Abstract:
An image description data processing method is provided for execution in an apparatus including a holding unit configured to hold image description data described in an image description language including one of a page description language and a structured language. The method includes acquiring first image description data from the holding unit; extracting a description of a first rendering command from the acquired first image description data; calculating the description of the first rendering command to replace the description of the first rendering command with a description of a second rendering command; and storing second image description data containing the description of the second rendering command in the holding unit.

Description:
BACKGROUND OF THE INVENTION  
       [0001]     1. Field of the Invention  
         [0002]     The present invention relates to a method, an apparatus, and a program for processing image description data expressed in an image description language.  
         [0003]     2. Description of the Related Art  
         [0004]     A result of processing data by an information processing apparatus has conventionally been output at high quality to a laser printer or the like. Thus, a parser for a page description language which is one of an image description language type is mounted on a printer, and parsing of page description data is executed by the printer to perform rendering. A representative page description language is PostScript™ provided by Adobe Systems Incorporated.  
         [0005]     Some of the existing page description languages have affine transformation commands prepared for graphics and characters in addition to commands for designating coordinates and colors. Affine transformation processing is geometrical transformation processing of graphics which includes enlargement, reduction, rotation, translation processing, and the like for graphics and characters. In many cases, the processing is generally accompanied by a linear transformation and a translation. The affine transformation processing can be carried out in multiple manners. For example, processing for executing a translation after transformation of rotation for graphics or characters can be expressed by the existing page description language.  
         [0006]     Conventionally, when a rendering processing command described in a page description data contains an affine transformation processing command, an iterative calculation is performed in, e.g., a printer, to perform rendering processing according to the description.  FIGS. 11A and 11B  show an example of rendering a rectangle by executing an affine transformation in multiple manners according to description specifications of PostScript.  FIG. 11A  shows page description data described in PostScript language, while  FIG. 11B  shows a result of rendering processing.  
         [0007]     Referring to  FIG. 11A , an affine transformation processing command is executed at 3rd to 5th lines, and a graphic is rendered at 7th to 11th lines. The graphic designated to be rendered at the 7th to 11th lines is a rectangle parallel to X and Y axes and having one apex set as an origin. However, as shown in  FIG. 11B , an actually rendered graphic becomes a parallelogram due to the affine transformation processing performed at the 3rd to 5th lines.  
         [0008]     Furthermore, in the existing page description languages, a character string can be rendered with a layout designated.  FIGS. 12A and 12B  show a description example of head, center, and tail alignments relative to designated points.  FIG. 12A  shows page description data described in PostScript language, and  FIG. 12B  shows a result of executing rendering processing.  
         [0009]     Referring to  FIG. 12A , definition is made for a center alignment at 5th to 10th lines, and a right alignment at 12th to 17th lines. At 19th to 21st lines, the same X coordinates are designated. Additionally, a layout is calculated for a designated point by description to refer to a center or right alignment, so that a rendering result such as that shown in  FIG. 12B  can be obtained. Examples of enlarging a pitch between characters as shown in  FIGS. 14A and 14B  and arranging characters on a curve (circular arc) as shown in  FIGS. 15A and 15B  are discussed in “POSTSCRIPT Tutorial &amp; Cookbook” (written by Adobe Systems, and edited by ASCII Publishing Technical Division).  
         [0010]     Data described as the page description data shown in  FIGS. 12A, 14A , and  15 A have conventionally been subjected to rendering processing by internally calculating a layout in an image forming apparatus such as a printer.  
         [0011]     Recently, specifications of Scalable Vector Graphics (SVG) have been formulated by World Wide Web Consortium (W3C), and its application to a page description language is now under study. As in the case of PostScript™, SVG can render given graphics or characters by designating coordinates and colors or affine transformation processing. According to the specifications, designation methods for character layouts are diverse, and can be flexibly designated.  
         [0012]     Conventional page description languages, structured languages, such as SVG, etc., are referred to as image description languages. As described above, when an affine transformation command is described in a page description language, processing is iterated, and a tree structure may be described deeper than necessary even in a structured language. Such unnecessary processing increases latency, and thereby, reduces the overall performance of the information processing apparatus.  
