github.com/cellofellow/gopkg@v0.0.0-20140722061823-eec0544a62ad/image/webp/libwebp/src/dsp/upsampling_neon.c (about) 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(WEBP_USE_NEON) 18 19 #include <assert.h> 20 #include <arm_neon.h> 21 #include <string.h> 22 #include "./yuv.h" 23 24 #ifdef FANCY_UPSAMPLING 25 26 //----------------------------------------------------------------------------- 27 // U/V upsampling 28 29 // Loads 9 pixels each from rows r1 and r2 and generates 16 pixels. 30 #define UPSAMPLE_16PIXELS(r1, r2, out) { \ 31 uint8x8_t a = vld1_u8(r1); \ 32 uint8x8_t b = vld1_u8(r1 + 1); \ 33 uint8x8_t c = vld1_u8(r2); \ 34 uint8x8_t d = vld1_u8(r2 + 1); \ 35 \ 36 uint16x8_t al = vshll_n_u8(a, 1); \ 37 uint16x8_t bl = vshll_n_u8(b, 1); \ 38 uint16x8_t cl = vshll_n_u8(c, 1); \ 39 uint16x8_t dl = vshll_n_u8(d, 1); \ 40 \ 41 uint8x8_t diag1, diag2; \ 42 uint16x8_t sl; \ 43 \ 44 /* a + b + c + d */ \ 45 sl = vaddl_u8(a, b); \ 46 sl = vaddw_u8(sl, c); \ 47 sl = vaddw_u8(sl, d); \ 48 \ 49 al = vaddq_u16(sl, al); /* 3a + b + c + d */ \ 50 bl = vaddq_u16(sl, bl); /* a + 3b + c + d */ \ 51 \ 52 al = vaddq_u16(al, dl); /* 3a + b + c + 3d */ \ 53 bl = vaddq_u16(bl, cl); /* a + 3b + 3c + d */ \ 54 \ 55 diag2 = vshrn_n_u16(al, 3); \ 56 diag1 = vshrn_n_u16(bl, 3); \ 57 \ 58 a = vrhadd_u8(a, diag1); \ 59 b = vrhadd_u8(b, diag2); \ 60 c = vrhadd_u8(c, diag2); \ 61 d = vrhadd_u8(d, diag1); \ 62 \ 63 { \ 64 const uint8x8x2_t a_b = {{ a, b }}; \ 65 const uint8x8x2_t c_d = {{ c, d }}; \ 66 vst2_u8(out, a_b); \ 67 vst2_u8(out + 32, c_d); \ 68 } \ 69 } 70 71 // Turn the macro into a function for reducing code-size when non-critical 72 static void Upsample16Pixels(const uint8_t *r1, const uint8_t *r2, 73 uint8_t *out) { 74 UPSAMPLE_16PIXELS(r1, r2, out); 75 } 76 77 #define UPSAMPLE_LAST_BLOCK(tb, bb, num_pixels, out) { \ 78 uint8_t r1[9], r2[9]; \ 79 memcpy(r1, (tb), (num_pixels)); \ 80 memcpy(r2, (bb), (num_pixels)); \ 81 /* replicate last byte */ \ 82 memset(r1 + (num_pixels), r1[(num_pixels) - 1], 9 - (num_pixels)); \ 83 memset(r2 + (num_pixels), r2[(num_pixels) - 1], 9 - (num_pixels)); \ 84 Upsample16Pixels(r1, r2, out); \ 85 } 86 87 //----------------------------------------------------------------------------- 88 // YUV->RGB conversion 89 90 static const int16_t kCoeffs[4] = { kYScale, kVToR, kUToG, kVToG }; 91 92 #define v255 vmov_n_u8(255) 93 94 #define STORE_Rgb(out, r, g, b) do { \ 95 const uint8x8x3_t r_g_b = {{ r, g, b }}; \ 96 vst3_u8(out, r_g_b); \ 97 } while (0) 98 99 #define STORE_Bgr(out, r, g, b) do { \ 100 const uint8x8x3_t b_g_r = {{ b, g, r }}; \ 101 vst3_u8(out, b_g_r); \ 102 } while (0) 103 104 #define STORE_Rgba(out, r, g, b) do { \ 105 const uint8x8x4_t r_g_b_v255 = {{ r, g, b, v255 }}; \ 106 vst4_u8(out, r_g_b_v255); \ 107 } while (0) 108 109 #define STORE_Bgra(out, r, g, b) do { \ 110 const uint8x8x4_t b_g_r_v255 = {{ b, g, r, v255 }}; \ 111 vst4_u8(out, b_g_r_v255); \ 