[libcamera-devel] [PATCH v3 02/13] libcamera: properties: Define pixel array properties

[Jacopo Mondi]

Add definition of pixel array related properties.

Reviewed-by: Niklas Söderlund <niklas.soderlund at ragnatech.se>
Signed-off-by: Jacopo Mondi <jacopo at jmondi.org>
---
 src/libcamera/property_ids.yaml | 155 ++++++++++++++++++++++++++++++++
 1 file changed, 155 insertions(+)

diff --git a/src/libcamera/property_ids.yaml b/src/libcamera/property_ids.yaml
index ce627fa042ba..8f6797723a9d 100644
--- a/src/libcamera/property_ids.yaml
+++ b/src/libcamera/property_ids.yaml
@@ -386,4 +386,159 @@ controls:
                               |                    |
                               |                    |
                               +--------------------+
+
+  - PixelArraySize:
+      type: float
+      size: [2]
+      description: |
+        The physical sizes of the pixel array (width and height), in
+        millimeters.
+
+  - PixelArray:
+      type: int32_t
+      size: [2]
+      description: |
+        The camera sensor pixel array vertical and horizontal sizes, in pixels.
+
+        The property describes a rectangle with its top-left corner in position
+        (0, 0) and width and height described by the first and second values
+        of this property.
+
+        The PixelArray property defines the rectangle that includes all possible
+        rectangles defined by the ActiveAreas property, and describes the full
+        pixel array, including non-active pixels, black level calibration
+        pixels etc.
+
+  - ActiveAreas:
+      type: int32_t
+      size: [4 x n]
+      description: |
+        The camera sensor active pixel area rectangles, represented as
+        rectangles contained in the one described by the PixelArray property.
+
+        This property describes an arbitrary number of overlapping rectangles,
+        representing the active pixel portions of the camera sensor pixel array.
+
+        Each rectangle is defined by its displacement from pixel (0, 0) of
+        the rectangle described by the PixelArray property, a width and an
+        height.
+
+        Each rectangle described by this property represents the maximum image
+        size that the camera module can produce for a given image resolution.
+
+        Example 1.
+        A sensor which only produces images in the 4:3 image resolution will
+        report a single ActiveArea rectangle, from which all other image formats
+        are obtained by either cropping the field-of-view and/or applying pixel
+        sub-sampling techniques such as pixel skipping or binning.
+
+                        PixelArray(0)
+                    /-----------------/
+                      x1          x2
+            (0,0)-> +-o------------o-+  /
+                 y1 o +------------+ |  |
+                    | |////////////| |  |
+                    | |////////////| |  | PixelArray(1)
+                    | |////////////| |  |
+                 y2 o +------------+ |  |
+                    +----------------+  /
+
+        The property reports a single rectangle
+
+                 ActiveArea = (x1, y1, (x2 - x1), (y2 - y1))
+
+        Example 2
+        A camera sensor which can produce images in different native
+        resolutions, will report several overlapping rectangle, one for each
+        natively supported resolution, ordered from the tallest to the shortest
+        one.
+
+                        PixelArray(0)
+                    /-----------------/
+                     x1  x2    x3  x4
+            (0,0)-> +o---o------o---o+  /
+                 y1 |    +------+    |  |
+                    |    |//////|    |  |
+                 y2 o+---+------+---+|  |
+                    ||///|//////|///||  | PixelArray(1)
+                 y3 o+---+------+---+|  |
+                    |    |//////|    |  |
+                 y4 |    +------+    |  |
+                    +----+------+----+  /
+
+        The property reports two rectangles
+
+                PixelArray = ( (x2, y1, (x3 - x2), (y4 - 1),
+                               (x1, y2, (x4 - x1), (y3 - y2))
+
+        The first rectangle describes the maximum field-of-view of all image
+        formats in the 4:3 resolutions, while the second one describes the
+        maximum field of view for all image formats in the 16:9 resolutions.
+
+  - BayerFilterArrangement:
+      type: int32_t
+      description: |
+        The pixel array color filter displacement.
+
+        This property describes the arrangement and readout sequence of the
+        three RGB color components of the sensor's Bayer Color Filter Array
+        (CFA).
+
+        Color filters are usually displaced in line-alternating fashion on the
+        sensor pixel array. In example, one line might be composed of Red-Green
+        while the successive is composed of Blue-Green color information.
+
+        The value of this property represents the arrangement of color filters
+        in the top-left 2x2 pixel square.
+
+        For example, for a sensor with the following color filter displacement
+
+                 (0, 0)               (max-col)
+           +---+    +--------------...---+
+           |B|G|<---|B|G|B|G|B|G|B|...B|G|
+           |G|R|<---|G|R|G|R|G|R|G|...G|R|
+           +---+    |B|G|B|G|B|G|B|...B|G|
+                    ...                  ..
+                    ...                  ..
+                    |G|R|G|R|G|R|G|...G|R|
+                    |B|G|B|G|B|G|B|...B|G|   (max-lines)
+                    +--------------...---+
+
+        The filter arrangement is represented by the BGGR value, which
+        correspond to the pixel readout sequence in line interleaved mode.
+
+      enum:
+        - name: BayerFilterRGGB
+          value: 0
+          description: |
+            Color filter array displacement is Red-Green/Green-Blue
+
+        - name: BayerFilterGRBG
+          value: 1
+          description: |
+            Color filter array displacement is Green-Red/Blue-Green
+
+        - name: BayerFilterGBRG
+          value: 2
+          description: |
+            Color filter array displacement is Green-Blue/Red-Green
+
+        - name: BayerFilterBGGR
+          value: 3
+          description: |
+            Color filter array displacement is Blue-Green/Green-Red
+
+        - name: BayerFilterNonStandard
+          value: 4
+          description: |
+            The pixel array color filter does not use the standard Bayer RGB
+            color model
+
+  - ISOSensitivityRange:
+      type: int32_t
+      size: [2]
+      description: |
+        The range of supported ISO sensitivities, as documented by the
+        ISO 12232:2006 (or later) standard.
+
 ...
-- 
2.26.1