-band HH3 of the image encoded data is deleted, and the data amount of the image encoded data is reduced (step S503). FIG.
In the example shown in (b), a sub-band HH3 is newly added from the upper right image coded data which is the data reduction target this time among the four image coded data specified by the user.
Has been removed.

Even if all the sub-bands HH3 are deleted from the specified plurality of encoded image data, if the total data amount of the specified plurality of encoded image data is larger than the capacity of the storage medium 11, Then, similar deletion processing is recursively repeated focusing on the subband HL3.

As described above, in the present embodiment, the total data amount of the specified plurality of encoded image data is
As described above, from the high-frequency component sub-band to the low-frequency component sub-band, the sub-bands at the same level of the plurality of pieces of image encoded data are determined until it is determined in step S 504 that the capacity is smaller than the capacity of the storage medium 11. The data amount is reduced by sequentially deleting the bands one by one.

As another method for specifying the order of images in which subbands of the same type are to be deleted, a natural image having few edges is deleted first, and then a character image having many edges is deleted. May be adopted.

As a result, according to the present embodiment, the same effects as those of the first embodiment can be obtained, and further, the user can convert the encoded image data of a plurality of original images to be stored into a restored image. It can be efficiently stored in the storage medium 11 having a limited data capacity within a range of image quality degradation that can be identified as "."

[Third Embodiment] Next, a third embodiment based on the image processing apparatus according to the first embodiment will be described. In the following description, the same configuration as that of the first embodiment will not be described repeatedly, and the description will focus on the characteristic portions of the present embodiment.

In the first and second embodiments described above, in the process of reducing the encoded image data to be generated,
One image coded data is sequentially deleted from subbands of high frequency components, or a plurality of image coded data is sequentially deleted from subbands of the same level of high frequency components. Such a method is used when the capacity of the storage medium 11 is very small (small) or when the data size of the image coding data to be generated is extremely large, and the generated image coding data stored in the storage medium 11 in step S505 is used. It is expected that it will take some time before is determined.

Therefore, in the present embodiment, as in the second embodiment described above, a plurality of image encoded data are targeted, but when deleting subbands, all image encoded data specified by the user are deleted. In the data, the data is deleted in units of target subbands of the same level.

FIG. 9 is a diagram for explaining a process of deleting image encoded data in the third embodiment. FIG.
13 is a flowchart of a process of storing image encoded data according to the third embodiment.

Also in the present embodiment, the processing procedure of the storage processing of the image coded data by the generation target image coded data specifying unit 03 and the image coded data determination unit 04 is the same as that of the first and second embodiments shown in FIG. Is substantially the same as the flowchart shown in FIG. 19, but is characterized in the step S503 of deleting the data amount.

That is, if it is determined in step S501 that the total data amount of a plurality of (four in the present embodiment) image encoded data to be generated is larger than the capacity of the storage medium 11, Step S
In 503B, first, as shown in FIG. 9A, the subbands H of the same level of all the target image encoded data
Delete all H data.

Then, even if all of the sub-bands HH3 are deleted from the designated plurality of encoded image data, the total data amount of the designated plurality of encoded image data is larger than the capacity of the storage medium 11 ( Step S50
Next, similar deletion processing is performed on the sub-band HL3 to focus on the sub-band HL3, and as shown in FIG.
Delete all L3 data.

As described above, in the present embodiment, the total data amount of the designated plurality of encoded image data is
As described above, from the high-frequency component sub-band to the low-frequency component sub-band, the sub-bands at the same level of the plurality of pieces of image encoded data are determined until the capacity of the storage medium 11 is determined to be smaller than the capacity of the storage medium 11 in step S 504. The data amount is reduced by deleting all bands at once.

Thus, according to the present embodiment, the coded image data of a plurality of original images to be stored can be stored in a limited data capacity within a range of image quality degradation in which the user can identify the restored image as the original image. It is possible to efficiently store the data in the storage medium 11 more quickly than in the second embodiment.

In each of the above-described embodiments, the coded image data is deleted in units of subbands, but may be deleted in units of other data. As a data unit in this case, for example, the operation is performed in units of bit planes in a subband.

