Abstract:
An authoring tool is enabled to create special effects on an image using a color scale. A pattern file is used to map the image to the desired effect. By assigning meaning to one or more of the colors in the color scale, an image will be produced in accordance with the pattern file and the selected colors.

Description:
FIELD OF THE INVENTION 
     This invention relates in general to computer software, and in particular to a method and system for using color information in a file to perform special effects on an image. 
     BACKGROUND OF THE INVENTION 
     In the current world of advertising, movies and television, special effects can make or break a product. Computers are being used more and more all the time to create special effects, and users, as well as viewers, are becoming more discriminatory in what they will accept when it comes to what they see and create. 
     Computer authoring tools are one way users can add special effects to images. Special effects may include a fade in or fade out and a wipe right, etc. The currently available authoring tools have a rather inflexible approach to the creation of special effects due inherently to the methods used to draw an image. 
     For example, authoring tools like Director by Macromedia, Premiere by Adobe and Freelance Graphics by Lotus Development Corp. only support a limited number of pre-programmed transitions/dissolves. These tools typically use either an algorithm or a table to make transitions/effects. These limited number of effects are coded into the product&#39;s tools, and the user is unable to create any others. 
     The tools that use an algorithm are hard pressed to do anything beyond a simple transition. For example, if the user wants an image to transition into view by way of several spirals and a star, the math for computing such a display is both time consuming and complex. The level of complexity increases as any other characteristic, such as opacity, is added to when the image pixel is to become visible. 
     The tools that use a table method require a fixed table specifying when each image pixel is to become visible. Additional tables must be added for each and every other characteristic the user wants the image to display. These tables must be prepared and stored in the program for use when a transition is desired. 
     Thus, there is a need for a simple to use method and system for adding user defined transition patterns to create special effects. 
     SUMMARY OF THE INVENTION 
     The present invention disclosed herein comprises a method and system for using color to create special effects on an image which eliminates problems associated with prior special effect methods. The present invention allows the use of a color scale to produce any desired effect on an image. 
     In accordance with one aspect of the invention, a method is provided for creating on a computer system special effects on an image using color information. A color is associated with an effects property defined by a pattern file. An image is then mapped to the pattern file. The image is displayed on the computer system in accordance with the effects property, as applied by the pattern file. 
     It is a technical advantage of the present invention that special effects may be created by a user in any desired fashion. By assigning any known characteristic or effect to a color, the user can produce a special effect on an image in whatever fashion their imagination can devise. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     For a more complete understanding of the present invention and for further advantages thereof, reference is now made to the following Detailed Description taken in conjunction with the accompanying drawings, in which: 
     FIG. 1 is a pictorial representation of a data processing system which may be utilized to implement a method and system of the present invention; 
     FIG. 2 is a graphical representation of an editor which may be used to implement the present invention; 
     FIG. 3 is a graphical representation of the use of the editor of FIG. 3 in accordance with the present invention; 
     FIG. 4 is a sample of a pattern file for use with the present invention; 
     FIGS. 5A,  5 B,  5 C and  5 D illustrate a fade-in using the method of the present invention; 
     FIG. 6 illustrates an example of a more complex pattern file that may be used to implement special effects in accordance with the present invention; and 
     FIGS. 7 and 8 are high level flowcharts illustrating the present invention. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Referring to FIG. 1, there is depicted a graphical representation of a data processing system  8 , which may utilized to implement the present invention. As may be seen, data processing system  8  may include a plurality of networks, such as Local Area Networks (LAN)  10  and  32 , each of which preferably includes a plurality of individual computers  12  and  30 , respectively. Of course, those skilled in the art will appreciate that a plurality of Intelligent Work Stations (IWS) coupled to a host processor may be utilized for each such network. As is common in such data processing systems, each individual computer may be coupled to a storage device  14  and/or a printer/output device  16  and may be provided with a pointing device such as a mouse  17 . 
