PICT

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|extensions={{ext|pict}}, {{ext|pct}}, {{ext|pic}}
 
|extensions={{ext|pict}}, {{ext|pct}}, {{ext|pic}}
 
|pronom={{PRONOM|fmt/341}}, {{PRONOM|x-fmt/80}}
 
|pronom={{PRONOM|fmt/341}}, {{PRONOM|x-fmt/80}}
 +
|wikidata={{wikidata|Q2044200}}
 
|released=1984
 
|released=1984
 
}}
 
}}
'''PICT''', or '''QuickDraw/PICT''', is a graphics file format native to Macintosh computers. It is associated with the QuickDraw API.
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'''PICT''', or '''QuickDraw/PICT''', is a graphics format native to Macintosh computers. It is associated with the QuickDraw API.
  
 
Though it is a vector format, it is often used as if it were a raster format. Many files contain just a single bitmap image.
 
Though it is a vector format, it is often used as if it were a raster format. Many files contain just a single bitmap image.
  
 
PICT format is complicated and quirky. Although plenty of documentation about it exists, there does not appear to be any single source that provides a reasonably clear and complete specification.
 
PICT format is complicated and quirky. Although plenty of documentation about it exists, there does not appear to be any single source that provides a reasonably clear and complete specification.
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 +
== Format details ==
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When PICT is used as a standalone file format, the file usually starts with an unused 512-byte header, usually with all bytes set to 0. When PICT is embedded as a resource inside some other format, this header is usually not present.
  
 
== Identification ==
 
== Identification ==
A version 1 PICT file has (hex) bytes {{magic|11 01}} at offset 522, and ends with {{magic|ff}}.
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A version 1 PICT file has (hex) bytes {{magic|11 01}} at offset 522 (or 10 if there is no header), and should end with {{magic|ff}}.
  
A version 2 PICT file has bytes {{magic|00 11 02 ff 0c 00}} at offset 522, and ends with {{magic|00 ff}}.
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A version 2 PICT file has bytes {{magic|00 11 02 ff 0c 00}} at offset 522 (or 10 if there is no header), and should end with {{magic|00 ff}}.
  
 
== Application data ==
 
== Application data ==
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* 100 is an Application Comment (see below).
 
* 100 is an Application Comment (see below).
 
* 220 is used for [[ICC profile]] data.
 
* 220 is used for [[ICC profile]] data.
* 498 appears to be related to [[PSD|Photoshop]], though it might also be used for other things.
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* 498 appears to be related to [[Photoshop]], though it might also be used for other things.
  
 
The "kind" does little to identify the application, or prevent collisions. A better way is to use kind 100, which has a standard way to include a 4-byte application signature.
 
The "kind" does little to identify the application, or prevent collisions. A better way is to use kind 100, which has a standard way to include a 4-byte application signature.
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* Many bitmap images are compressed using [[PackBits]].
 
* Many bitmap images are compressed using [[PackBits]].
 
* Opcodes 0x8200 and 0x8201 use a format based on [[QuickTime]] or [[QTIF]]. This, in turn, is often used as a wrapper for an image in [[JPEG]] format.
 
* Opcodes 0x8200 and 0x8201 use a format based on [[QuickTime]] or [[QTIF]]. This, in turn, is often used as a wrapper for an image in [[JPEG]] format.
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* [[Macintosh resource file]] - Often contains "PICT" resources in this format
 
* PICT is used for graphics stored within [[Keynote]] documents.
 
* PICT is used for graphics stored within [[Keynote]] documents.
 
* [[Encapsulated PostScript]]
 
* [[Encapsulated PostScript]]
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== Resources ==
 
== Resources ==
 
* {{EGFF|macpict|Macintosh PICT File Format Summary}}, from the [[Encyclopedia of Graphics File Formats]]
 
* {{EGFF|macpict|Macintosh PICT File Format Summary}}, from the [[Encyclopedia of Graphics File Formats]]
* [http://www.sno.phy.queensu.ca/~phil/exiftool/TagNames/PICT.html ExifTool: PICT Tags]
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* [https://www.sno.phy.queensu.ca/~phil/exiftool/TagNames/PICT.html ExifTool: PICT Tags]
 
* [[Wikipedia:PICT|Wikipedia article]]
 
* [[Wikipedia:PICT|Wikipedia article]]
  
 
[[Category:Macintosh]]
 
[[Category:Macintosh]]

Revision as of 21:47, 10 September 2019

File Format
Name PICT
Ontology
Extension(s) .pict, .pct, .pic
MIME Type(s) image/x-pict, image/pict
PRONOM fmt/341, x-fmt/80
Wikidata ID Q2044200
Released 1984

PICT, or QuickDraw/PICT, is a graphics format native to Macintosh computers. It is associated with the QuickDraw API.

Though it is a vector format, it is often used as if it were a raster format. Many files contain just a single bitmap image.

PICT format is complicated and quirky. Although plenty of documentation about it exists, there does not appear to be any single source that provides a reasonably clear and complete specification.

Contents

Format details

When PICT is used as a standalone file format, the file usually starts with an unused 512-byte header, usually with all bytes set to 0. When PICT is embedded as a resource inside some other format, this header is usually not present.

Identification

A version 1 PICT file has (hex) bytes 11 01 at offset 522 (or 10 if there is no header), and should end with ff.

A version 2 PICT file has bytes 00 11 02 ff 0c 00 at offset 522 (or 10 if there is no header), and should end with 00 ff.

Application data

Custom application data can be stored in PICT files by using the "LongComment" opcode. Each comment has an integer that identifies its "kind".

Notable comment kinds:

  • 100 is an Application Comment (see below).
  • 220 is used for ICC profile data.
  • 498 appears to be related to Photoshop, though it might also be used for other things.

The "kind" does little to identify the application, or prevent collisions. A better way is to use kind 100, which has a standard way to include a 4-byte application signature.

Related formats

Specifications

Software

Sample files

Resources

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