JP2008090377A - Rasterizing device, program and method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a technique efficiently creating bit-map data for each band from print data including an image object to be downloaded. <P>SOLUTION: A printer 50 performs the following processes with respect to a band in which an image object is included: (1) if the image object has not been downloaded yet, the image object is downloaded; (2) the image object is rasterized; (3) if the image object is not included in another band that is rasterized after the band, the image object is deleted from memory when rasterized; if the image object is included in a band that is rasterized after the band, the image object is not deleted even if rasterized. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a technique for creating bitmap data by rasterizing data.

The matters which become the background of the present invention are listed below.
(1) For example, the printer is used by being connected to an external device (PC, digital camera, portable media, etc.). Some printers, when receiving print data output from an external device, rasterize the print data to create bitmap data. The printer prints on the print medium based on the created bitmap data.
(2) The print data may include an object (referred to as a DL object in this specification) that needs to be downloaded from the communication network. For example, an image object in JPEG format can be a DL object. The print data includes an address on the communication network where the DL object is stored. The printer accesses an address included in the print data, and downloads a DL object from the address. The printer rasterizes the downloaded DL object and creates bitmap data. For example, Patent Document 1 below discloses a printer that downloads and rasterizes a DL object.
(3) Some printers divide print data into a plurality of areas (bands) and sequentially create bitmap data for each area. That is, there is a printer that creates bitmap data in order in band units. For example, Patent Document 2 below discloses this type of printer.

Japanese Patent Laid-Open No. 2002-91726 JP-A-2002-96506

The above-mentioned patent document 1 discloses downloading and rasterizing a DL object, but does not disclose creating bitmap data in band units. In addition, the above Patent Document 2 discloses that bitmap data is created in band units, but does not disclose downloading and rasterizing a DL object.
Patent Literature 1 and Patent Literature 2 are useful techniques that are established independently. However, these documents do not disclose creation of bitmap data in band units from data including DL objects. When bitmap data is created in band units from data including a DL object, a methodology for efficiently executing the process is not known.

  The present invention provides a technique capable of efficiently creating bitmap data in band units from data including a DL object.

  The rasterizing apparatus of the present invention will be described with reference to FIG. FIG. 1 simply shows data to be rasterized. The data in FIG. 1 is merely an example. The technical scope of the present invention is not construed as being limited by the contents of FIG. 1 and the following description relating thereto. The technical scope of the present invention is objectively determined by the matters described in the claims.

The rasterizing apparatus of the present invention is used by being connected to a communication network. The rasterizer can rasterize data including DL objects that need to be downloaded from its communication network. In the example of FIG. 1, the data 10 including the DL object 20 is rasterized.
The rasterization apparatus of the present invention includes a first storage area that can store a downloaded DL object, and a rasterizer that rasterizes data and sequentially creates bitmap data in band units.
In the example of FIG. 1, the data 10 to be rasterized is divided into a plurality of bands 30 to 38. The rasterizer creates bitmap data of each band 30 to 38 in order. That is, the bitmap data of the band 30 is created, and then the bitmap data of the band 32 is created. Similarly, bitmap data is created in the order of bands 34, 36, and 38.

The rasterizer executes the following processing for a band including a predetermined DL object.
(1) If the predetermined DL object is not stored in the first storage area, the predetermined DL object is downloaded and stored in the first storage area. When the predetermined DL object is stored in the first storage area, the predetermined DL object is not downloaded.
(2) Rasterize the predetermined DL object stored in the first storage area.
(3) When the predetermined DL object is not included in a band in which bitmap data is created after the band, the bitmap data of the predetermined DL object is created for the band from the first storage area. If the predetermined DL object is erased and the predetermined DL object is included in a band in which bitmap data is generated after the band, the bitmap data of the predetermined DL object is generated for the band. The predetermined DL object is not erased from the first storage area.

In the example of FIG. 1, the DL object 20 is disposed across a band 32 and a band 34 to be rasterized next to the band 32. In this case, even if the bitmap data of the DL object 20 is created for the band 32, the DL object 20 is not erased from the first storage area. When creating the bitmap data of the band 34, it is not necessary to download the DL object 20 again. The same DL object is prevented from being downloaded multiple times. This rasterizing apparatus can efficiently create bitmap data.
If the DL object 20 is included only in the band 32 (when it is not included after the band 34), when the bitmap data of the DL object 20 is created for the band 32, the first storage area The DL object 20 is deleted. Occurrence of an event that unnecessary data continues to be stored for a long time is suppressed. This rasterizing apparatus can efficiently use the memory (first storage area).
The rasterizing apparatus of the present invention can efficiently create bitmap data in band units from data including DL objects.

Note that “deleting the predetermined DL object from the first storage area when the bitmap data of the predetermined DL object is created for the band” refers to the bitmap of the predetermined DL object for the band. It does not mean that the DL object is erased as soon as the data is created. The timing at which the DL object is deleted may be any timing until creation of bitmap data for the next band is started.
For example, in the example of FIG. 1, when the bitmap data of the DL object 20 is created for the band 34, the DL object 20 may be deleted before the creation of the bitmap data of the band 36 is started.

Further, the above-mentioned “Do not erase the predetermined DL object from the first storage area” means that the DL object in the downloaded data format (eg, vector format) is not erased and / or the data after rasterization This means that the DL object of the format is not deleted.
For example, when the bitmap data of the band 32 in FIG. 1 is created, the DL object 20 in the downloaded data format is rasterized. The first storage area may continuously store the DL object 20 in the downloaded data format after the bitmap data of the DL object 20 is created for the band 32 (that is, in the downloaded data format). DL objects are not erased). In this case, when the bitmap data of the band 34 is created, the DL object 20 is rasterized again.
On the other hand, the first storage area may continuously store the DL object 20 in the data format after being rasterized after the bitmap data of the DL object 20 is created for the band 32 (that is, rasterized). (The DL object in the data format after is not deleted). In this case, it is not necessary to rasterize the DL object 20 when the bitmap data of the band 34 is created. This is because the DL object 20 in the data format after being rasterized is stored in the first storage area.

