// Copyright 2011 Google Inc. All Rights Reserved.

//

// Use of this source code is governed by a BSD-style license

// that can be found in the COPYING file in the root of the source

// tree. An additional intellectual property rights grant can be found

// in the file PATENTS. All contributing project authors may

// be found in the AUTHORS file in the root of the source tree.

// -----------------------------------------------------------------------------

//

// NEON version of YUV to RGB upsampling functions.

//

// Author: mans@mansr.com (Mans Rullgard)

// Based on SSE code by: somnath@google.com (Somnath Banerjee)

#include "src/dsp/dsp.h"

#if defined(WEBP_USE_NEON)

#include <assert.h>

#include <arm_neon.h>

#include <string.h>

#include "src/dsp/neon.h"

#include "src/dsp/yuv.h"

#ifdef FANCY_UPSAMPLING

//-----------------------------------------------------------------------------

// U/V upsampling

// Loads 9 pixels each from rows r1 and r2 and generates 16 pixels.

#define UPSAMPLE_16PIXELS(r1, r2, out) do {                             \

  const uint8x8_t a = vld1_u8(r1 + 0);                                  \

  const uint8x8_t b = vld1_u8(r1 + 1);                                  \

  const uint8x8_t c = vld1_u8(r2 + 0);                                  \

  const uint8x8_t d = vld1_u8(r2 + 1);                                  \

  /* a + b + c + d */                                                   \

  const uint16x8_t ad = vaddl_u8(a,  d);                                \

  const uint16x8_t bc = vaddl_u8(b,  c);                                \

  const uint16x8_t abcd = vaddq_u16(ad, bc);                            \

  /* 3a +  b +  c + 3d */                                               \

  const uint16x8_t al = vaddq_u16(abcd, vshlq_n_u16(ad, 1));            \

  /*  a + 3b + 3c +  d */                                               \

  const uint16x8_t bl = vaddq_u16(abcd, vshlq_n_u16(bc, 1));            \

                                                                        \

  const uint8x8_t diag2 = vshrn_n_u16(al, 3);                           \

  const uint8x8_t diag1 = vshrn_n_u16(bl, 3);                           \

                                                                        \

  const uint8x8_t A = vrhadd_u8(a, diag1);                              \

  const uint8x8_t B = vrhadd_u8(b, diag2);                              \

  const uint8x8_t C = vrhadd_u8(c, diag2);                              \

  const uint8x8_t D = vrhadd_u8(d, diag1);                              \

                                                                        \

  uint8x8x2_t A_B, C_D;                                                 \

  INIT_VECTOR2(A_B, A, B);                                              \

  INIT_VECTOR2(C_D, C, D);                                              \

  vst2_u8(out +  0, A_B);                                               \

  vst2_u8(out + 32, C_D);                                               \

} while (0)

// Turn the macro into a function for reducing code-size when non-critical

static void Upsample16Pixels_NEON(const uint8_t *r1, const uint8_t *r2,

                                  uint8_t *out) {

  UPSAMPLE_16PIXELS(r1, r2, out);

}

#define UPSAMPLE_LAST_BLOCK(tb, bb, num_pixels, out) {                  \

  uint8_t r1[9], r2[9];                                                 \

  memcpy(r1, (tb), (num_pixels));                                       \

  memcpy(r2, (bb), (num_pixels));                                       \

  /* replicate last byte */                                             \

  memset(r1 + (num_pixels), r1[(num_pixels) - 1], 9 - (num_pixels));    \

  memset(r2 + (num_pixels), r2[(num_pixels) - 1], 9 - (num_pixels));    \

  Upsample16Pixels_NEON(r1, r2, out);                                   \

}

//-----------------------------------------------------------------------------

// YUV->RGB conversion

// note: we represent the 33050 large constant as 32768 + 282

static const int16_t kCoeffs1[4] = { 19077, 26149, 6419, 13320 };

#define v255 vdup_n_u8(255)

#define STORE_Rgb(out, r, g, b) do {                                    \

  uint8x8x3_t r_g_b;                                                    \

  INIT_VECTOR3(r_g_b, r, g, b);                                         \

  vst3_u8(out, r_g_b);                                                  \

} while (0)

#define STORE_Bgr(out, r, g, b) do {                                    \

  uint8x8x3_t b_g_r;                                                    \

  INIT_VECTOR3(b_g_r, b, g, r);                                         \

  vst3_u8(out, b_g_r);                                                  \

} while (0)

#define STORE_Rgba(out, r, g, b) do {                                   \

  uint8x8x4_t r_g_b_v255;                                               \

  INIT_VECTOR4(r_g_b_v255, r, g, b, v255);                              \

  vst4_u8(out, r_g_b_v255);                                             \

} while (0)

#define STORE_Bgra(out, r, g, b) do {                                   \

  uint8x8x4_t b_g_r_v255;                                               \

  INIT_VECTOR4(b_g_r_v255, b, g, r, v255);                              \

  vst4_u8(out, b_g_r_v255);                                             \

} while (0)

