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authorRĂ©mi Verschelde <rverschelde@gmail.com>2016-10-30 18:12:00 +0100
committerGitHub <noreply@github.com>2016-10-30 18:12:00 +0100
commitc6c13eb8fc7d4ad631a92edcf360f38210129d39 (patch)
tree12e82cb0ab3e2c3953d92ffd2aca5500685b87d7 /thirdparty/libvpx/vp8/common/treecoder.h
parent1944635ac4f3e9f12b176c2f38d43205195c35c5 (diff)
parentd710b265f8c9c94f3315d2d2ae2267c7437eb179 (diff)
Merge pull request #6490 from zaps166/webm-pr
Add WebM support
Diffstat (limited to 'thirdparty/libvpx/vp8/common/treecoder.h')
-rw-r--r--thirdparty/libvpx/vp8/common/treecoder.h98
1 files changed, 98 insertions, 0 deletions
diff --git a/thirdparty/libvpx/vp8/common/treecoder.h b/thirdparty/libvpx/vp8/common/treecoder.h
new file mode 100644
index 0000000000..d22b7c570c
--- /dev/null
+++ b/thirdparty/libvpx/vp8/common/treecoder.h
@@ -0,0 +1,98 @@
+/*
+ * Copyright (c) 2010 The WebM project authors. All Rights Reserved.
+ *
+ * Use of this source code is governed by a BSD-style license
+ * that can be found in the LICENSE file in the root of the source
+ * tree. An additional intellectual property rights grant can be found
+ * in the file PATENTS. All contributing project authors may
+ * be found in the AUTHORS file in the root of the source tree.
+ */
+
+
+#ifndef VP8_COMMON_TREECODER_H_
+#define VP8_COMMON_TREECODER_H_
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+typedef unsigned char vp8bc_index_t; /* probability index */
+
+
+typedef unsigned char vp8_prob;
+
+#define vp8_prob_half ( (vp8_prob) 128)
+
+typedef signed char vp8_tree_index;
+struct bool_coder_spec;
+
+typedef struct bool_coder_spec bool_coder_spec;
+typedef struct bool_writer bool_writer;
+typedef struct bool_reader bool_reader;
+
+typedef const bool_coder_spec c_bool_coder_spec;
+typedef const bool_writer c_bool_writer;
+typedef const bool_reader c_bool_reader;
+
+
+
+# define vp8_complement( x) (255 - x)
+
+
+/* We build coding trees compactly in arrays.
+ Each node of the tree is a pair of vp8_tree_indices.
+ Array index often references a corresponding probability table.
+ Index <= 0 means done encoding/decoding and value = -Index,
+ Index > 0 means need another bit, specification at index.
+ Nonnegative indices are always even; processing begins at node 0. */
+
+typedef const vp8_tree_index vp8_tree[], *vp8_tree_p;
+
+
+typedef const struct vp8_token_struct
+{
+ int value;
+ int Len;
+} vp8_token;
+
+/* Construct encoding array from tree. */
+
+void vp8_tokens_from_tree(struct vp8_token_struct *, vp8_tree);
+void vp8_tokens_from_tree_offset(struct vp8_token_struct *, vp8_tree,
+ int offset);
+
+
+/* Convert array of token occurrence counts into a table of probabilities
+ for the associated binary encoding tree. Also writes count of branches
+ taken for each node on the tree; this facilitiates decisions as to
+ probability updates. */
+
+void vp8_tree_probs_from_distribution(
+ int n, /* n = size of alphabet */
+ vp8_token tok [ /* n */ ],
+ vp8_tree tree,
+ vp8_prob probs [ /* n-1 */ ],
+ unsigned int branch_ct [ /* n-1 */ ] [2],
+ const unsigned int num_events[ /* n */ ],
+ unsigned int Pfactor,
+ int Round
+);
+
+/* Variant of above using coder spec rather than hardwired 8-bit probs. */
+
+void vp8bc_tree_probs_from_distribution(
+ int n, /* n = size of alphabet */
+ vp8_token tok [ /* n */ ],
+ vp8_tree tree,
+ vp8_prob probs [ /* n-1 */ ],
+ unsigned int branch_ct [ /* n-1 */ ] [2],
+ const unsigned int num_events[ /* n */ ],
+ c_bool_coder_spec *s
+);
+
+
+#ifdef __cplusplus
+} // extern "C"
+#endif
+
+#endif // VP8_COMMON_TREECODER_H_