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- GrabScrn - Screen Grabber Ver 1.1
- ---------------------------------
-
- BECAUSE GRABSCRN IS LICENSED FREE OF CHARGE, I PROVIDE ABSOLUTELY NO
- WARRANTY, TO THE EXTENT PERMITTED BY APPLICABLE STATE LAW. EXCEPT WHEN
- OTHERWISE STATED IN WRITING, I GERSHON ELBER PROVIDE GRABSCRN PROGRAM
- "AS IS" WITHOUT WARRANTY OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING,
- BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- A PARTICULAR PURPOSE. THE ENTIRE RISK AS TO THE QUALITY AND PERFORMANCE OF THE
- PROGRAM IS WITH YOU. SHOULD THE GRABSCRN PROGRAM PROVE DEFECTIVE, YOU ASSUME
- THE COST OF ALL NECESSARY SERVICING, REPAIR OR CORRECTION.
-
- IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW WILL GERSHON ELBER,
- BE LIABLE TO YOU FOR DAMAGES, INCLUDING ANY LOST PROFITS, LOST MONIES,
- OR OTHER SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF THE
- USE OR INABILITY TO USE (INCLUDING BUT NOT LIMITED TO LOSS OF DATA OR A
- FAILURE OF THE PROGRAM TO OPERATE WITH PROGRAMS NOT DISTRIBUTED BY GERSHON
- ELBER) THE PROGRAM, EVEN IF YOU HAVE BEEN ADVISED OF THE POSSIBILITY OF
- SUCH DAMAGES, OR FOR ANY CLAIM BY ANY OTHER PARTY.
-
-
- Introduction
- -------------
- This program dumps the graphics screen as a linear non compressed data. An
- auxiliary program is provided to convert this raw data into an GIF image.
- GrabScrn is a TSR program. First time it is executed it leaves a resident
- portion that is activated by the hot key ALT-F10. Each time the hot key is
- pressed three new files named 'GrScrxxx.yyy' are created where xxx is an index
- increased by one each time up to 999 and yyy is one of "bat", "cmp" and "raw".
-
-
- Usage
- -----
- Usage: GrabScrn [-d] Device
- where
- Device may be one of:
- 1. HERC - 720 by 350 1 bit per pixel (2 colors).
- 2. CGAL - 320 by 200 2 bits per pixel (4 colors).
- 3. CGAH - 640 by 200 1 bits per pixel (2 colors).
- 4. EGALO - 640 by 200, default 4 bits per pixel (16 colors).
- 5. EGAMED - 640 by 350, default 4 bits per pixel (16 colors).
- 6. VGALO - 640 by 200, default 4 bits per pixel (16 colors).
- 7. VGAMED - 640 by 350, default 4 bits per pixel (16 colors).
- 8. VGAHI - 640 by 480, default 4 bits per pixel (16 colors).
- 9. SVGA - 800 by 600, default 4 bits per pixel (16 colors).
- 10. UVGA - 1024 by 768, default 4 bits per pixel (16 colors).
- d is optional bits per pixel digit. Default is specified above.
-
- Once GrabScrn is installed, device may be modified by simply reexecuting
- GrabScrn with a new device name. Note device name must be in UPPER CASE.
-
- The three files saved each time the hot key is been pressed are:
- GrScxxx.raw - the screen information in raw data format - one screen raw
- after another with one byte per pixel. xxx is image number up to 999.
- GrScrxxx.cmp - The color map. This is a regular text file with one entry per
- line of the form "Index Red Green Blue".
- GrScrxxx.bat - Batch file, that when executed converts the raw and color
- map files above into a gif image. The raw and cmp files are been
- deleted once done.
- A tool named Raw2Gif from the giflib11.zip gif tool kit
- (see PD:<MSDOS.GIF> on simtel20.arpa) is used for that purpose and
- is provided here for completeness purposes. See Raw2Gif.doc for more.
-
- Two examples of color map files are provided. one for ega default color
- palette (colormap.ega) and one for hercules (colormap.her).
-
-
- General notes
- -------------
- The raw files are always saved as one byte per pixel. This was made mainly
- from simplicity reasons although it may require lots of disk space. All CGA
- EGA and VGA modes uses the bios int 0x10, service 0x0c to retrieve the
- screen buffer information and service 0x1015 to retrieve the palette.
- This ensures compatibility on the expense of time. The following
- table hints on the space/time requirement for single screen dump:
-
- Device | File size | time (80286 12Mhz) | Comments
- -------+------------+--------------------+----------------
- HERC | 252000 | 9 Sec. |
- EGA | 224000 | 49 Sec. | 640 x 350 mode (EGAMED)
- VGA | 307200 | 67 Sec. | 640 x 480 mode (VGAHI)
- SVGA | 480000 | 97 Sec. | 800 x 600 mode (SVGA)
-
- The Hercules mode queries bits information directly (no BIOS support for it)
- and the speedup is obvious...
-
- Because of the complexity envolved in detecting different modes and devices
- a safer approach has been taken and it is the user responsibility to
- "tell" this program what mode the device will be in once the hot key is
- been pressed.
-
- Although this program was designed to minimize machine dependability,
- it uses fairly low level calls and it may not work on your system.
- If it does not, but you fixed it to work for your system, please send me
- your changes so I can incorporate them in. If you can not - please do not
- send me any specific machine problem kind of mail unless you are willing to
- buy me a system like yours - I am not going to buy one...
-
- The GrabScrn.c module can be easily modified to support other display
- devices. If you did that, please send me your changes so I can incorporate
- them into this program officially.
-
- Gershon Elber
- Email: gershon@cs.utah.edu
-
-