[{"id":39735,"web_url":"https://patchwork.libcamera.org/comment/39735/","msgid":"<85ech4mey1.fsf@mzamazal-thinkpadp1gen7.tpbc.csb>","date":"2026-07-15T15:48:38","subject":"Re: [RFC PATCH v7 6/6] libcamera: software_isp: debayer_egl: Add\n\tLSC support","submitter":{"id":177,"url":"https://patchwork.libcamera.org/api/people/177/","name":"Milan Zamazal","email":"mzamazal@redhat.com"},"content":"Milan Zamazal writes:\n\n> From: Xander Pronk \n>\n> Add support for passing the LSC table from debayerParams to the shaders.\n>\n> The LSC table values are floats, we must add `type' parameter to\n> createTexture2D to support this. Moreover, we use 16-bit internal\n> format for the values, primarily because this works for me, unlike\n> 32-bit floats.\n>\n> Co-developed-by: Rick ten Wolde \n> Signed-off-by: Rick ten Wolde \n> Signed-off-by: Xander Pronk \n> Signed-off-by: Milan Zamazal \n> ---\n> include/libcamera/internal/egl.h | 6 +++-\n> .../internal/software_isp/debayer_params.h | 2 ++\n> src/libcamera/egl.cpp | 10 ++++--\n> src/libcamera/software_isp/debayer.cpp | 5 +++\n> src/libcamera/software_isp/debayer_egl.cpp | 32 +++++++++++++++++--\n> src/libcamera/software_isp/debayer_egl.h | 7 ++++\n> 6 files changed, 57 insertions(+), 5 deletions(-)\n>\n> diff --git a/include/libcamera/internal/egl.h b/include/libcamera/internal/egl.h\n> index 030c813a5..37da2b18a 100644\n> --- a/include/libcamera/internal/egl.h\n> +++ b/include/libcamera/internal/egl.h\n> @@ -107,7 +107,11 @@ public:\n> \n> \tint createInputDMABufTexture2D(eGLImage &eglImage, int fd);\n> \tint createOutputDMABufTexture2D(eGLImage &eglImage, int fd);\n> -\tvoid createTexture2D(eGLImage &eglImage, void *data, GLint filter);\n> +\tvoid createTexture2D(eGLImage &eglImage,\n> +\t\t\t GLint internalFormat,\n> +\t\t\t GLenum type,\n> +\t\t\t const void *data,\n> +\t\t\t GLint filter);\n> \n> \tvoid pushEnv(std::vector &shaderEnv, const char *str);\n> \tvoid makeCurrent();\n> diff --git a/include/libcamera/internal/software_isp/debayer_params.h b/include/libcamera/internal/software_isp/debayer_params.h\n> index 4eb6c7e8d..0b96d4ffe 100644\n> --- a/include/libcamera/internal/software_isp/debayer_params.h\n> +++ b/include/libcamera/internal/software_isp/debayer_params.h\n> @@ -30,6 +30,8 @@ struct DebayerParams {\n> \tstatic constexpr unsigned int kLscGridSize = 16;\n> \tstatic constexpr unsigned int kLscValuesPerCell = 3;\n> \tusing LscValueType = float;\n> +\tstatic constexpr unsigned int kLscBytesPerCell =\n> +\t\tkLscValuesPerCell * sizeof(LscValueType);\n> \tusing LscLookupTable =\n> \t\tstd::array;\n> \tLscLookupTable lscLut{};\n> diff --git a/src/libcamera/egl.cpp b/src/libcamera/egl.cpp\n> index aeac5d313..c2a158ce7 100644\n> --- a/src/libcamera/egl.cpp\n> +++ b/src/libcamera/egl.cpp\n> @@ -241,6 +241,8 @@ int eGL::createOutputDMABufTexture2D(eGLImage &eglImage, int fd)\n> /**\n> * \\brief Create a 2D texture from a memory buffer\n> * \\param[in,out] eglImage EGL image to associate with the texture\n> + * \\param[in] internalFormat OpenGL internal storage format (e.g., GL_RGB8, GL_RGBA8)\n> + * \\param[in] type OpenGL pixel data type (e.g., GL_UNSIGNED_BYTE, GL_FLOAT)\n> * \\param[in] data Pointer to pixel data, or nullptr for uninitialised texture\n> * \\param[in] filter GL texture filter setting\n> *\n> @@ -249,7 +251,11 @@ int eGL::createOutputDMABufTexture2D(eGLImage &eglImage, int fd)\n> * is useful for uploading static data like lookup tables or uniform color\n> * matrices to the GPU.