Skip to content
New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Jump to bottom

Reorder attributes in doc to match order in header #1494

Merged
merged 1 commit into from
Jul 26, 2023
Merged

Reorder attributes in doc to match order in header #1494

Changes from all commits
Commits
Show all changes
1 commit
Select commit
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
267 changes: 133 additions & 134 deletions docs/StandardOptionalAttributes.rst
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -10,135 +10,10 @@ Standard Optional Attributes

By default, OpenEXR files have the following attributes:

**chromaticities**
For RGB images, specifies the CIE (x,y) chromaticities of the
primaries and the white point.

**whiteLuminance**
For RGB images, defines the luminance, in Nits (candelas per square
meter) of the RGB value (1.0, 1.0, 1.0).

If the chromaticities and the whiteLuminance of an RGB image are
known, then it is possible to convert the image's pixels from RGB to
CIE XYZ tristimulus values.

**adoptedNeutral**
Specifies the CIE (x,y) coordinates that should be considered
neutral during color rendering. Pixels in the image file whose
(x,y) coordinates match the adoptedNeutral value should be mapped to
neutral values on the display.


**renderingTransform**, lookModTransform
Specify the names of the CTL functions that implements the intended
color rendering and look modification transforms for this image.

**xDensity**
Horizontal output density, in pixels per inch. The image's vertical
output density is xDensity * pixelAspectRatio.

**owner**
Name of the owner of the image.

**comments**
Additional image information in human-readable form, for example a
verbal description of the image.

**capDate**
The date when the image was created or captured, in local time, and
formatted as ``YYYY:MM:DD hh:mm:ss``, where ``YYYY`` is the year (4
digits, e.g. 2003), ``MM`` is the month (2 digits, 01, 02, ... 12),
``DD`` is the day of the month (2 digits, 01, 02, ... 31), hh is the
hour (2 digits, 00, 01, ... 23), mm is the minute, and ss is the
second (2 digits, 00, 01, ... 59).

**utcOffset**
Universal Coordinated Time (UTC), in seconds: UTC == local time +
utcOffset

**longitude**, **latitude**, **altitude**
For images of real objects, the location where the image was
recorded. Longitude and latitude are in degrees east of Greenwich
and north of the equator. Altitude is in meters above sea level.
For example, Kathmandu, Nepal is at longitude 85.317, latitude
27.717, altitude 1305.

**focus**
The camera's focus distance, in meters.

**exposure**
Exposure time, in seconds.

**aperture**
The camera's lens aperture, in f-stops (focal length of the lens
divided by the diameter of the iris opening).

**isoSpeed**
The ISO speed of the film or image sensor that was used to record
the image.

**envmap**
If this attribute is present, the image represents an environment
map. The attribute's value defines how 3D directions are mapped to
2D pixel locations.

**keyCode**
For motion picture film frames. Identifies film manufacturer, film
type, film roll and frame position within the roll.

**timeCode**
Time and control code

**wrapmodes**
Determines how texture map images are extrapolated. If an OpenEXR
file is used as a texture map for 3D rendering, texture coordinates
(0.0, 0.0) and (1.0, 1.0) correspond to the upper left and lower
right corners of the data window. If the image is mapped onto a
surface with texture coordinates outside the zero-to-one range, then
the image must be extrapolated. This attribute tells the renderer
how to do this extrapolation. The attribute contains either a pair
of comma-separated keywords, to specify separate extrapolation modes
for the horizontal and vertical directions; or a single keyword, to
specify extrapolation in both directions (e.g. "clamp,periodic" or
"clamp"). Extra white space surrounding the keywords is allowed,
but should be ignored by the renderer ("clamp, black " is equivalent
to "clamp,black"). The keywords listed below are predefined; some
renderers may support additional extrapolation modes:

**black**
pixels outside the zero-to-one range are black

**clamp**
texture coordinates less than 0.0 and greater than 1.0 are clamped
to 0.0 and 1.0 respectively.

**periodic**
the texture image repeats periodically

**mirror**
the texture image repeats periodically, but every other instance
is mirrored

**framesPerSecond**
Defines the nominal playback frame rate for image sequences, in
frames per second. Every image in a sequence should have a
framesPerSecond attribute, and the attribute value should be the
same for all images in the sequence. If an image sequence has no
framesPerSecond attribute, playback software should assume that the
frame rate for the sequence is 24 frames per second.

In order to allow exact representation of NTSC frame and field
rates, framesPerSecond is stored as a rational number. A rational
number is a pair of integers, n and d, that represents the value
n/d.

**multiView**
Defines the view names for multi-view image files. A multi-view
image contains two or more views of the same scene, as seen from
different viewpoints, for example a left-eye and a right-eye view
for stereo displays. The multiView attribute lists the names of the
views in an image, and a naming convention identifies the channels
that belong to each view.
**originalDataWindow**
If application software crops an image, then it should save the data
window of the original, un-cropped image in the originalDataWindow
attribute.

