1 // Copyright 2017 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 // YUV->RGB conversion functions
11 //
12 // Author: Skal (pascal.massimino@gmail.com)
13 
14 #include "src/dsp/yuv.h"
15 
16 #if defined(WEBP_USE_NEON)
17 
18 #include <assert.h>
19 #include <stdlib.h>
20 
21 #include "src/dsp/neon.h"
22 
23 //-----------------------------------------------------------------------------
24 
ConvertRGBToY_NEON(const uint8x8_t R,const uint8x8_t G,const uint8x8_t B)25 static uint8x8_t ConvertRGBToY_NEON(const uint8x8_t R,
26                                     const uint8x8_t G,
27                                     const uint8x8_t B) {
28   const uint16x8_t r = vmovl_u8(R);
29   const uint16x8_t g = vmovl_u8(G);
30   const uint16x8_t b = vmovl_u8(B);
31   const uint16x4_t r_lo = vget_low_u16(r);
32   const uint16x4_t r_hi = vget_high_u16(r);
33   const uint16x4_t g_lo = vget_low_u16(g);
34   const uint16x4_t g_hi = vget_high_u16(g);
35   const uint16x4_t b_lo = vget_low_u16(b);
36   const uint16x4_t b_hi = vget_high_u16(b);
37   const uint32x4_t tmp0_lo = vmull_n_u16(         r_lo, 16839u);
38   const uint32x4_t tmp0_hi = vmull_n_u16(         r_hi, 16839u);
39   const uint32x4_t tmp1_lo = vmlal_n_u16(tmp0_lo, g_lo, 33059u);
40   const uint32x4_t tmp1_hi = vmlal_n_u16(tmp0_hi, g_hi, 33059u);
41   const uint32x4_t tmp2_lo = vmlal_n_u16(tmp1_lo, b_lo, 6420u);
42   const uint32x4_t tmp2_hi = vmlal_n_u16(tmp1_hi, b_hi, 6420u);
43   const uint16x8_t Y1 = vcombine_u16(vrshrn_n_u32(tmp2_lo, 16),
44                                      vrshrn_n_u32(tmp2_hi, 16));
45   const uint16x8_t Y2 = vaddq_u16(Y1, vdupq_n_u16(16));
46   return vqmovn_u16(Y2);
47 }
48 
ConvertRGB24ToY_NEON(const uint8_t * rgb,uint8_t * y,int width)49 static void ConvertRGB24ToY_NEON(const uint8_t* rgb, uint8_t* y, int width) {
50   int i;
51   for (i = 0; i + 8 <= width; i += 8, rgb += 3 * 8) {
52     const uint8x8x3_t RGB = vld3_u8(rgb);
53     const uint8x8_t Y = ConvertRGBToY_NEON(RGB.val[0], RGB.val[1], RGB.val[2]);
54     vst1_u8(y + i, Y);
55   }
56   for (; i < width; ++i, rgb += 3) {   // left-over
57     y[i] = VP8RGBToY(rgb[0], rgb[1], rgb[2], YUV_HALF);
58   }
59 }
60 
ConvertBGR24ToY_NEON(const uint8_t * bgr,uint8_t * y,int width)61 static void ConvertBGR24ToY_NEON(const uint8_t* bgr, uint8_t* y, int width) {
62   int i;
63   for (i = 0; i + 8 <= width; i += 8, bgr += 3 * 8) {
64     const uint8x8x3_t BGR = vld3_u8(bgr);
65     const uint8x8_t Y = ConvertRGBToY_NEON(BGR.val[2], BGR.val[1], BGR.val[0]);
66     vst1_u8(y + i, Y);
67   }
68   for (; i < width; ++i, bgr += 3) {  // left-over
69     y[i] = VP8RGBToY(bgr[2], bgr[1], bgr[0], YUV_HALF);
70   }
71 }
72 
ConvertARGBToY_NEON(const uint32_t * argb,uint8_t * y,int width)73 static void ConvertARGBToY_NEON(const uint32_t* argb, uint8_t* y, int width) {
74   int i;
75   for (i = 0; i + 8 <= width; i += 8) {
76     const uint8x8x4_t RGB = vld4_u8((const uint8_t*)&argb[i]);
77     const uint8x8_t Y = ConvertRGBToY_NEON(RGB.val[2], RGB.val[1], RGB.val[0]);
78     vst1_u8(y + i, Y);
79   }
80   for (; i < width; ++i) {   // left-over
81     const uint32_t p = argb[i];
82     y[i] = VP8RGBToY((p >> 16) & 0xff, (p >> 8) & 0xff, (p >>  0) & 0xff,
