PICT

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'''PICT''', or '''QuickDraw/PICT''', is a complex graphics file format used on Macintosh computers. It is associated with the QuickDraw API.
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'''PICT''', or '''QuickDraw/PICT''', is a graphics file 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 complete specification.
  
 
== Identification ==
 
== Identification ==
Version 1 PICT files have (hex) bytes {{magic|11 01}} at offset 522.
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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 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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== Application data ==
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Custom application data can be stored in PICT files by using the "LongComment" opcode. Each comment has an integer that identifies its "kind".
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* [http://www.opennt.net/projects/opennt/repository/revisions/26/entry/trunk/com/ole32/olecnv32/qdcoment.i A file with a list of comment kinds]
  
Version 2 PICT files have bytes {{magic|00 11 02 ff 0c 00}} at file offset 522.
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Notable comment kinds:
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* 100 is an Application Comment (see below).
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* 220 is used for [[ICC profile]] data.
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* 498 appears to be related to [[PSD|Photoshop]], though it might also be used for other things.
  
== Custom data ==
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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.
Custom application data is sometimes stored in PICT files by using (abusing?) the "LongComment" opcode. Comment "kind" 224 is used for [[ICC profile]]s, and kind 498 appears to be related to [[PSD|Photoshop]].
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== Related formats ==
 
== Related formats ==
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* Many bitmap images are compressed using [[PackBits]].
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* 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.
 
* PICT is used for graphics stored within [[Keynote]] documents.
 
* PICT is used for graphics stored within [[Keynote]] documents.
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* [[Encapsulated PostScript]]
  
 
== Specifications ==
 
== Specifications ==
 
* [https://developer.apple.com/legacy/library/documentation/mac/pdf/ImagingWithQuickDraw.pdf Inside Macintosh: Imaging With QuickDraw]
 
* [https://developer.apple.com/legacy/library/documentation/mac/pdf/ImagingWithQuickDraw.pdf Inside Macintosh: Imaging With QuickDraw]
 
* [http://show.docjava.com/posterous/file/2012/07/9614410-DOC01.PDF PICT File Format Notes]
 
* [http://show.docjava.com/posterous/file/2012/07/9614410-DOC01.PDF PICT File Format Notes]
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* [http://web.archive.org/web/20010703041301/http://developer.apple.com/technotes/qd/qd_14.html Macintosh Technical Note QD14 (a.k.a. TN21)]: QuickDraw's Internal Picture Definition - PICT version 1 (from archive.org)
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* [ftp://ftp.oreilly.com/pub/examples/9781565920583/CDROM/GFF/VENDSPEC/MACPIC/PICT.ZIP PICT.ZIP] - Probably a lot of information here, but in inconvenient formats
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* [http://web.archive.org/web/20010422094136/http://developer.apple.com/technotes/qd/qd_06.html Macintosh Technical Note QD06 (a.k.a TN181)]: Every Picture [Comment] Tells Its Story, Don't It? - PICT Application Comments (from archive.org)
 
* [http://research.stowers-institute.org/efg/ScientificSoftware/Utility/TiffTags/ICC-tag.pdf HELIOS ICC profile tagging specifications] - Tells how to embed an ICC profile in a PICT file
 
* [http://research.stowers-institute.org/efg/ScientificSoftware/Utility/TiffTags/ICC-tag.pdf HELIOS ICC profile tagging specifications] - Tells how to embed an ICC profile in a PICT file
  

Revision as of 20:16, 26 October 2015

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

PICT, or QuickDraw/PICT, is a graphics file 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 complete specification.

Contents

Identification

A version 1 PICT file has (hex) bytes 11 01 at offset 522, and ends with ff.

A version 2 PICT file has bytes 00 11 02 ff 0c 00 at offset 522, and ends 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

Personal tools
Namespaces

Variants
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