[RFC PATCH 6/6] libcamera: converter_dw100: Load and apply dewarp vertex maps

[Umang Jain]

Load the dewarp vertex maps for different configurations using the
LIBCAMERA_DEWARP_CONFIG_FILE environment variable.

In addition, provide a applyMappings(stream) API for converter_dw100, in
order to apply mappings for the given stream. Plumb it into rkisp1
pipeline handler, if the dewarper is being used.

\todo The parsing of dewarp configuration file is yet to be determined.
I've used the same parsing logic as made in previous attempts:
https://patchwork.libcamera.org/patch/17348/

Signed-off-by: Umang Jain <umang.jain at ideasonboard.com>
---
 .../internal/converter/converter_dw100.h      |   5 +
 src/libcamera/converter/converter_dw100.cpp   | 127 ++++++++++++++++++
 src/libcamera/pipeline/rkisp1/rkisp1.cpp      |   4 +
 3 files changed, 136 insertions(+)

diff --git a/include/libcamera/internal/converter/converter_dw100.h b/include/libcamera/internal/converter/converter_dw100.h
index dc41f365..a3062e84 100644
--- a/include/libcamera/internal/converter/converter_dw100.h
+++ b/include/libcamera/internal/converter/converter_dw100.h
@@ -19,6 +19,11 @@ class ConverterDW100 : public V4L2M2MConverter
 {
 public:
 	ConverterDW100(std::shared_ptr<MediaDevice> media);
+
+	int applyMappings(const Stream *stream);
+
+private:
+	int loadDewarpMaps();
 };
 
 } /* namespace libcamera */
diff --git a/src/libcamera/converter/converter_dw100.cpp b/src/libcamera/converter/converter_dw100.cpp
index 3061fc71..1a641779 100644
--- a/src/libcamera/converter/converter_dw100.cpp
+++ b/src/libcamera/converter/converter_dw100.cpp
@@ -7,12 +7,17 @@
 
 #include "libcamera/internal/converter/converter_dw100.h"
 
+#include <linux/dw100.h>
+
+#include <libcamera/base/file.h>
 #include <libcamera/base/log.h>
 
+#include <libcamera/stream.h>
 #include <libcamera/geometry.h>
 
 #include "libcamera/internal/media_device.h"
 #include "libcamera/internal/v4l2_videodevice.h"
+#include "libcamera/internal/yaml_parser.h"
 
