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{
    "id": 25797,
    "url": "https://patchwork.libcamera.org/api/1.1/patches/25797/?format=api",
    "web_url": "https://patchwork.libcamera.org/patch/25797/",
    "project": {
        "id": 1,
        "url": "https://patchwork.libcamera.org/api/1.1/projects/1/?format=api",
        "name": "libcamera",
        "link_name": "libcamera",
        "list_id": "libcamera_core",
        "list_email": "libcamera-devel@lists.libcamera.org",
        "web_url": "",
        "scm_url": "",
        "webscm_url": ""
    },
    "msgid": "<20260114173918.1744023-2-kieran.bingham@ideasonboard.com>",
    "date": "2026-01-14T17:39:01",
    "name": "[v5,01/16] ipa: libipa: Provide a Quantized data type support",
    "commit_ref": null,
    "pull_url": null,
    "state": "superseded",
    "archived": false,
    "hash": "007b0507f7d11b893cdac1602cbc42b4aa32fa96",
    "submitter": {
        "id": 4,
        "url": "https://patchwork.libcamera.org/api/1.1/people/4/?format=api",
        "name": "Kieran Bingham",
        "email": "kieran.bingham@ideasonboard.com"
    },
    "delegate": null,
    "mbox": "https://patchwork.libcamera.org/patch/25797/mbox/",
    "series": [
        {
            "id": 5708,
            "url": "https://patchwork.libcamera.org/api/1.1/series/5708/?format=api",
            "web_url": "https://patchwork.libcamera.org/project/libcamera/list/?series=5708",
            "date": "2026-01-14T17:39:00",
            "name": "libipa: Introduce a Quantized type",
            "version": 5,
            "mbox": "https://patchwork.libcamera.org/series/5708/mbox/"
        }
    ],
    "comments": "https://patchwork.libcamera.org/api/patches/25797/comments/",
    "check": "pending",
    "checks": "https://patchwork.libcamera.org/api/patches/25797/checks/",
    "tags": {},
    "headers": {
        "Return-Path": "<libcamera-devel-bounces@lists.libcamera.org>",
        "X-Original-To": "parsemail@patchwork.libcamera.org",
        "Delivered-To": "parsemail@patchwork.libcamera.org",
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            "from lancelot.ideasonboard.com (lancelot.ideasonboard.com\n\t[92.243.16.209])\n\tby patchwork.libcamera.org (Postfix) with ESMTPS id 6F062BDCBF\n\tfor <parsemail@patchwork.libcamera.org>;\n\tWed, 14 Jan 2026 17:39:30 +0000 (UTC)",
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        "From": "Kieran Bingham <kieran.bingham@ideasonboard.com>",
        "To": "libcamera devel <libcamera-devel@lists.libcamera.org>",
        "Cc": "Kieran Bingham <kieran.bingham@ideasonboard.com>,\n\tIsaac Scott <isaac.scott@ideasonboard.com>",
        "Subject": "[PATCH v5 01/16] ipa: libipa: Provide a Quantized data type support",
        "Date": "Wed, 14 Jan 2026 17:39:01 +0000",
        "Message-ID": "<20260114173918.1744023-2-kieran.bingham@ideasonboard.com>",
        "X-Mailer": "git-send-email 2.52.0",
        "In-Reply-To": "<20260114173918.1744023-1-kieran.bingham@ideasonboard.com>",
        "References": "<20260114173918.1744023-1-kieran.bingham@ideasonboard.com>",
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        "X-BeenThere": "libcamera-devel@lists.libcamera.org",
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        "Sender": "\"libcamera-devel\" <libcamera-devel-bounces@lists.libcamera.org>"
    },
    "content": "Frequently when handling data in IPA components we must convert and\nstore user interface values which may be floating point values, and\nperform a specific operation or conversion to quantize this to a\nhardware value.\n\nThis value may be to a fixed point type, or more custom code mappings,\nbut in either case it is important to contain both the required hardware\nvalue, with its effective quantized value.\n\nProvide a new storage type 'Quantized' which can be defined based on a\nset of type specific Traits to perform the conversions between floats\nand the underlying hardware type.\n\nReviewed-by: Isaac Scott <isaac.scott@ideasonboard.com>\nSigned-off-by: Kieran Bingham <kieran.bingham@ideasonboard.com>\n\n---\nv3:\n - adapt string format to [0xff:1.99] style instead of Q:0xff V:1.99\n - Clean up comments and copyright\n - Remove private initialisers - already handled by constructors\n - Change quantized_type to QuantizedType\n\nv5:\n- introduce operator<<(std::ostream &out, const Quantized<Traits> &q)\n- Remove unused iomanip and stdint.h from includes\n\nSigned-off-by: Kieran Bingham <kieran.bingham@ideasonboard.com>\n---\n src/ipa/libipa/meson.build   |   2 +\n src/ipa/libipa/quantized.cpp | 142 +++++++++++++++++++++++++++++++++++\n src/ipa/libipa/quantized.h   |  83 ++++++++++++++++++++\n 3 files changed, 227 insertions(+)\n create mode 100644 src/ipa/libipa/quantized.cpp\n create mode 100644 src/ipa/libipa/quantized.h",
