PCX图形文件格式说明:he following is culled from a USENET posting by [email protected] Reference ManualIncluding Information For: Publisher's Paintbrush~ PC Paintbrush~ Plus PC Paintbrush FRIEZE Graphics~ZSoft Corporation 450 Franklin Rd. Suite 100 Marietta, GA 30067 (404) 428-0008Copyright 1988 ZSoft Corporation Table of ContentsIntroduction Image File (.PCX) Format Decoding the .PCX File Format Palette Information Description PC Paintbrush Bitmap Font Format Sample "C" Routines FRIEZE Technical Information Pre-7.00 FRIEZE Specifications Pre-7.00 FRIEZE Function Calls Pre-7.00 FRIEZE Error Codes 7.00 and later FRIEZE Specifications 7.00 and later FRIEZE Function Calls 7.00 and later FRIEZE Error Codes The .PCX Programmer's ToolkitIntroductionThis booklet was designed to aid developers and users in understanding the technical aspects of the .PCX file format and the use of FRIEZE. Any comments, questions or suggestions about this booklet should be sent to: ZSoft Corporation Technical Support Department ATTN: Technical Reference Manual 450 Franklin Rd. Suite 100 Marietta, GA 30067 USA
IMAGE FILE (.PCX) FORMATThe information in this section will be useful if you want to write a program to read or write PCX files (images). If you want to write a special case program for one particular image format you should be able to produce something that runs twice as fast as "Load from..." in PC Paintbrush. Image files used by PC Paintbrush product family and FRIEZE (those with a .PCX extension) begin with a 128 byte header. Usually you can ignore this header, since your images will all have the same resolution. If you want to process different resolutions or colors, you will need to interpret the header correctly. The remainder of the image file consists of encoded graphic data. The encoding method is a simple byte oriented run-length technique. We reserve the right to change this method to improve efficiency. When more than one color plane is stored in the file, each line of the image is stored by color plane (generally ordered red, green, blue, intensity), as shown below.Scan line 0: RRR... GGG... BBB... III... Scan line 1: RRR... GGG... BBB... III... (etc.)The encoding method is: FOR each byte, X, read from the file IF the top two bits of X are 1's then count = 6 lowest bits of X data = next byte following X ELSE count = 1 data = XSince the overhead this technique requires is, on average, 25% of the non-repeating data and is at least offset whenever bytes are repeated, the file storage savings are usually considerable. The format of the file header is shown below.ZSoft .PCX FILE HEADER FORMATByte Item Size Description/Comments0 Manufacturer 1 Constant Flag 10 = ZSoft .PCX 1 Version 1 Version information: 0 = Version 2.5 2 = Version 2.8 w/palette information 3 = Version 2.8 w/o palette information 5 = Version 3.0 2 Encoding 1 1 = .PCX run length encoding 3 Bits per pixel 1 Number of bits/pixel per plane 4 Window 8 Picture Dimensions (Xmin, Ymin) - (Xmax - Ymax) in pixels, inclusive 12 HRes 2 Horizontal Resolution of creating device 14 VRes 2 Vertical Resolution of creating device 16 Colormap 48 Color palette setting, see text 64 Reserved 1 65 NPlanes 1 Number of color planes 66 Bytes per Line 2 Number of bytes per scan line per color plane (always even for .PCX files) 68 Palette Info 2 How to interpret palette - 1 = color/BW, 2 = grayscale 70 Filler 58 blank to fill out 128 byte headerAll variables of size 2 are integers.
Decoding .PCX FilesFirst, find the pixel dimensions of the image by calculating [XSIZE = Xmax - Xmin + 1] and [YSIZE = Ymax - Ymin + 1]. Then calculate how many bytes are required to hold one complete uncompressed scan line: TotalBytes = NPlanes * BytesPerLine Note that since there are always an integral number of bytes, there will probably be unused data at the end of each scan line. TotalBytes shows how much storage must be available to decode each scan line, including any blank area on the right side of the image. You can now begin decoding the first scan line - read the first byte of data from the file. If the top two bits are set, the remaining six bits in the byte show how many times to duplicate the next byte in the file. If the top bits are not set, the first byte is the data itself, with a count of one. Continue decoding the rest of the line. Keep a running subtotal of how many bytes are moved and duplicated into the output buffer. When the subtotal equals TotalBytes, the scan line is complete. There will always be a decoding break at the end of each scan line. But there will not be a decoding break at the end of each plane within each scan line. When the scan line is completed, there may be extra blank data at the end of each plane within the scan line. Use the XSIZE and YSIM values to find where the valid image data is. If the data is multi-plane BytesPerLine shows where each plane ends within the scan line. Continue decoding the remainder of the scan lines. There may be extra scan lines at the bottom of the image, to round to 8 or 16 scan lines. Palette Information DescriptionEGA/VGA 16 Color Palette InformationThe palette information is stored in one of two different formats. In standard RGB format (IBM EGA, IBM VGA) the data is stored as 16 triples. Each triple is a 3 byte quantity of Red, Green, Blue values. The values can range from 0-255 so some interpre tation into the base card format is necessary. On an IBM EGA, for example, there are 4 possible levels of RGB for each color. Since 256/4 = 64, the following is a list of the settings and levels:Setting Level 0-63 0 64-127 1 128-192 2 193-254 3 VGA 256 Color Palette InformationZSoft has recently added the capability to store palettes containing more than 16 colors in the .PCX image