The rasterizer may execute the above process (3) as follows.
That is, the rasterizer determines whether or not the predetermined DL object is included in a band in which bitmap data is created next to the band.
If the predetermined DL object is not included in the band in which the bitmap data is created next to the band, the rasterizer stores the first storage area when the bitmap data of the predetermined DL object is created for the band. The predetermined DL object is deleted.
When the predetermined DL object is included in a band in which bitmap data is created next to the band, the rasterizer reads from the first storage area even if bitmap data of the predetermined DL object is created for the band. The predetermined DL object is not deleted.

On the other hand, the rasterizer may execute the above process (3) as follows.
That is, the rasterizer determines whether or not the predetermined DL object is included in any band in which bitmap data is created after the band.
If the predetermined DL object is not included in any band for which bitmap data is created after the band, the rasterizer first generates the bitmap data of the predetermined DL object for the band. The predetermined DL object is erased from the storage area.
When the predetermined DL object is included in any band for which bitmap data is created after the band, the rasterizer stores the first memory even if the bitmap data of the predetermined DL object is created for the band. The predetermined DL object is not deleted from the area.

The rasterizing device may further include a device that creates conversion data by converting each object included in the data into a rectangular object positioned by the coordinates of a rectangular vertex including the shape of the object. .
For example, the data 10 in FIG. 1 includes objects 12, 14, 16, and 20. Objects 12, 14, and 16 are not DL objects. The object 20 is a DL object.
The rasterizing device converts each object 12, 14, 16, 20 into a rectangular object. For example, the object 12 is converted into a rectangular object 12a including the shape of the object 12 (“A” in the example of FIG. 1). The rectangular object 12a is positioned by the coordinates (x1, y1) and (x2, y2) of the rectangular vertex.
In the example of FIG. 1, a rectangular object (for example, 12a) is positioned by the coordinates of two vertices on one diagonal of the rectangle. However, the rectangular object may be positioned by the coordinates of the four vertices of the rectangle. The rectangular object may be positioned by the coordinates of one vertex of the rectangle, the length of the long side of the rectangle, and the length of the short side of the rectangle. The rectangular object may be positioned by the coordinates of one vertex of the rectangle and the length of the diagonal line. The rectangular object may be positioned by the coordinates of at least one vertex.
As in the case of the object 12, the objects 14 and 16 are also converted into rectangular objects 14a and 16a. The DL object 20 is also converted into a rectangular object (vertices are (x3, y3) and (x4, y4)). In the example of FIG. 1, since the shape of the DL object 20 itself is a rectangle, the rectangle object is not illustrated.

The rasterizer described above creates bitmap data in order from the created conversion data in band units. Further, the rasterizer specifies the objects included in each band based on the above coordinates. For example, the rasterizer determines whether or not the object 12 is included in the band 30 based on the coordinates (x1, y1) and / or the coordinates (x2, y2). Similarly, the rasterizer determines whether other objects 14, 16, and 20 are included in the band 30 based on the coordinates of the vertices of the rectangular object.
When a rectangular object is not used (for example, when an object is positioned by vector format data), it is not easy to specify an object included in a band. On the other hand, in the present invention, an object is positioned by simple rectangular coordinates. For this reason, the rasterizer can easily identify the object included in the band.

The rasterizing device includes a second storage area capable of storing bitmap data for at least one band and a third storage area capable of storing bitmap data for at least one band. Furthermore, you may provide.
In this case, the rasterizer preferably stores the bitmap data of each band alternately in the second storage area and the third storage area. For example, the first band bitmap data is stored in the second storage area. Bit map data of the second band next to the first band is stored in the third storage area. Bit map data of the third band next to the second band is stored in the second storage area. Thereby, the storage content of the second storage area is updated. Bit map data of the fourth band next to the third band is stored in the third storage area. Thereby, the storage contents of the third storage area are updated.
In this way, the rasterizing process for the next band can be executed while printing the bitmap data for one band, so that the processing time can be shortened.
The “bitmap data for one band” may be a fixed value or a fluctuating value.

A printer must have a smaller memory capacity than a PC or the like. For this reason, the above-described rasterizing apparatus that can efficiently use the memory can be preferably used in a printer. This printer includes the above-described rasterizing device and printing device. This printing apparatus executes the following processing.
(A) When bitmap data of the first band is created by the rasterizing device, printing is performed on a print medium based on the bitmap data of the band.
(B) When bitmap data of the next band is created by the rasterizing device, printing is performed on a print medium based on the bitmap data of the band.
(C) The process of (B) is continued until printing on the print medium based on the bitmap data of the last band.

The following computer programs are also useful. This computer program realizes an apparatus for rasterizing data including DL objects that need to be downloaded from a communication network.
This computer program causes a computer mounted on the above-described rasterizing apparatus to execute a process of rasterizing data and sequentially generating bitmap data in band units. In the rasterization process, the following process is executed for a band including a predetermined DL object.
(1) If the predetermined DL object is not stored in the predetermined storage area, the predetermined DL object is downloaded and stored in the predetermined storage area. When the predetermined DL object is stored in the predetermined storage area, the predetermined DL object is not downloaded.
(2) Rasterize the predetermined DL object stored in the predetermined storage area.
(3) If the predetermined DL object is not included in a band in which bitmap data is created after the band, the predetermined storage area is created when bitmap data of the predetermined DL object is created for the band. The predetermined DL object is deleted. When the predetermined DL object is included in a band in which bitmap data is created after the band, the predetermined storage area stores the predetermined DL object even if bitmap data of the predetermined DL object is created. Do not erase the DL object.
According to the computer program of the present invention, it is possible to realize a rasterizing device capable of efficiently creating bitmap data in band units from data including DL objects.

