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-rw-r--r--media/ffvpx/libavcodec/unary.h69
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diff --git a/media/ffvpx/libavcodec/unary.h b/media/ffvpx/libavcodec/unary.h
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+/*
+ * copyright (c) 2004 Michael Niedermayer <michaelni@gmx.at>
+ *
+ * This file is part of FFmpeg.
+ *
+ * FFmpeg is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * FFmpeg 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
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with FFmpeg; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#ifndef AVCODEC_UNARY_H
+#define AVCODEC_UNARY_H
+
+#include "get_bits.h"
+
+/**
+ * Get unary code of limited length
+ * @param gb GetBitContext
+ * @param[in] stop The bitstop value (unary code of 1's or 0's)
+ * @param[in] len Maximum length
+ * @return unary 0 based code index. This is also the length in bits of the
+ * code excluding the stop bit.
+ * (in case len=1)
+ * 1 0
+ * 0 1
+ * (in case len=2)
+ * 1 0
+ * 01 1
+ * 00 2
+ * (in case len=3)
+ * 1 0
+ * 01 1
+ * 001 2
+ * 000 3
+ */
+static inline int get_unary(GetBitContext *gb, int stop, int len)
+{
+ int i;
+
+ for(i = 0; i < len && get_bits1(gb) != stop; i++);
+ return i;
+}
+
+/**
+ * Get unary code terminated by a 0 with a maximum length of 33
+ * @param gb GetBitContext
+ * @return Unary length/index
+ */
+static inline int get_unary_0_33(GetBitContext *gb)
+{
+ return get_unary(gb, 0, 33);
+}
+
+static inline int get_unary_0_9(GetBitContext *gb)
+{
+ return get_unary(gb, 0, 9);
+}
+
+#endif /* AVCODEC_UNARY_H */