[0081]

[Other Embodiments] The present invention can be applied as a part of a system constituted by a plurality of devices (for example, a host computer, an interface device, a reader, a printer, etc.). One device (eg, copier, digital camera, etc.)
May be applied to a part of the device composed of:

The present invention is not limited to only the apparatus and method for realizing each of the above embodiments,
Within the scope of the present invention, a computer (CPU or MPU) in the above system or apparatus is provided with software program codes for realizing the above embodiment,
The case where the computer of the system or the apparatus operates the various devices according to the program code to realize the above-described embodiments is also included.

In this case, the program code pertaining to the software implements the functions of the above-described embodiments, and the program code itself and the program code are supplied to the computer. Means for performing the above, specifically, a storage medium storing the above-mentioned program code are included in the scope of the present invention.

As storage media for storing such program codes, for example, floppy disks, hard disks, optical disks, magneto-optical disks, CD-ROMs, magnetic tapes, nonvolatile memory cards, A ROM or the like can be used.

The computer controls the various devices according to only the supplied program codes, so that the functions of the above-described embodiments are realized. Even when the above embodiments are realized in cooperation with an OS (operating system) running on a computer or other application software, the program code according to the present invention is also applicable to the present invention. Included in the category.

Further, after the supplied program code is stored in a function expansion board of a computer or a memory provided in a function expansion unit connected to the computer, the program code of the program code is stored. The present invention also includes a case where the CPU or the like provided in the function expansion board or the function expansion unit performs part or all of the actual processing based on the instruction, and the above-described embodiments are realized by the processing. included.

[0087]

According to the above-described present invention, the encoded data of the original image is stored in a storage medium having a limited data capacity within a range of image quality deterioration in which the user can identify the restored image as the original image. It is possible to provide an image processing apparatus, an image processing method, a computer program, and a storage medium storing the computer program that efficiently accumulate.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating a device configuration of an image processing device according to a first embodiment.

FIG. 2 is an image data encoding unit 0 according to the first embodiment.
1 is a block diagram showing a configuration of FIG.

FIG. 3 is a diagram illustrating a procedure of a discrete wavelet transform according to the first embodiment.

FIG. 4 is a diagram showing a correspondence between each frequency component and a quantization step in the first embodiment.

FIG. 5 is a diagram illustrating a configuration of encoded image data output from an encoded image data output unit 206 according to the first embodiment.

FIG. 6 is a diagram exemplifying a method of specifying encoded image data by a generation target image specifying unit 03;

FIG. 7 is a diagram illustrating a process of deleting encoded image data according to the first embodiment.

FIG. 8 is a diagram illustrating a process of deleting encoded image data according to the second embodiment.

FIG. 9 is a diagram illustrating a process of deleting encoded image data according to the third embodiment.

FIG. 10 is a flowchart illustrating a schematic operation of the image processing apparatus according to the first embodiment.

FIG. 11 is a flowchart of a process of storing encoded image data according to the first embodiment.

FIG. 12 is a flowchart of a process of storing encoded image data according to the third embodiment.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) H04N 7/30 H04N 7/133 Z F term (Reference) 5C053 FA08 FA23 GA11 GB22 GB26 GB32 GB36 KA24 LA01 5C059 MA00 MA24 MC11 MC38 ME01 PP01 SS15 SS20 TA39 TB15 TC15 TD11 TD17 UA02 UA15 5C078 AA04 BA53 CA01 CA14 CA27 5D044 AB07 BC01 CC05 DE04 EF03 EF05 GK08 GK12 5J064 AA02 BA09 BA16 BC01 BC02 BC16 BD02

Claims (18)

