WO2013172207A1

WO2013172207A1 - Digital comics data compression device, method, and program

Info

Publication number: WO2013172207A1
Application number: PCT/JP2013/062750
Authority: WO
Inventors: 敏貢福島
Original assignee: 富士フイルム株式会社
Priority date: 2012-05-17
Filing date: 2013-05-02
Publication date: 2013-11-21
Also published as: JP5977342B2; JPWO2013172207A1

Abstract

A digital comics data compression device includes: a data acquisition means (12) for acquiring digital comics data that includes page images of a plurality of pages of comics; a compression order determination means (128) (information acquisition means) for acquiring at least one of the number of frames and a balloon area in each page of the page images of the plurality of pages in the digital comics data; a data compression means (122) capable of compressing the page images in the digital comics data in units of pages; a data size calculation means (124) for calculating the total data size of the digital comics data after the compression by the data compression means (122); and a compression control means (130) for increasing, when the total data size calculated by the data size calculation means (124) is larger than a target value, the compression ratio of a page image selected on the basis of at least one of the number of frames and the balloon area in each page, among the page images of the plurality of pages in the digital comics data, and for making the data compression means (122) compress the selected page image again.

Description

Electronic comic data compression apparatus, method and program

The present invention relates to an electronic comic data compression apparatus, method, and program for performing data compression of electronic comic data.

When distributing electronic comic data to mobile terminals such as mobile phones and smartphones, each page image included in the huge electronic comic data is appropriately sized so that the comics can be viewed comfortably even in a small display area of the mobile terminal. The image size (vertical and horizontal size) is adjusted to an appropriate total data size (file capacity).

In Patent Document 1, the image file size is reduced by a predetermined ratio, and when the image format is changed, the image file is repeatedly changed until the data size of the image file reaches a target value. A configuration is disclosed.

Patent Document 2 discloses a configuration for calculating the compression rate from the image width, height, file size, and the like written in the header in the case of lossy compression.

Patent Document 3 discloses a configuration in which an image of data having a small image size is prevented from being deteriorated as much as possible by compressing only a file having a predetermined image size or larger.

Patent Document 4 discloses a configuration in which an actual page image is taken in for each page and is compressed and encoded.

Patent Document 5 discloses obtaining the number of frames.

JP 2002-057887 A JP 2004-214828 A JP 2006-109205 A JP 2010-205252 A JP 2008-84348 A

However, when it is desired to reduce the total data size of the electronic comic data to the target value, the balance between the image size (vertical and horizontal size) of each page image constituting the electronic comic data and the total data size (total data size) of the electronic comic data. Therefore, it was necessary to determine the compression rate through trial and error.

In recent years, electronic comic data including precisely drawn images has been provided, and even if the compression rate is increased, it is required to make the appearance of the compressed image not noticeably deteriorated.

Patent Documents 1 to 4 disclose image file data compression technology, but when compressing an electronic comic image in units of pages, it is efficient without impairing the appearance of the compressed electronic comic image. There is no disclosure about how to compress well.

As described in Patent Document 1, in a configuration in which compression of an image file is simply repeated until the data size of the image data reaches a target value, when the compression rate is increased, there is a possibility that deterioration in image quality becomes conspicuous. For example, in a page with a large number of frames, a fine image may be drawn, but the degradation of the image quality may be conspicuous. In addition, for example, in a page with a large balloon area, the degradation of text (text) in the balloon may be conspicuous.

Patent Document 5 only describes that the number of frames is acquired, and there is no disclosure or suggestion about data compression based on the number of frames.

As described above, there are comic-specific patterns such as frames and balloons in the images of electronic comic data. However, in Patent Documents 1 to 5 described above, a high compression rate is obtained by using these comic-specific patterns. There is no idea of achieving both high quality and high image quality, and there is no suggestion.

The present invention has been made in view of such circumstances, and when performing data compression of electronic comic data, an electronic comic data compression apparatus, method, and method that can generate electronic comic data with better image quality even at a high compression rate. The purpose is to provide a program.

To achieve the above object, the present invention provides data acquisition means for acquiring electronic comic data including page images of a plurality of pages of comics, the number of frames for each page of page images of a plurality of pages of electronic comic data, and balloons. Information acquisition means for acquiring at least one of the areas of the data, data compression means for compressing the page image of the electronic comic data in units of pages, and data for calculating the total data size of the electronic comic data compressed by the data compression means When the total data size calculated by the size calculating means and the data size calculating means is larger than the target value, at least one of the number of frames per page and the blowing area among the page images of the plurality of pages of the electronic comic data. The page image selected on the basis of the compression ratio is increased and recompressed by the data compression means. A compression control unit that provides an electronic comic data compression apparatus having a.