The technical idea of the present invention can also be expressed as a method. In this method, bitmap data is generated in band units by rasterizing data including DL objects that need to be downloaded from a communication network. In the rasterizing method, the following steps are performed for a band including a predetermined DL object.
(1) If the predetermined DL object is not stored in the predetermined storage area, the predetermined DL object is downloaded and stored in the predetermined storage area. When the predetermined DL object is stored in the predetermined storage area, the predetermined DL object is not downloaded.
(2) Rasterize the predetermined DL object stored in the predetermined storage area.
(3) If the predetermined DL object is not included in a band in which bitmap data is created after the band, the predetermined storage area is created when bitmap data of the predetermined DL object is created for the band. The predetermined DL object is deleted. When the predetermined DL object is included in a band in which bitmap data is created after the band, the bitmap data of the predetermined DL object is created for the band from the predetermined storage area. Do not erase the DL object.
If this method is used, bitmap data can be efficiently created in band units from data including DL objects.

Here, the main features of the techniques described in the following examples are summarized.
(Mode 1) The rasterizing device is built in the printer.
(Mode 2) The printer creates bitmap data in band units from print data. Bitmap data for each band is created in the order of printing on the print medium.
(Mode 3) The printer is connected to a network such as a local area network.
(Mode 4) The DL object included in the print data is an image object.
(Form 5) The image object includes an address (URL) on the Internet where the image data is stored. The printer accesses the address included in the image object and downloads the image data.

(First embodiment)
A first embodiment of the present invention will be described with reference to the drawings. FIG. 2 shows the printer 50 of this embodiment. The printer 50 is used by being connected to the Internet 86.
(Printer configuration)
The printer 50 includes a control device 52, a storage device 54, a display device 66, an operation device 68, a slot unit 70, a printing device 74, and an input / output port 76.
The control device 52 is configured by a CPU or the like. The control device 52 comprehensively controls each process executed by the printer 50. For example, the control device 52 can execute processing for rasterizing print data and creating bitmap data. That is, the control device 52 functions as a rasterizer.
The storage device 54 is configured by a ROM, a RAM, an EEPROM, or the like. The storage device 54 stores a program for the control device 52 to execute each process. Further, the storage device 54 can store various data generated in the course of executing the above program. The storage device 54 has storage areas 56, 58, 60, 62 and 64. The contents of the data stored in the storage areas 56 to 64 will be described next.

The DL object storage area 56 can store DL objects (image data) downloaded from the Internet 86. The DL object will be described later.
The first bitmap data storage area 58 can store bitmap data for at least one band. The band will be described later.
The second bitmap data storage area 60 can also store bitmap data for at least one band.
The processing data storage area 62 can store print data and layout data obtained by converting the print data. The print data and layout data will be described later.
The position data storage area 64 is used in a second embodiment to be described later. The contents of the data stored in the position data storage area 64 will be described later.

The display device 66 is configured by a liquid crystal display or the like. The display device 66 can display various data.
The operating device 68 is composed of a plurality of keys. The user can input various information to the printer 50 by operating the operation device 68.
The slot unit 70 can receive various memory cards 72.
The printing device 74 is an inkjet or laser printing device. The printing device 74 can print on printing paper (not shown).
An Internet line 80 and a LAN line 82 are connected to the input / output port 76. The internet line 80 is connected to the internet 86. The printer 50 can communicate with various devices 94, 96, 98, 100 on the Internet 86. The LAN line 82 is connected to the PC 90. The printer 50 can communicate with the PC 90.

The user can instruct the printer 50 to print the content displayed on the PC 90 by operating the PC 90. In this case, print data is sent from the PC 90 to the printer 50. The printer 50 prints based on the print data sent from the PC 90.
Further, the user can instruct the printer 50 to print the data stored in the memory card 72 by operating the operation device 68. In this case, the printer 50 takes in the print data stored in the memory card 72 and prints based on the print data.

(Processing executed by the printer)
A printing process executed by the printer 50 will be described. This printing process is executed by the control device 52. FIG. 3 shows a flowchart of print processing executed by the printer 50. This print processing is executed when print data is sent from the PC 90 or when an instruction to print the print data stored in the memory card 72 is given. Hereinafter, a case where print data stored in the memory card 72 is printed will be described as an example.
The printer 50 reads the print data stored in the memory card 72 (S10). This print data is stored in the processing data storage area 62 (see FIG. 2). FIG. 4 shows a visual representation of the print data 110 stored in the memory card 72. The print data 110 is XHTML-Print data. In order to print the XHTML-Print data 110, it is necessary to rasterize the data 110 to create bitmap format data.

The print data 110 in FIG. 4 includes three objects 112, 114, and 116. Objects 112 and 114 are JPEG format image objects. The print data 110 does not include image data of the image objects 112 and 114. The image data of each image object 112, 114 is stored in another device on the Internet. The print data 110 includes addresses on the Internet where the image data of the image objects 112 and 114 are stored. The printer 50 downloads the image data of the image objects 112 and 114 from the Internet 86 by accessing the address included in the print data 110. As a result, the printer 50 can create bitmap data of the image objects 112 and 114. Each of the image objects 112 and 114 is an object that needs to be downloaded from the Internet 86, and may be referred to as a “DL object” below. In this embodiment, it is assumed that the image data of each image object 112, 114 is stored in the server 100 shown in FIG.
The object 116 in FIG. 4 is a text object. The printer 50 can create bitmap data from the text object 116 and print characters (Sample) of the text object 116 on printing paper. That is, the text object 116 does not need to be downloaded from the Internet 86.

