From a4e82c950be0f3a06e6b6fe8970ff7b281ee146c Mon Sep 17 00:00:00 2001 From: Bryan O'Donoghue Date: Tue, 6 Jan 2026 17:00:42 +0000 Subject: [PATCH] libcamera: shaders: Extend debayer shaders to apply CCM gains Extend Bayer shaders to support application of a passed CCM table. Reviewed-by: Milan Zamazal Tested-by: Robert Mader Tested-by: Hans de Goede # ThinkPad T14s gen 6 (arm64) ov02c10 + X1c gen 12 ov08x40 Tested-by: Kieran Bingham # Lenovo X13s Signed-off-by: Bryan O'Donoghue Signed-off-by: Kieran Bingham --- src/libcamera/shaders/bayer_1x_packed.frag | 45 +++++++++++++++++++ src/libcamera/shaders/bayer_unpacked.frag | 51 +++++++++++++++++++++- 2 files changed, 95 insertions(+), 1 deletion(-) diff --git a/src/libcamera/shaders/bayer_1x_packed.frag b/src/libcamera/shaders/bayer_1x_packed.frag index 19b13ad0..171a928c 100644 --- a/src/libcamera/shaders/bayer_1x_packed.frag +++ b/src/libcamera/shaders/bayer_1x_packed.frag @@ -65,6 +65,7 @@ uniform vec2 tex_step; uniform vec2 tex_bayer_first_red; uniform sampler2D tex_y; +uniform mat3 ccm; void main(void) { @@ -212,5 +213,49 @@ void main(void) vec3(patterns.y, C, patterns.x) : vec3(patterns.wz, C)); + /* + * CCM is a 3x3 in the format + * + * +--------------+----------------+---------------+ + * | RedRedGain | RedGreenGain | RedBlueGain | + * +--------------+----------------+---------------+ + * | GreenRedGain | GreenGreenGain | GreenBlueGain | + * +--------------+----------------+---------------+ + * | BlueRedGain | BlueGreenGain | BlueBlueGain | + * +--------------+----------------+---------------+ + * + * Rout = RedRedGain * Rin + RedGreenGain * Gin + RedBlueGain * Bin + * Gout = GreenRedGain * Rin + GreenGreenGain * Gin + GreenBlueGain * Bin + * Bout = BlueRedGain * Rin + BlueGreenGain * Gin + BlueBlueGain * Bin + * + * We upload to the GPU without transposition glUniformMatrix3f(.., .., GL_FALSE, ccm); + * + * CPU + * float ccm [] = { + * RedRedGain, RedGreenGain, RedBlueGain, + * GreenRedGain, GreenGreenGain, GreenBlueGain, + * BlueRedGain, BlueGreenGain, BlueBlueGain, + * }; + * + * GPU + * ccm = { + * RedRedGain, GreenRedGain, BlueRedGain, + * RedGreenGain, GreenGreenGain, BlueGreenGain, + * RedBlueGain, GreenBlueGain, BlueBlueGain, + * } + * + * However the indexing for the mat data-type is column major hence + * ccm[0][0] = RedRedGain, ccm[0][1] = RedGreenGain, ccm[0][2] = RedBlueGain + * + */ + float rin, gin, bin; + rin = rgb.r; + gin = rgb.g; + bin = rgb.b; + + rgb.r = (rin * ccm[0][0]) + (gin * ccm[0][1]) + (bin * ccm[0][2]); + rgb.g = (rin * ccm[1][0]) + (gin * ccm[1][1]) + (bin * ccm[1][2]); + rgb.b = (rin * ccm[2][0]) + (gin * ccm[2][1]) + (bin * ccm[2][2]); + gl_FragColor = vec4(rgb, 1.0); } diff --git a/src/libcamera/shaders/bayer_unpacked.frag b/src/libcamera/shaders/bayer_unpacked.frag index aa7a1b00..c41d72f4 100644 --- a/src/libcamera/shaders/bayer_unpacked.frag +++ b/src/libcamera/shaders/bayer_unpacked.frag @@ -24,8 +24,11 @@ uniform sampler2D tex_y; varying vec4 center; varying vec4 yCoord; varying vec4 xCoord; +uniform mat3 ccm; void main(void) { + vec3 rgb; + #define fetch(x, y) texture2D(tex_y, vec2(x, y)).r float C = texture2D(tex_y, center.xy).r; // ( 0, 0) @@ -97,11 +100,57 @@ void main(void) { PATTERN.xw += kB.xw * B; PATTERN.xz += kF.xz * F; - gl_FragColor.rgb = (alternate.y == 0.0) ? + rgb = (alternate.y == 0.0) ? ((alternate.x == 0.0) ? vec3(C, PATTERN.xy) : vec3(PATTERN.z, C, PATTERN.w)) : ((alternate.x == 0.0) ? vec3(PATTERN.w, C, PATTERN.z) : vec3(PATTERN.yx, C)); + + /* + * CCM is a 3x3 in the format + * + * +--------------+----------------+---------------+ + * | RedRedGain | RedGreenGain | RedBlueGain | + * +--------------+----------------+---------------+ + * | GreenRedGain | GreenGreenGain | GreenBlueGain | + * +--------------+----------------+---------------+ + * | BlueRedGain | BlueGreenGain | BlueBlueGain | + * +--------------+----------------+---------------+ + * + * Rout = RedRedGain * Rin + RedGreenGain * Gin + RedBlueGain * Bin + * Gout = GreenRedGain * Rin + GreenGreenGain * Gin + GreenBlueGain * Bin + * Bout = BlueRedGain * Rin + BlueGreenGain * Gin + BlueBlueGain * Bin + * + * We upload to the GPU without transposition glUniformMatrix3f(.., .., GL_FALSE, ccm); + * + * CPU + * float ccm [] = { + * RedRedGain, RedGreenGain, RedBlueGain, + * GreenRedGain, GreenGreenGain, GreenBlueGain, + * BlueRedGain, BlueGreenGain, BlueBlueGain, + * }; + * + * GPU + * ccm = { + * RedRedGain, GreenRedGain, BlueRedGain, + * RedGreenGain, GreenGreenGain, BlueGreenGain, + * RedBlueGain, GreenBlueGain, BlueBlueGain, + * } + * + * However the indexing for the mat data-type is column major hence + * ccm[0][0] = RedRedGain, ccm[0][1] = RedGreenGain, ccm[0][2] = RedBlueGain + * + */ + float rin, gin, bin; + rin = rgb.r; + gin = rgb.g; + bin = rgb.b; + + rgb.r = (rin * ccm[0][0]) + (gin * ccm[0][1]) + (bin * ccm[0][2]); + rgb.g = (rin * ccm[1][0]) + (gin * ccm[1][1]) + (bin * ccm[1][2]); + rgb.b = (rin * ccm[2][0]) + (gin * ccm[2][1]) + (bin * ccm[2][2]); + + gl_FragColor.rgb = rgb; }