    "diff": "diff --git a/src/ipa/libipa/meson.build b/src/ipa/libipa/meson.build\nindex 7202df869c2f..963c5ee73063 100644\n--- a/src/ipa/libipa/meson.build\n+++ b/src/ipa/libipa/meson.build\n@@ -17,6 +17,7 @@ libipa_headers = files([\n     'lux.h',\n     'module.h',\n     'pwl.h',\n+    'quantized.h',\n     'v4l2_params.h',\n ])\n \n@@ -37,6 +38,7 @@ libipa_sources = files([\n     'lux.cpp',\n     'module.cpp',\n     'pwl.cpp',\n+    'quantized.cpp',\n     'v4l2_params.cpp',\n ])\n \ndiff --git a/src/ipa/libipa/quantized.cpp b/src/ipa/libipa/quantized.cpp\nnew file mode 100644\nindex 000000000000..115739e71654\n--- /dev/null\n+++ b/src/ipa/libipa/quantized.cpp\n@@ -0,0 +1,142 @@\n+/* SPDX-License-Identifier: LGPL-2.1-or-later */\n+/*\n+ * Copyright (C) 2025, Ideas On Board Oy\n+ *\n+ * Helper class to manage conversions between floating point types and quantized\n+ * storage and representation of those values.\n+ */\n+\n+#include \"quantized.h\"\n+\n+/**\n+ * \\file quantized.h\n+ * \\brief Quantized storage and Quantizer representations\n+ */\n+\n+namespace libcamera {\n+\n+namespace ipa {\n+\n+/**\n+ * \\struct libcamera::ipa::Quantized\n+ * \\brief Wrapper that stores a value in both quantized and floating-point form\n+ * \\tparam Traits The traits class defining the quantization behaviour\n+ *\n+ * The Quantized struct template provides a thin wrapper around a quantized\n+ * representation of a floating-point value. It uses a traits type \\a Traits\n+ * to define the conversion policy between the floating-point domain and the\n+ * quantized integer domain.\n+ *\n+ * Each Quantized instance maintains two synchronized members:\n+ *  - the quantized integer representation, and\n+ *  - the corresponding floating-point value.\n+ *\n+ * The traits type defines:\n+ *  - the integer storage type used for quantization,\n+ *  - the static conversion functions \\c fromFloat() and \\c toFloat(), and\n+ *  - optional metadata such as value ranges.\n+ *\n+ * Quantized provides convenient constructors and assignment operators from\n+ * either representation, as well as comparison and string formatting utilities.\n+ */\n+\n+/**\n+ * \\typedef Quantized::TraitsType\n+ * \\brief The traits policy type defining the quantization behaviour\n+ *\n+ * Exposes the associated traits type used by this Quantized instance.\n+ * This allows external code to refer to constants or metadata defined in\n+ * the traits, such as \\c TraitsType::min or \\c TraitsType::max.\n+ */\n+\n+/**\n+ * \\typedef Quantized::QuantizedType\n+ * \\brief The integer type used for the quantized representation\n+ *\n+ * This alias corresponds to \\c TraitsType::QuantizedType, as defined by\n+ * the traits class.\n+ */\n+\n+/**\n+ * \\fn Quantized::Quantized(float x)\n+ * \\brief Construct a Quantized value from a floating-point number\n+ * \\param[in] x The floating-point value to be quantized\n+ *\n+ * Converts the floating-point input \\a x to its quantized integer\n+ * representation using the associated traits policy, and initializes\n+ * both the quantized and floating-point members.\n+ */\n+\n+/**\n+ * \\fn Quantized::Quantized(QuantizedType x)\n+ * \\brief Construct a Quantized value from an existing quantized integer\n+ * \\param[in] x The quantized integer value\n+ *\n+ * Converts the quantized integer \\a x to its corresponding floating-point\n+ * value using the traits policy, and initializes both internal members.\n+ */\n+\n+/**\n+ * \\fn Quantized::operator=(float x)\n+ * \\brief Assign a floating-point value to the Quantized object\n+ * \\param[in] x The floating-point value to assign\n+ * \\return A reference to the updated Quantized object\n+ *\n+ * Converts the floating-point value \\a x to its quantized integer\n+ * representation using the traits policy and updates both members.