         [0013]     To overcome the aforementioned drawbacks, there has been an attempt to reduce unnecessary processing due to, for instance, when an affine transformation command is described in a page description language. For example, in Japanese Patent Application Laid-open Nos. 2002-108850 and 2004-240491, in a structured language, layers of a tree structure are reduced or a structure transformation is carried out. However, the process performed in Japanese Patent Application Laid-open Nos. 2002-108850 and 2004-240491 have disadvantages because they do not reduce processing load of a processor suffering from rendering complicated image. It would be desirable to provide efficient preprocessing for rendering an image described with structured language data.  
       SUMMARY OF THE INVENTION  
       [0014]     According to an aspect of the present invention, an image description data processing method is provided for execution in an apparatus including a holding unit configured to hold image description data described in an image description language including one of a page description language and a structured language. The method includes acquiring first image description data from the holding unit; extracting a description of a first rendering command from the acquired first image description data; calculating the description of the first rendering command to replace the description of the first rendering command with a description of a second rendering command; and storing second image description data containing the description of the second rendering command in the holding unit.  
         [0015]     According to another aspect of the present invention, the image description data processing method may further include sending the second image description data to an image forming apparatus. According to another aspect of the present invention, the image description data processing method may further include forming an image rendered based on the second image description data.  
         [0016]     According to another aspect of the present invention, the image description data may be described according to specifications of a structured language including Extensible Markup Language (XML). According to another aspect of the present invention, the image description data may be described according to specifications of a page description language including PostScript™.  
         [0017]     According to yet another aspect of the present invention, the description of the rendering command describes a command of rendering at least one of a rectangle, an ellipse, a circle, an elliptic arc, a circular arc, a line, a polygon, a polyline, a curve, a text, or a combination thereof. Moreover, according to another aspect of the present invention, the description of the rendering command includes an affine transformation command. Additionally, according to another aspect of the present invention, the description of the rendering command may include a layout command.  
         [0018]     Furthermore, according to yet another aspect of the present invention, the replacement calculation may include executing a calculation to change the number of descriptions of the first rendering command. while in another aspect of the present invention, the replacement calculation may include executing a matrix calculation for the first rendering command. Moreover, according to yet another aspect of the present invention, the replacement calculation may include executing a replacement calculation according to a performance of the image forming apparatus when there are a plurality of description methods to change the number of descriptions of the first rendering command.  
         [0019]     According to another aspect of the present invention, an apparatus is provided for processing image description data described in an image description language including one of a page description language and a structured language. Here, the apparatus includes a holding unit configured to hold the image description data; an acquisition unit configured to acquire first image description data from the holding unit; an extraction unit configured to extract a description of a first rendering command from the first image description data; a replacement calculation unit configured to calculate the description of the first rendering command to replace the description of the first rendering command by a description of a second rendering command; and a storage unit configured to store second image description data containing the description of the second rendering command in the holding unit.  
         [0020]     And, according to yet another aspect of the present invention, a program for execution in an apparatus including a holding unit configured to hold image description data described in an image description language including one of a page description language and a structured language is provided. The program includes an acquisition step of acquiring first image description data from the holding unit; an extraction step of extracting a description of a first rendering command from the first image description data; a replacement calculation step of calculating the description of the first rendering command to replace the description of the first rendering command by a description of a second rendering command; and a storage step of storing second image description data containing the description of the second rendering command in the holding unit.  10020 ] Furthermore, according to yet another aspect of the present invention, a computer readable medium is provided which contains computer-executable instructions for execution in an apparatus including a holding unit configured to hold image description data described in an image description language including one of a page description language and a structured language. Here, the medium includes computer-executable instructions for acquiring first image description data from the holding unit; computer-executable instructions for extracting a description of a first rendering command from the first image description data; computer-executable instructions for calculating the description of the first rendering command to replace the description of the first rendering command by a description of a second rendering command; and computer-executable instructions for storing second image description data containing the description of the second rendering command in the holding unit.  
         [0021]     Further features and aspects of the present invention will become apparent from the following detailed description of exemplary embodiments with reference to the attached drawings. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0022]     The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate exemplary embodiments of the invention and, together with the description, serve to explain the principles of the invention.  