FIG. 5 shows the data structure of the XHTML-Print data 110 of FIG. The print data 110 in FIG. 5 includes data 132 corresponding to the image object 112, data 134 corresponding to the image object 114, and data 136 corresponding to the text object 116.
Data 132 indicates that the image data is in JPEG format (img1.jpg). The data 132 includes an address on the Internet where image data is stored (not shown in FIG. 5). That is, the data 132 includes the address (URL) of the server 100 (see FIG. 2).
Data 134 indicates that the image data is in SVG format (Scalable Vector Graphics) (img2.svg). The data 134 includes an address on the Internet where the image data is stored (the address of the server 100).
The data 136 includes text data of characters “Sample”.

When the printer 50 finishes S10 of FIG. 3, it executes a layout process (S12). In this layout process, each object 112, 114, 116 included in the XHTML-Print data 110 read in S10 is converted into a rectangular object.
The layout process will be described with reference to FIGS. FIG. 6 shows a visual representation of the data 140 (layout data 140) after the print data 110 of FIG. 4 has been converted by the layout process. FIG. 7 shows the data structure of the layout data 140 of FIG.

The image object 112 in FIG. 4 is converted into a rectangular image object 142 in FIG. The rectangular image object 142 is positioned by two rectangular coordinates C1 and C2 that are substantially circumscribed by the image object 112. Since the image object 112 itself is rectangular, the rectangular image object 142 has the same rectangle as the image object 112.
The coordinates C1 and C2 are two coordinates (hereinafter referred to as diagonal coordinates) located on one diagonal line of the rectangle. The data 154 in FIG. 7 corresponds to the rectangular image object 142 in FIG. “40 80” of the data 154 corresponds to the coordinate C1. “125 120” of the data 154 corresponds to the coordinate C2.

  The image object 114 in FIG. 4 is converted into the rectangular image object 144 in FIG. The rectangular image object 144 is positioned by rectangular diagonal coordinates C3 and C4 that substantially circumscribe the image object 114. Data 156 in FIG. 7 corresponds to the rectangular image object 144 in FIG. “60 130” of the data 156 corresponds to the coordinate C3. “150 190” in the data 156 corresponds to the coordinate C4.

The text object 116 in FIG. 4 is converted into the rectangular text object group 146 in FIG. The text object 116 is a 6-character text “Sample”. In this case, each of the six characters is converted into a rectangular text object 146.
For example, the character “S” is positioned by rectangular diagonal coordinates C5 and C6 that circumscribe the “S”. The data 158 in FIG. 7 corresponds to the rectangular text object 146 of the character “S” in FIG. “50 200” in the data 158 corresponds to the coordinate C5. “55 208” of the data 158 corresponds to the coordinate C6. Further, “serif s 20pt” in the data 158 means that the character “S” is in a 20-point font.
Similarly, each of the other characters “a”, “m”, “p”, “l”, and “e” is converted into a rectangular text object 146. In FIG. 7, only data 158 corresponding to the character “S” and data 160 corresponding to the character “a” are shown. Data corresponding to the other characters “m”, “p”, “l”, and “e” are not shown.
Note that the data 152 in FIG. 7 indicates the dimensions of the printing paper (vertical 210, horizontal 297).

The layout data 140 may include the following data in addition to the data shown in FIG.
(1) One coordinate of the vertex of the rectangular object and the vertical and horizontal lengths of the rectangle (2) One coordinate of the rectangular object's vertex and the length of the diagonal of the rectangle (3) Size of the rectangular object (4) Rotation angle of rectangular object (5) Character color of rectangular text object (6) Background color of rectangular image object (7) Page number of printing paper In addition, in layout data 140, each rectangular object is printed. It is preferable to sort in the order in which they are performed.

The layout data 140 is stored in the processing data storage area 62 (see FIG. 2). After executing the layout process (S12 in FIG. 3), the printer 50 proceeds to S14. In S14, the first band is specified. Hereinafter, “n” is used as a code for specifying a band. The first band is “n = 0”, and thereafter, “n = 1”, “n = 2”, “n = 3”.
Briefly describe the band. The printer 50 rasterizes the print data 110 to create bitmap data. The printer 50 prints on printing paper based on the bitmap data. A method of starting printing after creating bitmap data of all the print data 110 is conceivable. However, in this case, a large-capacity memory capable of storing the bitmap data of all the print data 110 is required.
The printer 50 of the present embodiment employs a technique for creating bitmap data in band units in order to compress the memory capacity for storing bitmap data. The print data 110 is divided into a plurality of bands. 4 and 6, it is divided into five bands 120, 122, 124, 126 and 128. Bitmap data of each band 120 to 128 is created in the order of printing on the printing paper. When bitmap data of one band (for example, band 120) is created, printing of the band is started. While the band is being printed, bitmap data of the next band (for example, band 122) is created. Repeat until the last band. When bitmap data is created for each band, the bitmap data of the band for which printing has been completed can be erased, so that the memory capacity for storing the bitmap data can be compressed.

When the first band (band 120 in this embodiment) is specified in S14 of FIG. 3, the printer 50 determines the band area of the band 120 (S16). The band region is defined by two coordinates (0, n · hB), (w, (n + 1) · hB). “N” is a number that identifies a band. For the first band, n = 0. “HB” indicates a bandwidth (vertical length of one band in FIG. 6). The bandwidth hB may be a fixed value or a variable value. For example, the bandwidth hB may be changed based on the memory capacity, the size of the printing paper, the printing resolution, and the like. The bandwidth may be changed for each band or may be changed for each print data.
The two coordinates (0, n · hB) and (w, (n + 1) · hB) that define the band region are arranged on one diagonal line of the rectangular band. For example, the two coordinates defining the band 120 (n = 0) are (0, 0) and (w, hB). (0, 0) is the coordinates of the upper left vertex of the band 120, and (w, hB) is the coordinates of the lower right vertex of the band 120.

