libvpx: Add VP9 decoder.

source/libvpx/vp9/common/vp9_entropy.h

+/*
+ *  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 VP9_COMMON_VP9_ENTROPY_H_
+#define VP9_COMMON_VP9_ENTROPY_H_
+
+#include "vp9/common/vp9_treecoder.h"
+#include "vp9/common/vp9_blockd.h"
+#include "vp9/common/vp9_common.h"
+#include "vp9/common/vp9_coefupdateprobs.h"
+
+extern const int vp9_i8x8_block[4];
+
+/* Coefficient token alphabet */
+
+#define ZERO_TOKEN              0       /* 0         Extra Bits 0+0 */
+#define ONE_TOKEN               1       /* 1         Extra Bits 0+1 */
+#define TWO_TOKEN               2       /* 2         Extra Bits 0+1 */
+#define THREE_TOKEN             3       /* 3         Extra Bits 0+1 */
+#define FOUR_TOKEN              4       /* 4         Extra Bits 0+1 */
+#define DCT_VAL_CATEGORY1       5       /* 5-6       Extra Bits 1+1 */
+#define DCT_VAL_CATEGORY2       6       /* 7-10      Extra Bits 2+1 */
+#define DCT_VAL_CATEGORY3       7       /* 11-18     Extra Bits 3+1 */
+#define DCT_VAL_CATEGORY4       8       /* 19-34     Extra Bits 4+1 */
+#define DCT_VAL_CATEGORY5       9       /* 35-66     Extra Bits 5+1 */
+#define DCT_VAL_CATEGORY6       10      /* 67+       Extra Bits 13+1 */
+#define DCT_EOB_TOKEN           11      /* EOB       Extra Bits 0+0 */
+#define MAX_ENTROPY_TOKENS 12
+#define ENTROPY_NODES 11
+#define EOSB_TOKEN              127     /* Not signalled, encoder only */
+
+#define INTER_MODE_CONTEXTS     7
+
+extern const vp9_tree_index vp9_coef_tree[];
+
+extern struct vp9_token_struct vp9_coef_encodings[MAX_ENTROPY_TOKENS];
+
+typedef struct {
+  vp9_tree_p tree;
+  const vp9_prob *prob;
+  int Len;
+  int base_val;
+} vp9_extra_bit_struct;
+
+extern vp9_extra_bit_struct vp9_extra_bits[12];    /* indexed by token value */
+
+#define PROB_UPDATE_BASELINE_COST   7
+
+#define MAX_PROB                255
+#define DCT_MAX_VALUE           8192
+
+/* Coefficients are predicted via a 3-dimensional probability table. */
+
+/* Outside dimension.  0 = Y no DC, 1 = Y2, 2 = UV, 3 = Y with DC */
+#define BLOCK_TYPES 4
+
+#define BLOCK_TYPES_8X8 4
+
+#define BLOCK_TYPES_16X16 4
+
+/* Middle dimension is a coarsening of the coefficient's
+   position within the 4x4 DCT. */
+
+#define COEF_BANDS 8
+extern DECLARE_ALIGNED(16, const int, vp9_coef_bands[16]);
+extern DECLARE_ALIGNED(64, const int, vp9_coef_bands_8x8[64]);
+extern DECLARE_ALIGNED(16, const int, vp9_coef_bands_16x16[256]);
+
+/* Inside dimension is 3-valued measure of nearby complexity, that is,
+   the extent to which nearby coefficients are nonzero.  For the first
+   coefficient (DC, unless block type is 0), we look at the (already encoded)
+   blocks above and to the left of the current block.  The context index is
+   then the number (0,1,or 2) of these blocks having nonzero coefficients.
+   After decoding a coefficient, the measure is roughly the size of the
+   most recently decoded coefficient (0 for 0, 1 for 1, 2 for >1).
+   Note that the intuitive meaning of this measure changes as coefficients
+   are decoded, e.g., prior to the first token, a zero means that my neighbors
+   are empty while, after the first token, because of the use of end-of-block,
+   a zero means we just decoded a zero and hence guarantees that a non-zero
+   coefficient will appear later in this block.  However, this shift
+   in meaning is perfectly OK because our context depends also on the
+   coefficient band (and since zigzag positions 0, 1, and 2 are in
+   distinct bands). */
+
+/*# define DC_TOKEN_CONTEXTS        3*/ /* 00, 0!0, !0!0 */
+#define PREV_COEF_CONTEXTS       4
+
+#define SUBEXP_PARAM                4   /* Subexponential code parameter */
+#define MODULUS_PARAM               13  /* Modulus parameter */
+
+extern DECLARE_ALIGNED(16, const unsigned char, vp9_prev_token_class[MAX_ENTROPY_TOKENS]);
+
+struct VP9Common;
+void vp9_default_coef_probs(struct VP9Common *);
+extern DECLARE_ALIGNED(16, const int, vp9_default_zig_zag1d[16]);
+
+extern DECLARE_ALIGNED(16, const int, vp9_col_scan[16]);
+extern DECLARE_ALIGNED(16, const int, vp9_row_scan[16]);
+
+extern DECLARE_ALIGNED(64, const int, vp9_default_zig_zag1d_8x8[64]);
+void vp9_coef_tree_initialize(void);
+
+extern DECLARE_ALIGNED(16, const int, vp9_default_zig_zag1d_16x16[256]);
+void vp9_adapt_coef_probs(struct VP9Common *);
+
+#endif