         [0023]      FIG. 1  is a block diagram showing an exemplary configuration of an information processing apparatus which includes a page description data processor according to embodiments of the present invention.  
         [0024]      FIG. 2  is a block diagram showing an exemplary configuration of a page description data processor according to a first embodiment of the present invention.  
         [0025]      FIG. 3  is a flowchart showing an exemplary processing flow of the page description data processor according to the first embodiment of the present invention.  
         [0026]      FIG. 4  is a diagram showing a portion of page description data when SVG is used as a page description language according to the first embodiment of the present invention.  
         [0027]      FIG. 5  is a schematic diagram showing exemplary page description data replacement processing in the page description data processor according to the first embodiment of the present invention.  
         [0028]      FIGS. 6A and 6B  are supplementary diagrams of the page description data replacement processing in the page description data processor according to the first embodiment of the present invention.  
         [0029]      FIG. 7  is a block diagram showing an exemplary configuration of a page description data processor according to a second embodiment of the present invention.  
         [0030]      FIG. 8  is a flowchart showing an exemplary processing flow of the page description data processor according to the second embodiment of the present invention.  
         [0031]      FIG. 9  is a diagram showing a portion of page description data when SVG is used as a page description language according to the second embodiment of the present invention.  
         [0032]      FIG. 10  is a schematic diagram showing exemplary page description data replacement processing in the page description data processor according to the second embodiment of the present invention.  
         [0033]      FIGS. 11A and 11B  are diagrams showing an example of page description data for executing a graphic rendering processing command which accompanies multiple affine transformation processing, and its rendering result.  
         [0034]      FIGS. 12A and 12B  are diagrams showing an example of page description data in which text rendering processing is laid out by relative head, center, and tail alignments with respect to a designated point, and its rendering result.  
         [0035]      FIGS. 13A and 13B  are diagrams each showing a calculation method when affine transformation processing is carried out in a general two-dimensional XY coordinate system.  
         [0036]      FIGS. 14A and 14B  are diagrams showing an example of page description data in which text rendering processing is laid out by enlarging a pitch between characters, and its rendering result.  
         [0037]      FIGS. 15A and 15B  are diagrams showing an example of page description data in which text rendering processing is laid out on a designated curve, and its rendering result.  
     
    
     DETAILED DESCRIPTION OF THE EMBODIMENTS  
       [0038]     The following description of the exemplary embodiments are merely illustrative in nature and is in no way intended to limit the invention, its application, or uses. Note that similar reference numerals and letters refer to similar items in the following figures, and thus once an item is defined in one figure, it may not be discussed for following figures. Exemplary embodiments will be described in detail below in accordance with the accompanying drawings.  
       First Exemplary Embodiment  
       [0039]      FIG. 1  is a block diagram showing an exemplary configuration of an information processing apparatus which includes a page description data processor according to an exemplary embodiment of the present invention. A CPU  101  is a system control unit which controls the apparatus. A ROM  102  stores a control program of the CPU  101  and various fixed data. A RAM  103  includes an SDRAM, a DRAM or the like to store program control variables, various frame buffers or the like. A communication control unit  104  carries out control of data communication executed through a communication interface  105 . The communication interface  105  can be an IEEE 1394 interface, a wired LAN interface, a wireless LAN interface or the like, and the embodiment is not limitative in this regard. A page description data processor  10  performs processing for replacing page description data stored in the RAM  103  by another page description data and storing another page description data in the RAM  103 .  
         [0040]      FIG. 2  is a block diagram showing an exemplary configuration of the page description processor  10  according to a first embodiment of the present invention. A page description data acquisition unit  201  acquires first page description data from the RAM  103 . A page description data interpretation unit  202  interprets the first page description data acquired by the page description data acquisition unit  201  for each rendering command. An affine transformation processing command extraction unit  205  extracts an affine transformation processing command contained in the rendering command divided by the page description data interpretation unit  202 . An affine transformation calculation unit  206  subjects the affine transformation processing command acquired by the affine transformation processing command extraction unit  205  to calculation processing. A page description data replacement unit  203  replaces the rendering command acquired by the page description data interpretation unit  202  by another rendering command based on a calculation result obtained by the affine transformation calculation unit  206  to generate second page description data. A page description data output unit  204  stores the second page description data generated by the page description data replacement unit  203  in the RAM  103 . Thus, the second page description data held in the RAM  103  is sent to an image forming apparatus such as a printer, and the image forming apparatus interprets the second page description data to form an image.  