The printer 50 identifies an object included in the band area determined in S16 (S18). First, for each of the rectangular objects 142, 144, and 146, the printer 50 specifies the upper y coordinate (hereinafter referred to as “y1”) and the lower y coordinate (hereinafter referred to as “y2”). For example, in the case of the rectangular image object 142, y1 is 80 and y2 is 120 (see FIG. 7). For example, in the case of the rectangular image object 144, y1 is 130 and y2 is 190.
In S18, an object in which y1 or y2 is included between n · hB and (n + 1) · hB is specified. For example, in the case of the band 120, an object whose y1 or y2 is included between zero and hB is specified. In this embodiment, the rectangular image object 142 is specified.
If a plurality of rectangular objects are included in one band, all rectangular objects are specified in S18. For example, in the case of the band 126, six rectangular text objects 146 are specified.

The printer 50 selects one object from the object (group) specified in S18 (S20).
Next, the printer 50 determines whether or not the object selected in S20 needs to be downloaded from the Internet 86 (S22). That is, it is determined whether the object is a DL object. For example, in the case of the band 120, the rectangular image object 142 is selected in S20. In this case, YES is determined in S22. If YES in S22, the process proceeds to S24. If NO in S22, S24 and S26 are skipped and the process proceeds to S28.

The printer 50 determines whether or not the image data of the rectangular image object determined as YES in S22 has been downloaded (S24). As described above, the downloaded image data is stored in the DL object storage area 56 of FIG. In S <b> 24, YES is determined when the image data of the rectangular image object determined as YES in S <b> 22 is stored in the DL object storage area 56. If YES in S24, S26 is skipped and the process proceeds to S28. On the other hand, if NO in S24, the process proceeds to S26.
In S26, an image object (image data) is downloaded from the Internet 86 (S26). For example, the rectangular image object 142 included in the band 120 includes the address of the server 100 (see FIG. 2). The printer 50 accesses the server 100 and downloads image data of the rectangular image object 142. The printer 50 stores the downloaded image data in the DL object storage area 56.

In S28, rasterization of the object selected in S20 is executed. That is, for each coordinate in the area occupied by the object, the size (or no dot) and color of the dot printed at that coordinate are determined. The density of the coordinate group depends on the printing resolution. Rasterization can be executed using various known methods. For example, rasterization can be performed using a halftone process, an error diffusion method, a dither method, or the like.
For example, in the case of the band 120, the printer 50 rasterizes the rectangular image object 142 stored in the DL object storage area 56. The bitmap data of the rectangular image object 142 obtained by rasterization is stored in the first bitmap data storage area 58 (see FIG. 2). Thereby, the bitmap data of the band 120 is created.

The bitmap data of the band 122 that is rasterized next to the band 120 is stored in the second bitmap data storage area 60 (see FIG. 2). Further, the bitmap data of the band 124 is stored in the first bitmap data storage area 58. In this case, the bitmap data of the band 120 is erased from the first bitmap data storage area 58. The bitmap data of the band 126 is stored in the second bitmap data storage area 60. In this case, the bitmap data of the band 122 is erased from the second bitmap data storage area 60. The bitmap data of the band 128 is stored in the first bitmap data storage area 58. In this case, the bitmap data of the band 124 is erased from the first bitmap data storage area 58.
The bitmap data of each band 120 to 128 is alternately stored in the first bitmap data storage area 58 and the second bitmap data storage area 60.

The printer 50 determines whether or not the object rasterized in S28 is included in the band in which the next bitmap data is created (S30). This process is determined as YES when the y coordinate (y2) of the lower end of the object rasterized in S28 is larger than (n + 1) · hB. For example, the rectangular image object 142 of the band 120 is not included in the band 122. In this case, NO is determined in S30.
Note that the process of S30 is executed only when the object rasterized in S28 is a rectangular image object. If the object rasterized in S28 is a rectangular text object, S30 and S32 are skipped.
If NO in S30, the printer 50 deletes the image data of the rectangular image object rasterized in S28 from the DL object storage area 56 (S32). If S30 is YES, S32 is skipped.

The printer 50 determines whether there is an object that has not been rasterized among the objects identified in S18 (S34). For example, the band 120 includes only one rectangular image object 142 and does not include other objects. In this case, NO is determined in S34.
On the other hand, if YES in S34, the printer 50 selects the next object (S36), and executes the processing from S22 on for the selected object.

  In the case of NO in S34, printing is performed on printing paper based on the bitmap data stored in the first bitmap data storage area 58 or the second bitmap data storage area 60 (S38). For example, the bitmap data of the band 120 is stored in the first bitmap data storage area 58. For this purpose, the print processing of the band 120 is executed based on the bitmap data stored in the first bitmap data storage area 58. The printing process in S38 is performed when the control device 52 issues an instruction to the printing device 74 (see FIG. 2).

When printing is started in S38, the printer 50 determines whether or not the next band exists (S40). For example, when S16 to S38 are completed for the band 120, since the next band 122 exists, YES is determined in S40.
If YES in S40, the printer 50 identifies the next band (S42). For example, when S16 to S38 are completed for the band 120, the band 122 is specified. Next, the printer 50 determines whether or not the band specified in S42 is beyond the end of one printing sheet. (S44). This process is determined to be YES when n · hB is larger than h (vertical length of the printing paper).
If YES in S44, it is determined to print on the next printing paper (S46). In this case, the number (n) specifying the band is cleared to zero. If S46 is completed or if NO in S44, the process proceeds to S16. Thereby, the process of S16-S38 is performed about the following band.