file. The 256 color palette is formatted and treated the same as the 16 color palette, except that it is substantially longer. The palette (number of colors x 3 bytes in length) is appended to the end of the .PCX file, and is preceded by a 12 decimal. To determine the VGA BIOS palette you need only divide the values read in the palette by 4. To access a 256 color palette: First, check the version number in the header, if it contains a 5 there is a palette. Second, read to the end of the file and count back 769 bytes. The value you find should be a 12 decimal, showing the presence of a 256 color palette. CGA Color Palette Information For a standard IBM CGA board, the palette settings are a bit more complex. Only the first byte of the triple is used. The first triple has a valid first byte which represents the background color. To find the background, take the (unsigned) byte value and divide by 16. This will give a result between 0-15, hence the background color. The second triple has a valid first byte, which represents the foreground palette. PC Paintbrush supports 8 possible CGA palettes, so when the foreground setting i ded between 0 and 255, there are 8 ranges of numbers and the divisor is 32. CGA Color MapHeader Byte #16 Background color is determined in the upper four bits. Header Byte #19 Only upper 3 bits are used, lower 5 bits are ignored. The first three bits that are used are ordered C, P, I. These bits are interpreted as follows:c: color burst enable - 0 = color; 1 = monochrome p: palette - 0 = yellow; 1 = white i: intensity - 0 = dim; 1 = bright PC Paintbrush Bitmap Character FormatThe bitmap character fonts are stored in a particularly simple format. The format of these characters is as follows:Header (2 bytes) font width db 0a0h + character width (in dots) font height db character height (in dots) Character Widths (256 bytes) char widths db 256 dup(each char's width +1) Character Images (remainder of the file)The characters are stored in ASCII order and as many as 256 may be provided. Each character is left justified in the character block, all characters take up the same number of bytes. Bytes are organized as N strings, where each string is one scan line of the character. See figure 2. For example, each character in a 5x7 font requires 7 bytes. A 9x14 font uses 28 bytes per character (stored two bytes per scan line in 14 sets of 2 byte packets). Custom fonts may be any size up to the current maximum of 10K bytes allowed for a font fil e.
特别是这里：一个例子：Sample "C" RoutinesThe following is a simple set of C subroutines to read data from a .PCX file./* This procedure reads one encoded block from the image file and stores a count and data byte. Result: 0 = valid data stored EOF = out of data in file */encget(pbyt, pcnt, fid) int *pbyt; /* where to place data */ int *pcnt; /* where to place count */ FILE *fid; /* image file handle */ { int i; *pcnt = 1; /* safety play */ if(EOF == (i = getc(fid))) return(EOF); if(0xc0 == (0xc0 & i)) { *pcnt = 0x3f&i; if(EOF == (i=getc(fid))) return(EOF); } *pbyt = i; return(0); } /* Here's a program fragment using encget. This reads an entire file and stores it in a (large) buffer, pointed to by the variable "bufr". "fp" is the file pointer for the image */while (EOF != encget(&chr, &cnt, fp)) for (i = 0; i ~ *bufr++ = chr; The following is a set of C subroutines to write data to a .PCX file. /* This subroutine encodes one scanline and writes it to a file */encLine(inBuff, inLen, fp) unsigned char *inBuff; /* pointer to scanline data */ int inLen; /* length of raw scanline in bytes */ FILE *fp; /* file to be written to */ { /* returns number of bytes written into outBuff, 0 if failed */ unsigned char this, last; int srcIndex, i; register int total; register unsigned char runCount; /* max single runlength is 63 */ total = 0; last = *(inBuff); runCount = 1;for (srcIndex = 1; srcIndex inLen; srcIndex++) { this = *(++inBuff); if (this == last) { runCount++; /* it encodes */ if (runCount == 63) { if (!(i=encput(last, runCount, fp))) return(0); total += i; runCount = 0; } } else { /* this != last */ if (runCount) { if (!(i=encput(last, runCount, fp))) return(0); total += i; } last = this; runCount = 1; } } /* endloop */ if (runCount) { /* finish up */ if (!(i=encput(last, runCount, fp))) return(0); return(total + i); } return(total); }/* subroutine for writing an encoded byte pair (or single byte if it doesn't encode) to a file */ encput(byt, cnt, fid) /* returns count of bytes written, 0 if err */ unsigned char byt, cnt; FILE *fid; { if(cnt) { if( (cnt==1) && (0xc0 != (0xc0&byt)) ) { if(EOF == putc((int)byt, fid)) return(0); /* disk write error (probably full) */ return(1); } else { if(EOF == putc((int)0xC0 | cnt, fid)) return(0); /* disk write error */ if(EOF == putc((int)byt, fid)) return(0); /* disk write error */ return(2); } } return(0); }FRIEZE Technical Information FRIEZE InformationFRIEZE is a memory resident utility that allows you to capture and save graphic images from other programs. You can then bring these images into PC Paintbrush for editing and enhancement. FRIEZE was rewritten for use in PC Paintbrush Plus, and so the technical information about FRIEZE has changed dramatically. To easily provide technical information for all versions of FRIEZE, we have split this section of the manual into two parts, one about PRE-7.00 versions of FRIEZE, and one about the current versions (7.00 or higher). FRIEZE 7.10 and later can be removed from memory (this can return you almost 85K of DOS RAM, depending on your configuration). To do this, you can choose to release FRIEZE from memory in the PCINSTAL menu, or at any time by changing directories to your P C PAINTBRUSH product directory and typing the word "FRIEZE."