\n> */\n> -void eGL::createTexture2D(eGLImage &eglImage, void *data, GLint filter)\n> +void eGL::createTexture2D(eGLImage &eglImage,\n> +\t\t\t GLint internalFormat,\n> +\t\t\t GLenum type,\n> +\t\t\t const void *data,\n> +\t\t\t GLint filter)\n> {\n> \tASSERT(tid_ == Thread::currentId());\n> \n> @@ -257,7 +263,7 @@ void eGL::createTexture2D(eGLImage &eglImage, void *data, GLint filter)\n> \tglBindTexture(GL_TEXTURE_2D, eglImage.texture_);\n> \n> \t// Generate texture, bind, associate image to texture, configure, unbind\n> -\tglTexImage2D(GL_TEXTURE_2D, 0, eglImage.format_, eglImage.width_, eglImage.height_, 0, eglImage.format_, GL_UNSIGNED_BYTE, data);\n> +\tglTexImage2D(GL_TEXTURE_2D, 0, internalFormat, eglImage.width_, eglImage.height_, 0, eglImage.format_, type, data);\n> \n> \t// Nearest filtering\n> \tglTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, filter);\n> diff --git a/src/libcamera/software_isp/debayer.cpp b/src/libcamera/software_isp/debayer.cpp\n> index 5c4bd914b..2bf64e570 100644\n> --- a/src/libcamera/software_isp/debayer.cpp\n> +++ b/src/libcamera/software_isp/debayer.cpp\n> @@ -58,6 +58,11 @@ namespace libcamera {\n> * \\brief Type of LSC grid values\n> */\n> \n> +/**\n> + * \\var DebayerParams::kLscBytesPerCell\n> + * \\brief Number of bytes per each of the lens shading grid areas\n> + */\n> +\n> /**\n> * \\typedef DebayerParams::LscLookupTable\n> * \\brief Lookup table for lens shading correction\n> diff --git a/src/libcamera/software_isp/debayer_egl.cpp b/src/libcamera/software_isp/debayer_egl.cpp\n> index 562e9fc7a..a73a00759 100644\n> --- a/src/libcamera/software_isp/debayer_egl.cpp\n> +++ b/src/libcamera/software_isp/debayer_egl.cpp\n> @@ -128,6 +128,9 @@ int DebayerEGL::getShaderVariableLocations(void)\n> \ttextureUniformBayerFirstRed_ = glGetUniformLocation(programId_, \"tex_bayer_first_red\");\n> \ttextureUniformProjMatrix_ = glGetUniformLocation(programId_, \"proj_matrix\");\n> \n> +\ttextureUniformLsc_ = glGetUniformLocation(programId_, \"lsc_tex\");\n> +\tlscEnabledUniform_ = glGetUniformLocation(programId_, \"lsc_enabled\");\n> +\n> \tLOG(Debayer, Debug) << \"vertexIn \" << attributeVertex_ << \" textureIn \" << attributeTexture_\n> \t\t\t << \" tex_y \" << textureUniformBayerDataIn_\n> \t\t\t << \" awb \" << awbUniformDataIn_\n> @@ -139,7 +142,9 @@ int DebayerEGL::getShaderVariableLocations(void)\n> \t\t\t << \" tex_size \" << textureUniformSize_\n> \t\t\t << \" stride_factor \" << textureUniformStrideFactor_\n> \t\t\t << \" tex_bayer_first_red \" << textureUniformBayerFirstRed_\n> -\t\t\t << \" proj_matrix \" << textureUniformProjMatrix_;\n> +\t\t\t << \" proj_matrix \" << textureUniformProjMatrix_\n> +\t\t\t << \" tex_lsc \" << textureUniformLsc_\n> +\t\t\t << \" lsc_enabled\" << lscEnabledUniform_;\n> \treturn 0;\n> }\n> \n> @@ -156,6 +161,9 @@ int DebayerEGL::initBayerShaders(PixelFormat inputFormat, PixelFormat outputForm\n> \t/* Specify GL_OES_EGL_image_external */\n> \tegl_.pushEnv(shaderEnv, \"#extension GL_OES_EGL_image_external: enable\");\n> \n> +\tif (lscEnabled_)\n> +\t\tegl_.pushEnv(shaderEnv, \"#define APPLY_LSC\");\n> +\n> \t/*\n> \t * Tell shaders how to re-order output taking account of how the pixels\n> \t * are actually stored by EGL.