src/third_party/libwebp/dsp/upsampling_neon.c

   1 // Copyright 2011 Google Inc. All Rights Reserved.
   2 //
   3 // Use of this source code is governed by a BSD-style license
   4 // that can be found in the COPYING file in the root of the source
   5 // tree. An additional intellectual property rights grant can be found
   6 // in the file PATENTS. All contributing project authors may
   7 // be found in the AUTHORS file in the root of the source tree.
   8 // -----------------------------------------------------------------------------
   9 //
  10 // NEON version of YUV to RGB upsampling functions.
  11 //
  12 // Author: mans@mansr.com (Mans Rullgard)
  13 // Based on SSE code by: somnath@google.com (Somnath Banerjee)
  14
  15 #include "./dsp.h"
  16
  17 #if defined(__cplusplus) || defined(c_plusplus)
  18 extern "C" {
  19 #endif
  20
  21 #if defined(WEBP_USE_NEON)
  22
  23 #include <assert.h>
  24 #include <arm_neon.h>
  25 #include <string.h>
  26 #include "./yuv.h"
  27
  28 #ifdef FANCY_UPSAMPLING
  29
  30 // Loads 9 pixels each from rows r1 and r2 and generates 16 pixels.
  31 #define UPSAMPLE_16PIXELS(r1, r2, out) {                                \
  32   uint8x8_t a = vld1_u8(r1);                                            \
  33   uint8x8_t b = vld1_u8(r1 + 1);                                        \
  34   uint8x8_t c = vld1_u8(r2);                                            \
  35   uint8x8_t d = vld1_u8(r2 + 1);                                        \
  36                                                                         \
  37   uint16x8_t al = vshll_n_u8(a, 1);                                     \
  38   uint16x8_t bl = vshll_n_u8(b, 1);                                     \
  39   uint16x8_t cl = vshll_n_u8(c, 1);                                     \
  40   uint16x8_t dl = vshll_n_u8(d, 1);                                     \
  41                                                                         \
  42   uint8x8_t diag1, diag2;                                               \
  43   uint16x8_t sl;                                                        \
  44                                                                         \
  45   /* a + b + c + d */                                                   \
  46   sl = vaddl_u8(a,  b);                                                 \
  47   sl = vaddw_u8(sl, c);                                                 \
  48   sl = vaddw_u8(sl, d);                                                 \
  49                                                                         \
  50   al = vaddq_u16(sl, al); /* 3a +  b +  c +  d */                       \
  51   bl = vaddq_u16(sl, bl); /*  a + 3b +  c +  d */                       \
  52                                                                         \
  53   al = vaddq_u16(al, dl); /* 3a +  b +  c + 3d */                       \
  54   bl = vaddq_u16(bl, cl); /*  a + 3b + 3c +  d */                       \
  55                                                                         \
  56   diag2 = vshrn_n_u16(al, 3);                                           \
  57   diag1 = vshrn_n_u16(bl, 3);                                           \
  58                                                                         \
  59   a = vrhadd_u8(a, diag1);                                              \
  60   b = vrhadd_u8(b, diag2);                                              \
  61   c = vrhadd_u8(c, diag2);                                              \
  62   d = vrhadd_u8(d, diag1);                                              \
  63                                                                         \
  64   {                                                                     \
  65     const uint8x8x2_t a_b = {{ a, b }};                                 \
  66     const uint8x8x2_t c_d = {{ c, d }};                                 \
  67     vst2_u8(out,      a_b);                                             \
  68     vst2_u8(out + 32, c_d);                                             \
  69   }                                                                     \
  70 }
  71
  72 // Turn the macro into a function for reducing code-size when non-critical
  73 static void Upsample16Pixels(const uint8_t *r1, const uint8_t *r2,
  74                              uint8_t *out) {
  75   UPSAMPLE_16PIXELS(r1, r2, out);
  76 }
  77
  78 #define UPSAMPLE_LAST_BLOCK(tb, bb, num_pixels, out) {                  \