\n+ */\n+\n+/**\n+ * \\fn Quantized::operator=(QuantizedType x)\n+ * \\brief Assign a quantized integer value to the Quantized object\n+ * \\param[in] x The quantized integer value to assign\n+ * \\return A reference to the updated Quantized object\n+ *\n+ * Converts the quantized integer \\a x to its corresponding floating-point\n+ * value using the traits policy and updates both members.\n+ */\n+\n+/**\n+ * \\fn Quantized::value() const noexcept\n+ * \\brief Retrieve the floating-point representation\n+ * \\return The floating-point value corresponding to the quantized value\n+ */\n+\n+/**\n+ * \\fn Quantized::quantized() const noexcept\n+ * \\brief Retrieve the quantized integer representation\n+ * \\return The quantized integer value\n+ */\n+\n+/**\n+ * \\fn Quantized::toString() const\n+ * \\brief Format the quantized and floating-point values as a string\n+ * \\return A string containing the hexadecimal quantized value and its\n+ *         floating-point equivalent.\n+ */\n+\n+/**\n+ * \\fn Quantized::operator==(const Quantized &other) const noexcept\n+ * \\brief Compare two Quantized objects for equality\n+ * \\param[in] other The other Quantized object to compare against\n+ * \\return True if both objects have the same quantized integer value\n+ */\n+\n+/**\n+ * \\fn Quantized::operator!=(const Quantized &other) const noexcept\n+ * \\brief Compare two Quantized objects for inequality\n+ * \\param[in] other The other Quantized object to compare against\n+ * \\return True if the quantized integer values differ\n+ */\n+\n+/**\n+ * \\fn std::ostream &Quantized::operator<<(std::ostream &out, const Quantized<Traits> &q)\n+ * \\brief Insert a text representation of a Quantized into an output stream\n+ * \\param[in] out The output stream\n+ * \\param[in] q The Quantized\n+ * \\return The output stream \\a out\n+ */\n+\n+} /* namespace ipa */\n+\n+} /* namespace libcamera */\ndiff --git a/src/ipa/libipa/quantized.h b/src/ipa/libipa/quantized.h\nnew file mode 100644\nindex 000000000000..045ccb755a85\n--- /dev/null\n+++ b/src/ipa/libipa/quantized.h\n@@ -0,0 +1,83 @@\n+/* SPDX-License-Identifier: LGPL-2.1-or-later */\n+/*\n+ * Copyright (C) 2025, Ideas On Board Oy\n+ *\n+ * Helper class to manage conversions between floating point types and quantized\n+ * storage and representation of those values.\n+ */\n+\n+#pragma once\n+\n+#include <sstream>\n+#include <type_traits>\n+\n+#include <libcamera/base/utils.h>\n+\n+namespace libcamera {\n+\n+namespace ipa {\n+\n+template<typename Traits>\n+struct Quantized {\n+\tusing TraitsType = Traits;\n+\tusing QuantizedType = typename Traits::QuantizedType;\n+\tstatic_assert(std::is_arithmetic_v<QuantizedType>,\n+\t\t      \"Quantized: QuantizedType must be arithmetic\");\n+\n+\tQuantized()\n+\t\t: Quantized(0.0f) {}\n+\tQuantized(float x) { *this = x; }\n+\tQuantized(QuantizedType x) { *this = x; }\n+\n+\tQuantized &operator=(float x)\n+\t{\n+\t\tquantized_ = Traits::fromFloat(x);\n+\t\tvalue_ = Traits::toFloat(quantized_);\n+\t\treturn *this;\n+\t}\n+\n+\tQuantized &operator=(QuantizedType x)\n+\t{\n+\t\tvalue_ = Traits::toFloat(x);\n+\t\tquantized_ = x;\n+\t\treturn *this;\n+\t}\n+\n+\tfloat value() const noexcept { return value_; }\n+\tQuantizedType quantized() const noexcept { return quantized_; }\n+\n+\tstd::string toString() const\n+\t{\n+\t\tstd::stringstream ss;\n+\t\tss << *this;\n+\n+\t\treturn ss.str();\n+\t}\n+\n+\tbool operator==(const Quantized &other) const noexcept\n+\t{\n+\t\treturn quantized_ == other.quantized_;\n+\t}\n+\n+\tbool operator!=(const Quantized &other) const noexcept\n+\t{\n+\t\treturn !(*this == other);\n+\t}\n+\n+\tfriend std::ostream &operator<<(std::ostream &out,\n+\t\t\t\t\tconst Quantized<Traits> &q)\n+\t{\n+\t\tout << \"[\" << utils::hex(q.quantized())\n+\t\t    << \":\" << q.value() << \"]\";\n+\n+\t\treturn out;\n+\t}\n+\n+private:\n+\tQuantizedType quantized_;\n+\tfloat value_;\n+};\n+\n+} /* namespace ipa */\n+\n+} /* namespace libcamera */\n",
    "prefixes": [
        "v5",
        "01/16"
    ]
}