Here, the “target value” of the total data size is a specified data value. For the “target value”, a designation input from the user may be accepted by the operation means, or a designation input may be accepted by means other than the operation means. For example, the designation input of “target value” may be accepted via a network, or the designation input may be accepted by extracting “target value” added to the electronic comic data from the electronic comic data. The designation input of “target value” may be received in other modes.

With this configuration, when the total data size of the electronic comic data compressed by the data compression means is larger than the target value, the compression rate of the page image selected based on at least one of the number of frames per page and the blowing area is set. Since the compression is further increased, electronic comic data with better image quality can be generated even at a high compression rate.

In one embodiment, when the total data size calculated by the data size calculation unit is larger than the target value, the compression control unit increases the compression rate of the page image as the number of frames decreases, and the data compression unit Perform compression.

In one embodiment, when the total data size calculated by the data size calculation unit is smaller than the target value, the compression control unit lowers the page image compression rate as the number of frames increases, and the data compression unit Perform compression.

In one embodiment, when the total data size calculated by the data size calculation unit is larger than the target value, the compression control unit increases the compression rate of the page image as the area of the balloon is smaller, and the data compression unit Perform compression.

In one embodiment, when the total data size calculated by the data size calculating unit is smaller than the target value, the compression control unit lowers the page image compression rate as the area of the balloon increases, and the data compression unit re-executes the compression. Perform compression.

In one embodiment, there is provided resizing means for changing the vertical and horizontal sizes of each of the page images of the plurality of pages of the electronic comic data to a specified vertical and horizontal size, and the compression control means has a plurality of pages whose vertical and horizontal sizes have been changed by the resizing means. Compress the image.

In one embodiment, there is provided means for selecting, based on electronic comic data, whether to change the compression rate of the page image based on the number of frames or to change the compression rate of the page image based on the area of the balloon.

In one embodiment, there is provided means for receiving an input of a selection instruction for changing the compression rate of the page image based on the number of frames or changing the compression rate of the page image based on the area of the balloon.

Further, the present invention provides at least one of data acquisition means for acquiring electronic comic data including page images of a plurality of pages of comics, and the number of frames for each page of the page images of the plurality of pages of electronic comic data and the area of the balloon. Calculating the total data size of the electronic comic data after being compressed by the data compression means, using the information acquisition means for acquiring the data and the data compression means capable of compressing the page image of the electronic comic data in units of pages, and calculating When the total data size is larger than the target value, the compression ratio of the page image selected based on at least one of the number of frames per page and the blowing area among the plurality of page images of the electronic comic data is increased. And compressing the data by the data compression means, and an electronic comic data compression method comprising: Subjected to.

Further, the present invention provides a data acquisition unit in which the information processing apparatus acquires electronic comic data including page images of a plurality of pages of comics, and the number of frames and the number of balloons for each page of the page images of the plurality of pages of electronic comic data. The total data size of the electronic comic data compressed by the data compression means is calculated using an information acquisition means for acquiring at least one of the areas and a data compression means capable of compressing the page image of the electronic comic data in units of pages. And when the calculated total data size is larger than the target value, the page image selected based on at least one of the number of frames per page and the blowout area among the plurality of page images of the electronic comic data And increasing the compression rate of the data compression means to compress the data compression means. To provide the ram.

The above program can be provided by being recorded on various recording media.

According to the present invention, when data compression of electronic comic data is performed, it is possible to generate electronic comic data with better image quality even at a high compression rate.

Overall configuration diagram showing an example of an electronic comic data distribution system Explanatory drawing showing an example of the file structure of electronic comic data The block diagram which shows the structural example of an electronic comic data compression apparatus The flowchart which shows the flow of the data compression process of 1st Example. Explanatory drawing used for explanation of an example of electronic comic data and page image Explanatory drawing used to explain data compression at the initial compression rate for each page image Explanatory drawing used to explain the change in compression ratio for the page image with the largest number of frames The flowchart which shows the flow of the data compression process of 2nd Example. The flowchart which shows the flow of the data compression process of 3rd Example.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

<Electronic comic data distribution system>
FIG. 1 is an overall configuration diagram illustrating an example of an electronic comic data distribution system. The scanner 1 reads a comic (manga) manuscript on paper to generate an image file including an image for each page of the comic (hereinafter referred to as “page image”). Although FIG. 1 shows an example in which an image file is acquired by reading a comic book on a paper surface as a scanned original by the scanner 1, the present invention is not limited to this case. An image file may be acquired by inputting an electronically generated comic document (digital document) via a network or a recording medium.