  79   uint8_t r1[9], r2[9];                                                 \
  80   memcpy(r1, (tb), (num_pixels));                                       \
  81   memcpy(r2, (bb), (num_pixels));                                       \
  82   /* replicate last byte */                                             \
  83   memset(r1 + (num_pixels), r1[(num_pixels) - 1], 9 - (num_pixels));    \
  84   memset(r2 + (num_pixels), r2[(num_pixels) - 1], 9 - (num_pixels));    \
  85   Upsample16Pixels(r1, r2, out);                                        \
  86 }
  87
  88 #define CY  76283
  89 #define CVR 89858
  90 #define CUG 22014
  91 #define CVG 45773
  92 #define CUB 113618
  93
  94 static const int16_t coef[4] = { CVR / 4, CUG, CVG / 2, CUB / 4 };
  95
  96 #define CONVERT8(FMT, XSTEP, N, src_y, src_uv, out, cur_x) {            \
  97   int i;                                                                \
  98   for (i = 0; i < N; i += 8) {                                          \
  99     int off = ((cur_x) + i) * XSTEP;                                    \
 100     uint8x8_t y  = vld1_u8(src_y + (cur_x)  + i);                       \
 101     uint8x8_t u  = vld1_u8((src_uv) + i);                               \
 102     uint8x8_t v  = vld1_u8((src_uv) + i + 16);                          \
 103     int16x8_t yy = vreinterpretq_s16_u16(vsubl_u8(y, u16));             \
 104     int16x8_t uu = vreinterpretq_s16_u16(vsubl_u8(u, u128));            \
 105     int16x8_t vv = vreinterpretq_s16_u16(vsubl_u8(v, u128));            \
 106                                                                         \
 107     int16x8_t ud = vshlq_n_s16(uu, 1);                                  \
 108     int16x8_t vd = vshlq_n_s16(vv, 1);                                  \
 109                                                                         \
 110     int32x4_t vrl = vqdmlal_lane_s16(vshll_n_s16(vget_low_s16(vv), 1),  \
 111                                      vget_low_s16(vd),  cf16, 0);       \
 112     int32x4_t vrh = vqdmlal_lane_s16(vshll_n_s16(vget_high_s16(vv), 1), \
 113                                      vget_high_s16(vd), cf16, 0);       \
 114     int16x8_t vr = vcombine_s16(vrshrn_n_s32(vrl, 16),                  \
 115                                 vrshrn_n_s32(vrh, 16));                 \
 116                                                                         \
 117     int32x4_t vl = vmovl_s16(vget_low_s16(vv));                         \
 118     int32x4_t vh = vmovl_s16(vget_high_s16(vv));                        \
 119     int32x4_t ugl = vmlal_lane_s16(vl, vget_low_s16(uu),  cf16, 1);     \
 120     int32x4_t ugh = vmlal_lane_s16(vh, vget_high_s16(uu), cf16, 1);     \
 121     int32x4_t gcl = vqdmlal_lane_s16(ugl, vget_low_s16(vv),  cf16, 2);  \
 122     int32x4_t gch = vqdmlal_lane_s16(ugh, vget_high_s16(vv), cf16, 2);  \
 123     int16x8_t gc = vcombine_s16(vrshrn_n_s32(gcl, 16),                  \
 124                                 vrshrn_n_s32(gch, 16));                 \
 125                                                                         \
 126     int32x4_t ubl = vqdmlal_lane_s16(vshll_n_s16(vget_low_s16(uu), 1),  \
 127                                      vget_low_s16(ud),  cf16, 3);       \
 128     int32x4_t ubh = vqdmlal_lane_s16(vshll_n_s16(vget_high_s16(uu), 1), \
 129                                      vget_high_s16(ud), cf16, 3);       \
 130     int16x8_t ub = vcombine_s16(vrshrn_n_s32(ubl, 16),                  \
 131                                 vrshrn_n_s32(ubh, 16));                 \
 132                                                                         \
 133     int32x4_t rl = vaddl_s16(vget_low_s16(yy),  vget_low_s16(vr));      \
 134     int32x4_t rh = vaddl_s16(vget_high_s16(yy), vget_high_s16(vr));     \
 135     int32x4_t gl = vsubl_s16(vget_low_s16(yy),  vget_low_s16(gc));      \
 136     int32x4_t gh = vsubl_s16(vget_high_s16(yy), vget_high_s16(gc));     \
 137     int32x4_t bl = vaddl_s16(vget_low_s16(yy),  vget_low_s16(ub));      \
 138     int32x4_t bh = vaddl_s16(vget_high_s16(yy), vget_high_s16(ub));     \
 139                                                                         \
 140     rl = vmulq_lane_s32(rl, cf32, 0);                                   \
 141     rh = vmulq_lane_s32(rh, cf32, 0);                                   \
 142     gl = vmulq_lane_s32(gl, cf32, 0);                                   \
 143     gh = vmulq_lane_s32(gh, cf32, 0);                                   \
