Initial commit

image/codecs/indeo/get_bits.h

@@ -0,0 +1,89 @@
+/* ScummVM - Graphic Adventure Engine
+ *
+ * ScummVM is the legal property of its developers, whose names
+ * are too numerous to list here. Please refer to the COPYRIGHT
+ * file distributed with this source distribution.
+ *
+ * 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, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * 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/>.
+ *
+ */
+
+#ifndef IMAGE_CODECS_INDEO_GET_BITS_H
+#define IMAGE_CODECS_INDEO_GET_BITS_H
+
+#include "common/bitstream.h"
+
+namespace Image {
+namespace Indeo {
+
+/**
+ * Intel Indeo Bitstream reader
+ */
+class GetBits : public Common::BitStreamMemory8LSB {
+public:
+	/**
+	* Constructor
+	*/
+	GetBits(const byte *dataPtr, uint32 dataSize) : Common::BitStreamMemory8LSB(new Common::BitStreamMemoryStream(dataPtr, dataSize), DisposeAfterUse::YES) {}
+
+	/**
+	 * The number of bits left
+	 */
+	int getBitsLeft() const { return size() - pos(); }
+
+	/**
+	 * Parse a VLC code.
+	 * @param bits is the number of bits which will be read at once, must be
+	 *             identical to nbBits in init_vlc()
+	 * @param maxDepth is the number of times bits bits must be read to completely
+	 *                  read the longest vlc code
+	 *                  = (max_vlc_length + bits - 1) / bits
+	 */
+	template <int maxDepth, int bits>
+	int getVLC2(int16 (*table)[2]) {
+		int code;
+		int n, nbBits;
+		unsigned int index;
+
+		index = peekBits<bits>();
+		code  = table[index][0];
+		n     = table[index][1];
+
+		if (maxDepth > 1 && n < 0) {
+			skip(bits);
+			nbBits = -n;
+
+			index = peekBits(nbBits) + code;
+			code = table[index][0];
+			n = table[index][1];
+
+			if (maxDepth > 2 && n < 0) {
+				skip(nbBits);
+				nbBits = -n;
+
+				index = peekBits(nbBits) + code;
+				code = table[index][0];
+				n = table[index][1];
+			}
+		}
+
+		skip(n);
+		return code;
+	}
+};
+
+} // End of namespace Indeo
+} // End of namespace Image
+
+#endif