         [0041]     Referring to  FIG. 3 , an exemplary processing flow of the page description data processor  10  according to the first embodiment of the present invention will be described next. First page description data to be input is stored in a buffer area secured in the RAM  103 . First, the page description data acquisition unit  201  acquires the first page description data from the buffer area of the RAM  103  (step S 302 ). The page description data interpretation unit  202  interprets the acquired first page description data to break it down into rendering commands (step S 303 ). Subsequently, the following processing is repeated for each rendering command (step S 304 ).  
         [0042]     First, it is determined whether the rendering command indicates affine transformation processing or processing including affine transformation processing (step S 305 ). If conditions are satisfied, the affine transformation processing command extraction unit  205  extracts an affine transformation processing command, the affine transformation calculation unit  206  carries out affine transformation calculation, and a calculation result is stored in the RAM  103  (step S 306 ). If the conditions are not satisfied, the processing of step S 306  is not executed. Next, for a rendering command currently targeted to be processed, the page description data replacement unit  203  replaces the page description data based on the affine transformation calculation result stored in the RAM  103  (step S 307 ). Further, the page description data output unit  204  stores a replacement result in the RAM  103  (step S 308 ).  
         [0043]     Next, the process of steps S 304  to S 308  will be described more in detail using, as an example, page description data shown in  FIG. 4 . The present invention does not specify any particular image description language. However, a case that uses SVG will be described herein. The page description data shown in  FIG. 4  is broken down into rendering processing commands.  
         [0044]      FIG. 5  is a schematic diagram showing the process of steps S 304  to S 308 . A stack  530  is an area for storing the affine transformation calculation result, and its initial state is vacant. As the page description data processing processes processing commands in read sequence, a processing command  502  is read. A transform attribute indicates an affine transformation processing command, and an attribute value indicates an affine transformation operation. In this case, as translate (150 200) is an affine transformation operation, this is acquired to be transformed into an internal form  522 . A transformation result is loaded on the stack  530 . This result is a stack state  532 . An affine transformation internal form of a top part of the stack  530  is denoted by  542 . At this time, as the processing command  502  is not a graphic rendering processing command, page description data replacement processing or page description data output processing is not carried out (step  572 ).  
         [0045]     Next, a processing command  503  is acquired to be similarly replaced by an affine transformation internal form  523 . As the stack  530  is no longer vacant at this time, the affine transformation internal form  542  of the top part of the stack  530  and the affine transformation internal form  523  are multiplied together to be newly loaded as an affine transformation internal form  543  on the stack  530 . Its result is a stack state  533 . In this case, as the processing command  503  is not a graphic rendering processing command, page description data replacement processing or page description data output processing is not carried out (step  573 ).  
         [0046]     A next processing command  504  is acquired. The processing command  504  contains an affine transformation processing command in a rectangle rendering command. First, the affine transformation processing command is extracted to be transformed into an affine transformation internal form  524 , and a result of multiplying it by the affine transformation internal form  543  of the top part of the stack  530  is loaded as a new affine transformation internal form  544  on the stack  530 . This result is a stack state  534  (step  574 ).  
         [0047]     Next, the rectangle rendering command of the processing command  504  is interpreted. According to the processing command  504 , a shape for a rectangle is designated. In the case of a rectangle, a shape is decided based on apex coordinates (x attribute and y attribute) of a left top, a width (width attribute), and a height (height attribute). Attribute values of x, y, width, and height are x, y, w, and h, an apex A is (x, y), an apex B is (x+w, y), an apex C is (x+w, y+h), and an apex D is (x, y+h). An area obtained by sequentially connecting apexes A-B-C-D-A by lines constitutes the shape. In an example shown in  FIG. 4 , A (−30, −20), B (30, −20), C (30, 20), and D (−30, −20) are set.  