Pre-7.00 FRIEZE Specifications FRIEZE Print Option SettingsFRIEZE can easily adapt to incomplete printer cables (missing IBM specified status lines) and will drive either serial or parallel devices. Note that FRIEZE always uses the standard BIOS calls, so a non-handshaking device will time out, but can be told to ignore such things as paper out. The FRIEZE command syntax is: FRIEZE Xnaarr Where: X = either Parallel or Serial n = port number aa = a two digit hexadecimal code for which return bits cause an abort rr = a two digit hexadecimal code for which return bits cause a retry Examples: FRIEZE P1 - use the default settings of Parallel output, port number 1, abort mask of 28h, and retry mask of 01h FRIEZE P2 - use printer port #2 FRIEZE S1 - use serial port #1, and Xon/Xoff handshaking FRIEZE P10028 - use printer port #1, abort mask of 00 (nothing is read as an error) and retry mask of 28h Interpreting the codes: On return from the parallel printer call, the bit interpretations are: 80h - busy signal (0=busy) 40h - acknowledge 20h - out of paper 10h - selected 08h - I/O error 04h - unused 02h - unused 01h - time out FRIEZE Function CallsFRIEZE is operated using software interrupt number 10h (the video interrupt call). To make a FRIEZE function call, load 75 (decimal) into the AH register, the function call number into the CL register and then, either load AL with the function argument or load ES and BX with a segment and offset which point to the function argument the n do an int 10h. FRIEZE will return a result code number in AX--zero means success, other values show error conditions. All other registers are unchanged.No. Definition Arguments 0 Print Window AL = mode: 0 - character, 1 - normal, 2 - sideways 1 Read Window ES:BX - string (filename to read from) 2 Write Window ES:BX - string (filename to write to) 3 Print Width AL = width in 1/4 inches 4 Print Height AL = height in 1/4 inches 5 Reserved 6 Set Left Margin AL = printout margin in 1/4 inches 7 Set Window Size ES:BX - 4 element word vector of window settings: Xmin, Ymin, Xmax, Ymax 8 Reserved 9 Set Patterns ES:BX - 16 element vector of byte values containing the screen-to-printer color correspondence 10 Get Patterns ES:BX - room for 16 bytes as above 11 Set Mode AL = mode number (See SETMODE command) 12 Reserved 13 Reserved 14 Reserved 15 Get Window ES:BX - room for 4 words of the current window settings 16 Set Print Options ES:BX - character string of printer options. Same format as for the FRIEZE command. 17 Initialize ES:BX - 3 word array containing data from PC Paintbrush Disk 1 file CARDS.DAT (Hres, Vres, optional code number) All character strings are ended by a zero byte (ASCIIZ format). FRIEZE Error CodesWhen FRIEZE is called using interrupt 10 hex, it will return an error code in the AX register. A value of zero shows that there was no error. A nonzero result means there was an error. These error codes are explained below.0 No Error 1 Printout was stopped by user with the ESC key 2 Reserved 3 File read error 4 File write error or printer error 5 File not found 6 Invalid Header or can't create file (not a picture or wrong screen mode) 7 File close error 8 Disk error - usually drive door open 9 Not used 10 Invalid command - CL was set to call a nonexistent FRIEZE function 11 Not used 12 Not used 7.00 and Later FRIEZEThe newer versions of FRIEZE have a different number of parameters on its command line. The new FRIEZE command line format is:FRIEZE {PD} {Xnaarr} {flags} {video} {hres} {vres} {vnum}Where:{PD} Printer driver filename (without the .PDV extension) {Xnaarr} X=S for Serial Printer X=P for Parallel Printer n = port number aa = Two digit hex code for which return bits cause an abort rr = Two digit hex code for which return bits cause a retry {flags} Four digit hex code First Digit controls Length Flag Second Digit controls Width Flag Third Digit controls Mode Flag Fourth Digit controls BIOS Flag NOTE: The length, width and mode flags are printer driver specific. See PRINTERS.DAT on disk 1 for correct use. In general width flag of 1 means wide carriage, and 0 means standard width. Length flag of 0 and mode flag of 0 means use standard printer driver settings. {video} Video driver combination, where the leading digit signifies the high level video driver and the rest signifies the low level video driver Example = 1EGA - uses DRIVE1 and EGA.DEV {hres} Horizontal resolution of the desired graphics mode {vres} Vertical resolution of the desired graphics mode {vnum} Hardware specific parameter (usually number of color planes) Note: The last four parameters can be obtained from the CARDS.DAT file, on Disk 1 of your PC Paintbrush diskettes. Parallel printer return codes: 80h - Busy Signal (0=busy) 40h - Acknowledge 20h - Out of paper 10h - Selected 08h - I/O error 04h - Unused 02h - Unused 01h - Time out