 144     bl = vmulq_lane_s32(bl, cf32, 0);                                   \
 145     bh = vmulq_lane_s32(bh, cf32, 0);                                   \
 146                                                                         \
 147     y = vqmovun_s16(vcombine_s16(vrshrn_n_s32(rl, 16),                  \
 148                                  vrshrn_n_s32(rh, 16)));                \
 149     u = vqmovun_s16(vcombine_s16(vrshrn_n_s32(gl, 16),                  \
 150                                  vrshrn_n_s32(gh, 16)));                \
 151     v = vqmovun_s16(vcombine_s16(vrshrn_n_s32(bl, 16),                  \
 152                                  vrshrn_n_s32(bh, 16)));                \
 153     STR_ ## FMT(out + off, y, u, v);                                    \
 154   }                                                                     \
 155 }
 156
 157 #define v255 vmov_n_u8(255)
 158
 159 #define STR_Rgb(out, r, g, b) do {                                      \
 160   const uint8x8x3_t r_g_b = {{ r, g, b }};                              \
 161   vst3_u8(out, r_g_b);                                                  \
 162 } while (0)
 163
 164 #define STR_Bgr(out, r, g, b) do {                                      \
 165   const uint8x8x3_t b_g_r = {{ b, g, r }};                              \
 166   vst3_u8(out, b_g_r);                                                  \
 167 } while (0)
 168
 169 #define STR_Rgba(out, r, g, b) do {                                     \
 170   const uint8x8x4_t r_g_b_v255 = {{ r, g, b, v255 }};                   \
 171   vst4_u8(out, r_g_b_v255);                                             \
 172 } while (0)
 173
 174 #define STR_Bgra(out, r, g, b) do {                                     \
 175   const uint8x8x4_t b_g_r_v255 = {{ b, g, r, v255 }};                   \
 176   vst4_u8(out, b_g_r_v255);                                             \
 177 } while (0)
 178
 179 #define CONVERT1(FMT, XSTEP, N, src_y, src_uv, rgb, cur_x) {            \
 180   int i;                                                                \
 181   for (i = 0; i < N; i++) {                                             \
 182     int off = ((cur_x) + i) * XSTEP;                                    \
 183     int y = src_y[(cur_x) + i];                                         \
 184     int u = (src_uv)[i];                                                \
 185     int v = (src_uv)[i + 16];                                           \
 186     VP8YuvTo ## FMT(y, u, v, rgb + off);                                \
 187   }                                                                     \
 188 }
 189
 190 #define CONVERT2RGB_8(FMT, XSTEP, top_y, bottom_y, uv,                  \
 191                       top_dst, bottom_dst, cur_x, len) {                \
 192   if (top_y) {                                                          \
 193     CONVERT8(FMT, XSTEP, len, top_y, uv, top_dst, cur_x)                \
 194   }                                                                     \
 195   if (bottom_y) {                                                       \
 196     CONVERT8(FMT, XSTEP, len, bottom_y, (uv) + 32, bottom_dst, cur_x)   \
 197   }                                                                     \
 198 }
 199
 200 #define CONVERT2RGB_1(FMT, XSTEP, top_y, bottom_y, uv,                  \
 201                       top_dst, bottom_dst, cur_x, len) {                \
 202   if (top_y) {                                                          \
 203     CONVERT1(FMT, XSTEP, len, top_y, uv, top_dst, cur_x);               \
 204   }                                                                     \
 205   if (bottom_y) {                                                       \
 206     CONVERT1(FMT, XSTEP, len, bottom_y, (uv) + 32, bottom_dst, cur_x);  \
 207   }                                                                     \
 208 }
 209
 210 #define NEON_UPSAMPLE_FUNC(FUNC_NAME, FMT, XSTEP)                       \
 211 static void FUNC_NAME(const uint8_t *top_y, const uint8_t *bottom_y,    \
 212                       const uint8_t *top_u, const uint8_t *top_v,       \
 213                       const uint8_t *cur_u, const uint8_t *cur_v,       \
 214                       uint8_t *top_dst, uint8_t *bottom_dst, int len) { \
 215   int block;                                                            \
 216   /* 16 byte aligned array to cache reconstructed u and v */            \
 217   uint8_t uv_buf[2 * 32 + 15];                                          \