The processes of S16 to S38 described above are executed for each of the bands 122 to S128.
The contents of the processing executed for the band 122 will be briefly described. This process is executed while the bitmap data of the band 120 is printed on the printing paper.
In S18, the rectangular image object 144 (image object 114) is specified. In S22, YES is determined. In S24, NO is determined. In S26, the image data of the rectangular image object 144 is downloaded. This image data is stored in the DL object storage area 56.
In S28, the image data of the rectangular image object 144 is rasterized. As shown in FIG. 6, the rectangular image object 144 is disposed across the band 122 and the band 124. In this case, only the portion included in the band 122 in the bitmap data obtained by rasterizing the rectangular image object 144 is stored in the second bitmap data storage area 60. Thereby, the bitmap data of the band 122 is created.
In S30, YES is determined. This is because the rectangular image object 144 is included in the band 124 to be rasterized next. In this case, the downloaded image data is not erased (S32 is skipped).

Next, the contents of the processing executed for the band 124 will be briefly described. This process is executed while the bitmap data of the band 122 is being printed on the printing paper.
In S18, the rectangular image object 144 (image object 114) is specified. In S22, YES is determined. In S24, YES is determined. This is because the image data of the rectangular image object 144 is downloaded when the bitmap data of the band 122 is created.
In S28, the image data of the rectangular image object 144 is rasterized. Only the portion included in the band 124 in the bitmap data obtained by rasterizing the rectangular image object 144 is stored in the first bitmap data storage area 60. That is, the bitmap data of the band 120 is deleted, and the bitmap data of the band 124 is stored. Thereby, the bitmap data of the band 124 is created. Since the printing of the band 120 has been completed, there is no problem even if the bitmap data of the band 120 is deleted.
In S30, NO is determined. This is because the rectangular image object 144 is not included in the band 126. In this case, the image data of the rectangular image object 144 is deleted from the DL object storage area 56 (S32).

The contents of the processing executed for the band 126 will be briefly described. This process is executed while the bitmap data of the band 124 is being printed on the printing paper.
In S18, six rectangular text objects 146 are specified. The processing from S22 onward is executed for each object 146.
In S22, NO is determined. In S28, the rectangular text object 146 is rasterized. The bitmap data obtained by rasterizing is stored in the second bitmap data storage area 60. That is, the bitmap data of the band 122 is deleted, and the bitmap data of the band 126 is stored. Thereby, the bitmap data of the band 126 is created.
S30 and S32 are skipped. In S <b> 34, NO is determined when processing has been completed for all six objects 146.

  Note that the band 128 does not include an object. That is, no object is specified in S18. In this case, S20 to S38 are skipped and the process proceeds to S40. In S40, NO is determined. This is because the band 128 is the last band. As a result, all processing is completed.

In this embodiment, a rectangular image object 144 (image object 114) is disposed across the band 122 and the band 124 (see FIGS. 4 and 6). The printer 50 does not erase the image data of the rectangular image object 144 from the DL object storage area 56 even if the image data of the rectangular image object 144 is rasterized in order to create the bitmap data of the band 122. For this reason, when creating the bitmap data of the band 124, it is not necessary to download the image data of the rectangular image object 144 anew. The same DL object is prevented from being downloaded multiple times. The printer 50 can efficiently rasterize print data.
In addition, when the printer 50 rasterizes the image data of the rectangular image object 144 in order to create the bitmap data of the band 124, the printer 50 deletes the image data of the rectangular image object 144 from the DL object storage area 56. Occurrence of an event that unnecessary image data is stored for a long time is suppressed. The printer 50 can efficiently use the memory (DL object storage area 56).
In the present embodiment, the objects 112 to 116 included in the print data are converted into rectangular objects 142 to 146. Each object is positioned by simple rectangular coordinates. For this reason, the printer 50 can easily identify the objects included in the band. That is, the processing of S18 and S30 in FIG. 3 can be easily executed.

(Modification of the first embodiment)
In the first embodiment, when the bitmap data of the band 122 is created, the entire image data of the rectangular image object 144 is rasterized (S28). A portion included in the band 122 is cut out from the bitmap data of the rectangular image object 144 obtained by rasterization, and the portion is stored in the second bitmap data storage area 60 (S28). Thereby, bitmap data of the rectangular image object 144 is created for the band 122.
Further, when the bitmap data of the band 124 is created, all of the image data of the rectangular image object 144 is rasterized again (S28). A portion included in the band 124 is cut out from the bitmap data of the rectangular image object 144 obtained by rasterization, and the portion is stored in the first bitmap data storage area 58 (S28). Thereby, the bitmap data of the rectangular image object 144 is created for the band 124. Thereafter, the image data of the rectangular image object 144 is deleted from the DL object storage area 56 (S32).
These processes can be modified as follows.

When the bitmap data of the band 122 is created, all of the image data of the rectangular image object 144 is rasterized. A portion included in the band 122 is cut out from the bitmap data of the rectangular image object 144 obtained by rasterization, and the portion is stored in the second bitmap data storage area 60. Up to this point, the process is the same as in the first embodiment. Bit map data of the rectangular image object 144 obtained by rasterization is stored in the DL object storage area 56. In this case, it is preferable to delete the image data (downloaded data) of the rectangular image object 144 from the DL object storage area 56.
When the bitmap data of the band 124 is created, the image data of the rectangular image object 144 is not rasterized again. A portion included in the band 124 is cut out from the bitmap data of the rectangular image object 144 stored in the DL object storage area 56, and the portion is stored in the first bitmap data storage area 58. Thereby, the bitmap data of the rectangular image object 144 is created for the band 124. Thereafter, the bitmap data of the rectangular image object 144 is deleted from the DL object storage area 56.
According to this modification, it is possible to suppress the occurrence of an event that the same image data is rasterized a plurality of times. According to this modification, bitmap data can be created efficiently.

