PrintPartner

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(Created page with "{{FormatInfo |formattype=electronic |subcat=Graphics |extensions={{ext|gph}} |released=1990 }} '''PrintPartner''' is a desktop publishing program for MS-DOS. It was developed ...")
 
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'''PrintPartner''' is a desktop publishing program for MS-DOS. It was developed by Acropolis Software, and released mainly as freeware. It has a native '''.GPH''' graphics format.
 
'''PrintPartner''' is a desktop publishing program for MS-DOS. It was developed by Acropolis Software, and released mainly as freeware. It has a native '''.GPH''' graphics format.
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== GPH format details ==
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''This information is based on reverse engineering and guesswork. It may not be correct.''
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File:
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{| class="wikitable"
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!Field name !! Type !! Details
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|-
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|ID/comments || char[] || ASCII text
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|-
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|ID terminator || byte || = 0x1a
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|-
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|image_sequence || Image[] || See below
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|}
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Image:
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{| class="wikitable"
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!Field name !! Type !! Details
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|-
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|name_len || byte || Expected to be from 1 to 20.
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|-
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|name || char[20] || ASCII text, padded with spaces
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|-
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|cmpr_type || byte || 1=uncompressed, 2="RLE8", 3="RLE4"
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|-
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|height || byte || Image height in pixels
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|-
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|rowbytes || byte || width = rowbytes×8. The width is always a multiple of 8 pixels. Unused columns are expected to have all-white pixels.
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|-
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|image_data || byte[] || The size of this element must be calculated, in order to locate the next image. The way to do that depends on cmpr_type (see below).
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|}
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=== Uncompressed format ===
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1 bit per pixel, white is 0. There is no header, or row padding. The size of the image_data element is height×rowbytes bytes.
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=== RLE8 format ===
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This is a byte-oriented compression scheme. It has a 2-byte header containing the number of compressed bytes. Add 2 to this value to get the size in bytes of the image_data element. After decompression, the data is in the "uncompressed" format described above.
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{| class="wikitable"
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! Code byte (N) !! Instructions
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|-
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|N ≤ 127 || Emit the next N bytes literally.
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|-
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|N ≥ 128 || Emit the next byte N−128 times.
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|}
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=== RLE4 format ===
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This is a pixel-oriented compression scheme. There is a 2-byte header containing the number of 4-bit "nibbles". Each nibble encodes a run of white or black pixels. To calculate the size of the image_data element, divide the number of nibbles by 2, rounding up, and add 2.
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Start with an all-white canvas.
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{| class="wikitable"
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! Code nibble (N) !! Instructions
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|-
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|N ≤ 7 || Leave the next N pixels white.
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|-
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|N ≥ 8 || Make the next N−8 pixels black.
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|}
  
 
== Identification ==
 
== Identification ==

Revision as of 16:14, 3 November 2017

File Format
Name PrintPartner
Ontology
Extension(s) .gph
Released 1990

PrintPartner is a desktop publishing program for MS-DOS. It was developed by Acropolis Software, and released mainly as freeware. It has a native .GPH graphics format.

Contents

GPH format details

This information is based on reverse engineering and guesswork. It may not be correct.

File:

Field name Type Details
ID/comments char[] ASCII text
ID terminator byte = 0x1a
image_sequence Image[] See below

Image:

Field name Type Details
name_len byte Expected to be from 1 to 20.
name char[20] ASCII text, padded with spaces
cmpr_type byte 1=uncompressed, 2="RLE8", 3="RLE4"
height byte Image height in pixels
rowbytes byte width = rowbytes×8. The width is always a multiple of 8 pixels. Unused columns are expected to have all-white pixels.
image_data byte[] The size of this element must be calculated, in order to locate the next image. The way to do that depends on cmpr_type (see below).

Uncompressed format

1 bit per pixel, white is 0. There is no header, or row padding. The size of the image_data element is height×rowbytes bytes.

RLE8 format

This is a byte-oriented compression scheme. It has a 2-byte header containing the number of compressed bytes. Add 2 to this value to get the size in bytes of the image_data element. After decompression, the data is in the "uncompressed" format described above.

Code byte (N) Instructions
N ≤ 127 Emit the next N bytes literally.
N ≥ 128 Emit the next byte N−128 times.

RLE4 format

This is a pixel-oriented compression scheme. There is a 2-byte header containing the number of 4-bit "nibbles". Each nibble encodes a run of white or black pixels. To calculate the size of the image_data element, divide the number of nibbles by 2, rounding up, and add 2.

Start with an all-white canvas.

Code nibble (N) Instructions
N ≤ 7 Leave the next N pixels white.
N ≥ 8 Make the next N−8 pixels black.

Identification

GPH files apparently start with some ASCII text that begins "PrintPartner Art".

Software

Sample files

Retrieved from "http://fileformats.archiveteam.org/index.php?title=PrintPartner&oldid=29108"
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