83                      YUV_HALF);
84   }
85 }
86 
87 //-----------------------------------------------------------------------------
88 
89 // computes: DST_s16 = [(C0 * r + C1 * g + C2 * b) >> 16] + CST
90 #define MULTIPLY_16b_PREAMBLE(r, g, b)                           \
91   const int16x4_t r_lo = vreinterpret_s16_u16(vget_low_u16(r));  \
92   const int16x4_t r_hi = vreinterpret_s16_u16(vget_high_u16(r)); \
93   const int16x4_t g_lo = vreinterpret_s16_u16(vget_low_u16(g));  \
94   const int16x4_t g_hi = vreinterpret_s16_u16(vget_high_u16(g)); \
95   const int16x4_t b_lo = vreinterpret_s16_u16(vget_low_u16(b));  \
96   const int16x4_t b_hi = vreinterpret_s16_u16(vget_high_u16(b))
97 
98 #define MULTIPLY_16b(C0, C1, C2, CST, DST_s16) do {              \
99   const int32x4_t tmp0_lo = vmull_n_s16(         r_lo, C0);      \
100   const int32x4_t tmp0_hi = vmull_n_s16(         r_hi, C0);      \
101   const int32x4_t tmp1_lo = vmlal_n_s16(tmp0_lo, g_lo, C1);      \
102   const int32x4_t tmp1_hi = vmlal_n_s16(tmp0_hi, g_hi, C1);      \
103   const int32x4_t tmp2_lo = vmlal_n_s16(tmp1_lo, b_lo, C2);      \
104   const int32x4_t tmp2_hi = vmlal_n_s16(tmp1_hi, b_hi, C2);      \
105   const int16x8_t tmp3 = vcombine_s16(vshrn_n_s32(tmp2_lo, 16),  \
106                                       vshrn_n_s32(tmp2_hi, 16)); \
107   DST_s16 = vaddq_s16(tmp3, vdupq_n_s16(CST));                   \
108 } while (0)
109 
110 // This needs to be a macro, since (128 << SHIFT) needs to be an immediate.
111 #define CONVERT_RGB_TO_UV(r, g, b, SHIFT, U_DST, V_DST) do {     \
112   MULTIPLY_16b_PREAMBLE(r, g, b);                                \
113   MULTIPLY_16b(-9719, -19081, 28800, 128 << SHIFT, U_DST);       \
114   MULTIPLY_16b(28800, -24116, -4684, 128 << SHIFT, V_DST);       \
115 } while (0)
116 
ConvertRGBA32ToUV_NEON(const uint16_t * rgb,uint8_t * u,uint8_t * v,int width)117 static void ConvertRGBA32ToUV_NEON(const uint16_t* rgb,
118                                    uint8_t* u, uint8_t* v, int width) {
119   int i;
120   for (i = 0; i + 8 <= width; i += 8, rgb += 4 * 8) {
121     const uint16x8x4_t RGB = vld4q_u16((const uint16_t*)rgb);
122     int16x8_t U, V;
123     CONVERT_RGB_TO_UV(RGB.val[0], RGB.val[1], RGB.val[2], 2, U, V);
124     vst1_u8(u + i, vqrshrun_n_s16(U, 2));
125     vst1_u8(v + i, vqrshrun_n_s16(V, 2));
126   }
127   for (; i < width; i += 1, rgb += 4) {
128     const int r = rgb[0], g = rgb[1], b = rgb[2];
129     u[i] = VP8RGBToU(r, g, b, YUV_HALF << 2);
130     v[i] = VP8RGBToV(r, g, b, YUV_HALF << 2);
131   }
132 }
133 
ConvertARGBToUV_NEON(const uint32_t * argb,uint8_t * u,uint8_t * v,int src_width,int do_store)134 static void ConvertARGBToUV_NEON(const uint32_t* argb, uint8_t* u, uint8_t* v,
135                                  int src_width, int do_store) {
136   int i;
137   for (i = 0; i + 16 <= src_width; i += 16, u += 8, v += 8) {
138     const uint8x16x4_t RGB = vld4q_u8((const uint8_t*)&argb[i]);
139     const uint16x8_t R = vpaddlq_u8(RGB.val[2]);  // pair-wise adds
140     const uint16x8_t G = vpaddlq_u8(RGB.val[1]);
141     const uint16x8_t B = vpaddlq_u8(RGB.val[0]);
142     int16x8_t U_tmp, V_tmp;