The electronic comic editing device 2 is a device that edits electronic comic data including an image file input by the scanner 1 or the like to generate master electronic comic data (hereinafter referred to as “master data”). The electronic comic editing device 2 is configured by a computer device, for example.

The server device 3 converts the master data of the electronic comic data edited by the electronic comic editing device 2 into electronic comic data of a format corresponding to each of the viewer devices 4 (4a to 4d) as necessary, and the electronic data The comic data is transmitted to the viewer device 4 via the network in response to a distribution request from the viewer device 4. The server device 3 is configured by a computer device, for example.

The viewer device 4 receives the electronic comic data transmitted from the server device 3 and displays a page image (or frame image). The viewer device 4 is various mobile terminals such as a mobile phone, a smartphone, and a tablet terminal, or various terminal devices (computer devices) such as a personal computer.

The display screen size of the viewer device 4 varies depending on the model. When the display screen size of the viewer device 4 is smaller than the entire display size of the page image for each page of the electronic comic data, the display corresponding to the display screen size of the viewer device 4 in the page image for each page. Display while moving the range sequentially. Such sequential display on the display screen of the viewer device 4 while moving the display range corresponding to the display screen size in the page image is sometimes referred to as “sequential playback” or “screen feed playback”.

The “electronic comic data” transmitted from the server device 3 to the viewer device 4 is composed of an image file including a page image and an information file (accompanying information).

The page image is composed of an image for each page of a high-resolution image (for example, 3000 × 5000 pixels or 1500 × 2000 pixels).

The information file is information corresponding to all pages (or each page) of the comic. For example, it is described in a markup language such as an XML file.

Fig. 2 shows an example of an information file.

The information file of this example includes page information that is information about the page, frame information that is information about the frame, balloon information that is information about balloons, text area information that is information about text areas, and region of interest information that is information about areas of interest. , Association information indicating the association between these pieces of information, and the like.

Page information includes information about the page, page name, and page ID. The information about the page is information including whether the content image is one page or two spread pages, and information including the size of the original content. The page information in this example includes information about the electronic comic (title ID, title name, author, publisher (copyright owner), year of publication, language, etc.). Further, the page information may include a specified vertical and horizontal size (image size) of the page image related to the image resizing of the page image. Further, the page information may include a designated total data size (target value of the total data size) related to page image data compression.

Frame information includes frame area information. The frame area information is information indicating the area (frame area) of each frame in the page image. The frame area information in this example includes the coordinates of the vertices of each frame and the shape of each frame. The frame area information may be vector data indicating a frame boundary or mask data indicating a frame area. The frame information includes frame order information indicating the playback order of the frames in the page image. The playback order of frames is, for example, information on right / left-open pages, information on contents indicating the language used, frame division detected from frame area information, etc., from upper right to lower left, upper left to lower right, An appropriate pattern is selected from several frame order transition patterns such as the moving direction (left-right direction or up-down direction), and is automatically determined according to the selected transition pattern.

Also, the frame information in this example includes the number of frames per page (the number of frames in one page).

The balloon information includes balloon area information. Examples of the blowout area information include vector data indicating the outer periphery of the blowout area and mask data (bitmap information) indicating the blowout area. The balloon area information is information indicating a balloon area within a page image (or within a frame). The blowout area information may include the shape of the blowout, the position and orientation of the blowout start point (pitch of the blowout), and the size of the blowout. Moreover, you may represent blowing area | region information with the specific position (center position) of blowing, and the size of blowing. The balloon information may further include text information included in the balloon, balloon drawing line attributes (dotted line, solid line, etc.), balloon identification information, and frames to which the balloon belongs.

In addition, the balloon information of this example includes a balloon area per page (total area of balloons within one page).

The text information includes text area information and information related to the text content. As text area information, for example, coordinate data of a plurality of points corresponding to the text area on the drawn line (coordinate data indicating each vertex of the outer periphery of the polygon), vector data indicating the outer periphery of the text area, text area (range) ) Mask data (for example, bitmap information). The information on the contents of the text includes text (text) character attribute information specified by OCR, the number of lines, line spacing, character spacing, display switching method, language used, vertical writing / horizontal writing, reading direction distinction, and the like. . The character attribute information includes a character size (number of points, etc.) and a character type (font, emphasized character, etc.). The text information includes the speech of the speaker in the callout. In addition, translated texts in various languages corresponding to the lines of the original text arranged in the balloon and the language used (translated sentences in two or more languages) may be included in this text information.