#define STORE_Argb(out, r, g, b) do {                                   \

  uint8x8x4_t v255_r_g_b;                                               \

  INIT_VECTOR4(v255_r_g_b, v255, r, g, b);                              \

  vst4_u8(out, v255_r_g_b);                                             \

} while (0)

#if !defined(WEBP_SWAP_16BIT_CSP)

#define ZIP_U8(lo, hi) vzip_u8((lo), (hi))

#else

#define ZIP_U8(lo, hi) vzip_u8((hi), (lo))

#endif

#define STORE_Rgba4444(out, r, g, b) do {                               \

  const uint8x8_t rg = vsri_n_u8(r, g, 4);      /* shift g, insert r */ \

  const uint8x8_t ba = vsri_n_u8(b, v255, 4);   /* shift a, insert b */ \

  const uint8x8x2_t rgba4444 = ZIP_U8(rg, ba);                          \

  vst1q_u8(out, vcombine_u8(rgba4444.val[0], rgba4444.val[1]));         \

} while (0)

#define STORE_Rgb565(out, r, g, b) do {                                 \

  const uint8x8_t rg = vsri_n_u8(r, g, 5);   /* shift g and insert r */ \

  const uint8x8_t g1 = vshl_n_u8(g, 3);      /* pre-shift g: 3bits */   \

  const uint8x8_t gb = vsri_n_u8(g1, b, 3);  /* shift b and insert g */ \

  const uint8x8x2_t rgb565 = ZIP_U8(rg, gb);                            \

  vst1q_u8(out, vcombine_u8(rgb565.val[0], rgb565.val[1]));             \

} while (0)

#define CONVERT8(FMT, XSTEP, N, src_y, src_uv, out, cur_x) do {         \

  int i;                                                                \

  for (i = 0; i < N; i += 8) {                                          \

    const int off = ((cur_x) + i) * XSTEP;                              \

    const uint8x8_t y  = vld1_u8((src_y) + (cur_x)  + i);               \

    const uint8x8_t u  = vld1_u8((src_uv) + i +  0);                    \

    const uint8x8_t v  = vld1_u8((src_uv) + i + 16);                    \

    const int16x8_t Y0 = vreinterpretq_s16_u16(vshll_n_u8(y, 7));       \

    const int16x8_t U0 = vreinterpretq_s16_u16(vshll_n_u8(u, 7));       \

    const int16x8_t V0 = vreinterpretq_s16_u16(vshll_n_u8(v, 7));       \

    const int16x8_t Y1 = vqdmulhq_lane_s16(Y0, coeff1, 0);              \

    const int16x8_t R0 = vqdmulhq_lane_s16(V0, coeff1, 1);              \

    const int16x8_t G0 = vqdmulhq_lane_s16(U0, coeff1, 2);              \

    const int16x8_t G1 = vqdmulhq_lane_s16(V0, coeff1, 3);              \

    const int16x8_t B0 = vqdmulhq_n_s16(U0, 282);                       \

    const int16x8_t R1 = vqaddq_s16(Y1, R_Rounder);                     \

    const int16x8_t G2 = vqaddq_s16(Y1, G_Rounder);                     \

    const int16x8_t B1 = vqaddq_s16(Y1, B_Rounder);                     \

    const int16x8_t R2 = vqaddq_s16(R0, R1);                            \

    const int16x8_t G3 = vqaddq_s16(G0, G1);                            \

    const int16x8_t B2 = vqaddq_s16(B0, B1);                            \

    const int16x8_t G4 = vqsubq_s16(G2, G3);                            \

    const int16x8_t B3 = vqaddq_s16(B2, U0);                            \

    const uint8x8_t R = vqshrun_n_s16(R2, YUV_FIX2);                    \

    const uint8x8_t G = vqshrun_n_s16(G4, YUV_FIX2);                    \

    const uint8x8_t B = vqshrun_n_s16(B3, YUV_FIX2);                    \

    STORE_ ## FMT(out + off, R, G, B);                                  \

  }                                                                     \

} while (0)

