1 /*
2  *  Copyright (c) 2013 The WebM project authors. All Rights Reserved.
3  *
4  *  Use of this source code is governed by a BSD-style license
5  *  that can be found in the LICENSE file in the root of the source
6  *  tree. An additional intellectual property rights grant can be found
7  *  in the file PATENTS.  All contributing project authors may
8  *  be found in the AUTHORS file in the root of the source tree.
9  */
10 
11 #ifndef VPX_VP9_COMMON_VP9_SCAN_H_
12 #define VPX_VP9_COMMON_VP9_SCAN_H_
13 
14 #include "vpx/vpx_integer.h"
15 #include "vpx_ports/mem.h"
16 
17 #include "vp9/common/vp9_enums.h"
18 #include "vp9/common/vp9_blockd.h"
19 
20 #ifdef __cplusplus
21 extern "C" {
22 #endif
23 
24 #define MAX_NEIGHBORS 2
25 
26 typedef struct {
27   const int16_t *scan;
28   const int16_t *iscan;
29   const int16_t *neighbors;
30 } scan_order;
31 
32 extern const scan_order vp9_default_scan_orders[TX_SIZES];
33 extern const scan_order vp9_scan_orders[TX_SIZES][TX_TYPES];
34 
get_coef_context(const int16_t * neighbors,const uint8_t * token_cache,int c)35 static INLINE int get_coef_context(const int16_t *neighbors,
36                                    const uint8_t *token_cache, int c) {
37   return (1 + token_cache[neighbors[MAX_NEIGHBORS * c + 0]] +
38           token_cache[neighbors[MAX_NEIGHBORS * c + 1]]) >>
39          1;
40 }
41 
get_scan(const MACROBLOCKD * xd,TX_SIZE tx_size,PLANE_TYPE type,int block_idx)42 static INLINE const scan_order *get_scan(const MACROBLOCKD *xd, TX_SIZE tx_size,
43                                          PLANE_TYPE type, int block_idx) {
44   const MODE_INFO *const mi = xd->mi[0];
45 
46   if (is_inter_block(mi) || type != PLANE_TYPE_Y || xd->lossless) {
47     return &vp9_default_scan_orders[tx_size];
48   } else {
49     const PREDICTION_MODE mode = get_y_mode(mi, block_idx);
50     return &vp9_scan_orders[tx_size][intra_mode_to_tx_type_lookup[mode]];
51   }
52 }
53 
54 #ifdef __cplusplus
55 }  // extern "C"
56 #endif
57 
58 #endif  // VPX_VP9_COMMON_VP9_SCAN_H_
59