 namespace libcamera {
 
@@ -32,6 +37,128 @@ LOG_DECLARE_CATEGORY(Converter)
 ConverterDW100::ConverterDW100(std::shared_ptr<MediaDevice> media)
 	: V4L2M2MConverter(media.get(), Feature::Crop)
 {
+	loadDewarpMaps();
+}
+
+int ConverterDW100::loadDewarpMaps()
+{
+	int ret;
+
+	char const *configFromEnv = utils::secure_getenv("LIBCAMERA_DEWARP_CONFIG_FILE");
+	if (!configFromEnv || *configFromEnv == '\0')
+		return 0;
+
+	LOG(Converter, Info) << "Parsing dewarp configuration file " << configFromEnv;
+
+	std::string filename = std::string(configFromEnv);
+	File file(filename);
+
+	if (!file.open(File::OpenModeFlag::ReadOnly)) {
+		ret = file.error();
+		LOG(Converter, Error) << "Failed to open configuration file "
+				      << filename << ": " << strerror(-ret);
+		return ret;
+	}
+
+	std::unique_ptr<libcamera::YamlObject> data = YamlParser::parse(file);
+	if (!data)
+		return -EINVAL;
+
+	if (!data->contains("mappings")) {
+		LOG(Converter, Error) << "Vertex mapping key missing";
+		return -EINVAL;
+	}
+
+	const YamlObject &mappings = (*data)["mappings"];
+	if (!mappings.isList() || mappings.size() == 0) {
+		LOG(Converter, Error) << "Invalid mappings entry";
+		return -EINVAL;
+	}
+
+	LOG(Converter, Debug) << "Parsing " << mappings.size() << " mappings";
+	mappings_.clear();
+	mappings_.reserve(mappings.size());
+
+	for (std::size_t i = 0; i < mappings.size(); i++) {
+		const YamlObject &mapping = mappings[i];
+		if (!mapping.isDictionary()) {
+			LOG(Converter, Error) << "Mapping is not a dictionary";
+			return -EINVAL;
+		}
+
+		if (!mapping.contains("input-resolution")) {
+			LOG(Converter, Error) << "Input resolution missing";
+			return -EINVAL;
+		}
+
+		if (!mapping.contains("output-resolution")) {
+			LOG(Converter, Error) << "Output resolution missing";
+			return -EINVAL;
+		}
+
+		if (!mapping.contains("mapping")) {
+			LOG(Converter, Error) << "Mapping table missing";
+			return -EINVAL;
+		}
+
+		const YamlObject &input_res = mapping["input-resolution"];
+		if (!input_res.isList() || input_res.size() != 2) {
+			LOG(Converter, Error) << "Incorrect input resolution";
+			return -EINVAL;
+		}
+
+		const YamlObject &output_res = mapping["output-resolution"];
+		if (!output_res.isList() || output_res.size() != 2) {
+			LOG(Converter, Error) << "Incorrect output resolution";
+			return -EINVAL;
+		}
+
+		const YamlObject &map = mapping["mapping"];
+		if (!map.isList() || map.size() == 0) {
+			LOG(Converter, Error) << "Incorrect mapping entries";
+			return -EINVAL;
+		}
+
+		Size input(input_res[0].get<uint32_t>(0), input_res[1].get<uint32_t>(0));
+		Size output(output_res[0].get<uint32_t>(0), output_res[1].get<uint32_t>(0));
+		const auto &mapVector = map.getList<uint32_t>().value_or(std::vector<uint32_t>{});
+
+		LOG(Converter, Debug)
+			<< "Input/Output mapping resolution " << input << " -> " << output;
+
+		mappings_.emplace_back(Mapping(input, output, mapVector));
+	}
+
+	return mappings.size();
+}
+
+/*
+ * \brief Apply
+ * \todo this is just a wrapper, trying to test waters
+ * \param[in] media The media device implementing the converter
+ */
+int ConverterDW100::applyMappings(const Stream *stream)
+{
+	const StreamConfiguration &config = stream->configuration();
+	ControlList ctrls;
+	int ret = 0;
+
+	for (const auto &map : mappings_) {
+		/* Currently DW100's input and output configuration are same. */
+		if (map.inputSize() == config.size &&
+		    map.outputSize() == config.size) {
+			auto value = Span<const int32_t>(reinterpret_cast<const int32_t *>(map.mapping()), map.size());
+
+			ControlValue c(value);
+			ctrls.set(V4L2_CID_DW100_DEWARPING_16x16_VERTEX_MAP, c);
+			ret = applyControls(stream, ctrls);
+
+			LOG(Converter, Debug) << "Dewarp mapping applied for " << config.toString();
+			break;
+		}
+	}
+
+       return ret;
 }
 
 } /* namespace libcamera */
diff --git a/src/libcamera/pipeline/rkisp1/rkisp1.cpp b/src/libcamera/pipeline/rkisp1/rkisp1.cpp
index 881e10e1..f102b364 100644
--- a/src/libcamera/pipeline/rkisp1/rkisp1.cpp
+++ b/src/libcamera/pipeline/rkisp1/rkisp1.cpp
@@ -1019,6 +1019,10 @@ int PipelineHandlerRkISP1::start(Camera *camera, [[maybe_unused]] const ControlL
 				LOG(RkISP1, Error) << "Failed to start dewarper";
 				return ret;
 			}
+
+			ret = dewarper_->applyMappings(&data->mainPathStream_);
+			if (ret)
+				LOG(RkISP1, Warning) << "Dewarper mapping couldn't be applied";
 		}
 	}
 
-- 
2.45.0