 218   uint8_t *const r_uv = (uint8_t*)((uintptr_t)(uv_buf + 15) & ~15);     \
 219   const int uv_len = (len + 1) >> 1;                                    \
 220   /* 9 pixels must be read-able for each block */                       \
 221   const int num_blocks = (uv_len - 1) >> 3;                             \
 222   const int leftover = uv_len - num_blocks * 8;                         \
 223   const int last_pos = 1 + 16 * num_blocks;                             \
 224                                                                         \
 225   const int u_diag = ((top_u[0] + cur_u[0]) >> 1) + 1;                  \
 226   const int v_diag = ((top_v[0] + cur_v[0]) >> 1) + 1;                  \
 227                                                                         \
 228   const int16x4_t cf16 = vld1_s16(coef);                                \
 229   const int32x2_t cf32 = vmov_n_s32(CY);                                \
 230   const uint8x8_t u16  = vmov_n_u8(16);                                 \
 231   const uint8x8_t u128 = vmov_n_u8(128);                                \
 232                                                                         \
 233   /* Treat the first pixel in regular way */                            \
 234   if (top_y) {                                                          \
 235     const int u0 = (top_u[0] + u_diag) >> 1;                            \
 236     const int v0 = (top_v[0] + v_diag) >> 1;                            \
 237     VP8YuvTo ## FMT(top_y[0], u0, v0, top_dst);                         \
 238   }                                                                     \
 239   if (bottom_y) {                                                       \
 240     const int u0 = (cur_u[0] + u_diag) >> 1;                            \
 241     const int v0 = (cur_v[0] + v_diag) >> 1;                            \
 242     VP8YuvTo ## FMT(bottom_y[0], u0, v0, bottom_dst);                   \
 243   }                                                                     \
 244                                                                         \
 245   for (block = 0; block < num_blocks; ++block) {                        \
 246     UPSAMPLE_16PIXELS(top_u, cur_u, r_uv);                              \
 247     UPSAMPLE_16PIXELS(top_v, cur_v, r_uv + 16);                         \
 248     CONVERT2RGB_8(FMT, XSTEP, top_y, bottom_y, r_uv,                    \
 249                   top_dst, bottom_dst, 16 * block + 1, 16);             \
 250     top_u += 8;                                                         \
 251     cur_u += 8;                                                         \
 252     top_v += 8;                                                         \
 253     cur_v += 8;                                                         \
 254   }                                                                     \
 255                                                                         \
 256   UPSAMPLE_LAST_BLOCK(top_u, cur_u, leftover, r_uv);                    \
 257   UPSAMPLE_LAST_BLOCK(top_v, cur_v, leftover, r_uv + 16);               \
 258   CONVERT2RGB_1(FMT, XSTEP, top_y, bottom_y, r_uv,                      \
 259                 top_dst, bottom_dst, last_pos, len - last_pos);         \
 260 }
 261
 262 // NEON variants of the fancy upsampler.
 263 NEON_UPSAMPLE_FUNC(UpsampleRgbLinePairNEON,  Rgb,  3)
 264 NEON_UPSAMPLE_FUNC(UpsampleBgrLinePairNEON,  Bgr,  3)
 265 NEON_UPSAMPLE_FUNC(UpsampleRgbaLinePairNEON, Rgba, 4)
 266 NEON_UPSAMPLE_FUNC(UpsampleBgraLinePairNEON, Bgra, 4)
 267
 268 #endif  // FANCY_UPSAMPLING
 269
 270 #endif   // WEBP_USE_NEON
 271
 272 //------------------------------------------------------------------------------
 273
 274 extern WebPUpsampleLinePairFunc WebPUpsamplers[/* MODE_LAST */];
 275
 276 void WebPInitUpsamplersNEON(void) {
 277 #if defined(WEBP_USE_NEON)
 278   WebPUpsamplers[MODE_RGB]  = UpsampleRgbLinePairNEON;
 279   WebPUpsamplers[MODE_RGBA] = UpsampleRgbaLinePairNEON;
 280   WebPUpsamplers[MODE_BGR]  = UpsampleBgrLinePairNEON;
 281   WebPUpsamplers[MODE_BGRA] = UpsampleBgraLinePairNEON;
 282 #endif   // WEBP_USE_NEON
 283 }
 284
 285 void WebPInitPremultiplyNEON(void) {
 286 #if defined(WEBP_USE_NEON)
 287   WebPUpsamplers[MODE_rgbA] = UpsampleRgbaLinePairNEON;
 288   WebPUpsamplers[MODE_bgrA] = UpsampleBgraLinePairNEON;
 289 #endif   // WEBP_USE_NEON
 290 }
 291
 292 #if defined(__cplusplus) || defined(c_plusplus)
 293 }    // extern "C"
 294 #endif