The region-of-interest information includes coordinate data indicating each vertex (each vertex of the outer periphery of the polygon) of the region of interest (hereinafter also referred to as “ROI”), vector data indicating the outer periphery of the ROI, and mask data indicating the ROI (for example, Bit map data). The region-of-interest information may include data indicating the shape of the ROI. Further, the region-of-interest information may further include information on a character included in the ROI (for example, a character ID automatically assigned). The region-of-interest information may include priority, importance in display, character identification information (such as name), and character attributes (such as gender and age). The region-of-interest information in this example indicates a region where a character appearing in a comic is drawn.

The association information is information indicating association between area information in the page image. In other words, the association between different types of areas is shown. The association information includes associating text region information and region-of-interest information, association between balloon region information and region-of-interest information, association between text region information and balloon region information, association between text region information and frame information, balloon region Examples include association between information and frame information, association between region-of-interest information and frame information, and the like.

In the following, image resizing (“vertical / horizontal size”) performed mainly when converting the electronic comic data (master data) of the master into electronic comic data (distributed data) of a format corresponding to each of the viewer devices 4 (4a to 4d). (Also referred to as “change”) and data compression (also referred to as “encoding”) will be described.

<Electronic comic data compression device>
In the electronic comic data distribution system of FIG. 1, data compression of electronic comic data is performed by the server device 3, but may be performed by the electronic comic editing device 2.

Hereinafter, the electronic comic data compression apparatus according to the present invention will be specifically described as being applied to the server apparatus 3 or the electronic comic editing apparatus 2.

FIG. 3 is a block diagram showing an internal configuration example of the electronic comic data compression apparatus 10.

The electronic comic data compression apparatus 10 of this example includes a data acquisition means 12, a storage means 14, a display means 16, an operation means 18, and a CPU (central processing unit) 20.

The data acquisition unit 12 acquires electronic comic data including page images of a plurality of comic pages. The data acquisition unit 12 is configured by a network interface that acquires electronic comic data via a network, for example. The present invention is not limited to the case where electronic comic data is acquired via a network. For example, the electronic comic data may be acquired from the storage unit 14 described later or may be acquired from a removable recording medium.

The storage means 14 is constituted by a disk, a memory, or the like. The memory includes RAM, ROM, and flash memory (nonvolatile memory).

The display means 16 is composed of various display devices such as a liquid crystal display device.

The operation means 18 is constituted by various operation devices such as a touch sensor (also referred to as “touch panel”).

The CPU 20 includes resizing means 120, data compression means 122, data size calculation means 124, data size determination means 126, compression order determination means 128 (information acquisition means), and compression control means 130.

The resizing means 120 changes the image size (vertical / horizontal size) of each page image of the electronic comic data to a specified image size (vertical / horizontal size).

The data compression means 122 compresses (encodes) page images of a plurality of pages of electronic comic data in units of pages.

The data size calculation means 124 calculates the total data size (file capacity) of the electronic comic data.

The data size determination unit 126 compares the total data size calculated by the data size calculation unit 124 with the total data size designated in advance (target value of the total data size).

The compression order determination unit 128 (information acquisition unit) acquires at least one of the number of frames for each page of the page image of the plurality of pages of the electronic comic data and the area of the balloon, and the number of frames and the balloon for each acquired page. Based on at least one of these areas, it is determined which page image of a plurality of page images is to be preferentially compressed (compression order).

The compression control unit 130 converts the page images of the plurality of pages of the electronic comic data into page units so that the total data size of the plurality of page images calculated by the data size calculation unit 124 is equal to or less than a target value (specified total data size). The data compression means 122 compresses the data. When the total data size calculated by the data size calculation unit 124 is larger than the target value, the compression control unit 130 of this example increases the compression rate for pages with a higher compression order determined by the compression order determination unit 128. Compress the page image.

<Data compression processing of the first embodiment>
Data compression processing (electronic comic data compression method) of the first embodiment will be described with reference to FIGS. This process is executed by the CPU 20 of the electronic comic data compression apparatus 10 according to a program.

First, the original electronic comic data (image resize and data compression are unprocessed electronic comic data) is acquired by the data acquisition means 12 (step S2). The original electronic comic data 8 shown as an example in FIG. 5 includes page images P1, P2, and P3 for each page.

Next, frame information (including the number of frames per page) regarding the frames in the page images P1, P2, and P3 of the acquired electronic comic data 8 by the compression order determination unit 128 (information acquisition unit) is converted into an electronic comic. Obtained by extracting from the information file of data 8 (step S4). For example, in the case of the electronic comic data of FIG. 5, the page image P1 of the first page has one frame, the page image P2 of the second page has five frames, and the page image P3 of the third page has six frames.