         [0048]     Next, an affine transformation internal form  544  is acquired as the affine transformation internal form of the top part of the stack  530  at this time, and a result of multiplying it by the apex A is stored as an apex A′ in the RAM  103 . For the apexes B to D, similarly, apexes B′ to D′ are stored in the RAM  103 .  
         [0049]     Subsequently, the processing command  504  is replaced by referring to coordinate values of the apexes A′ to D′. Specifically, it is replaced by a path processing command. In SVG, the path processing command is described by a &lt;path&gt; element, and shape information is described by a d attribute. First, X and Y coordinates of the apex A′ are transformed into a character string, separated by a comma (,), and a d attribute command  512  is generated after a character “M”. X and Y coordinates of the apex B′ are transformed into a character string, separated by a comma (,), and a d attribute command  513  is generated after a character “L”. Similarly, X and Y coordinates of the apexes C′ and D′ are transformed into character strings, separated by commas (,), and d attribute commands  514  and  515  are generated after the character “L”. Lastly, a d attribute command  516  only for a character “Z” is generated to interconnect start and end points of a graphic. The d attribute commands  512  to  516  are serialized to acquire a d attribute value  511  (step  575 ).  
         [0050]     A processing command  510  acquired as a result is a replacement result of the processing command  504 . In other words, it is a replacement result of contents described at 2nd to 7th lines in  FIG. 4 .  
         [0051]     The rectangle rendering processing command by a &lt;rect&gt; element has been described. Similar processing can be carried out for another graphic rendering command or a rendering processing command such as a path (&lt;path&gt;) which is a rendering command capable of combining curves or lines. The graphic rendering commands include a circle (&lt;circle&gt;), an ellipse (&lt;ellipse&gt;), a polygon (&lt;polygon&gt;), a polyline (&lt;polyline&gt;), a line (&lt;line&gt;), and the like.  
         [0052]     A case where such replacement processing is effective will be described. For example, in an environment where the image forming apparatus always receives page description data processed by the page description processor of the embodiment, a necessary graphic rendering processing command is a type of a path. A program in the image forming apparatus can be reduced in weight.  
         [0053]     The method of replacing by the path rendering processing command which has removed all the affine transformation processing commands has been described. As another method, a method of removing multiple affine transformation commands, and replacing a rendering processing command by a processing command including 0 or 1 affine transformation processing command to output it without changing a graphic type of the rendering processing command will be described.  
         [0054]     In  FIG. 5 , the same process is carried out in steps  572  to  574 . Next, a rectangle rendering command of the processing command  504  is interpreted, and all groups of attribute names and attribute values except transform attributes are stored in the RAM  103 . Then, the same graphic processing command as that of the processing command  504  is generated, and information of all attributes stored in the RAM  103  is set as its attributes. The affine transformation internal form  544  of the top part of the stack  530  stored in the stack  530  by the processing command  504  is acquired to be designated as an SVG transform attribute. Specifically, when an affine transformation internal form expressed by a matrix of 3×3 is expressed as shown in  FIG. 6A , an expression of a character string shown in  FIG. 6B  becomes a transform attribute to be designated. Accordingly, in an example of the page description data shown in  FIG. 4 , a transform attribute value  591  is obtained. Subsequently, the transform attribute value  591  and the attribute information stored in the RAM  103  are combined to acquire a processing command  590  (step  576 ).  
         [0055]     The processing command  590  as a result is a replacement result of the processing command  504 . In other words, it is a replacement result of contents described at 2nd to 7th lines in  FIG. 4 .  
         [0056]     The replacement processing is effective when the image forming apparatus processes a specific graph at a high speed. For example, it is known that when image formation of a general ellipse is fast, a graph of an ellipse or circle affine transformation processing result always becomes a general ellipse. In this case, it is advised to leave information that an input rendering processing command is a rendering command of a circle or an ellipse, rather than performing path replacement, because it contributes more to achievement of a high speed of rendering processing in the image forming apparatus.  
