What is a deep sample in OpenEXR, and how do I tell a point sample from a volume sample and which channels a deep file must have?
An OpenEXR deep pixel holds any number of samples (all channels share the count), each with a depth; Z is required and ZBack optional (copied from Z if absent); Z >= ZBack is a point sample (zero-thickness surface hit) and Z < ZBack a volume sample over [Z, ZBack); each colour or auxiliary channel needs an associated alpha found through its layer and enclosing layers. The library stores the data; the Interpreting Deep Pixels document defines the meaning.
An OpenEXR deep pixel holds any number of samples (all channels share the count), each with a depth; Z is required and ZBack optional (copied from Z if absent); Z >= ZBack is a point sample (zero-thickness surface hit) and Z < ZBack a volume sample over [Z, ZBack); each colour or auxiliary channel needs an associated alpha found through its layer and enclosing layers. The library stores the data; the Interpreting Deep Pixels document defines the meaning.
Curator qualifications: Docs and code read 2026-10-22; nothing composited (code reading, not execution).
Limitations: Docs and code read 2026-10-22; nothing composited (code reading, not execution).
Evidence status: statements located in the cited sources by a correlated desk review (Claude); not executed; not independently reviewed.
Structured fields
{
"citations": [
{
"url": "https://github.com/AcademySoftwareFoundation/openexr/blob/69b2604fc76e370615438bdc8d2cd95b9349c12e/website/InterpretingDeepPixels.rst",
"note": "OpenEXR website/InterpretingDeepPixels.rst at 69b2604f (raw), L24, L139-216"
},
{
"url": "https://github.com/AcademySoftwareFoundation/openexr/blob/69b2604fc76e370615438bdc8d2cd95b9349c12e/website/TechnicalIntroduction.rst",
"note": "OpenEXR website/InterpretingDeepPixels.rst at 69b2604f (raw), L24, L139-216"
}
]
}Evidence claims
- [sourced_fact] An OpenEXR deep pixel holds any number of samples (all channels share the count), each with a depth; Z is required and ZBack optional (copied from Z if absent); Z >= ZBack is a point sample (zero-thickness surface hit) and Z < ZBack a volume sample over [Z, ZBack); each colour or auxiliary channel needs an associated alpha found through its layer and enclosing layers. The library stores the data; the Interpreting Deep Pixels document defines the meaning. · locator: OpenEXR website/InterpretingDeepPixels.rst at 69b2604f (raw), L24, L139-216 source
Rights
| component | license | hosting | redistribution | modification | training | Evidence and notes |
|---|---|---|---|---|---|---|
| documentation | unknown | permitted | permitted | unknown | unknown | Applies to this original summary only, not to the cited sources. |