FRIEZE Function CallsFRIEZE is operated using software interrupt number 10h (the video interrupt call). To make a FRIEZE function call, load 75 (decimal) into the AH register, the function number into the CL register and then, either load AL with the function argument or load ES and BX with a segment and offset which point to the function argument then do an int 10h. FRIEZE will return a result code number in AX--zero means success, other values show error conditions. All other registers are unchanged.No. Definition Arguments 0 Reserved 1 Load Window ES:BX - string (filename to read from) 2 Save Window ES:BX - string (filename to write to) 3 Reserved 4 Reserved 6 Reserved 7 Set Window Size ES:BX - 4 element word vector of window settings: Xmin, Ymin, Xmax, Ymax 8 Reserved 9 Set Patterns ES:BX - 16 element vector of byte values containing the screen-to-printer color correspondence 10 Get Patterns ES:BX - room for 16 bytes as above 11 Set Mode AL = mode number (See SETMODE command) 12 Reserved 13 Reserved 14 Reserved 15 Get Window ES:BX - room for 4 words of the current window settings 16 Set Print Options ES:BX - character string of printer options. Same format as for the FRIEZE command. 17 Reserved 18 Reserved 19 Reserved 20 Get FRIEZE Version. AH gets the whole number portion and AL gets the decimal portion of the version number. If AH=0, it can be assumed that it is a pre-7.00 version of FRIEZE. 21 Set Parameters ES:BX points to an 8 word table (16 bytes) of parameter settings: TopMargin, LeftMargin, HSize,VSize, Quality/Draft Mode, PrintHres, PrintVres, Reserved. Margins and sizes are specified in hundredths of inches. Q/D mode parameter values: 0 - draft print mode 1 - quality print mode 2 - use Hres, Vres for output resolution. Print resolutions are specified in DPI. Any parameter which should be left unchanged may be filled with a (-1) (0FFFF hex). The reserved setting should be filled with a (-1). 22 Get Parameters ES:BX points to an 8 word table (16 bytes) where parameter settings are held. 23 Get Printer Res ES:BX points to a 12 word table (24 bytes) where printer resolution pairs (6 pairs) are held. NOTE: All character strings are ended by a zero byte (ASCIIZ format). FRIEZE Error CodesWhen FRIEZE is called using interrupt 10 hex, it will return an error code in the AX register. A value of zero shows that there was no error. A nonzero result means there was an error. These error codes are explained below.0 No Error 1 Printout was stopped by user with the ESC key 2 Reserved 3 File read error 4 File write error 5 File not found 6 Invalid Header - not an image, wrong screen mode 7 File close error 8 Disk error - usually drive door open 9 Printer error - printer is off or out of paper 10 Invalid command - CL was set to call a nonexistent FRIEZE function 11 Can't create file - write protect tab or disk is full 12 Wrong video mode - FRIEZE cannot capture text screens.
The PCX Programmer's ToolkitThe .MDBO/PCX Programmer's Toolkit.MDNM/, by Genus Microprogramming, allows developers to create applications with the ability to display, save, capture, and manipulate PCX format images. Because it supports the most common display adapters and compilers , the toolkit can be used in a wide variety of areas. Besides the library interfaces, many utility programs are provided for displaying and capturing screens, creating windows, inspecting image headers and locating coordinates. Over 35 routines for displaying and saving images from buffers and files, setting palettes, accessing image headers, and more. Written in Assembler for maximum display speed Fast enough for animation Image library manager saves disk space and makes portability easy (group multiple PCX images in a single library file) Display images within database applicationsDisplays Supported: All Modes of the Hercules, CGA, EGA, and VGA graphics adapters.Compilers Supported: Linkable libraries are provided for Microsoft C, Turbo C, QuickC, Lattice C, QuickBasic, Turbo Pascal, and Clipper. Quick libraries are provided for the Microsoft integrated compilers, and a unit is provided for Turbo Pascal. Small, Medium, and Large model libraries are included for compilers that support multiple memory models.Software Supported: Paint packages such as ZSoft's PC Paintbrush and Microsoft Paintbrush are directly compatible. Desktop Publishing packages supported include Xerox Ventura Publisher and Aldus PC PageMaker.What the Toolkit Requires: An IBM PC/XT/AT or 100% compatible, 120disk drive, an IBM CGA/EGA/VGA, or Hercules adapter (or 100% compatible), and DOS 2.0 or above. Only $89.95!!!Order direct from: ZSoft Corporation 450 Franklin Rd., Suite 100 Marietta, GA. 30057 (404) 428-0008Microsoft, Microsoft C, QuickC, QuickBasic, and Microsoft Paintbrush are trades of Microsoft Corporation. Turbo C, Turbo Basic, and Turbo Pascal are trades of Borland International. Clipper is a trade of Nantucket Software. Lattice C is a trade of Lattice Corporation. Hercules is a trade of Hercules Corporation. Other software packages are trades of their respective companies.