\n> @@ -348,6 +356,18 @@ int DebayerEGL::configure(const StreamConfiguration &inputCfg,\n> \t */\n> \tstats_->setWindow(Rectangle(window_.size()));\n> \n> +\tif (lscEnabled_) {\n> +\t\tconstexpr unsigned int gridSize = DebayerParams::kLscGridSize;\n> +\t\tconst unsigned int stride = gridSize * DebayerParams::kLscBytesPerCell;\n> +\t\teglImageLscLookup_ =\n> +\t\t\tstd::make_unique(GL_RGB,\n> +\t\t\t\t\t\t gridSize,\n> +\t\t\t\t\t\t gridSize,\n> +\t\t\t\t\t\t stride,\n> +\t\t\t\t\t\t GL_TEXTURE2,\n> +\t\t\t\t\t\t 2);\n> +\t}\n> +\n> \treturn 0;\n> }\n> \n> @@ -483,6 +503,13 @@ void DebayerEGL::setShaderVariableValues(const DebayerParams ¶ms)\n> \tglUniformMatrix3fv(ccmUniformDataIn_, 1, GL_TRUE, params.combinedMatrix.data().data());\n> \tLOG(Debayer, Debug) << \" ccmUniformDataIn_ \" << ccmUniformDataIn_ << \" data \" << params.combinedMatrix;\n> \n> +\tif (lscEnabled_) {\n> +\t\tegl_.createTexture2D(*eglImageLscLookup_, GL_RGB16F, GL_FLOAT,\n> +\t\t\t\t params.lscLut.data(), GL_LINEAR);\n> +\t\tglUniform1i(textureUniformLsc_, eglImageLscLookup_->texture_unit_uniform_id_);\n> +\t\tglUniform1i(lscEnabledUniform_, params.lscEnabled);\n> +\t}\n> +\n> \t/*\n> \t * 0 = Red, 1 = Green, 2 = Blue\n> \t */\n> @@ -530,7 +557,8 @@ int DebayerEGL::debayerGPU(FrameBuffer *input, FrameBuffer *output, const Debaye\n> \t\t\tLOG(Debayer, Error) << \"mmap-ing buffer(s) failed\";\n> \t\t\treturn -ENODEV;\n> \t\t}\n> -\t\tegl_.createTexture2D(*eglImageBayerIn_, inMapped->value().planes()[0].data(), GL_NEAREST);\n> +\t\tegl_.createTexture2D(*eglImageBayerIn_, glFormat_, GL_UNSIGNED_BYTE,\n> +\t\t\t\t inMapped->value().planes()[0].data(), GL_NEAREST);\n> \t}\n> \n> \t/* Generate the output render framebuffer as render to texture */\n> diff --git a/src/libcamera/software_isp/debayer_egl.h b/src/libcamera/software_isp/debayer_egl.h\n> index 82ed1305d..2af26fb74 100644\n> --- a/src/libcamera/software_isp/debayer_egl.h\n> +++ b/src/libcamera/software_isp/debayer_egl.h\n> @@ -78,7 +78,10 @@ private:\n> \tstd::unique_ptr eglImageBayerIn_;\n> \tstd::unique_ptr eglImageBayerOut_;\n> \n> +\t/* LSC lookup table */\n> +\tstd::unique_ptr eglImageLscLookup_;\n> \tbool lscEnabled_;\n> +\n> \t/* Shader parameters */\n> \tfloat firstRed_x_;\n> \tfloat firstRed_y_;\n> @@ -95,6 +98,10 @@ private:\n> \t/* Per-frame AWB gains */\n> \tGLint awbUniformDataIn_;\n> \n> +\t/* Lens shading correction */\n> +\tGLint textureUniformLsc_;\n> +\tGLboolean lscEnabledUniform_;\n\nThis must be GLint.\n\n> +\n> \t/* Represent per-frame CCM as a uniform vector of floats 3 x 3 */\n> \tGLint ccmUniformDataIn_;","headers":{"Return-Path":"","X-Original-To":"parsemail@patchwork.libcamera.org","Delivered-To":"parsemail@patchwork.libcamera.org","Received":["from 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