(Second embodiment)
In this embodiment, the process executed by the printer 50 is different from that in the first embodiment. 8 and 9 show flowcharts of processing executed by the printer 50 of this embodiment.
S50 and S52 are the same processes as S10 and S12 of FIG. For this reason, explanation about S50 and S52 is omitted.
The printer 50 selects one rectangular object from each rectangular object created in S52 (S54).
Next, the printer 50 determines whether or not the rectangular object selected in S54 is an object that needs to be downloaded (S56). That is, it is determined whether or not the rectangular object selected in S54 is a rectangular image object. If YES here, the number of the band area including the rectangular image object is calculated (S58). In this process, the coordinate y2 of the lower end of the rectangular image object is divided by the bandwidth hB. The decimal part is rounded down.
For example, in the case of the rectangular image object 142 of FIG. 6, the coordinate y2 of the lower end is 120 (see FIG. 7). 120 is divided by the bandwidth hB. As a result, a solution of “zero” is obtained. This solution “zero” is the band region number (n = 0). For example, the rectangular image object 144 in FIG. 6 is included in both the band 122 and the band 124. In this case, the number (n = 2) of the band 124 including the lower end coordinate C4 is obtained in S58.

Next, the printer 50 registers the URL on the Internet (that is, the download destination address) where the image data of the rectangular image object determined to be YES in S56 is stored in the position data storage area 64 (see FIG. 2). It is judged whether it is (S60).
If NO in S60, information in which the image data download destination address, page number, and band area number are associated with each other is stored in the position data storage area 64 (S64). The address is included in the rectangular image object. The layout data 140 (see FIG. 7) of the present embodiment includes data of page numbers (not shown) of printing paper. For this reason, the printer 50 can specify the page number of the printing paper containing the rectangular image object determined to be YES in S56. The band area number is obtained in S58.
For example, in the case of the rectangular image object 142 in FIG. 6, information in which the address, the page number “1”, and the band area number “0” are associated is stored in the position data storage area 64. FIG. 10 shows an example of the stored contents of the position data storage area 64.
The situation where S62 is determined as YES in S60 and S62 is executed will be described later.

In S66, it is determined whether or not the next object exists. If YES here, the printer 50 selects the next object (S68).
The printer 50 executes the processes of S56 to S64 for the object selected in S68. The printer 50 executes the processes of S56 to S64 for each of all the objects included in the layout data 140.
In the second and subsequent processing of S56 to S64 (processing of S56 to S64 executed via S68), YES may be determined in S60. That is, when two or more same image objects are included in the layout data 140, YES may be determined in S60.
If YES in S60, either the rectangular image object previously registered in the position data storage area 64 or the rectangular image object selected in S68 (this is the same as the previously registered one). It is determined whether the rasterization is performed first. If the former is rasterized after the latter, YES is determined in S62. In this case, S64 is skipped. That is, the information (address, page number, band area number) of the rectangular image object selected in S68 is not stored in the position data storage area 64. On the other hand, if the latter is rasterized after the former, NO is determined in S62. In this case, information (address, page number, band area number) of the rectangular image object selected in S68 is stored in the position data storage area 64 (S64). In this case, the information on the previously registered rectangular image object is deleted from the position data storage area 64.
These processes can be rephrased as follows. That is, when two or more identical image objects are included in the layout data 140, the information of the image object to be rasterized first is not stored in the position data storage area 64, but the image object to be rasterized later is not stored. Information is stored in the position data storage area 64.

When the processes of S56 to S64 are executed for all the objects 142, 144, and 146 included in the layout data 140, it is determined as NO in S66. In this case, the process proceeds to S70 of FIG.
The processing of S70 to S102 is almost the same as the processing of S14 to S46 in FIG. Here, only differences from the first embodiment will be described. The process of S86 is different from S30 of FIG. In S86, it is determined whether or not the object (rectangular image object) selected in S76 or S92 is included in a band to be rasterized later. This process is executed by referring to the stored contents of the position data storage area 64.
For example, when the process of S86 is executed for the rectangular image object 144 of the band 122 (n = 1) in FIG. 6, the position data storage area 64 is searched from the address of the rectangular image object 144. Thereby, the page number and the band area number associated with the address of the rectangular image object 144 are specified. Here, page “1” and band area number “n = 2” are specified. The band 122 currently processed is the band area number “n = 1” of the page “1” (n = 1). For this reason, the printer 50 determines that the rectangular image object 144 is used in a later band. That is, YES is determined in S86.
Further, for example, when the process of S86 is executed for the rectangular image object 144 of the band 124 (n = 2) in FIG. 6, the position data storage area 64 is searched from the address of the rectangular image object 144. As a result, the page number “1” and the band area number “n = 2” associated with the address of the rectangular image object 144 are specified. The band 124 currently being processed is the band area number “n = 2” of the page “1”. For this reason, the printer 50 determines that the rectangular image object 144 is not used in a later band. That is, NO is determined in S86.

Also in this embodiment, it is possible to determine whether or not an image object is included in a band to be rasterized later. In particular, in this embodiment, even when two or more identical image objects are arranged apart from each other in the print data (when there is a band that does not include the image object between one and the other), The image data of the image object is downloaded only once.
The printer 50 of this embodiment can efficiently create bitmap data in band units from print data including a DL object.

Specific examples of the present invention have been described in detail above, but these are merely examples and do not limit the scope of the claims. The technology described in the claims includes various modifications and changes of the specific examples illustrated above.
Further, the technical elements described in the present specification or drawings exhibit technical usefulness alone or in various combinations, and are not limited to the combinations described in the claims at the time of filing. In addition, the technology illustrated in the present specification or the drawings achieves a plurality of objects at the same time, and has technical utility by achieving one of the objects.

