DataShow GRA

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File Format
Name DataShow GRA
Extension(s) .gra
Released ≤1991

DataShow GRA is a raster graphics format associated with DataShow. DataShow is a presentation and multi-purpose graphics application for DOS, developed by René Michael Plambek.

GRA is a somewhat crude non-compressed format, apparently for a full-screen image.

See also DataShow Sprite.



Here's a way to view a GRA file in DataShow Pro v1.4A (assumes you have a way to run DOS software):

  • Figure out what mode the GRA file uses (see the Identification section of this page).
  • Put the file in the same directory as SHOW.EXE (not required, but simpler).
  • Run SHOW.EXE.
  • At the main menu, press F9 (Setup).
  • Use up/down arrow keys to move the cursor to the "Default Graphics mode" item.
  • Use "+"/"-" keys to select the correct graphics mode, then press F10.
  • At the main menu, press F4 (Draw).
  • At the Draw Center menu, press F9 (Setup).
  • Use up/down arrow keys to move the cursor to the "Graphics type" item.
  • Use "+"/"-" keys to select "GRA" format, then press F10.
  • Press F2 (Files).
  • Use arrow keys to select "Load file", and press Enter.
  • Type the filename, and press Enter. Dismiss the message.
  • At the Draw Center menu, press F4 ("Draw"). The image should be displayed. Press F10 when done.


A GRA file can perhaps be identified using the file size, and the first 3 or 4 bytes of the file. Note that the first two bytes are the image width, minus 1.

[The information in this table was derived from minimal testing, and may be incomplete.]

Mode File size First 4 bytes
CGA - 320x200 16006 3f 01 c7 00
EGA1 - 640x200x16 64006 7f 02 c7 00
EGA2 - 640x350x16 112012 7f 02 c8 00
VGA1 - 640x480x16 153618 7f 02 c8 00
VGA2 - 320x200x256 64006 3f 01 c7 00
SVGA1 - 640x400x256 256024 7f 02 64 00
SVGA2 - 640x480x256 307230 7f 02 64 00
SVGA3 - 800x600x16 240024 1f 03 96 00
SVGA4 - 800x600x256 480048 1f 03 4b 00
SVGA5 - 1024x768x16 393258 ff 03 7d 00
SVGA6 - 1024x768x256 786510 ff 03 3c 00


Sample files

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