Publisher's Paintbrush~
PC Paintbrush~ Plus
PC Paintbrush
FRIEZE Graphics~ZSoft Corporation
450 Franklin Rd. Suite 100
Marietta, GA 30067
(404) 428-0008Copyright 1988 ZSoft Corporation
Table of ContentsIntroduction
Image File (.PCX) Format
Decoding the .PCX File Format
Palette Information Description
PC Paintbrush Bitmap Font Format
Sample "C" Routines
FRIEZE Technical Information
Pre-7.00 FRIEZE Specifications
Pre-7.00 FRIEZE Function Calls
Pre-7.00 FRIEZE Error Codes
7.00 and later FRIEZE Specifications
7.00 and later FRIEZE Function Calls
7.00 and later FRIEZE Error Codes
The .PCX Programmer's ToolkitIntroductionThis booklet was designed to aid developers and users in understanding
the technical aspects of the .PCX file format and the use of FRIEZE.
Any comments, questions or suggestions about this booklet should be
sent to: ZSoft Corporation Technical Support Department
ATTN: Technical Reference Manual
450 Franklin Rd. Suite 100
Marietta, GA 30067
USA
program to read or write PCX files (images). If you want to write a
special case program for one particular image format you should be
able to produce something that runs twice as fast as "Load from..." in
PC Paintbrush. Image files used by PC Paintbrush product family and
FRIEZE (those with a .PCX extension) begin with a 128 byte header.
Usually you can ignore this header, since your images will all have
the same resolution. If you want to process different resolutions or
colors, you will need to interpret the header correctly. The
remainder of the image file consists of encoded graphic data. The
encoding method is a simple byte oriented run-length technique. We
reserve the right to change this method to improve efficiency. When
more than one color plane is stored in the file, each line of the
image is stored by color plane (generally ordered red, green, blue,
intensity), as shown below.Scan line 0: RRR...
GGG...
BBB...
III...
Scan line 1: RRR...
GGG...
BBB...
III...
(etc.)The encoding method is: FOR each byte, X, read from the file
IF the top two bits of X are 1's then
count = 6 lowest bits of X
data = next byte following X
ELSE
count = 1
data = XSince the overhead this technique requires is, on average, 25% of the
non-repeating data and is at least offset whenever bytes are repeated,
the file storage savings are usually considerable. The format of the
file header is shown below.ZSoft .PCX FILE HEADER FORMATByte Item Size Description/Comments0 Manufacturer 1 Constant Flag 10 = ZSoft .PCX
1 Version 1 Version information:
0 = Version 2.5
2 = Version 2.8 w/palette information
3 = Version 2.8 w/o palette information
5 = Version 3.0
2 Encoding 1 1 = .PCX run length encoding
3 Bits per pixel 1 Number of bits/pixel per plane
4 Window 8 Picture Dimensions
(Xmin, Ymin) - (Xmax - Ymax)
in pixels, inclusive
12 HRes 2 Horizontal Resolution of creating device
14 VRes 2 Vertical Resolution of creating device
16 Colormap 48 Color palette setting, see text
64 Reserved 1
65 NPlanes 1 Number of color planes
66 Bytes per Line 2 Number of bytes per scan line per
color plane (always even for .PCX files)
68 Palette Info 2 How to interpret palette - 1 = color/BW,
2 = grayscale
70 Filler 58 blank to fill out 128 byte headerAll variables of size 2 are integers.
Xmax - Xmin + 1] and [YSIZE = Ymax - Ymin + 1]. Then calculate how
many bytes are required to hold one complete uncompressed scan line:
TotalBytes = NPlanes * BytesPerLine Note that since there are always
an integral number of bytes, there will probably be unused data at the
end of each scan line. TotalBytes shows how much storage must be
available to decode each scan line, including any blank area on the
right side of the image. You can now begin decoding the first scan
line - read the first byte of data from the file. If the top two bits
are set, the remaining six bits in the byte show how many times to
duplicate the next byte in the file. If the top bits are not set, the
first byte is the data itself, with a count of one. Continue decoding
the rest of the line. Keep a running subtotal of how many bytes are
moved and duplicated into the output buffer. When the subtotal equals
TotalBytes, the scan line is complete. There will always be a
decoding break at the end of each scan line. But there will not be a
decoding break at the end of each plane within each scan line. When
the scan line is completed, there may be extra blank data at the end
of each plane within the scan line. Use the XSIZE and YSIM values to
find where the valid image data is. If the data is multi-plane
BytesPerLine shows where each plane ends within the scan line.
Continue decoding the remainder of the scan lines. There may be extra
scan lines at the bottom of the image, to round to 8 or 16 scan lines.
Palette Information DescriptionEGA/VGA 16 Color Palette InformationThe palette information is stored in one of two different formats. In
standard RGB format (IBM EGA, IBM VGA) the data is stored as 16
triples. Each triple is a 3 byte quantity of Red, Green, Blue values.