     The data processing system  8  may also include multiple mainframe computers, such as mainframe computer  18 , which may be preferably coupled to LAN  10  by means of communications link  22 . The mainframe computer  18  may also be coupled to a storage device  20  which may serve as remote storage for LAN  10 . Similarly, LAN  10  may be coupled via communications link  24  through a sub-system control unit/communications controller  26  and communications link  34  to a gateway server  28 . The gateway server  28  is preferably an IWS which serves to link LAN  32  to LAN  10 . 
     With respect to LAN  32  and LAN  10 , a plurality of documents or resource objects maybe stored within storage device  20  and controlled by mainframe computer  18 , as resource manager or library service for the resource objects thus stored. Of course, those skilled in the art will appreciate that mainframe computer  18  may be located a great geographic distance from LAN  10  and similarly, LAN  10  may be located a substantial distance from LAN  32 . For example, LAN  32  may be located in California while LAN  10  may be located within North Carolina and mainframe computer  18  may be located in New York. 
     Software program code which employs the present invention is typically stored in the memory of a storage device  14  of a stand alone workstation or LAN server from which a developer may access the code for distribution purposes, the software program code may be embodied on any of a variety of known media for use with a data processing system such as a diskette or CD-ROM or may be distributed to users from a memory of one computer system over a network of some type to other computer systems for use by users of such other systems. Such techniques and methods for embodying software code on media and/or distributing software code are well-known and will not be further discussed herein. 
     The present invention utilizes a well known color mixing model such as RGB (for red, green, blue). Each color has 256 shades starting with the darkest shade as value 0 and progressing to the brightest shade as value 255. To obtain the desired color, RGB mixes the appropriate shade value of each RGB. By selecting one of the colors and all of its associated shades while deselecting all of the other shades of the other two colors, the present invention can present an image by starting with all image pixels that fall into a pattern comprising various shade values for that selected color. For example, the present invention is described as selecting only blue and deselecting red and green. Thus, a pattern such as, for example, a progressively larger circle, can have a center made up of blue values of 0 (darkest) and blue values gradually increasing outwardly to 255. Then, by mapping an image to the pattern and assigning each image pixel a blue value corresponding to where it appears on the pattern, the image may be made to appear gradually by painting the lowest value to the highest value. 
     It is also to be understood that the present invention contemplates a wide variety of the use of color in the RGB scale or any other color scale, such as CYMK (cyan, yellow, magenta and black). For example, the red scale and the green scale can be used to determine other effects on the pixels. Red can be used to determine opacity while green can be used to transform (i.e., move such as rotate) the pixel. Thus, in conjunction with the blue to determine when each image pixel is displayed, the red component of the pattern could determine how intense the image pixel is painted and the green could cause the image to rotate. 
     It is to be understood that the color pattern chosen for demonstration purposes herein could be easily rearranged in any fashion. For example, blue could be used for opacity and red for when a pixel may appear. Also, going from a 0 value of a color to the 255 value is arbitrary and could just as easily go from 255 to 0 or some other variation thereof. Likewise, any other functionality can be assigned to any of the colors. For example, red could be used to represent an arc tangent function, green could be used to represent a sine function and blue could be used to represent a cosine function. 
     In order to illustrate the present invention, an example is herein described using the RGB color scale with blue values from 0 to 255 while green and red have no values. A star image is to appear gradually from the right to the left (a wipe left effect) using a circle pattern (darkest blue, value 0, in the center of the circle and gradually brighter blue concentrically outward, see FIGS. 4 and 6) file. 
     Referring to FIG. 2, a graphical representation of a special effects editor such as, for example, AppletAuthor Composer from IBM Corp., for use with the present invention is generally identified by the reference numeral  100 . Upon opening the editor  100 , a Palette  102 , an empty (although already filled in by subsequent steps, this panel is initially empty) image panel  104  and a Details panel  106  are surfaced on a work area  108  thereof. 
     A user then selects an image part  110  from the palette  102  and a drags-and-drops the part  110  (the image part  110  at this point comprises a border with handles only) therefrom onto the image panel  104 . The user must now set properties for the image and the desired effect by selecting the Properties tab  112  in the Details panel  106 . By selecting “picture”  114 , a listing of files that comprise available images will pop-up (not shown). The user has decided, for example, to display a star  116  (as shown in the image panel  104 ) with the desired special effect. By choosing the appropriate file from the pop-up, the file name (for example, D:\appauthor\samples\star.gif) appears in the field  118  adjacent to picture  114 . It is to be understood that the listing of available images may be created by any appropriate method such as scanning a photograph, transfer from an image editor, etc. 