143     CONVERT_RGB_TO_UV(R, G, B, 1, U_tmp, V_tmp);
144     {
145       const uint8x8_t U = vqrshrun_n_s16(U_tmp, 1);
146       const uint8x8_t V = vqrshrun_n_s16(V_tmp, 1);
147       if (do_store) {
148         vst1_u8(u, U);
149         vst1_u8(v, V);
150       } else {
151         const uint8x8_t prev_u = vld1_u8(u);
152         const uint8x8_t prev_v = vld1_u8(v);
153         vst1_u8(u, vrhadd_u8(U, prev_u));
154         vst1_u8(v, vrhadd_u8(V, prev_v));
155       }
156     }
157   }
158   if (i < src_width) {  // left-over
159     WebPConvertARGBToUV_C(argb + i, u, v, src_width - i, do_store);
160   }
161 }
162 
163 
164 //------------------------------------------------------------------------------
165 
166 extern void WebPInitConvertARGBToYUVNEON(void);
167 
WebPInitConvertARGBToYUVNEON(void)168 WEBP_TSAN_IGNORE_FUNCTION void WebPInitConvertARGBToYUVNEON(void) {
169   WebPConvertRGB24ToY = ConvertRGB24ToY_NEON;
170   WebPConvertBGR24ToY = ConvertBGR24ToY_NEON;
171   WebPConvertARGBToY = ConvertARGBToY_NEON;
172   WebPConvertARGBToUV = ConvertARGBToUV_NEON;
173   WebPConvertRGBA32ToUV = ConvertRGBA32ToUV_NEON;
174 }
175 
176 //------------------------------------------------------------------------------
177 
178 #define MAX_Y ((1 << 10) - 1)    // 10b precision over 16b-arithmetic
clip_y_NEON(int v)179 static uint16_t clip_y_NEON(int v) {
180   return (v < 0) ? 0 : (v > MAX_Y) ? MAX_Y : (uint16_t)v;
181 }
182 
SharpYUVUpdateY_NEON(const uint16_t * ref,const uint16_t * src,uint16_t * dst,int len)183 static uint64_t SharpYUVUpdateY_NEON(const uint16_t* ref, const uint16_t* src,
184                                      uint16_t* dst, int len) {
185   int i;
186   const int16x8_t zero = vdupq_n_s16(0);
187   const int16x8_t max = vdupq_n_s16(MAX_Y);
188   uint64x2_t sum = vdupq_n_u64(0);
189   uint64_t diff;
190 
191   for (i = 0; i + 8 <= len; i += 8) {
192     const int16x8_t A = vreinterpretq_s16_u16(vld1q_u16(ref + i));
193     const int16x8_t B = vreinterpretq_s16_u16(vld1q_u16(src + i));
194     const int16x8_t C = vreinterpretq_s16_u16(vld1q_u16(dst + i));
195     const int16x8_t D = vsubq_s16(A, B);       // diff_y
196     const int16x8_t F = vaddq_s16(C, D);       // new_y
197     const uint16x8_t H =
198         vreinterpretq_u16_s16(vmaxq_s16(vminq_s16(F, max), zero));
199     const int16x8_t I = vabsq_s16(D);          // abs(diff_y)
200     vst1q_u16(dst + i, H);
201     sum = vpadalq_u32(sum, vpaddlq_u16(vreinterpretq_u16_s16(I)));
202   }
203   diff = vgetq_lane_u64(sum, 0) + vgetq_lane_u64(sum, 1);
204   for (; i < len; ++i) {
205     const int diff_y = ref[i] - src[i];
206     const int new_y = (int)(dst[i]) + diff_y;
207     dst[i] = clip_y_NEON(new_y);
208     diff += (uint64_t)(abs(diff_y));
209   }
210   return diff;
211 }
212 
SharpYUVUpdateRGB_NEON(const int16_t * ref,const int16_t * src,int16_t * dst,int len)213 static void SharpYUVUpdateRGB_NEON(const int16_t* ref, const int16_t* src,
214                                    int16_t* dst, int len) {
215   int i;
216   for (i = 0; i + 8 <= len; i += 8) {
217     const int16x8_t A = vld1q_s16(ref + i);
218     const int16x8_t B = vld1q_s16(src + i);