       Second Exemplary Embodiment  
       [0057]     Next, page description data processing according to a second exemplary embodiment of the present invention, specifically, layout processing, will be described with reference to the accompanying drawings.  
         [0058]      FIG. 7  is a block diagram showing an exemplary configuration of a page description data processor according to the second embodiment of the present invention. A page description data acquisition unit  701  acquires first page description data. A page description data interpretation unit  702  interprets the first page description data acquired by the page description data acquisition unit  701  for each rendering command. A text layout processing command acquisition unit  705  acquires a text layout command contained in the text rendering command divided by the page description data interpretation unit  702 . A text layout calculation unit  706  subjects the text layout command acquired by the text layout command acquisition unit  705  to calculation processing. A page description data replacement unit  703  replaces the text rendering command acquired by the page description data interpretation unit  702  by another text rendering command based on a text layout calculation result obtained by the text layout calculation unit  706  to generate second page description data. A page description data output unit  704  stores the second page description data generated by the page description data replacement unit  703  in a RAM  103 .  
         [0059]     Referring to  FIG. 8 , an exemplary processing flow of the page description data processor  10  according to the second embodiment of the present invention will be described next. Page description data to be input is stored in a buffer area secured in the RAM  103 . First, the page description data acquisition unit  701  acquires the page description data from the buffer area of the RAM  103  (step S 801 ). The page description data interpretation unit  702  interprets the acquired page description data to break it down into processing commands (step S 802 ). Subsequently, the following processing is carried out for the divided processing commands in read sequence (step S 803 ).  
         [0060]     First, it is determined whether the processing command is a text rendering processing command (step S 804 ). If the processing command is not a text rendering processing command, it is directly output to the RAM  103  from the page description data output unit  704  (step S 808 ) without being subjected to replacement processing at the page description data replacement unit  703 .  
         [0061]     If the processing command is determined to be a text rendering processing command in step S 804 , a layout processing command contained in the text rendering processing command is extracted (step S 805 ). The layout processing command may not be clearly indicated, in the text rendering processing command. In many cases, however, there is an implicit rule, e.g., when a character string is rendered, it is laid out immediately after a last character is rendered. It is presumed here that the processing includes such an implicit layout rule. Next, layout calculation is carried out for each character to be rendered with the text rendering processing command (step S 806 ). Subsequently, the processing command is replaced by another processing command based on the layout calculation result (step S 807 ), and the replaced processing command is output from the page description data output unit  703  to the RAM  103  (step S 808 ).  
         [0062]     The process of steps S 803  to S 808  will be described more in detail using, as an example, page description data shown in  FIG. 9 . The present invention does not specify any particular page description language. However, a case that uses SVG will be described herein.  
         [0063]     The page description data shown in  FIG. 9  is a text rendering processing command at 2nd to 4th lines, which has contents of an instruction to render a character string of “ABCD” with the position of X and Y coordinates 10 and 100 set as a starting point. The dx attribute of the &lt;text&gt; element designates the amount of shifting a character in the X axis direction. Normally, the character string of “ABCD” is rendered in a closely-spaced state. However, a space can be generated between characters by designating the dx attribute. In this example, a space of 10 pixels is instructed to be generated between characters.  
         [0064]      FIG. 10  is a schematic diagram showing an exemplary processing flow. As the page description data shown in  FIG. 9  is determined to be a text rendering processing command, the processing command is input to a text rendering processing command acquisition unit  1001 . First, a layout parameter acquisition unit  1002  acquires attribute values of the x attribute, the y attribute, the dx attribute, and the font-size attribute, which are layout processing commands of the &lt;text&gt; element, transforms them into numerical values, and stores the numerical values in the RAM  103 . Then, a character string division processing unit  1003  divides the character string “ABCD” to be rendered into separate characters “A”, “B”, “C”, and “D”.  
