[RFC,v4,5/7] libcamera: shaders: Add LSC support
diff mbox series

Message ID 20260504182658.590233-6-mzamazal@redhat.com
State New
Headers show
Series
  • LSC for SoftISP simple pipeline
Related show

Commit Message

Milan Zamazal May 4, 2026, 6:26 p.m. UTC 
From: Xander Pronk <xander.c.pronk@gmail.com>

Lens shading correction should be applied after black level
subtraction (in order to make the computations with meaningful values)
and before white balance (especially before white balance stats are
computed).

Note that lens shading correction depends on temperature, which is
computed from the preceding, rather than current, frame (this is due to
how white balance is currently computed).

Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Co-developed-by: Rick ten Wolde <rick_libcamera@wolde.info>
Signed-off-by: Rick ten Wolde <rick_libcamera@wolde.info>
Signed-off-by: Xander Pronk <xander.c.pronk@gmail.com>
Signed-off-by: Milan Zamazal <mzamazal@redhat.com>
---
 src/libcamera/shaders/bayer_1x_packed.frag | 8 ++++++++
 src/libcamera/shaders/bayer_unpacked.frag  | 8 ++++++++
 2 files changed, 16 insertions(+)

Patch
diff mbox series 

diff --git a/src/libcamera/shaders/bayer_1x_packed.frag b/src/libcamera/shaders/bayer_1x_packed.frag
index 23747f78a..228c72309 100644
--- a/src/libcamera/shaders/bayer_1x_packed.frag
+++ b/src/libcamera/shaders/bayer_1x_packed.frag
@@ -70,6 +70,10 @@  uniform vec3 blacklevel;
 uniform float gamma;
 uniform float contrastExp;
 
+#if defined(APPLY_LSC)
+uniform sampler2D lsc_tex;
+#endif
+
 float apply_contrast(float value)
 {
 	// Apply simple S-curve
@@ -227,6 +231,10 @@  void main(void)
 
 	rgb = rgb - blacklevel;
 
+#if defined(APPLY_LSC)
+	rgb = rgb * texture2D(lsc_tex, textureOut).rgb;
+#endif
+
 	/*
 	 *   CCM is a 3x3 in the format
 	 *
diff --git a/src/libcamera/shaders/bayer_unpacked.frag b/src/libcamera/shaders/bayer_unpacked.frag
index 1b85196ae..af87bcc0f 100644
--- a/src/libcamera/shaders/bayer_unpacked.frag
+++ b/src/libcamera/shaders/bayer_unpacked.frag
@@ -29,6 +29,10 @@  uniform vec3            blacklevel;
 uniform float           gamma;
 uniform float           contrastExp;
 
+#if defined(APPLY_LSC)
+uniform sampler2D lsc_tex;
+#endif
+
 float apply_contrast(float value)
 {
     // Apply simple S-curve
@@ -130,6 +134,10 @@  void main(void) {
 
     rgb = rgb - blacklevel;
 
+#if defined(APPLY_LSC)
+    rgb = rgb * texture2D(lsc_tex, center.xy).rgb;
+#endif
+
     /*
      *   CCM is a 3x3 in the format
      *