[v2,3/4] software-isp: Meter the visible sensor crop
diff mbox series

Message ID 20261015223604.311616-4-halfline@gmail.com
State New
Headers show
Series
  • software-isp: Align GPU cropping and statistics
Related show

Commit Message

Ray Strode Oct. 15, 2026, 10:36 p.m. UTC 
From: Ray Strode <rstrode@redhat.com>

The GPU debayer path draws a centered sensor crop into the requested output
size, while CPU statistics read the original input buffer.

The statistics window still follows the output dimensions, so metering
covers a different part of the sensor when output sizes or aspect ratios
change.

This commit derives the visible crop in sensor coordinates and centers the
statistics window on that region.

Signed-off-by: Ray Strode <rstrode@redhat.com>
---
 .../internal/software_isp/debayer_geometry.h        |  8 ++++++++
 src/libcamera/software_isp/debayer_egl.cpp          | 13 +++----------
 src/libcamera/software_isp/debayer_egl.h            |  1 -
 3 files changed, 11 insertions(+), 11 deletions(-)

Patch
diff mbox series 

diff --git a/include/libcamera/internal/software_isp/debayer_geometry.h b/include/libcamera/internal/software_isp/debayer_geometry.h
index 6c10ecb8..c6359cde 100644
--- a/include/libcamera/internal/software_isp/debayer_geometry.h
+++ b/include/libcamera/internal/software_isp/debayer_geometry.h
@@ -38,4 +38,12 @@  inline std::array<float, 16> debayerProjection(const Size &inputSize,
 	};
 }
 
+/* Return the visible sensor rectangle, before statistics Bayer alignment. */
+inline Rectangle debayerCrop(const Size &inputSize, const Size &nativeSize,
+			     const Size &outputSize)
+{
+	const Size visibleSize = nativeSize.boundedToAspectRatio(outputSize);
+	return visibleSize.centeredTo(Rectangle(inputSize).center());
+}
+
 } /* namespace libcamera */
diff --git a/src/libcamera/software_isp/debayer_egl.cpp b/src/libcamera/software_isp/debayer_egl.cpp
index 1a7ad25c..9f3dc752 100644
--- a/src/libcamera/software_isp/debayer_egl.cpp
+++ b/src/libcamera/software_isp/debayer_egl.cpp
@@ -323,18 +323,11 @@  int DebayerEGL::configure(const StreamConfiguration &inputCfg,
 	outputSize_ = outputCfg.size;
 	nativeOutputSize_ = outSizeRange.max;
 
-	window_.x = ((inputCfg.size.width - outputCfg.size.width) / 2) &
-		    ~(inputConfig_.patternSize.width - 1);
-	window_.y = ((inputCfg.size.height - outputCfg.size.height) / 2) &
-		    ~(inputConfig_.patternSize.height - 1);
-	window_.width = outputCfg.size.width;
-	window_.height = outputCfg.size.height;
-
 	/*
-	 * Don't pass x,y from window_ since process() already adjusts for it.
-	 * But crop the window to 2/3 of its width and height for speedup.
+	 * The GPU scales the visible sensor crop to outputSize_. Statistics
+	 * consume the original input buffer, so use sensor coordinates here.
 	 */
-	stats_->setWindow(Rectangle(window_.size()));
+	stats_->setWindow(debayerCrop(inputCfg.size, nativeOutputSize_, outputSize_));
 
 	inputBufferCount_ = inputCfg.bufferCount;
 	outputBufferCount_ = outputCfg.bufferCount;
diff --git a/src/libcamera/software_isp/debayer_egl.h b/src/libcamera/software_isp/debayer_egl.h
index 30e51a47..52b8aa07 100644
--- a/src/libcamera/software_isp/debayer_egl.h
+++ b/src/libcamera/software_isp/debayer_egl.h
@@ -111,7 +111,6 @@  private:
 	GLint contrastExpUniformDataIn_;
 
 	Size nativeOutputSize_;
-	Rectangle window_;
 	std::unique_ptr<SwStatsCpu> stats_;
 	eGL egl_;
 	uint32_t width_;