Next, a conversion condition (hereinafter also referred to as “conversion specification”) of electronic comic data corresponding to the viewer device 4 (client terminal) assumed to be distributed is acquired (step S6).

For example, the following conversion conditions (conversion specifications) are specified.
・ Image size of page image: Horizontal size: 960 pixels, Vertical size: 1600 pixels
・ Compression format: JPEG
-Total data size of electronic comic data (total file capacity) ... 750 Kbytes It is assumed that the system user can specify an arbitrary value for this conversion condition. In this example, the designation is input by the operation unit 18 and the storage unit 14 stores the designation. If the conversion condition is specified in the information file of the electronic comic data, the conversion condition may be extracted from the electronic comic data.

Next, the number of frames of the electronic comic data 8 is determined for each page of the page images P1, P2, and P3 by the compression order determination means 128 (step S8).

Next, the image size (vertical / horizontal size) of the page image is changed (image resizing) by the resizing means 120 (step S10).

Next, the data compression means 122 compresses the page images P1, P2, and P3 of the electronic comic data 8 in units of pages (step S12).

The Q value (a parameter for determining the image quality after compression) at the time of data compression (encoding) at this stage is a set value (initial value) set in the storage unit 14 in advance. For example, when the compression format is JPEG, the Q value is set to “60”.

Note that the data compression format (form) is not limited to JPEG, and may be compressed in another format.

Next, the total data size (file capacity) of the electronic comic data is calculated by the data size calculation means 124 (step S14). In this example, the total (total data size) of the data sizes of all page images included in the electronic comic data is calculated.

Next, the data size determination means 126 compares the total data size after data compression with the specified total data size (target value) acquired in step S6, and the total data size after data compression is the specified total data size. It is determined whether it is larger than the data size (step S16).

For example, as shown in FIG. 6, after data compression, the data size is 243 Kbytes for the page image P1 of the first page, 256 Kbytes for the page image P2 of the second page, and 300 Kbytes for the page image P3 of the third page. Therefore, the total data size (file capacity) is 799 Kbytes (= 243 + 256 + 300 Kbytes). That is, since the designated total data size (target value) is 750 Kbytes, it exceeds 49 Kbytes (= 799-750 Kbytes) (Yes in step S16).

Therefore, the compression rate is increased (that is, the Q value is lowered), and data compression is performed again (step S18). Here, the compression rate is increased preferentially from page images with a small number of frames. In this example, the compression rate is increased from the previous time, and data compression is performed again on the page image of the original electronic comic data.

In the electronic comic data 8 shown in FIG. 5, the page image P1 of the first page is one frame, the page image P2 of the second page is five frames, and the page image P3 of the third page is six frames. Data compression is performed again by increasing the compression rate for the page image P1 of the first page (decreasing the Q value). When the Q value is “55”, the data size of the page image P1 of the first page after data compression is 230 Kbytes, and the total data size of the electronic comic data 8 is larger than the target value of 750 Kbytes. Until the total data size after the first data compression becomes 49 Kbytes or more, the compression rate is sequentially increased (Q value is sequentially decreased), and compression encoding is performed. In this embodiment, by setting the Q value to “40”, the page image is converted (encoded) to the target total data size.

For example, as shown in FIG. 7, while maintaining the vertical and horizontal sizes of the page image P1 of the first page at the vertical and horizontal sizes immediately after the resizing (horizontal 960 pixels, vertical 1600 pixels), the Q value for the page image P1 of the first page is Data compression is repeated by decreasing in order from “60” to “55” and from “55” to “40”. The decrement value of the Q value can take any value such as -5, -4, -3, -2, or -1.

For easy understanding of the technology, the case where the compression control means 130 sequentially increases the compression ratio of only P1 having the smallest number of frames (that is, the compression ratio of P1> the compression ratio of P2 = the compression ratio of P3) has been described. However, the present invention is not limited to such a case.

In the present specification, in the compression order determination of the compression order determination unit 128 and the compression control of the compression control unit 130, “the smaller the number of frames, the higher the compression rate of the page image” is. Embodiments are included. As a first mode, there is a mode in which the compression rate is increased stepwise as the number of frames is smaller for each page image. In this aspect, in the case of the page images P1 to P3 in FIG. 6, since the number of frames of P1 <the number of frames of P2 <the number of frames of P3, the compression ratio of P1> the compression ratio of P2> the compression ratio of P3. In this aspect, when the total data size is larger than the target value, the number of images to be compressed at a time increases, but it is possible to achieve an image quality that does not feel uncomfortable between pages. As a second mode, there is a mode in which the number of frames for each page image is compared with a threshold value, and the compression rate is increased only for page images having a smaller number of frames than the threshold value. In this aspect, it is possible to eliminate the deterioration in the quality of the page image in which the number of frames is equal to or greater than the threshold value. As described above, the compression rate may be increased only for the page image having the smallest number of frames.

