5 files changed, 125 insertions, 17 deletions

diff --git a/src/ipa/libipa/algorithm.cpp b/src/ipa/libipa/algorithm.cpp
index cce2ed62..2df91e5d 100644
--- a/src/ipa/libipa/algorithm.cpp
+++ b/src/ipa/libipa/algorithm.cpp
@@ -19,14 +19,17 @@ namespace ipa {
 /**
  * \class Algorithm
  * \brief The base class for all IPA algorithms
- * \tparam Context The type of shared IPA context
- * \tparam Config The type of the IPA configuration data
- * \tparam Params The type of the ISP specific parameters
- * \tparam Stats The type of the IPA statistics and ISP results
+ * \tparam Module The IPA module type for this class of algorithms
  *
- * The Algorithm class defines a standard interface for IPA algorithms. By
- * abstracting algorithms, it makes possible the implementation of generic code
- * to manage algorithms regardless of their specific type.
+ * The Algorithm class defines a standard interface for IPA algorithms
+ * compatible with the \a Module. By abstracting algorithms, it makes possible
+ * the implementation of generic code to manage algorithms regardless of their
+ * specific type.
+ *
+ * To specialize the Algorithm class template, an IPA module shall specialize
+ * the Module class template with module-specific context and configuration
+ * types, and pass the specialized Module class as the \a Module template
+ * argument.
  */
 
 /**
diff --git a/src/ipa/libipa/algorithm.h b/src/ipa/libipa/algorithm.h
index 032a05b5..fd2ffcfb 100644
--- a/src/ipa/libipa/algorithm.h
+++ b/src/ipa/libipa/algorithm.h
@@ -10,27 +10,26 @@ namespace libcamera {
 
 namespace ipa {
 
-template<typename Context, typename FrameContext, typename Config,
-	 typename Params, typename Stats>
+template<typename Module>
 class Algorithm
 {
 public:
 	virtual ~Algorithm() {}
 
-	virtual int configure([[maybe_unused]] Context &context,
-			      [[maybe_unused]] const Config &configInfo)
+	virtual int configure([[maybe_unused]] typename Module::Context &context,
+			      [[maybe_unused]] const typename Module::Config &configInfo)
 	{
 		return 0;
 	}
 
-	virtual void prepare([[maybe_unused]] Context &context,
-			     [[maybe_unused]] Params *params)
+	virtual void prepare([[maybe_unused]] typename Module::Context &context,
+			     [[maybe_unused]] typename Module::Params *params)
 	{
 	}
 
-	virtual void process([[maybe_unused]] Context &context,
-			     [[maybe_unused]] FrameContext *frameContext,
-			     [[maybe_unused]] const Stats *stats)
+	virtual void process([[maybe_unused]] typename Module::Context &context,
+			     [[maybe_unused]] typename Module::FrameContext *frameContext,
+			     [[maybe_unused]] const typename Module::Stats *stats)
 	{
 	}
 };
diff --git a/src/ipa/libipa/meson.build b/src/ipa/libipa/meson.build
index 161cc5a1..465cf7d6 100644
--- a/src/ipa/libipa/meson.build
+++ b/src/ipa/libipa/meson.build
@@ -3,13 +3,16 @@
 libipa_headers = files([
     'algorithm.h',
     'camera_sensor_helper.h',
-    'histogram.h'
+    'histogram.h',
+    'module.h',
 ])
 
 libipa_sources = files([
+    'algorithm.cpp',
     'camera_sensor_helper.cpp',
     'histogram.cpp',
     'libipa.cpp',
+    'module.cpp',
 ])
 
 libipa_includes = include_directories('..')
diff --git a/src/ipa/libipa/module.cpp b/src/ipa/libipa/module.cpp
new file mode 100644
index 00000000..5a6f49a8
--- /dev/null
+++ b/src/ipa/libipa/module.cpp
@@ -0,0 +1,73 @@
+/* SPDX-License-Identifier: LGPL-2.1-or-later */
+/*
+ * Copyright (C) 2022, Ideas On Board
+ *
+ * module.cpp - IPA Module
+ */
+
+#include "module.h"
+
+/**
+ * \file module.h
+ * \brief IPA Module common interface
+ */
+
+namespace libcamera {
+
+namespace ipa {
+
+/**
+ * \class Module
+ * \brief The base class for all IPA modules
+ * \tparam Context The type of the shared IPA context
+ * \tparam FrameContext The type of the frame context
+ * \tparam Config The type of the IPA configuration data
+ * \tparam Params The type of the ISP specific parameters
+ * \tparam Stats The type of the IPA statistics and ISP results
+ *
+ * The Module class template defines a standard internal interface between IPA
+ * modules and libipa.
+ *
+ * While IPA modules are platform-specific, many of their internal functions are
+ * conceptually similar, even if they take different types of platform-specifc
+ * parameters. For instance, IPA modules could share code that instantiates,
+ * initializes and run algorithms if it wasn't for the fact that the the format
+ * of ISP parameters or statistics passed to the related functions is
+ * device-dependent.
+ *
+ * To enable a shared implementation of those common tasks in libipa, the Module
+ * class template defines a standard internal interface between IPA modules and
+ * libipa. The template parameters specify the types of module-dependent data.
+ * IPA modules shall create a specialization of the Module class template in
+ * their namespace, and use it to specialize other classes of libipa, such as
+ * the Algorithm class.
+ */
+
+/**
+ * \typedef Module::Context
+ * \brief The type of the shared IPA context
+ */
+
+/**
+ * \typedef Module::FrameContext
+ * \brief The type of the frame context
+ */
+
+/**
+ * \typedef Module::Config
+ * \brief The type of the IPA configuration data
+ */
+
+/**
+ * \typedef Module::Params
+ * \brief The type of the ISP specific parameters
+ */
+
+/**
+ * \typedef Module::Stats
+ * \brief The type of the IPA statistics and ISP results
+ */
+
+} /* namespace ipa */
+
+} /* namespace libcamera */
diff --git a/src/ipa/libipa/module.h b/src/ipa/libipa/module.h
new file mode 100644
index 00000000..c4d77812
--- /dev/null
+++ b/src/ipa/libipa/module.h
@@ -0,0 +1,30 @@
+/* SPDX-License-Identifier: LGPL-2.1-or-later */
+/*
+ * Copyright (C) 2022, Ideas On Board
+ *
+ * module.h - IPA module
+ */
+
+#pragma once
+
+namespace libcamera {
+
+namespace ipa {
+
+template<typename _Context, typename _FrameContext, typename _Config,
+	 typename _Params, typename _Stats>
+class Module
+{
+public:
+	using Context = _Context;
+	using FrameContext = _FrameContext;
+	using Config = _Config;
+	using Params = _Params;
+	using Stats = _Stats;
+
+	virtual ~Module() {}
+};
+
+} /* namespace ipa */
+
+} /* namespace libcamera */