added resizer

lib/danbooru_image_resizer/RowBuffer.h

@@ -0,0 +1,40 @@
+#ifndef ROW_BUFFER_H
+#define ROW_BUFFER_H
+
+#include <stdint.h>
+
+class RowBuffer
+{
+public:
+	RowBuffer();
+	~RowBuffer();
+
+	bool Init(int Width, int Height, int BPP);
+
+	/* Return row, allocating if necessary. */
+	uint8_t *GetRow(int row);
+
+	// Free rows [0,DiscardRow).
+	void DiscardRows(int DiscardRow);
+
+	/* Get a range of rows allocated in m_Rows: [m_StartRow,m_EndRow).  If
+	 * more than one allocated range exists, which range is returned is undefined. */
+	int GetStartRow() const { return m_StartRow; }
+	int GetEndRow() const { return m_EndRow; }
+	const uint8_t *const *GetRows() const { return m_Rows; }
+
+private:
+	/* Array of image rows.  These are allocated as needed. */
+	uint8_t **m_Rows;
+
+	/*  in m_Rows is allocated: */
+	int m_StartRow;
+	int m_EndRow;
+
+	int m_Width;
+	int m_Height;
+	int m_BPP;
+};
+
+#endif
+