219     const int16x8_t C = vld1q_s16(dst + i);
220     const int16x8_t D = vsubq_s16(A, B);   // diff_uv
221     const int16x8_t E = vaddq_s16(C, D);   // new_uv
222     vst1q_s16(dst + i, E);
223   }
224   for (; i < len; ++i) {
225     const int diff_uv = ref[i] - src[i];
226     dst[i] += diff_uv;
227   }
228 }
229 
SharpYUVFilterRow_NEON(const int16_t * A,const int16_t * B,int len,const uint16_t * best_y,uint16_t * out)230 static void SharpYUVFilterRow_NEON(const int16_t* A, const int16_t* B, int len,
231                                    const uint16_t* best_y, uint16_t* out) {
232   int i;
233   const int16x8_t max = vdupq_n_s16(MAX_Y);
234   const int16x8_t zero = vdupq_n_s16(0);
235   for (i = 0; i + 8 <= len; i += 8) {
236     const int16x8_t a0 = vld1q_s16(A + i + 0);
237     const int16x8_t a1 = vld1q_s16(A + i + 1);
238     const int16x8_t b0 = vld1q_s16(B + i + 0);
239     const int16x8_t b1 = vld1q_s16(B + i + 1);
240     const int16x8_t a0b1 = vaddq_s16(a0, b1);
241     const int16x8_t a1b0 = vaddq_s16(a1, b0);
242     const int16x8_t a0a1b0b1 = vaddq_s16(a0b1, a1b0);  // A0+A1+B0+B1
243     const int16x8_t a0b1_2 = vaddq_s16(a0b1, a0b1);    // 2*(A0+B1)
244     const int16x8_t a1b0_2 = vaddq_s16(a1b0, a1b0);    // 2*(A1+B0)
245     const int16x8_t c0 = vshrq_n_s16(vaddq_s16(a0b1_2, a0a1b0b1), 3);
246     const int16x8_t c1 = vshrq_n_s16(vaddq_s16(a1b0_2, a0a1b0b1), 3);
247     const int16x8_t d0 = vaddq_s16(c1, a0);
248     const int16x8_t d1 = vaddq_s16(c0, a1);
249     const int16x8_t e0 = vrshrq_n_s16(d0, 1);
250     const int16x8_t e1 = vrshrq_n_s16(d1, 1);
251     const int16x8x2_t f = vzipq_s16(e0, e1);
252     const int16x8_t g0 = vreinterpretq_s16_u16(vld1q_u16(best_y + 2 * i + 0));
253     const int16x8_t g1 = vreinterpretq_s16_u16(vld1q_u16(best_y + 2 * i + 8));
254     const int16x8_t h0 = vaddq_s16(g0, f.val[0]);
255     const int16x8_t h1 = vaddq_s16(g1, f.val[1]);
256     const int16x8_t i0 = vmaxq_s16(vminq_s16(h0, max), zero);
257     const int16x8_t i1 = vmaxq_s16(vminq_s16(h1, max), zero);
258     vst1q_u16(out + 2 * i + 0, vreinterpretq_u16_s16(i0));
259     vst1q_u16(out + 2 * i + 8, vreinterpretq_u16_s16(i1));
260   }
261   for (; i < len; ++i) {
262     const int a0b1 = A[i + 0] + B[i + 1];
263     const int a1b0 = A[i + 1] + B[i + 0];
264     const int a0a1b0b1 = a0b1 + a1b0 + 8;
265     const int v0 = (8 * A[i + 0] + 2 * a1b0 + a0a1b0b1) >> 4;
266     const int v1 = (8 * A[i + 1] + 2 * a0b1 + a0a1b0b1) >> 4;
267     out[2 * i + 0] = clip_y_NEON(best_y[2 * i + 0] + v0);
268     out[2 * i + 1] = clip_y_NEON(best_y[2 * i + 1] + v1);
269   }
270 }
271 #undef MAX_Y
272 
273 //------------------------------------------------------------------------------
274 
275 extern void WebPInitSharpYUVNEON(void);
276 
WebPInitSharpYUVNEON(void)277 WEBP_TSAN_IGNORE_FUNCTION void WebPInitSharpYUVNEON(void) {
278   WebPSharpYUVUpdateY = SharpYUVUpdateY_NEON;
279   WebPSharpYUVUpdateRGB = SharpYUVUpdateRGB_NEON;
280   WebPSharpYUVFilterRow = SharpYUVFilterRow_NEON;
281 }
282 
283 #else  // !WEBP_USE_NEON
284 
285 WEBP_DSP_INIT_STUB(WebPInitConvertARGBToYUVNEON)
286 WEBP_DSP_INIT_STUB(WebPInitSharpYUVNEON)
287 
288 #endif  // WEBP_USE_NEON
289