         [0065]     Next, a layout calculation processing unit  1004  calculates a layout position of each character. First, coordinates (x1, y1) of the layout position of “A” are obtained. As “A” is a head of the character string, coordinates where a shifting amount dx[1] by the dx attribute is added to a starting point (x, y) of the character string in the layout parameter are coordinates to be obtained. In an example shown in  FIG. 9 , coordinates to be obtained are (20, 100) because x=10, y=100, and dx=10. Further, a width equivalent to one character of “A” is calculated. A character width may vary from one font type to another, and from one character to another. In this case, a description will be made by presuming a font where a fixed pitch font (font defined so that all characters are set equal in width) is used, and a font width is “20” when “20” is designated as a font size. A width w 1  of a font obtained here is equal to 20 pixels.  
         [0066]     Subsequently, coordinates (x2, y2) of the layout position of “B” are obtained. “B” is designated to be shifted from a position of rendering a last character in the X axis direction by +10 pitches by the dx attribute. Accordingly, the coordinates (x2, y2) of the layout position of “B” can be obtained by adding, to the layout position (x1, y1) of “A”, a width w 1  equivalent to one character of “A” and a shifting amount dx[2] by the dx attribute, which are thus (50, 100). Also, similar processing is carried out for “C” and “D” to obtain respective layout position coordinates C (x3, y3)=(80, 100), and D (x4, y4)=(110, 100).  
         [0067]     Next, the text rendering processing command is replaced based on a calculation result by the layout calculation processing unit  1004 . As the position calculation has been completed for “A”, “B”, “C”, and “D” at the layout calculation processing unit  1004 , these pieces of coordinate information are designated as the x attribute and the y attribute of the &lt;text&gt; element. By describing the x and y attributes to be x=“x1, x2, x3, x4” and y=“y1, y2, y3, y4”, a layout of the character string to be rendered can be designated. When the page description data shown as an example in  FIG. 9  is input, the text rendering processing command subjected to replacement processing is described as a text rendering processing command  1006  shown in  FIG. 10 , and the text rendering processing command  1006  is output to the RAM  103  by a text rendering processing command output unit  1005 .  
         [0068]     Through the above processing, without executing calculation processing regarding a text layout at the rendering processor, rendering can be carried out only by referring to the simply designated x and y attribute values, and a high speed of processing of the rendering processor can be achieved.  
         [0069]     The processing example of laying out a character string by enlarging the pitch between characters has been described. Even in other cases where a character string is arranged on a curve ( FIG. 15B ), or arranged by relative head, center, and tail alignments for the designated point ( FIG. 12B ), layout calculation and replacement can be carried out by the above-described method. In addition, in the case of rotating a character, such rotation processing can be performed by using the rotate attribute of the &lt;text&gt; element in SVG.  
       Other Exemplary Embodiments  
       [0070]     The present invention can be achieved by supplying a recording medium having program code of software recorded therein to realize the functions of the above-described embodiments to a system or an apparatus, and causing a computer (a CPU or an MPU) of the system or the apparatus to read and execute the program code stored in the recording medium. In this case, the program code read from the recording medium realizes the functions of the embodiments, and the recording medium storing the program code constitutes the present invention.  
         [0071]     The recording medium for supplying the program code includes, for example, a flexible disk, a hard disk, an optical disk, a magneto-optical disk, a CD-ROM, a CD-R, a magnetic tape, a nonvolatile memory card, a ROM, a DVD, and the like.  
         [0072]     By executing the program code read by the computer, the functions of the embodiments are realized as described above. The invention includes a case where an operating system (OS) or the like running on the computer executes a part or all of actual processing based on instructions of the program code, and the functions of the embodiments are realized through the processing.  
         [0073]     The present invention includes a case where the program code read from the recording medium is written in a memory disposed in a function expansion board inserted into the computer or a function expansion unit connected to the computer, then a CPU or the like disposed in the function expansion board or the function expansion unit executes a part or all of actual processing based on the instructions of the program code, and the functions of the embodiments are realized through the processing.  
         [0074]     While the present invention has been described with reference to exemplary embodiments, it is to be understood that the invention is not limited to the disclosed exemplary embodiments. The scope of the following claims is to be accorded the broadest interpretation so as to encompass all modifications, equivalent structures, and functions.  
         [0075]     This application claims priority from Japanese Patent Application No. 2005-163964 filed Jun. 3, 2005, which is hereby incorporated by reference herein in its entirety.