* builds the RGB color string from the color. * reads the red, green; and blue values for. * constructs an ANNOTATE dataset by

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1 IMPORTING X WINDOW SYSTEMTM RASTER IMAGES INTO SAS/GRAPHR SOFIWARE OUTPUT Bernadette Johnson Wendy D. Johnson Pharmaceutical Product Development, Inc. SAS Institute Inc. Introduction Under the UNIXR operating system, a workstation monitor bitmap image can be captured and stored as a binary file. Most X Window systems capture and replay images using the UNIX commands xwd and xwud, respectively. Many systems provide a library of images created from digitized photographs. These images, as well as user-generated images, can now be imported into SAS/GRAPH software to create powerful presentation graphs. This paper describes a macro used to import X Window raster images into SAS/GRAPH software and redisplay them using the Annotate facility. The %XWDTOSAS Macro After selecting or creating a raster image, the macro XWDTOSAS, is used to process the image. The macro %XWDTOSAS: * reads the image header information and determines the file header size, number of colors in the image, and image width and height * reads the red, green; and blue values for each color in tfie COlor map * builds the RGB color string from the color map values * constructs an ANNOTATE dataset by reading each image pixel value * produces a graph using PROC GANNO. The %XWDTOSAS macro program and output examples are located in the Appendix. Image file structure The binary image file contains a fixed header section, separate red, green, and blue color map information, and the pixel values. Reading the file header information The image files are read as an unformatted stream of bytes (RECFM = N) with each byte read as an IBM mainframe positive integer binary value (informat = S370FPIB).For example: data _null_; infile xwd recfm=n; input (headsize ncolors ". p_height byteline.. ) (S370FPIB4.) From the header, the file header size (headsize), number of colors (ncolors), image width (byteline) and image height (p height) are stored in macro variables to help-process the file. call symput(/headsize',compress(headsize»; Building the RGB Color String The color map has individual values for red, green, and blue. The number of colors is read from the file header and stored in the macro variable NCOLORS. The values are combined to form an RGB color specification string with the following format: "CX"llred(hex2 )llgreen(hex2 )llblue(hex2.). array rgb{o:ncolors} $8 coloro-color&ncolors; *read color map values and create custom colors for SAS/GRAPH software. do i=1 to ncolors; input pix S370fpib4. r 9 b xs s370fpib2.; rgb{pi x}= IICXII II put(r,$hex2.) II put(g,$hex2.) II put(b,$hex2.); 543

2 Creating the Annotate Dataset The annotate facility requires a special dataset where the observations correspond to graphic commands. The dataset produced by this macro contains a series of move and draw commands, color assignments, and the x and y coordinates needed to reproduce the original image. Refer to the SAS/GRAPH Software: Reference for further information on the annotate dataset structure. Each pixel value is a pointer or index into the color map. The number of bytes necessary to construct one line (P WIDTH) are read. The individual bytes are processed to determine the pixel color. A line segment is drawn until the color changes or until the end of the line is found. If the color changes, the current line is stopped, the color is reset, and a new segment begins. When the end of line is encountered, the pointer is reset to the beginning of the next line. do y=&height to 1 by ~1j * move the graph pointer to the left of the screen; stop; x~1; function='move' ; output anna; *read a image file tine; input (tine{*}) (s370fpib1.); *process while the x coordinate has not reached the end of the line; do while ( x <= &width); * if this is the first pixel of the line, reset last color to the current color; if (x=1) then last_elr = line{x}; *if the color changes or the end of the line is reached, fetch the color string, draw the previous line and output to annotate dataset; if (tine{x) NE last_elr) or (x~&w;dth) then do; color=rgb{last_clr}; function='draw'j output anna; * reset the last color holder to the current color value; last_clr=line{x}; end; *increment the x coordinate; x + 1; end; * do while x loopi end; *do while Y loop; Producing the SAS/GRAPH software output The GOPTIONS "gunit = cells vpos=&height hpos = &width" divides the vertical and horizontal plotting areas into cell positions equal to the width and height of the original image. The GANNO Procedure reads the annotate dataset and creates the graph. goptlons gunit=cells vpos=&height hpos=&width; proc ganno anno=anno; quit; Requirements In order to import raster images, you need: * the SAS System Version 6 (Base SAS software and SAS/GRAPB software) * an X Window System window raster image * an output device (terminal, printer, camera, etc.). Conclusion SAS/GRAPH output can be enhanced with imported raster images to produce more aesthetic graphs that capture your audience and focus their attention. Questions and/or comments may be directed to: Bernadette Johnson Pharmaceutical Product Development, Inc Meridith Drive Durham, NC Ph: (919) FAX: (919) Wendy Johnson SAS Institute Inc. SAS Campus Drive Cary, NC Ph: (919) FAX: (919) SASjGRAPH is a registered trademark of SAS Institute Inc. in the USA and other countries. R indicates USA registration. UNIX is a registered trademark of AT&T. The X Window System is a trademark of the Massachusetts Institute of Technology. The images used for this paper were obtained from unknown sources on various public domain billboards. Other brand and product names are registered trademarks or trademarks of their respective companies. 544

