CgBI

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(Created page with "{{FormatInfo |formattype=electronic |subcat=Graphics |extensions={{ext|png}} }} == Overview == '''CgBI''' is the informal name of a PNG-like image file format developed by...")
 
(It is "pngff" and not "ffpng" that supports this format)
 
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|extensions={{ext|png}}
 
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== Overview ==
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'''CgBI''' is the informal name of a [[PNG]]-like image file format developed by Apple. It is also called '''iOS optimized PNG''', and other similar names.
'''CgBI''' is the informal name of a [[PNG]]-like image file format developed by Apple. It may also be called '''iOS optimized PNG'''.
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It is not compatible with PNG. Standard PNG decoders that don't support it will fail gracefully, due to an unknown "critical chunk".
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It is not compatible with PNG. PNG decoders that don't support it should fail completely, due to an unknown "critical chunk".
  
 
== Identification ==
 
== Identification ==
Files begin with the standard 8-byte PNG signature. A private "CgBI" chunk appears before the "IHDR" chunk.
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Files begin with the standard 8-byte [[PNG#Identification|PNG signature]]. A private "CgBI" chunk appears before the "IHDR" chunk. Usually or always, ASCII "{{magic|CgBI}}" appears at offset 12.
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== Software ==
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* [[XnView]]
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* [[Farbfeld Utilities]]: pngff
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* [http://www.jongware.com/pngdefry.html pngdefry] (C)
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* https://github.com/briancollins/PNGNormalizer (C)
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* https://github.com/jongwook/libpng (libpng patch)
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* https://github.com/jakubknejzlik/cgbi-to-png (CoffeeScript)
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* https://github.com/swcai/iphone-png-normalizer (Ruby)
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* [http://howett.net/pincrush/ Pincrush] (encoder)
  
 
== External links ==
 
== External links ==

Latest revision as of 06:52, 16 December 2017

File Format
Name CgBI
Ontology
Extension(s) .png

CgBI is the informal name of a PNG-like image file format developed by Apple. It is also called iOS optimized PNG, and other similar names.

It is not compatible with PNG. PNG decoders that don't support it should fail completely, due to an unknown "critical chunk".

[edit] Identification

Files begin with the standard 8-byte PNG signature. A private "CgBI" chunk appears before the "IHDR" chunk. Usually or always, ASCII "CgBI" appears at offset 12.

[edit] Software

[edit] External links

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