The values can range from 0-255 so some interpre tation into the base
card format is necessary. On an IBM EGA, for example, there are 4
possible levels of RGB for each color. Since 256/4 = 64, the
following is a list of the settings and levels:Setting Level
0-63 0
64-127 1
128-192 2
193-254 3
VGA 256 Color Palette InformationZSoft has recently added the capability to store palettes containing
more than 16 colors in the .PCX image file. The 256 color palette is
formatted and treated the same as the 16 color palette, except that it
is substantially longer. The palette (number of colors x 3 bytes in
length) is appended to the end of the .PCX file, and is preceded by a
12 decimal. To determine the VGA BIOS palette you need only divide
the values read in the palette by 4. To access a 256 color palette:
First, check the version number in the header, if it contains a 5
there is a palette. Second, read to the end of the file and count
back 769 bytes. The value you find should be a 12 decimal, showing
the presence of a 256 color palette. CGA Color Palette Information
For a standard IBM CGA board, the palette settings are a bit more
complex. Only the first byte of the triple is used. The first triple
has a valid first byte which represents the background color. To find
the background, take the (unsigned) byte value and divide by 16. This
will give a result between 0-15, hence the background color. The
second triple has a valid first byte, which represents the foreground
palette. PC Paintbrush supports 8 possible CGA palettes, so when the
foreground setting i ded between 0 and 255, there are 8 ranges of
numbers and the divisor is 32.
CGA Color MapHeader Byte #16
Background color is determined in the upper four bits.
Header Byte #19
Only upper 3 bits are used, lower 5 bits are ignored. The first three
bits that are used are ordered C, P, I. These bits are interpreted as
follows:c: color burst enable - 0 = color; 1 = monochrome
p: palette - 0 = yellow; 1 = white
i: intensity - 0 = dim; 1 = bright
PC Paintbrush Bitmap Character FormatThe bitmap character fonts are stored in a particularly simple format.
The format of these characters is as follows:Header (2 bytes)
font width db 0a0h + character width (in dots)
font height db character height (in dots)
Character Widths (256 bytes)
char widths db 256 dup(each char's width +1)
Character Images
(remainder of the file)The characters are stored in ASCII order and as many as 256 may be
provided. Each character is left justified in the character block,
all characters take up the same number of bytes. Bytes are organized
as N strings, where each string is one scan line of the character.
See figure 2. For example, each character in a 5x7 font requires 7
bytes. A 9x14 font uses 28 bytes per character (stored two bytes per
scan line in 14 sets of 2 byte packets). Custom fonts may be any size
up to the current maximum of 10K bytes allowed for a font fil e.
stores a count and data byte. Result:
0 = valid data stored
EOF = out of data in file */encget(pbyt, pcnt, fid)
int *pbyt; /* where to place data */
int *pcnt; /* where to place count */
FILE *fid; /* image file handle */
{
int i;
*pcnt = 1; /* safety play */
if(EOF == (i = getc(fid))) return(EOF);
if(0xc0 == (0xc0 & i)) {
*pcnt = 0x3f&i;
if(EOF == (i=getc(fid)))
return(EOF);
}
*pbyt = i;
return(0);
}
/* Here's a program fragment using encget. This reads an entire file
and stores it in a (large) buffer, pointed to by the variable "bufr".
"fp" is the file pointer for the image */while (EOF != encget(&chr, &cnt, fp))
for (i = 0; i ~ *bufr++ = chr;
The following is a set of C subroutines to write data to a .PCX file. /* This subroutine encodes one scanline and writes it to a file */encLine(inBuff, inLen, fp)
unsigned char *inBuff; /* pointer to scanline data */
int inLen; /* length of raw scanline in bytes */
FILE *fp; /* file to be written to */
{ /* returns number of bytes written into outBuff, 0 if failed */
unsigned char this, last;
int srcIndex, i;
register int total;
register unsigned char runCount; /* max single runlength is 63 */
total = 0;
last = *(inBuff); runCount = 1;for (srcIndex = 1; srcIndex inLen; srcIndex++) {
this = *(++inBuff);
if (this == last) {
runCount++; /* it encodes */
if (runCount == 63) {
if (!(i=encput(last, runCount, fp)))
return(0);
total += i;
runCount = 0;
}
}
else { /* this != last */
if (runCount) {
if (!(i=encput(last, runCount, fp)))
return(0);
total += i;
}
last = this;
runCount = 1;
}
} /* endloop */
if (runCount) { /* finish up */
if (!(i=encput(last, runCount, fp)))
return(0);
return(total + i);
}
return(total);
}/* subroutine for writing an encoded byte pair
(or single byte if it doesn't encode) to a file */
encput(byt, cnt, fid) /* returns count of bytes written, 0 if err */
unsigned char byt, cnt;
FILE *fid;
{
if(cnt) {
if( (cnt==1) && (0xc0 != (0xc0&byt)) ) {
if(EOF == putc((int)byt, fid))
return(0); /* disk write error (probably full) */
return(1);
}
else {
if(EOF == putc((int)0xC0 | cnt, fid))
return(0); /* disk write error */
if(EOF == putc((int)byt, fid))
return(0); /* disk write error */
return(2);
}
}
return(0);
}FRIEZE Technical Information
FRIEZE InformationFRIEZE is a memory resident utility that allows you to capture and
save graphic images from other programs. You can then bring these
images into PC Paintbrush for editing and enhancement. FRIEZE was
rewritten for use in PC Paintbrush Plus, and so the technical
information about FRIEZE has changed dramatically. To easily provide
technical information for all versions of FRIEZE, we have split this
section of the manual into two parts, one about PRE-7.00 versions of
FRIEZE, and one about the current versions (7.00 or higher). FRIEZE
7.10 and later can be removed from memory (this can return you almost
85K of DOS RAM, depending on your configuration). To do this, you can
choose to release FRIEZE from memory in the PCINSTAL menu, or at any
time by changing directories to your P C PAINTBRUSH product directory
and typing the word "FRIEZE."