3 Appendix: The macro XYDTOSAS. To run the macro, call %xwdtosas(filename) where filename is the name of the xwd binary file. %macro xwdtosas(fname); /******************************************************/ /* */ /* NAME: xwd_to_sas */ /* TITLE: Convert XYD raster file to SAS/GRAPH output */ /* PROOUCT: Base SAS Software, SAS/GRAPH Software */ /* SYSTEM: SAS under UNIX, Version 6 */ /* DESC: This program takes a run-byte encoded raster */ /* file and reads the header information, reads and' */ /* stores the color map info, and creates an annotate*/ /* dataset that can be used with PROC GANNO to create*/ /* a SAS graph. The data set is structured so that */ /* move s are only done to decrement line positions. */ /* Else the draw is done for the line segment until *1 /* the color changes or end of the line is reached. */ /******************************************************/ * define the raster filename to fileref xwd; filename xwd li&fname"; * Read the raster file header to determine the width, height, number of colors and size of the header(in bytes). Store this info in macro variables. After the header is read, stop processing; data _null_; infile xwd recfm=n; input (headsize fi le_ver p_format p_depth p_width p_height xoffset byte_ord b_unit b_bi tord byad b_pixel by tel ine visclass r _mask g_mask b_mask bts_rgb cmap_ent ncolors w_width w_height (s370fpib4.) ( w_x w_y (s370fib4. ( w_bdrwdt (s370fpib4.) call symput('headsize',trim(left(headsize»); call symput( 'ncolors',trim( Left(ncol"ors-1»)i call symput('width' call symput('height',trim( left(bytel ine» );,trim(left(p_height»)i stop; ********************************************************,... data anno ( rep 1 ace=yes bufsize=8 keep=cotor x y xsys ysys zsys function size); retain size 16 xsys ysys zsys '4 function,, tast_elr -99; Length function $ 8; * read in image file; infile xwd recf~n ; *read in header information again. place in junk array NOT to be processed.; array junk {*} j1-j&headsize; input (j1-j&headsize) (s370fpib1.); *set up the array for the pixel values; array line {1:&width}; *set up the array format for the color map info; array rgb {O:&ncoLors} $ 8 coloro-color&ncolors; *the color map info has the map values in a stream form, with all the red, followed by all the blue, and all of the green so create temp arrays that; * will be joined later into array rgb array limits are set to 0 to 255 to correspond to the hex values 00 to FF; * construct the RGB color string and put into RGB array; * pix and xs are variables that are NOT used in macro. ; do i=o to &ncolors; input pix s370fpib4. r 9 b xs s370fpib2.; rgb{i}="cx" II p.jt(r,$hex2.) II put(g,$hex2.) II put(b,$hex2.); end; ********************************************; *process every line in the image file; doy=&height to 1 by '1; * move the graph pointer to the left of the screen; x=1; 545.

4 stop; function='move'i output anno; *read a image fi Ie 1 fne; input (line{*}) (s370fpib1.); *process while the x coordinate has not reached the end of the line; do while ( x <= &width); * if this is the first pixel of the line, reset last color to the current color; if (x=1) then last_clr = line{x}; *if the color changes or the end of the line is reached, fetch the color string, draw the previous line and output to annotate dataset; if (line{x) NE last_clr) or (x=&width) then do; color=rgb{last_clr}i function='draw'; output anna; * reset the last color holder to the current color value; last_clr=line{x}; end; *increment the x coordinatej x + 1; end; * do while x loop; end; *do while Y loop; *******************************************************; *set the graphics environment to the proper proportions to represent the graph; goptions gunit=cells vpos=&height hpos=&width nopromptj * use PRoe GANNO to display the graph; proc ganna anno=anno; quit; 'YdIlendj * end of macro; *******************************************************; 546

5 U,S, Dollars in Circulation In Millions of Dollars Totaiin Circulation $4,000. r , 01.j>. -.J $3,000 $2, $1,OC~J f'.. i '10""0 ""J 1960 ' YEf\R Source:The World Almanac 1988

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