Comic page images with a small number of frames tend to have high image redundancy, and even if the compression rate is increased (lowering the Q value), the image quality of the page image is hardly noticeable. Therefore, when performing image conversion that stores electronic comic data in a target total data size (total file capacity), according to the present invention, it is possible to automatically generate electronic comic data consisting only of a good-looking page image.

<Data Compression Processing of Second Embodiment>
The data compression processing (electronic comic data compression method) of the second embodiment will be described with reference to FIG. This process is executed by the CPU 20 of the electronic comic data compression apparatus 10 according to a program.

The compression control means 130 of the second embodiment causes the data compression means 122 to compress each of a plurality of page images of electronic comic data at a preset initial compression rate, and the total data size after compression is a target value. If the number of frames is smaller, the more the number of frames, the lower the page image compression rate, and the data compression means 122 performs recompression.

In FIG. 8, the same steps as those in the data compression process of the first embodiment shown in FIG. Hereinafter, only differences from the first embodiment will be described.

If it is determined in step S16 that the total data size after data compression (step S12) is larger than the specified total data size, a page image with a smaller number of frames than in the previous example is displayed as in the first embodiment. Compression is performed at a high compression rate (step S18), the total data size is calculated (step S20), and it is determined again whether it is larger than the specified total data size (target value) (step S22). If it is larger than the data size, steps S18 to S20 are repeated, and if it is less than the designated total data size, this processing is terminated.

If it is determined in step S16 that the total data size after data compression (step S12) is less than or equal to the specified total data size, the following processing is executed in the second embodiment.

In step S24, it is determined whether or not the total data size after data compression (step S12) is smaller than the specified total data size. If it is smaller than the designated total data (Yes in step S24), the page image with a large number of frames is compressed at a lower compression rate than the previous time (step S26), and the total data size of the electronic comic data is calculated (step S28). ) If the total data size (target value) is still smaller than the designated total data size, steps S26 to S28 are repeated. If the total data size is larger than the designated total data size, the previous (previous) compression result (compressed page image) is finalized. It is adopted as a page image of typical electronic comic data (step S30).

In the present specification, in the compression order determination of the compression order determination unit 128 and the compression control of the compression control unit 130, “the more the number of frames, the lower the page image compression rate”, the following first mode and A second aspect is included. As a first mode, there is a mode in which the compression rate is gradually decreased for a page image having a larger number of frames according to the number of frames for each page image. In this aspect, in the case of the page images P1 to P3 in FIG. 6, since the number of frames of P1 <the number of frames of P2 <the number of frames of P3, the compression ratio of P1> the compression ratio of P2> the compression ratio of P3. In this aspect, when the total data size is smaller than the target value, the number of images to be compressed at a time increases, but it is possible to achieve an image quality that does not feel uncomfortable between pages. As a second mode, there is a mode in which the number of frames for each page image is compared with a threshold value, and the compression rate is reduced only for the page image having a larger number of frames than the threshold value. Only the page image with the largest number of frames may have a low compression rate.

Electronic comic data with a large number of frames generally tends to have low redundancy, and image quality deterioration tends to be noticeable during compression (encoding). Therefore, according to the present embodiment, when there is a margin in capacity, deterioration in image quality is not conspicuous by reducing the compression rate from the initial set value (increasing the Q value) and performing recompression. It can be electronic comic data. That is, when data compression is performed so that the electronic comic data is stored in a predetermined total data size (file capacity), it is possible to create distribution data having good appearance by this method.

<Data Compression Processing of Third Embodiment>
In the first and second embodiments, the data compression is performed by adjusting the compression rate based on the number of frames of the page image. In the third embodiment, the compression is performed based on the area of the page image. Adjust the rate.

The data compression process (electronic comic data compression method) of the third embodiment will be described with reference to FIG. This process is executed by the CPU 20 of the electronic comic data compression apparatus 10 according to a program.

First, the original electronic comic data is acquired by the data acquisition means 12 (step S52).

Next, by using the compression order determination means 128 (information acquisition means), the blowing information (including the balloon area in units of pages) regarding the blowing in the page images P1, P2, and P3 of the acquired electronic comic data 8 is obtained as electronic comic data. 8 is obtained by extracting from the information file 8 (step S54).