FRIEZE Print Option SettingsFRIEZE can easily adapt to incomplete printer cables (missing IBM
specified status lines) and will drive either serial or parallel
devices. Note that FRIEZE always uses the standard BIOS calls, so a
non-handshaking device will time out, but can be told to ignore such
things as paper out. The FRIEZE command syntax is: FRIEZE Xnaarr
Where: X = either Parallel or Serial n = port number aa = a two digit
hexadecimal code for which return bits cause an abort rr = a two digit
hexadecimal code for which return bits cause a retry Examples: FRIEZE
P1 - use the default settings of Parallel output, port number 1, abort
mask of 28h, and retry mask of 01h FRIEZE P2 - use printer port #2
FRIEZE S1 - use serial port #1, and Xon/Xoff handshaking FRIEZE P10028
- use printer port #1, abort mask of 00 (nothing is read as an error)
and retry mask of 28h Interpreting the codes: On return from the
parallel printer call, the bit interpretations are: 80h - busy signal
(0=busy) 40h - acknowledge 20h - out of paper 10h - selected 08h - I/O
error 04h - unused 02h - unused 01h - time out
FRIEZE Function CallsFRIEZE is operated using software interrupt number 10h (the video
interrupt call). To make a FRIEZE function call, load 75 (decimal)
into the AH register, the function call number into the CL register
and then, either load AL with the function argument or load ES and BX
with a segment and offset which point to the function argument the n
do an int 10h. FRIEZE will return a result code number in AX--zero
means success, other values show error conditions. All other
registers are unchanged.No. Definition Arguments
0 Print Window AL = mode: 0 - character,
1 - normal, 2 - sideways
1 Read Window ES:BX - string
(filename to read from)
2 Write Window ES:BX - string
(filename to write to)
3 Print Width AL = width in 1/4 inches
4 Print Height AL = height in 1/4 inches
5 Reserved
6 Set Left Margin AL = printout margin in
1/4 inches
7 Set Window Size ES:BX - 4 element word
vector of window settings:
Xmin, Ymin, Xmax, Ymax
8 Reserved
9 Set Patterns ES:BX - 16 element vector
of byte values containing the
screen-to-printer color
correspondence
10 Get Patterns ES:BX - room for 16 bytes as
above
11 Set Mode AL = mode number
(See SETMODE command)
12 Reserved
13 Reserved
14 Reserved
15 Get Window ES:BX - room for 4 words of
the current window settings
16 Set Print Options ES:BX - character string of
printer options. Same format
as for the FRIEZE command.
17 Initialize ES:BX - 3 word array
containing data from
PC Paintbrush Disk 1 file
CARDS.DAT (Hres, Vres,
optional code number)
All character strings are ended by a zero byte (ASCIIZ format).
FRIEZE Error CodesWhen FRIEZE is called using interrupt 10 hex, it will return an error
code in the AX register. A value of zero shows that there was no
error. A nonzero result means there was an error. These error codes
are explained below.0 No Error
1 Printout was stopped by user with the ESC key
2 Reserved
3 File read error
4 File write error or printer error
5 File not found
6 Invalid Header or can't create file
(not a picture or wrong screen mode)
7 File close error
8 Disk error - usually drive door open
9 Not used
10 Invalid command - CL was set to call a nonexistent
FRIEZE function
11 Not used
12 Not used
7.00 and Later FRIEZEThe newer versions of FRIEZE have a different number of parameters on
its command line. The new FRIEZE command line format is:FRIEZE {PD} {Xnaarr} {flags} {video} {hres} {vres} {vnum}Where:{PD} Printer driver filename (without the .PDV extension)
{Xnaarr}
X=S for Serial Printer X=P for Parallel Printer
n = port number
aa = Two digit hex code for which return bits cause
an abort
rr = Two digit hex code for which return bits cause
a retry
{flags} Four digit hex code
First Digit controls Length Flag
Second Digit controls Width Flag
Third Digit controls Mode Flag
Fourth Digit controls BIOS Flag
NOTE: The length, width and mode flags are printer driver specific.
See PRINTERS.DAT on disk 1 for correct use. In
general width flag of 1 means wide carriage, and
0 means standard width. Length flag of 0 and
mode flag of 0 means use standard printer driver
settings.
{video} Video driver combination, where the leading digit
signifies the high level video driver and the rest
signifies the low level video driver
Example = 1EGA - uses DRIVE1 and EGA.DEV
{hres} Horizontal resolution of the desired graphics mode
{vres} Vertical resolution of the desired graphics mode
{vnum} Hardware specific parameter (usually number of color planes)
Note: The last four parameters can be obtained from the CARDS.DAT file, on Disk 1 of your PC Paintbrush diskettes.
