diff -r 8eb799bf1d39 -r 25a11859975b streamlet-examples/qr.cpp
--- a/streamlet-examples/qr.cpp	Sat Apr 24 20:22:59 2021 +0200
+++ /dev/null	Thu Jan 01 00:00:00 1970 +0000
@@ -1,187 +0,0 @@
-/**
- * Relational pipes
- * Copyright © 2020 František Kučera (Frantovo.cz, GlobalCode.info)
- *
- * This program is free software: you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation, version 3 of the License.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program. If not, see <http://www.gnu.org/licenses/>.
- */
-
-#include <unistd.h>
-
-#include <Magick++.h>
-#include <zbar.h>
-
-#include <relpipe/xmlwriter/XMLWriter.h>
-
-#include "streamlet-common.h"
-
-/**
- * This streamlet extracts QR codes from image files.
- * 
- * It provides three attributes:
- *  - qr: first QR code found (if any)
- *  - qr_count: number of QR codes found
- *  - qr_xml: XML containing all QR cpdes found an additional metadata
- *	
- */
-class QRStreamlet : public Streamlet {
-private:
-
-	const wstring XMLNS = L"tag:globalcode.info,2018:qr:FIXME:final-xmlns"; // FIXME: correct xmlns URI
-
-	class Point {
-	public:
-		int x;
-		int y;
-	};
-
-	class Symbol {
-	public:
-		int id;
-		std::wstring value;
-		std::wstring type;
-		int x;
-		int y;
-		int width;
-		int height;
-		std::vector<Point> polygon;
-	};
-
-	std::vector<Symbol> findSymbols(std::wstring fileName) {
-		std::vector<Symbol> result;
-
-		Magick::Image magick(toBytes(fileName));
-		int width = magick.columns();
-		int height = magick.rows();
-		Magick::Blob blob;
-		magick.modifyImage();
-		magick.write(&blob, "GRAY", 8);
-		const void *raw = blob.data();
-
-		zbar::Image image(width, height, "Y800", raw, width * height);
-		zbar::ImageScanner scanner;
-
-		scanner.scan(image);
-
-		int id = 0;
-		for (zbar::Image::SymbolIterator symbol = image.symbol_begin(); symbol != image.symbol_end(); ++symbol, id++) {
-			Symbol s;
-
-
-			s.id = id;
-			s.type = fromBytes(symbol->get_type_name());
-			s.value = fromBytes(symbol->get_data());
-
-			int minX = 0;
-			int minY = 0;
-			int maxX = 0;
-			int maxY = 0;
-
-			// TODO: return original polygon in XML
-			for (int i = 0, locationSize = symbol->get_location_size(); i < locationSize; i++) {
-				int x = symbol->get_location_x(i);
-				int y = symbol->get_location_y(i);
-				minX = minX ? std::min(minX, x) : x;
-				minY = minY ? std::min(minY, y) : y;
-				maxX = std::max(maxX, x);
-				maxY = std::max(maxY, y);
-				s.polygon.push_back({x, y});
-			}
-
-			s.x = minX;
-			s.y = minY;
-			s.width = maxX - minX;
-			s.height = maxY - minY;
-
-			result.push_back(s);
-		}
-
-
-
-		return result;
-	}
-
-protected:
-
-	std::vector<AttributeMetadata> getOutputAttributesMetadata() override {
-		std::vector<AttributeMetadata> oam;
-		int i = 0;
-		oam.push_back({getAlias(i++, L"qr"), STRING});
-		oam.push_back({getAlias(i++, L"qr_count"), INTEGER});
-		oam.push_back({getAlias(i++, L"qr_xml"), STRING});
-		return oam;
-	}
-
-	std::vector<OutputAttribute> getOutputAttributes() override {
-		bool validInput = false;
-		bool hasSymbols = false;
-		std::wstring first;
-		std::stringstream xml;
-
-		std::vector<Symbol> symbols;
-		try {
-			symbols = findSymbols(getCurrentFile());
-			validInput = true;
-		} catch (...) {
-			// just ignore the errors;
-			// the file is probably not an image or we do not have read permissions
-			validInput = false;
-		}
-
-		for (Symbol s : symbols) {
-			// TODO: match against pattern (if any)
-			first = s.value;
-			hasSymbols = true;
-			break;
-		}
-
-		relpipe::xmlwriter::XMLWriter xmlWriter(xml);
-		xmlWriter.writeStartElement(L"qr",{L"xmlns", XMLNS});
-
-		// TODO: common metadata
-		// xmlWriter.writeStartElement(L"source");
-		// xmlWriter.writeTextElement(L"height",{}, std::to_wstring(...));
-		// xmlWriter.writeTextElement(L"width",{}, std::to_wstring(...));
-		// xmlWriter.writeEndElement();
-
-		for (Symbol s : symbols) {
-			xmlWriter.writeStartElement(L"symbol");
-			xmlWriter.writeTextElement(L"value",{}, s.value);
-			
-			// TODO: well-designed XML schema
-			// TODO: synchronize/share common XML parts with relpipe-in-qr
-			xmlWriter.writeStartElement(L"rectangular-box");
-			xmlWriter.writeTextElement(L"x",{}, std::to_wstring(s.x));
-			xmlWriter.writeTextElement(L"y",{}, std::to_wstring(s.y));
-			xmlWriter.writeTextElement(L"height",{}, std::to_wstring(s.height));
-			xmlWriter.writeTextElement(L"width",{}, std::to_wstring(s.width));
-			xmlWriter.writeEndElement();
-
-			xmlWriter.writeStartElement(L"polygon");
-			for (Point p : s.polygon) xmlWriter.writeEmptyElement(L"point",{L"x", std::to_wstring(p.x), L"y", std::to_wstring(p.y)});
-			xmlWriter.writeEndElement();
-
-			xmlWriter.writeEndElement();
-		}
-
-		xmlWriter.writeEndElement();
-
-		std::vector<OutputAttribute> oa;
-		// TODO: report also validInput (distinguish it from hasSymbols)
-		oa.push_back({first, !hasSymbols});
-		oa.push_back({std::to_wstring(symbols.size()), false});
-		oa.push_back({fromBytes(xml.str()), false});
-		return oa;
-	}
-};
-
-STREAMLET_RUN(QRStreamlet)