Next, the conversion condition (conversion specification) of the electronic comic data corresponding to the viewer device 4 (client terminal) assumed to be distributed is acquired (step S56).

Next, the compression order determination means 128 determines the area of the electronic comic data 8 that is blown out in units of pages of the page images P1, P2, and P3 (step S58).

Next, the image size (vertical / horizontal size) of the page image is changed by the resizing means 120 (step S60).

Next, the data compression means 122 compresses the page images P1, P2, and P3 of the electronic comic data 8 in units of pages (step S62).

Next, the total data size (file capacity) of the electronic comic data is calculated by the data size calculation means 124 (step S64).

Next, the data size determination unit 126 compares the total data size after data compression with the specified total data size (target value) acquired in step S56, and the total data size after data compression is It is determined whether it is larger than the total data size (step S66).

If it is larger than the designated total data size (Yes in step S66), the compression rate is increased (that is, the Q value is lowered), and data compression is performed again (step S68). Here, the compression rate is preferentially increased from the page image with a small area of the balloon. In this example, recompression is performed on the page image of the original electronic comic data at a high compression rate. The total data size is calculated (step S70), and it is determined again whether or not it is larger than the designated total data size (step S72). If it is still larger than the designated total data size, steps S68 to S70 are repeated and designated. If the total data size is equal to or smaller than the total data size, the process is terminated.

If it is determined in step S66 that the total data size after data compression (step S62) is less than or equal to the specified total data size, the following processing is executed in the second embodiment.

In step S74, it is determined whether the total data size after data compression (step S62) is smaller than the designated total data size (step S74). If it is smaller than the specified total data (Yes in step S74), the page image having a large balloon area is compressed at a lower compression rate than the previous time (step S76), and the total data size of the electronic comic data is calculated (step S78). If the total data size is still smaller than the designated total data size, steps S76 to S78 are repeated. If the total data size is larger than the designated total data size, the previous (previous) compression result is adopted as the final electronic comic data (step S80). ).

In general, comic images with a small balloon area have few lines (characters) and are often in a state where the lines can be read (viewed) even if the compression rate is increased (decreasing the Q value).

In the present specification, in the compression order determination of the compression order determination unit 128 and the compression control of the compression control unit 130, “the smaller the area of the balloon, the higher the compression ratio of the page image” is. A second aspect is included. As a first mode, there is a mode in which the compression ratio is increased stepwise as the page image has a smaller balloon area, depending on the size of the balloon area for each page image. For example, in the page images P1 to P3 in FIG. 6, if P1 blowing area <P2 blowing area <P3 blowing area, P1 compression ratio> P2 compression ratio> P3 compression ratio. In this aspect, when the total data size is larger than the target value, the number of images to be compressed at a time increases, but it is possible to achieve an image quality that does not feel uncomfortable between pages. As a second mode, there is a mode in which the area of the balloon is compared with a threshold value for each page image, and the compression rate is increased only for the page image whose area of the balloon is smaller than the threshold value. In this aspect, it is possible to eliminate the deterioration in the quality of the page image in which the area of the balloon is equal to or greater than the threshold value. The compression rate may be increased only for the page image having the smallest balloon area.

Further, in this specification, in the compression order determination of the compression order determination unit 128 and the compression control of the compression control unit 130, “the larger the area of the balloon, the lower the page image compression rate” A second aspect is included. As a first mode, there is a mode in which the compression rate is gradually decreased for a page image having a larger balloon area in accordance with the size of the balloon area for each page image. For example, in the page images P1 to P3 in FIG. 6, if P1 blowing area <P2 blowing area <P3 blowing area, P1 compression ratio> P2 compression ratio> P3 compression ratio. As a second mode, there is a mode in which the area of the balloon is compared with a threshold value for each page image, and only the page image having the balloon area larger than the threshold value has a low compression rate. The compression rate may be lowered only for the page image having the largest balloon area.

<Mode selection>
It is preferable that the frame number determination mode for determining the compression order of the page image based on the number of frames and the blowing determination mode for determining the compression order of the page image based on the area of the balloon are selectable.

For example, the CPU 20 automatically selects the frame number determination mode or the balloon determination mode based on the frame information and the balloon information in the information file of the electronic comic data. For example, when the number of frames is only a page larger than a threshold value (frame number threshold value), or when the ratio of pages whose frame number is larger than the threshold value (frame number threshold value) is higher than the threshold value (ratio threshold value), A mode of selecting the determination mode is conceivable. Further, when only pages whose blowing area is larger than the threshold (blowing area threshold), or when the ratio of pages whose blowing area is larger than the threshold (blowing area threshold) is higher than the threshold (ratio threshold), A mode of selecting the number determination mode is conceivable.

