FFmpeg  3.4.9
hevcdsp.c
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1 /*
2  * SIMD-optimized IDCT functions for HEVC decoding
3  * Copyright (c) Alexandra Hajkova
4  *
5  * This file is part of FFmpeg.
6  *
7  * FFmpeg is free software; you can redistribute it and/or
8  * modify it under the terms of the GNU Lesser General Public
9  * License as published by the Free Software Foundation; either
10  * version 2.1 of the License, or (at your option) any later version.
11  *
12  * FFmpeg is distributed in the hope that it will be useful,
13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15  * Lesser General Public License for more details.
16  *
17  * You should have received a copy of the GNU Lesser General Public
18  * License along with FFmpeg; if not, write to the Free Software
19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20  */
21 
22 #include "config.h"
23 
24 #include "libavutil/attributes.h"
25 #include "libavutil/cpu.h"
26 #include "libavutil/ppc/cpu.h"
28 
29 #include "libavcodec/hevcdsp.h"
30 
31 #if HAVE_ALTIVEC
32 static const vec_s16 trans4[4] = {
33  { 64, 64, 64, 64, 64, 64, 64, 64 },
34  { 83, 36, 83, 36, 83, 36, 83, 36 },
35  { 64, -64, 64, -64, 64, -64, 64, -64 },
36  { 36, -83, 36, -83, 36, -83, 36, -83 },
37 };
38 
39 static const vec_u8 mask[2] = {
40  { 0x00, 0x01, 0x08, 0x09, 0x10, 0x11, 0x18, 0x19, 0x02, 0x03, 0x0A, 0x0B, 0x12, 0x13, 0x1A, 0x1B },
41  { 0x04, 0x05, 0x0C, 0x0D, 0x14, 0x15, 0x1C, 0x1D, 0x06, 0x07, 0x0E, 0x0F, 0x16, 0x17, 0x1E, 0x1F },
42 };
43 
44 static void transform4x4(vec_s16 src_01, vec_s16 src_23, vec_s32 res[4],
45  const int shift, int16_t *coeffs)
46 {
47  vec_s16 src_02, src_13;
48  vec_s32 zero = vec_splat_s32(0);
49  vec_s32 e0, o0, e1, o1;
50  vec_s32 add;
51 
52  src_13 = vec_mergel(src_01, src_23);
53  src_02 = vec_mergeh(src_01, src_23);
54 
55  e0 = vec_msums(src_02, trans4[0], zero);
56  o0 = vec_msums(src_13, trans4[1], zero);
57  e1 = vec_msums(src_02, trans4[2], zero);
58  o1 = vec_msums(src_13, trans4[3], zero);
59 
60  switch(shift) {
61  case 7: add = vec_sl(vec_splat_s32(1), vec_splat_u32( 7 - 1)); break;
62  case 10: add = vec_sl(vec_splat_s32(1), vec_splat_u32(10 - 1)); break;
63  case 12: add = vec_sl(vec_splat_s32(1), vec_splat_u32(12 - 1)); break;
64  default: abort();
65  }
66 
67  e0 = vec_add(e0, add);
68  e1 = vec_add(e1, add);
69 
70  res[0] = vec_add(e0, o0);
71  res[1] = vec_add(e1, o1);
72  res[2] = vec_sub(e1, o1);
73  res[3] = vec_sub(e0, o0);
74 }
75 
76 static void scale(vec_s32 res[4], vec_s16 res_packed[2], int shift)
77 {
78  int i;
79  vec_u32 v_shift;
80 
81  switch(shift) {
82  case 7: v_shift = vec_splat_u32(7) ; break;
83  case 10: v_shift = vec_splat_u32(10); break;
84  case 12: v_shift = vec_splat_u32(12); break;
85  default: abort();
86  }
87 
88  for (i = 0; i < 4; i++)
89  res[i] = vec_sra(res[i], v_shift);
90 
91  // clip16
92  res_packed[0] = vec_packs(res[0], res[1]);
93  res_packed[1] = vec_packs(res[2], res[3]);
94 }
95 
96 #define FUNCDECL(a, depth) a ## _ ## depth ## _altivec
97 #define FUNC(a, b) FUNCDECL(a, b)
98 
99 #define BIT_DEPTH 8
100 #include "hevcdsp_template.c"
101 #undef BIT_DEPTH
102 
103 #define BIT_DEPTH 10
104 #include "hevcdsp_template.c"
105 #undef BIT_DEPTH
106 #endif /* HAVE_ALTIVEC */
107 
109 {
110 #if HAVE_ALTIVEC
112  return;
113 
114  if (bit_depth == 8)
115  c->idct[0] = ff_hevc_idct_4x4_8_altivec;
116  if (bit_depth == 10)
117  c->idct[0] = ff_hevc_idct_4x4_10_altivec;
118 #endif /* HAVE_ALTIVEC */
119 }
static int shift(int a, int b)
Definition: sonic.c:82
#define vec_s32
Definition: util_altivec.h:43
Macro definitions for various function/variable attributes.
void(* idct[4])(int16_t *coeffs, int col_limit)
Definition: hevcdsp.h:57
#define av_cold
Definition: attributes.h:82
#define vec_s16
Definition: util_altivec.h:41
static const uint16_t mask[17]
Definition: lzw.c:38
#define PPC_ALTIVEC(flags)
Definition: cpu.h:26
#define zero
Definition: regdef.h:64
static void bit_depth(AudioStatsContext *s, uint64_t mask, uint64_t imask, AVRational *depth)
Definition: af_astats.c:152
#define vec_u8
Definition: util_altivec.h:38
#define vec_u32
Definition: util_altivec.h:42
int av_get_cpu_flags(void)
Return the flags which specify extensions supported by the CPU.
Definition: cpu.c:92
av_cold void ff_hevc_dsp_init_ppc(HEVCDSPContext *c, const int bit_depth)
Definition: hevcdsp.c:108
Contains misc utility macros and inline functions.
static double c[64]
static const int16_t coeffs[]