112 } while (0) 113 114 #define CONVERT8(FMT, XSTEP, N, src_y, src_uv, out, cur_x) { \ 115 int i; \ 116 for (i = 0; i < N; i += 8) { \ 117 const int off = ((cur_x) + i) * XSTEP; \ 118 uint8x8_t y = vld1_u8((src_y) + (cur_x) + i); \ 119 uint8x8_t u = vld1_u8((src_uv) + i); \ 120 uint8x8_t v = vld1_u8((src_uv) + i + 16); \ 121 const int16x8_t yy = vreinterpretq_s16_u16(vsubl_u8(y, u16)); \ 122 const int16x8_t uu = vreinterpretq_s16_u16(vsubl_u8(u, u128)); \ 123 const int16x8_t vv = vreinterpretq_s16_u16(vsubl_u8(v, u128)); \ 124 int32x4_t yl = vmull_lane_s16(vget_low_s16(yy), cf16, 0); \ 125 int32x4_t yh = vmull_lane_s16(vget_high_s16(yy), cf16, 0); \ 126 const int32x4_t rl = vmlal_lane_s16(yl, vget_low_s16(vv), cf16, 1);\ 127 const int32x4_t rh = vmlal_lane_s16(yh, vget_high_s16(vv), cf16, 1);\ 128 int32x4_t gl = vmlsl_lane_s16(yl, vget_low_s16(uu), cf16, 2); \ 129 int32x4_t gh = vmlsl_lane_s16(yh, vget_high_s16(uu), cf16, 2); \ 130 const int32x4_t bl = vmovl_s16(vget_low_s16(uu)); \ 131 const int32x4_t bh = vmovl_s16(vget_high_s16(uu)); \ 132 gl = vmlsl_lane_s16(gl, vget_low_s16(vv), cf16, 3); \ 133 gh = vmlsl_lane_s16(gh, vget_high_s16(vv), cf16, 3); \ 134 yl = vmlaq_lane_s32(yl, bl, cf32, 0); \ 135 yh = vmlaq_lane_s32(yh, bh, cf32, 0); \ 136 /* vrshrn_n_s32() already incorporates the rounding constant */ \ 137 y = vqmovun_s16(vcombine_s16(vrshrn_n_s32(rl, YUV_FIX2), \ 138 vrshrn_n_s32(rh, YUV_FIX2))); \ 139 u = vqmovun_s16(vcombine_s16(vrshrn_n_s32(gl, YUV_FIX2), \ 140 vrshrn_n_s32(gh, YUV_FIX2))); \ 141 v = vqmovun_s16(vcombine_s16(vrshrn_n_s32(yl, YUV_FIX2), \ 142 vrshrn_n_s32(yh, YUV_FIX2))); \ 143 STORE_ ## FMT(out + off, y, u, v); \ 144 } \ 145 } 146 147 #define CONVERT1(FUNC, XSTEP, N, src_y, src_uv, rgb, cur_x) { \ 148 int i; \ 149 for (i = 0; i < N; i++) { \ 150 const int off = ((cur_x) + i) * XSTEP; \ 151 const int y = src_y[(cur_x) + i]; \ 152 const int u = (src_uv)[i]; \ 153 const int v = (src_uv)[i + 16]; \ 154 FUNC(y, u, v, rgb + off); \ 155 } \ 156 } 157 158 #define CONVERT2RGB_8(FMT, XSTEP, top_y, bottom_y, uv, \ 159 top_dst, bottom_dst, cur_x, len) { \ 160 CONVERT8(FMT, XSTEP, len, top_y, uv, top_dst, cur_x) \ 161 if (bottom_y != NULL) { \ 162 CONVERT8(FMT, XSTEP, len, bottom_y, (uv) + 32, bottom_dst, cur_x) \ 163 } \ 164 } 165 166 #define CONVERT2RGB_1(FUNC, XSTEP, top_y, bottom_y, uv, \ 167 top_dst, bottom_dst, cur_x, len) { \ 168 CONVERT1(FUNC, XSTEP, len, top_y, uv, top_dst, cur_x); \ 169 if (bottom_y != NULL) { \ 170 CONVERT1(FUNC, XSTEP, len, bottom_y, (uv) + 32, bottom_dst, cur_x); \ 171 } \ 172 } 173 174 #define NEON_UPSAMPLE_FUNC(FUNC_NAME, FMT, XSTEP) \ 175 static void FUNC_NAME(const uint8_t *top_y, const uint8_t *bottom_y, \ 176 const uint8_t *top_u, const uint8_t *top_v, \ 177 const uint8_t *cur_u, const uint8_t *cur_v, \ 178 uint8_t *top_dst, uint8_t *bottom_dst, int len) { \ 179 int block; \ 180 /* 16 byte aligned array to cache reconstructed u and v */ \ 181 uint8_t uv_buf[2 * 32 + 15]; \ 182 uint8_t *const r_uv = (uint8_t*)((uintptr_t)(uv_buf + 15) & ~15); \ 183 const int uv_len = (len + 1) >> 1; \ 184 /* 9 pixels must be read-able for each block */ \ 185 const int num_blocks = (uv_len - 1) >> 3; \ 186 const int leftover = uv_len - num_blocks * 8; \ 187 const int last_pos = 1 + 16 * num_blocks; \ 188 \ 189 const int u_diag = ((top_u[0] + cur_u[0]) >> 1) + 1; \ 190 const int v_diag = ((top_v[0] + cur_v[0]) >> 1) + 1; \ 191 \ 192 const int16x4_t cf16 = vld1_s16(kCoeffs); \ 193 const int32x2_t cf32 = vmov_n_s32(kUToB); \ 194 const uint8x8_t u16 = vmov_n_u8(16); \ 195 const uint8x8_t u128 = vmov_n_u8(128); \ 196 \ 197 /* Treat the first pixel in regular way */ \ 198 assert(top_y != NULL); \ 199 { \ 200 const int u0 = (top_u[0] + u_diag) >> 1; \ 201 const int v0 = (top_v[0] + v_diag) >> 1; \ 202 VP8YuvTo ## FMT(top_y[0], u0, v0, top_dst); \ 203 } \ 204 if (bottom_y != NULL) { \ 205 const int u0 = (cur_u[0] + u_diag) >> 1; \ 206 const int v0 = (cur_v[0] + v_diag) >> 1; \ 207 VP8YuvTo ## FMT(bottom_y[0], u0, v0, bottom_dst); \ 208 } \ 209 \ 210 for (block = 0; block < num_blocks; ++block) { \ 211 UPSAMPLE_16PIXELS(top_u, cur_u, r_uv); \ 212 UPSAMPLE_16PIXELS(top_v, cur_v, r_uv + 16); \ 213 CONVERT2RGB_8(FMT, XSTEP, top_y, bottom_y, r_uv, \ 214 top_dst, bottom_dst, 16 * block + 1, 16); \ 215 top_u += 8; \ 216 cur_u += 8; \ 217 top_v += 8; \ 218 cur_v += 8; \ 219 } \ 220 \ 221 UPSAMPLE_LAST_BLOCK(top_u, cur_u, leftover, r_uv); \ 222 UPSAMPLE_LAST_BLOCK(top_v, cur_v, leftover, r_uv + 16); \ 223 CONVERT2RGB_1(VP8YuvTo ## FMT, XSTEP, top_y, bottom_y, r_uv, \ 224 top_dst, bottom_dst, last_pos, len - last_pos); \ 225 } 226 227 // NEON variants of the fancy upsampler. 228 NEON_UPSAMPLE_FUNC(UpsampleRgbLinePairNEON, Rgb, 3) 229 NEON_UPSAMPLE_FUNC(UpsampleBgrLinePairNEON, Bgr, 3) 230 NEON_UPSAMPLE_FUNC(UpsampleRgbaLinePairNEON, Rgba, 4) 231 NEON_UPSAMPLE_FUNC(UpsampleBgraLinePairNEON, Bgra, 4) 232 233 #endif // FANCY_UPSAMPLING 234 235 #endif // WEBP_USE_NEON 236 237 //------------------------------------------------------------------------------ 238 239 #ifdef FANCY_UPSAMPLING 240 241 extern WebPUpsampleLinePairFunc WebPUpsamplers[/* MODE_LAST */]; 242 243 void WebPInitUpsamplersNEON(void) { 244 #if defined(WEBP_USE_NEON) 245 WebPUpsamplers[MODE_RGB] = UpsampleRgbLinePairNEON; 246 WebPUpsamplers[MODE_RGBA] = UpsampleRgbaLinePairNEON; 247 WebPUpsamplers[MODE_BGR] = UpsampleBgrLinePairNEON; 248 WebPUpsamplers[MODE_BGRA] = UpsampleBgraLinePairNEON; 249 #endif // WEBP_USE_NEON 250 } 251 252 void WebPInitPremultiplyNEON(void) { 253 #if defined(WEBP_USE_NEON) 254 WebPUpsamplers[MODE_rgbA] = UpsampleRgbaLinePairNEON; 255 WebPUpsamplers[MODE_bgrA] = UpsampleBgraLinePairNEON; 256 #endif // WEBP_USE_NEON 257 } 258 259 #else 260 261 // this empty function is to avoid an empty .o 262 void WebPInitPremultiplyNEON(void) {} 263 264 #endif // FANCY_UPSAMPLING 265