Gri: Image Extractor

Gri Extras 1: Introduction 2: Simple example 3: Fancy example 4: Running Gri 5: Programming Gri 6: General Issues 7: X-Y Plots 8: Contour Plots 9: Image Plots 10: Examples 11: Handling Data 12: Gri Commands 13: Gri Extras 14: Evolution of Gri 15: Installing Gri 16: Gri Bugs 17: System Tools 18: Acknowledgments 19: License 20: Newsgroup 21: Concept Index | ## 13.8: Image extractor When Gri draws an image with ``draw image`', it embeds special comments in the PostScript to allow removal of the data by an extractor program; for details see Image PostScript Output. The extractor program is included along with the source distribution, in the C file called ``gri_extract_image.c`'. After compiling it manually (since there is no Makefile for it), use it as a filter, e.g.
    gri_extract_image < file.ps > file.pgm
The result is an image in the pgm format. ("pgm" stands for portable graymap; see unix manpage on ``pgm`'.) Standard converters are available to convert pgm into most other formats. Note that just the image is output, not the axes or any other part of your drawing. If you want to make your entire page into an image (perhaps for incorporation into a web-page), try using the FSF ``gs`' program. For example, if the PostScript filename is ``foo.ps`', do this:
    $ gs foo.ps
    GS> (pstoppm.ps)run
    GS> (foo) ppm1run
    GS> quit