An example of data to be rasterized is shown. 1 illustrates a configuration of a printer according to an embodiment. 2 shows a flowchart of processing executed by a printer. A visual representation of the print data is shown. The data structure of print data is shown. Shows a visual representation of layout data. The data structure of layout data is shown. 7 shows a flowchart of processing executed by a printer (second embodiment). The flowchart of the process which a printer performs is shown (continuation of FIG. 8). An example of the stored contents of the position data storage area is shown.

Explanation of symbols

10: Data 12, 14, 16: Object 20: DL objects 30, 32, 34, 36, 38: Band 50: Printer 52: Control device 54: Storage device 66: Display device 68: Operating device 70: Slot unit 72: Memory card 74: Printing device 76: Input / output port 86: Internet 110: Print data 112, 114: Image object 116: Text object 120, 122, 124, 126, 128: Band 140: Layout data 142, 144: Rectangular image object 146: Rectangular text object

Claims (8)

A rasterizing device that is used by being connected to a communication network and that can rasterize data including DL objects that need to be downloaded from the communication network.
A first storage area capable of storing downloaded DL objects;
A rasterizer that rasterizes data and creates bitmap data in order in bands,
The rasterizer performs the following processing for a band including a predetermined DL object:
(1) If the predetermined DL object is not stored in the first storage area, the predetermined DL object is downloaded and stored in the first storage area, and the predetermined DL object is stored in the first storage area. If not, the predetermined DL object is not downloaded,
(2) rasterizing the predetermined DL object stored in the first storage area;
(3) When the predetermined DL object is not included in a band in which bitmap data is created after the band, the bitmap data of the predetermined DL object is created for the band from the first storage area. If the predetermined DL object is erased and the predetermined DL object is included in a band in which bitmap data is generated after the band, the bitmap data of the predetermined DL object is generated for the band. A rasterizing apparatus that executes a process of not deleting the predetermined DL object from the first storage area. In the process (3), the rasterizer
Determining whether the predetermined DL object is included in a band in which bitmap data is created next to the band;
When the predetermined DL object is not included in a band in which bitmap data is created next to the band, the bitmap data of the predetermined DL object is created for the band from the first storage area. Delete the DL object
When the predetermined DL object is included in the band in which the bitmap data is created next to the band, the predetermined storage object is created from the first storage area even if the bitmap data of the predetermined DL object is created for the band. The rasterizing apparatus according to claim 1, wherein the DL object is not erased. In the process (3), the rasterizer
Determining whether the predetermined DL object is included in any band in which bitmap data is created after the band;
If the predetermined DL object is not included in any band in which bitmap data is created after the band, the bitmap data of the predetermined DL object is created for the band from the first storage area. Delete the predetermined DL object;
When the predetermined DL object is included in any band for which bitmap data is created after the band, the bitmap data of the predetermined DL object is created from the first storage area for the band. The rasterizing apparatus according to claim 1, wherein the predetermined DL object is not deleted. The apparatus further includes a device for creating conversion data by converting each object included in the data into a rectangular object positioned by the coordinates of a vertex of a rectangle including the shape of the object,
The rasterizer creates bitmap data sequentially in band units from the created conversion data,
The rasterizer according to any one of claims 1 to 3, wherein the rasterizer specifies an object included in each band based on the coordinates. A second storage area capable of storing bitmap data for at least one band; and a third storage area capable of storing bitmap data for at least one band;
The rasterizer according to any one of claims 1 to 4, wherein the rasterizer stores bitmap data of each band alternately in the second storage area and the third storage area. A printer comprising the rasterizing device according to any one of claims 1 to 5 and a printing device,
The printer is
(A) When the bitmap data of the first band is created by the rasterizing device, printing on the print medium based on the bitmap data of the band,
(B) When bitmap data of the next band is created by the rasterizing device, printing is performed on a print medium based on the bitmap data of the band,
(C) The printer described in (B) is repeated until printing on a print medium based on the bitmap data of the last band. A computer program for realizing an apparatus for rasterizing data including a DL object that needs to be downloaded from a communication network,
The computer program causes a computer mounted on the rasterizing apparatus to execute a process of rasterizing data and sequentially creating bitmap data in band units,
In the rasterization process, for the band including a predetermined DL object, the following process is performed:
(1) If the predetermined DL object is not stored in the predetermined storage area, the predetermined DL object is downloaded and stored in the predetermined storage area, and the predetermined DL object is stored in the predetermined storage area. Is stored in, the predetermined DL object is not downloaded,
(2) rasterizing the predetermined DL object stored in the predetermined storage area;
(3) If the predetermined DL object is not included in a band in which bitmap data is created after the band, the predetermined storage area is created when bitmap data of the predetermined DL object is created for the band. If the predetermined DL object is deleted from the band and the predetermined DL object is included in a band in which the bitmap data is generated after the band, the bitmap data of the predetermined DL object is generated for the band. The computer program is characterized in that a process of not deleting the predetermined DL object from the predetermined storage area is executed. It is a method of rasterizing data including DL objects that need to be downloaded from a communication network and creating bitmap data in order of bands,
For a band containing a given DL object, the following steps:
(1) If the predetermined DL object is not stored in the predetermined storage area, the predetermined DL object is downloaded and stored in the predetermined storage area, and the predetermined DL object is stored in the predetermined storage area. Is stored in, the predetermined DL object is not downloaded,
(2) rasterizing the predetermined DL object stored in the predetermined storage area;
(3) If the predetermined DL object is not included in a band in which bitmap data is created after the band, the predetermined storage area is created when bitmap data of the predetermined DL object is created for the band. If the predetermined DL object is deleted from the band and the predetermined DL object is included in a band in which the bitmap data is generated after the band, the bitmap data of the predetermined DL object is generated for the band. And a method of performing rasterization, wherein the predetermined DL object is not erased from the predetermined storage area.

Images