avcodec/golomb: Factor writing golomb codes out

Most users only want to either read or write golomb codes, not both.
By splitting these headers one avoids having unnecesssary
(get|put)_hits.h inclusions.

Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>

1 files changed, 168 insertions, 0 deletions

diff --git a/libavcodec/put_golomb.h b/libavcodec/put_golomb.h
new file mode 100644
index 0000000000..9ca911fc3c
--- /dev/null
+++ b/libavcodec/put_golomb.h
@@ -0,0 +1,168 @@
+/*
+ * exp golomb vlc writing stuff
+ * Copyright (c) 2003 Michael Niedermayer <michaelni@gmx.at>
+ * Copyright (c) 2004 Alex Beregszaszi
+ *
+ * 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
+ */
+
+/**
+ * @file
+ * @brief
+ *     exp golomb vlc writing stuff
+ * @author Michael Niedermayer <michaelni@gmx.at> and Alex Beregszaszi
+ */
+
+#ifndef AVCODEC_PUT_GOLOMB_H
+#define AVCODEC_PUT_GOLOMB_H
+
+#include <stdint.h>
+#include "put_bits.h"
+
+extern const uint8_t ff_ue_golomb_len[256];
+
+/**
+ * write unsigned exp golomb code. 2^16 - 2 at most
+ */
+static inline void set_ue_golomb(PutBitContext *pb, int i)
+{
+    av_assert2(i >= 0);
+    av_assert2(i <= 0xFFFE);
+
+    if (i < 256)
+        put_bits(pb, ff_ue_golomb_len[i], i + 1);
+    else {
+        int e = av_log2(i + 1);
+        put_bits(pb, 2 * e + 1, i + 1);
+    }
+}
+
+/**
+ * write unsigned exp golomb code. 2^32-2 at most.
+ */
+static inline void set_ue_golomb_long(PutBitContext *pb, uint32_t i)
+{
+    av_assert2(i <= (UINT32_MAX - 1));
+
+    if (i < 256)
+        put_bits(pb, ff_ue_golomb_len[i], i + 1);
+    else {
+        int e = av_log2(i + 1);
+        put_bits64(pb, 2 * e + 1, i + 1);
+    }
+}
+
+/**
+ * write truncated unsigned exp golomb code.
+ */
+static inline void set_te_golomb(PutBitContext *pb, int i, int range)
+{
+    av_assert2(range >= 1);
+    av_assert2(i <= range);
+
+    if (range == 2)
+        put_bits(pb, 1, i ^ 1);
+    else
+        set_ue_golomb(pb, i);
+}
+
+/**
+ * write signed exp golomb code. 16 bits at most.
+ */
+static inline void set_se_golomb(PutBitContext *pb, int i)
+{
+    i = 2 * i - 1;
+    if (i < 0)
+        i ^= -1;    //FIXME check if gcc does the right thing
+    set_ue_golomb(pb, i);
+}
+
+/**
+ * write unsigned golomb rice code (ffv1).
+ */
+static inline void set_ur_golomb(PutBitContext *pb, int i, int k, int limit,
+                                 int esc_len)
+{
+    int e;
+
+    av_assert2(i >= 0);
+
+    e = i >> k;
+    if (e < limit)
+        put_bits(pb, e + k + 1, (1 << k) + av_mod_uintp2(i, k));
+    else
+        put_bits(pb, limit + esc_len, i - limit + 1);
+}
+
+/**
+ * write unsigned golomb rice code (jpegls).
+ */
+static inline void set_ur_golomb_jpegls(PutBitContext *pb, int i, int k,
+                                        int limit, int esc_len)
+{
+    int e;
+
+    av_assert2(i >= 0);
+
+    e = (i >> k) + 1;
+    if (e < limit) {
+        while (e > 31) {
+            put_bits(pb, 31, 0);
+            e -= 31;
+        }
+        put_bits(pb, e, 1);
+        if (k)
+            put_sbits(pb, k, i);
+    } else {
+        while (limit > 31) {
+            put_bits(pb, 31, 0);
+            limit -= 31;
+        }
+        put_bits(pb, limit, 1);
+        put_bits(pb, esc_len, i - 1);
+    }
+}
+
+/**
+ * write signed golomb rice code (ffv1).
+ */
+static inline void set_sr_golomb(PutBitContext *pb, int i, int k, int limit,
+                                 int esc_len)
+{
+    int v;
+
+    v  = -2 * i - 1;
+    v ^= (v >> 31);
+
+    set_ur_golomb(pb, v, k, limit, esc_len);
+}
+
+/**
+ * write signed golomb rice code (flac).
+ */
+static inline void set_sr_golomb_flac(PutBitContext *pb, int i, int k,
+                                      int limit, int esc_len)
+{
+    int v;
+
+    v  = -2 * i - 1;
+    v ^= (v >> 31);
+
+    set_ur_golomb_jpegls(pb, v, k, limit, esc_len);
+}
+
+#endif /* AVCODEC_PUT_GOLOMB_H */