Function ReadCodeWords

czxing/src/main/cpp/zxing/src/pdf417/PDFReader.cpp:216–255

template<typename POINT>
std::vector<int> ReadCodeWords(BitMatrixCursor<POINT> topCur, SymbolInfo info)
{
	printf("rows: %d, cols: %d, rowHeight: %.1f, colWidth: %d, firstRow: %d, lastRow: %d, ecLevel: %d\n", info.nRows,
		   info.nCols, info.rowHeight, info.colWidth, info.firstRow, info.lastRow, info.ecLevel);
	auto print = [](CodeWord c [[maybe_unused]]) { printf("%4d.%d ", c.code, c.cluster); };

	auto rowSkip = topCur.right();
	if (info.firstRow > info.lastRow) {
		topCur.p += (info.height - 1) * rowSkip;
		rowSkip = -rowSkip;
		std::swap(info.firstRow, info.lastRow);
	}

	int maxColWidth = info.colWidth * 3 / 2;
	std::vector<int> codeWords(info.nRows * info.nCols, -1);
	for (int row = info.firstRow; row < std::min(info.nRows, info.lastRow + 1); ++row) {
		int cluster = (row % 3) * 3;
		auto cur = topCur.movedBy(int((row - info.firstRow + 0.5f) * info.rowHeight) * rowSkip);
		// skip start pattern
		cur.stepToEdge(8 + cur.isWhite(), maxColWidth);
		// read off left row indicator column
		auto cw [[maybe_unused]] = ReadCodeWord(cur, cluster);
		printf("%3dx%3d:%2d: ", int(cur.p.x), int(cur.p.y), Row(cw));
		print(cw);

		for (int col = 0; col < info.nCols && cur.isIn(); ++col) {
			auto cw = ReadCodeWord(cur, cluster);
			codeWords[row * info.nCols + col] = cw.code;
			print(cw);
		}

#ifdef PRINT_DEBUG
		print(ReadCodeWord(cur));
		printf("\n");
		fflush(stdout);
#endif
	}

	return codeWords;
}

// forward declaration from PDFScanningDecoder.cpp
DecoderResult DecodeCodewords(std::vector<int>& codewords, int ecLevel, const std::vector<int>& erasures);