[Claims] 1. A comparison for comparing the data amount of encoded data composed of a plurality of frequency components generated in advance by encoding image data of an original image with a data storage capacity allowed for a predetermined storage medium. Means, and storage control means for storing the encoded data in the storage medium based on the comparison result by the comparing means, wherein the storage control means stores the encoded data in the storage medium by the comparing means. An image processing apparatus characterized in that when it is determined that the storage capacity of a medium is larger, a part of the encoded data is deleted and the remaining encoded data is stored in the storage medium. 2. The image processing apparatus according to claim 1, wherein said storage control means, when deleting a part of said encoded data, preferentially deletes high-frequency component data of said encoded data. . 3. The storage control means, when the comparing means determines that the data amount of the remaining encoded data from which the high-frequency component data has been deleted is larger than the storage capacity of the storage medium, A process of sequentially deleting data from coded data in order from high-frequency components to low-frequency components is recursively repeated until it is determined that the data amount of the coded data after deletion is smaller than the storage capacity of the storage medium. The image processing apparatus according to claim 2, wherein: 4. When a plurality of coded data are to be stored corresponding to a plurality of original images, the storage control means deletes the process of sequentially deleting the same frequency component of the coded data. 4. The image processing according to claim 3, wherein repetitive repetition is performed from high-frequency components to low-frequency components until it is determined that the total data amount of subsequent encoded data is smaller than the storage capacity of the storage medium. apparatus. 5. When a plurality of coded data are to be stored corresponding to a plurality of original images, the storage control means performs a process of deleting all the same frequency components of the coded data. Until the total data amount of the encoded data is determined to be smaller than the storage capacity of the storage medium,
4. The image processing apparatus according to claim 3, wherein recursive repetition is performed from high-frequency components to low-frequency components. 6. The encoded data corresponding to the original image,
Coded data comprising a plurality of frequency component level sub-bands generated by the discrete wavelet transform, wherein the storage control means selects a target frequency when deleting preferentially from high-frequency component data of the coded data. The image processing apparatus according to claim 2, wherein data is deleted in subband units at a component level. 7. An image encoding unit that divides image data of the original image into a plurality of frequency band coefficients and encodes the coefficients to generate encoded data corresponding to the original image. The image processing device according to claim 1, further comprising: 8. The image encoding means recursively divides image data of the original image into coefficients in a plurality of frequency bands from a high frequency band to a low frequency band by a discrete wavelet transform. The image processing apparatus according to claim 7, wherein: 9. A comparison for comparing the data amount of encoded data composed of a plurality of frequency components generated in advance by encoding image data of an original image with a data storage capacity allowed for a predetermined storage medium. And a storage control step of storing the encoded data in the storage medium based on the comparison result in the comparison step. In the storage control step, the data amount of the encoded data is reduced in the comparison step. An image processing method, wherein when it is determined that the storage capacity is larger than the storage medium, a part of the encoded data is deleted and the remaining encoded data is stored in the storage medium. 10. The image processing method according to claim 9, wherein, in the accumulation control step, when deleting a part of the encoded data, the encoded data is preferentially deleted from high frequency component data of the encoded data. . 11. The storage control step, when it is determined in the comparison step that the data amount of the remaining encoded data from which the high-frequency component data has been deleted is larger than the storage capacity of the storage medium, A process of sequentially deleting data from coded data in order from high-frequency components to low-frequency components is recursively repeated until it is determined that the data amount of the coded data after deletion is smaller than the storage capacity of the storage medium. The image processing method according to claim 10, wherein: 12. When a plurality of encoded data are to be stored corresponding to a plurality of original images, the storage control step includes:
The process of sequentially deleting the same frequency components of the encoded data is performed from the high frequency components to the low frequency components until it is determined that the total data amount of the encoded data after the deletion is smaller than the storage capacity of the storage medium. 12. The image processing method according to claim 11, wherein the image processing is repeated recursively. 13. When a plurality of coded data are to be stored corresponding to a plurality of original images, the storage control step includes:
The process of deleting all the same frequency components of the encoded data is performed from the high frequency component to the low frequency component until it is determined that the total data amount of the encoded data after the deletion is smaller than the storage capacity of the storage medium. 12. The image processing method according to claim 11, wherein recursive repetition is performed. 14. The coded data corresponding to the original image is coded data composed of a plurality of frequency component level subbands generated by a discrete wavelet transform. 14. The image processing method according to claim 10, wherein data is deleted in units of sub-bands of a target frequency component level when data is preferentially deleted from high-frequency component data. 15. A computer program comprising a program code for operating a computer as the image processing apparatus according to claim 1. Description: 16. A computer program comprising a program code capable of realizing the image processing method according to claim 9 in a computer. 17. A computer-readable storage medium storing a program code for operating a computer as the image processing apparatus according to claim 1. Description: 18. A computer-readable storage medium storing a program code capable of realizing the image processing method according to claim 9 in a computer.