     The user then selects “transition”  120  from the Details panel  106  which surfaces a pattern file dialogue (not shown). The user selects the desired special effect pattern from the dialogue which is entered into field  122  (for example, D:\appauthor\transitions\smallcircle.gif). Again, for example, the user has selected a wipe-in starting from the right based on a small circle (see FIG.  4 ), which will be subsequently described in greater detail. It is to be understood that the pattern file may be created using any image editor such as, for example, Photoshop from Adobe. The remaining properties may then be selected or, alternatively, the default values may be accepted. The user must then return to the Palette  102  and select a control, for example, Start Transition push-button  124 , which is dragged-and-dropped into the image panel  104 . 
     Referring next to FIG. 3, the user has selected the “Connections” tab  125  in the Details panel  106 . The appropriate options are entered to make the connections, for example, when the push-button  124  is clicked, start the transition for Imagel (i.e., start the wipe-in of the star from the right to the left). A “Run the Applet” button  130  is then selected, and the Java class (or only other programming language code) is compiled. 
     A preview window  200  (see FIGS. 5A,  5 B,  5 C and  5 D) then appears in order to allow the user to preview the selected effect on the selected image. For example, FIG. 5A shows the right-most portion of the star beginning to appear. FIG. 5B-5D show progressively more of the star image from the right to the left until the entire image appears. Thus, the star appears as a wipe-in from the right to the left. 
     Referring to FIG. 6, a more complex example utilizing the present invention is shown. The present invention will allow the user to select the number and type of effects on any image down to and including the selection of how and when each individual image pixel will appear. In FIG. 6, the user has selected three progressively smaller circle patterns for the effect on whatever image is being used. Following the above example, this would mean that the portion of the image coincident with the centers of each circle would appear simultaneously and the image would gradually appear outward from the three centers until the whole image is visible. 
     Referring to FIGS. 7 and 8, a high level flowchart illustrates the present invention. Referring first to FIG. 7, the pattern (i.e., the effect) is first loaded at block  700 . At block  702 , the image to be transitioned is loaded. Then, at block  704 , the present invention begins to obtain pixel information from the image starting with the upper left hand pixel (moving left to right and top to bottom with each iteration). 
     The pixel image is then mapped at block  706  to the corresponding position in the pattern file and a “Blue” value is obtained therefor. The position, blue value and image pixel information is stored in internal structure at block  708 . It is then determined at decision block  710  whether or not there are more image pixels. 
     If the response to decision block  710  is yes, the present invention returns to block  704  for the next pixel. If the response to decision block  710  is no, the present invention proceeds to A in FIG.  8 . All image pixels corresponding to a specific blue value (for example, starting with 0 (the darkest) and moving up to 255 (the brightest)) are displayed at block  800 . It is determined at decision block  802  whether or not there are more blue values in the pattern. If the response to decision block  802  is yes, the next higher blue value is displayed at block  800 . If the response to decision block  802  is no, the present invention is finished at block  804 . 
     It is important to understand that the image and the pattern do not need to be dimensionally identical. Mapping as used herein includes the use of relative position in the pattern file and the image file to determine the value of the effect on the image pixel. Standard algebraic ratios are used along with standard rounding techniques to determine the image pixel position in the pattern file which then determines the amount of the effect applied to the pixel based on the color value at that pattern file position. For example, a 100×100 pixel image is being mapped to a 10×10 pixel pattern file. The center pixel of the image ( 50 , 50 ) is mapped to position  5 , 5  in the pattern file (50/100=x/10; x=5). 
     Although the present invention has been described with respect to a specific preferred embodiment thereof, various changes and modifications may be suggested to one skilled in the art and it is intended that the present invention encompass such changes and modifications as fall within the scope of the appended claims.