**worldToCamera**
For images generated by 3D computer graphics rendering, a matrix
Expand Down Expand Up @@ -272,6 +147,135 @@ By default, OpenEXR files have the following attributes:
physical photosites; these are edge cases in every sense
of the phrase.

**xDensity**
Horizontal output density, in pixels per inch. The image's vertical
output density is xDensity * pixelAspectRatio.

**longitude**, **latitude**, **altitude**
For images of real objects, the location where the image was
recorded. Longitude and latitude are in degrees east of Greenwich
and north of the equator. Altitude is in meters above sea level.
For example, Kathmandu, Nepal is at longitude 85.317, latitude
27.717, altitude 1305.

**isoSpeed**
The ISO speed of the film or image sensor that was used to record
the image.

**expTime**
Exposure time, in seconds.

**aperture**
The camera's lens aperture, in f-stops (focal length of the lens
divided by the diameter of the iris opening).

**focus**
The camera's focus distance, in meters.

**owner**
Name of the owner of the image.

**comments**
Additional image information in human-readable form, for example a
verbal description of the image.

**capDate**
The date when the image was created or captured, in local time, and
formatted as ``YYYY:MM:DD hh:mm:ss``, where ``YYYY`` is the year (4
digits, e.g. 2003), ``MM`` is the month (2 digits, 01, 02, ... 12),
``DD`` is the day of the month (2 digits, 01, 02, ... 31), hh is the
hour (2 digits, 00, 01, ... 23), mm is the minute, and ss is the
second (2 digits, 00, 01, ... 59).

**utcOffset**
Universal Coordinated Time (UTC), in seconds: UTC == local time +
utcOffset

**keyCode**
For motion picture film frames. Identifies film manufacturer, film
type, film roll and frame position within the roll.

**timeCode**
Time and control code

**framesPerSecond**
Defines the nominal playback frame rate for image sequences, in
frames per second. Every image in a sequence should have a
framesPerSecond attribute, and the attribute value should be the
same for all images in the sequence. If an image sequence has no
framesPerSecond attribute, playback software should assume that the
frame rate for the sequence is 24 frames per second.

In order to allow exact representation of NTSC frame and field
rates, framesPerSecond is stored as a rational number. A rational
number is a pair of integers, n and d, that represents the value
n/d.

**chromaticities**
For RGB images, specifies the CIE (x,y) chromaticities of the
primaries and the white point.

**whiteLuminance**
For RGB images, defines the luminance, in Nits (candelas per square
meter) of the RGB value (1.0, 1.0, 1.0).

If the chromaticities and the whiteLuminance of an RGB image are
known, then it is possible to convert the image's pixels from RGB to
CIE XYZ tristimulus values.

**adoptedNeutral**
Specifies the CIE (x,y) coordinates that should be considered
neutral during color rendering. Pixels in the image file whose
(x,y) coordinates match the adoptedNeutral value should be mapped to
neutral values on the display.

**renderingTransform**, lookModTransform
Specify the names of the CTL functions that implements the intended
color rendering and look modification transforms for this image.

**envmap**
If this attribute is present, the image represents an environment
map. The attribute's value defines how 3D directions are mapped to
2D pixel locations.

**wrapmodes**
Determines how texture map images are extrapolated. If an OpenEXR
file is used as a texture map for 3D rendering, texture coordinates
(0.0, 0.0) and (1.0, 1.0) correspond to the upper left and lower
right corners of the data window. If the image is mapped onto a
surface with texture coordinates outside the zero-to-one range, then
the image must be extrapolated. This attribute tells the renderer
how to do this extrapolation. The attribute contains either a pair
of comma-separated keywords, to specify separate extrapolation modes
for the horizontal and vertical directions; or a single keyword, to
specify extrapolation in both directions (e.g. "clamp,periodic" or
"clamp"). Extra white space surrounding the keywords is allowed,
but should be ignored by the renderer ("clamp, black " is equivalent
to "clamp,black"). The keywords listed below are predefined; some
renderers may support additional extrapolation modes:

**black**
pixels outside the zero-to-one range are black

**clamp**
texture coordinates less than 0.0 and greater than 1.0 are clamped
to 0.0 and 1.0 respectively.

**periodic**
the texture image repeats periodically

**mirror**
the texture image repeats periodically, but every other instance
is mirrored

**multiView**
Defines the view names for multi-view image files. A multi-view
image contains two or more views of the same scene, as seen from
different viewpoints, for example a left-eye and a right-eye view
for stereo displays. The multiView attribute lists the names of the
views in an image, and a naming convention identifies the channels
that belong to each view.

**deepImageState**
Specifies whether the pixels in a deep image are sorted and
non-overlapping.
Expand All @@ -285,11 +289,6 @@ By default, OpenEXR files have the following attributes:
as the software will not crash or lock up if any pixels are
inconsistent with the deepImageState attribute.

**originalDataWindow**
If application software crops an image, then it should save the data
window of the original, un-cropped image in the originalDataWindow
attribute.

**dwaCompressionLevel**
Sets the quality level for images compressed with the DWAA or DWAB
method.
Expand Down