Parallel printer return codes:
80h - Busy Signal (0=busy)
40h - Acknowledge
20h - Out of paper
10h - Selected
08h - I/O error
04h - Unused
02h - Unused
01h - Time out
interrupt call). To make a FRIEZE function call, load 75 (decimal)
into the AH register, the function number into the CL register and
then, either load AL with the function argument or load ES and BX with
a segment and offset which point to the function argument then do an
int 10h. FRIEZE will return a result code number in AX--zero means
success, other values show error conditions. All other registers are
unchanged.No. Definition Arguments
0 Reserved
1 Load Window ES:BX - string
(filename to read from)
2 Save Window ES:BX - string
(filename to write to)
3 Reserved
4 Reserved
6 Reserved
7 Set Window Size ES:BX - 4 element word
vector of window settings:
Xmin, Ymin, Xmax, Ymax
8 Reserved
9 Set Patterns ES:BX - 16 element vector
of byte values containing the
screen-to-printer color
correspondence
10 Get Patterns ES:BX - room for 16 bytes as
above
11 Set Mode AL = mode number
(See SETMODE command)
12 Reserved
13 Reserved
14 Reserved
15 Get Window ES:BX - room for 4 words of
the current window settings
16 Set Print Options ES:BX - character string of
printer options. Same format
as for the FRIEZE command.
17 Reserved
18 Reserved
19 Reserved
20 Get FRIEZE Version. AH gets the whole number portion
and AL gets the decimal portion of
the version number. If AH=0, it
can be assumed that it is a
pre-7.00 version of FRIEZE.
21 Set Parameters ES:BX points to an 8 word table
(16 bytes) of parameter settings:
TopMargin, LeftMargin, HSize,VSize,
Quality/Draft Mode, PrintHres,
PrintVres, Reserved.
Margins and sizes are specified in
hundredths of inches.
Q/D mode parameter values:
0 - draft print mode
1 - quality print mode
2 - use Hres, Vres for output
resolution. Print resolutions are
specified in DPI. Any parameter
which should be left unchanged may
be filled with a (-1) (0FFFF hex).
The reserved setting should be filled
with a (-1).
22 Get Parameters ES:BX points to an 8 word table
(16 bytes) where parameter settings
are held.
23 Get Printer Res ES:BX points to a 12 word table
(24 bytes) where printer resolution
pairs (6 pairs) are held.
NOTE: All character strings are ended by a zero byte
(ASCIIZ format).
FRIEZE Error CodesWhen FRIEZE is called using interrupt 10 hex, it will return an error
code in the AX register. A value of zero shows that there was no
error. A nonzero result means there was an error. These error codes
are explained below.0 No Error
1 Printout was stopped by user with the ESC key
2 Reserved
3 File read error
4 File write error
5 File not found
6 Invalid Header - not an image, wrong screen mode
7 File close error
8 Disk error - usually drive door open
9 Printer error - printer is off or out of paper
10 Invalid command - CL was set to call a nonexistent
FRIEZE function
11 Can't create file - write protect tab or disk is full
12 Wrong video mode - FRIEZE cannot capture text screens.
allows developers to create applications with the ability to display,
save, capture, and manipulate PCX format images. Because it supports
the most common display adapters and compilers , the toolkit can be
used in a wide variety of areas. Besides the library interfaces, many
utility programs are provided for displaying and capturing screens,
creating windows, inspecting image headers and locating coordinates.
Over 35 routines for displaying and saving images from buffers and
files, setting palettes, accessing image headers, and more. Written in Assembler for maximum display speed Fast enough for animation Image library manager saves disk space and makes portability easy
(group multiple PCX images in a single library file) Display images within database applicationsDisplays Supported: All Modes of the Hercules, CGA, EGA, and VGA graphics adapters.Compilers Supported: Linkable libraries are provided for Microsoft C, Turbo C, QuickC,
Lattice C, QuickBasic, Turbo Pascal, and Clipper. Quick libraries
are provided for the Microsoft integrated compilers, and a unit is
provided for Turbo Pascal. Small, Medium, and Large model
libraries are included for compilers that support multiple memory
models.Software Supported: Paint packages such as ZSoft's PC Paintbrush and Microsoft
Paintbrush are directly compatible. Desktop Publishing packages
supported include Xerox Ventura Publisher and Aldus PC PageMaker.What the Toolkit Requires: An IBM PC/XT/AT or 100% compatible, 120disk drive, an IBM
CGA/EGA/VGA, or Hercules adapter (or 100% compatible), and DOS 2.0
or above.
Only $89.95!!!Order direct from:
ZSoft Corporation
450 Franklin Rd., Suite 100
Marietta, GA. 30057
(404) 428-0008Microsoft, Microsoft C, QuickC, QuickBasic, and Microsoft Paintbrush
are trades of Microsoft Corporation. Turbo C, Turbo Basic, and
Turbo Pascal are trades of Borland International. Clipper is a
trade of Nantucket Software. Lattice C is a trade of Lattice
Corporation. Hercules is a trade of Hercules Corporation. Other
software packages are trades of their respective companies.