Further, it is preferable that the operation means 18 accepts a selection instruction input for selecting the frame number determination mode or the blowout determination mode. For example, if you want to prioritize the image quality of a page image with a large number of frames, select the frame number determination mode, and if you want to prioritize the ability to read words reliably, select the blowout determination mode. Is preferred.

The present invention is not limited to the examples described in the present specification and the examples illustrated in the drawings, and various design changes and improvements may be made without departing from the scope of the present invention. is there.

10: Electronic comic data compression device, 12: Data acquisition means, 14: Storage means, 16: Display means, 18: Operation means, 20: CPU, 120: Resize means, 122; Data compression means, 124: Data size calculation means 126: data size determination means, 128: compression order determination means (information acquisition means), 130: compression control means

Claims

Data acquisition means for acquiring electronic comic data including page images of a plurality of comic pages;
Information acquisition means for acquiring at least one of the number of frames per page and the area of the balloon in the page image of the plurality of pages of the electronic comic data;
Data compression means capable of compressing the page image of the electronic comic data in units of pages;
Data size calculating means for calculating the total data size of the electronic comic data after being compressed by the data compressing means;
When the total data size calculated by the data size calculating means is larger than a target value, at least one of the number of frames per page and the blowing area among the plurality of page images of the electronic comic data. Compression control means for increasing the compression rate of the page image selected based on the data compression means and recompressing the data;
Electronic comic data compression device equipped with.
When the total data size calculated by the data size calculation unit is larger than a target value, the compression control unit increases the compression rate of the page image as the number of frames decreases, and the data compression unit The electronic comic data compression apparatus according to claim 1, wherein recompression is performed.
When the total data size calculated by the data size calculation unit is smaller than a target value, the compression control unit reduces the compression rate of the page image as the number of frames increases, and the data compression unit The electronic comic data compression apparatus according to claim 2, wherein recompression is performed.
When the total data size calculated by the data size calculation unit is larger than a target value, the compression control unit increases the compression rate of the page image as the area of the blowout decreases, and the data compression unit The electronic comic data compression apparatus according to claim 1, wherein recompression is performed.
When the total data size calculated by the data size calculation unit is smaller than a target value, the compression control unit lowers the compression rate of the page image as the area of the balloon increases, and the data compression unit The electronic comic data compression apparatus according to claim 4, wherein recompression is performed.
Resize means for changing the vertical and horizontal size of each of the page images of the plurality of pages of the electronic comic data to a specified vertical and horizontal size;
6. The electronic comic data compression device according to claim 1, wherein the compression control unit compresses the page images of the plurality of pages whose vertical and horizontal sizes have been changed by the resizing unit.
A means for selecting, based on the electronic comic data, whether to change the compression ratio of the page image based on the number of frames or to change the compression ratio of the page image based on the area of the balloon. The electronic comic data compression device according to any one of 1 to 6.
7. The apparatus according to claim 1, further comprising means for receiving an input of a selection instruction to change the compression ratio of the page image based on the number of frames or to change the compression ratio of the page image based on the area of the balloon. The electronic comic data compression apparatus of any one of them.
Information processing device
Data acquisition means for acquiring electronic comic data including page images of a plurality of pages of comics, and information for acquiring at least one of the number of frames per page and the area of balloons in the page images of the plurality of pages of the electronic comic data Using an acquisition unit and a data compression unit capable of compressing the page image of the electronic comic data in units of pages,
Calculating a total data size of the electronic comic data after being compressed by the data compression means;
When the calculated total data size is larger than a target value, a page image selected based on at least one of the number of frames per page and the blowing area among the plurality of page images of the electronic comic data Increasing the compression rate of the data compression means to the data compression means;
Electronic comic data compression method for executing.
Information processing device
Data acquisition means for acquiring electronic comic data including page images of a plurality of pages of comics, and information for acquiring at least one of the number of frames per page and the area of the balloon in the page images of the plurality of pages of the electronic comic data Using acquisition means, and data compression means capable of compressing the page image of the electronic comic data in units of pages,
Calculating a total data size of the electronic comic data after being compressed by the data compression means;
When the calculated total data size is larger than a target value, a page image selected based on at least one of the number of frames and the blowing area for each page among the plurality of page images of the electronic comic data Increasing the compression ratio of the data compression means to the data compression means;
A program for running.