[libcamera-devel] [PATCH 1/1] libcamera: controls: Add controls for HDR

[David Plowman]

We add an HdrMode control (to enable and disable HDR processing)
and an HdrChannel, which indicates what kind of HDR frame (short, long
medium) has just arrived.

Currently the HdrMode supports three values:

* Off - no HDR processing at all.
* MultiExposure - frames at multiple different exposures are combined
  to create HDR images.
* SingleExposure - multiple frames all at the same exposure are
  combined to create HDR images.

Signed-off-by: David Plowman <david.plowman at raspberrypi.com>
---
 src/libcamera/control_ids.yaml | 47 ++++++++++++++++++++++++++++++++++
 1 file changed, 47 insertions(+)

diff --git a/src/libcamera/control_ids.yaml b/src/libcamera/control_ids.yaml
index 056886e6..34df7adb 100644
--- a/src/libcamera/control_ids.yaml
+++ b/src/libcamera/control_ids.yaml
@@ -701,6 +701,53 @@ controls:
             Continuous AF is paused. No further state changes or lens movements
             will occur until the AfPauseResume control is sent.
 
+  - HdrMode:
+      type: int32_t
+      description: |
+        Control to set the mode to be used for High Dynamic Range (HDR)
+        imaging.
+
+      enum:
+        - name: HdrModeOff
+          value: 0
+          description: |
+            HDR is not enabled.
+        - name: HdrModeMultiExposure
+          value: 1
+          description: |
+            Multiple exposures will be used to create HDR images.
+        - name: HdrModeSingleExposure
+          value: 2
+          description: |
+            Multiple frames all at a single exposure will be used to create HDR
+            images.
+
+  - HdrChannel:
+      type: int32_t
+      description: |
+        This value is reported back to the application so that it can discover
+        whether this capture corresponds to the short or long exposure image (or
+        any other image used by the HDR procedure).
+
+      enum:
+        - name: HdrChannelNone
+          value: 0
+          description: |
+            This image does not correspond to any of the captures used to create
+            an HDR image.
+        - name: HdrChannelShort
+          value: 1
+          description: |
+            This is a short exposure image.
+        - name: HdrChannelMedium
+          value: 2
+          description: |
+            This is a medium exposure image.
+        - name: HdrChannelLong
+          value: 3
+          description: |
+            This is a long exposure image.
+
   # ----------------------------------------------------------------------------
   # Draft controls section
 
-- 
2.30.2