#define CONVERT1(FUNC, XSTEP, N, src_y, src_uv, rgb, cur_x) {           \

  int i;                                                                \

  for (i = 0; i < N; i++) {                                             \

    const int off = ((cur_x) + i) * XSTEP;                              \

    const int y = src_y[(cur_x) + i];                                   \

    const int u = (src_uv)[i];                                          \

    const int v = (src_uv)[i + 16];                                     \

    FUNC(y, u, v, rgb + off);                                           \

  }                                                                     \

}

#define CONVERT2RGB_8(FMT, XSTEP, top_y, bottom_y, uv,                  \

                      top_dst, bottom_dst, cur_x, len) {                \

  CONVERT8(FMT, XSTEP, len, top_y, uv, top_dst, cur_x);                 \

  if (bottom_y != NULL) {                                               \

    CONVERT8(FMT, XSTEP, len, bottom_y, (uv) + 32, bottom_dst, cur_x);  \

  }                                                                     \

}

#define CONVERT2RGB_1(FUNC, XSTEP, top_y, bottom_y, uv,                 \

                      top_dst, bottom_dst, cur_x, len) {                \

  CONVERT1(FUNC, XSTEP, len, top_y, uv, top_dst, cur_x);                \

  if (bottom_y != NULL) {                                               \

    CONVERT1(FUNC, XSTEP, len, bottom_y, (uv) + 32, bottom_dst, cur_x); \

  }                                                                     \

}

#define NEON_UPSAMPLE_FUNC(FUNC_NAME, FMT, XSTEP)                       \

static void FUNC_NAME(const uint8_t *top_y, const uint8_t *bottom_y,    \

                      const uint8_t *top_u, const uint8_t *top_v,       \

                      const uint8_t *cur_u, const uint8_t *cur_v,       \

                      uint8_t *top_dst, uint8_t *bottom_dst, int len) { \

  int block;                                                            \

  /* 16 byte aligned array to cache reconstructed u and v */            \

  uint8_t uv_buf[2 * 32 + 15];                                          \

  uint8_t *const r_uv = (uint8_t*)((uintptr_t)(uv_buf + 15) & ~15);     \

  const int uv_len = (len + 1) >> 1;                                    \

  /* 9 pixels must be read-able for each block */                       \

  const int num_blocks = (uv_len - 1) >> 3;                             \

  const int leftover = uv_len - num_blocks * 8;                         \

  const int last_pos = 1 + 16 * num_blocks;                             \

                                                                        \

  const int u_diag = ((top_u[0] + cur_u[0]) >> 1) + 1;                  \

  const int v_diag = ((top_v[0] + cur_v[0]) >> 1) + 1;                  \

                                                                        \

  const int16x4_t coeff1 = vld1_s16(kCoeffs1);                          \

  const int16x8_t R_Rounder = vdupq_n_s16(-14234);                      \

  const int16x8_t G_Rounder = vdupq_n_s16(8708);                        \

  const int16x8_t B_Rounder = vdupq_n_s16(-17685);                      \

                                                                        \

  /* Treat the first pixel in regular way */                            \

  assert(top_y != NULL);                                                \

  {                                                                     \

    const int u0 = (top_u[0] + u_diag) >> 1;                            \

    const int v0 = (top_v[0] + v_diag) >> 1;                            \

    VP8YuvTo ## FMT(top_y[0], u0, v0, top_dst);                         \

  }                                                                     \

  if (bottom_y != NULL) {                                               \

    const int u0 = (cur_u[0] + u_diag) >> 1;                            \

    const int v0 = (cur_v[0] + v_diag) >> 1;                            \

    VP8YuvTo ## FMT(bottom_y[0], u0, v0, bottom_dst);                   \

  }                                                                     \

                                                                        \

  for (block = 0; block < num_blocks; ++block) {                        \

    UPSAMPLE_16PIXELS(top_u, cur_u, r_uv);                              \

    UPSAMPLE_16PIXELS(top_v, cur_v, r_uv + 16);                         \

    CONVERT2RGB_8(FMT, XSTEP, top_y, bottom_y, r_uv,                    \

                  top_dst, bottom_dst, 16 * block + 1, 16);             \

    top_u += 8;                                                         \

    cur_u += 8;                                                         \

    top_v += 8;                                                         \

    cur_v += 8;                                                         \

  }                                                                     \

                                                                        \

  UPSAMPLE_LAST_BLOCK(top_u, cur_u, leftover, r_uv);                    \

  UPSAMPLE_LAST_BLOCK(top_v, cur_v, leftover, r_uv + 16);               \

  CONVERT2RGB_1(VP8YuvTo ## FMT, XSTEP, top_y, bottom_y, r_uv,          \

                top_dst, bottom_dst, last_pos, len - last_pos);         \

}

// NEON variants of the fancy upsampler.

NEON_UPSAMPLE_FUNC(UpsampleRgbaLinePair_NEON, Rgba, 4)

NEON_UPSAMPLE_FUNC(UpsampleBgraLinePair_NEON, Bgra, 4)

#if !defined(WEBP_REDUCE_CSP)

NEON_UPSAMPLE_FUNC(UpsampleRgbLinePair_NEON,  Rgb,  3)

NEON_UPSAMPLE_FUNC(UpsampleBgrLinePair_NEON,  Bgr,  3)

NEON_UPSAMPLE_FUNC(UpsampleArgbLinePair_NEON, Argb, 4)

NEON_UPSAMPLE_FUNC(UpsampleRgba4444LinePair_NEON, Rgba4444, 2)

NEON_UPSAMPLE_FUNC(UpsampleRgb565LinePair_NEON, Rgb565, 2)

#endif   // WEBP_REDUCE_CSP

//------------------------------------------------------------------------------

// Entry point

extern WebPUpsampleLinePairFunc WebPUpsamplers[/* MODE_LAST */];

extern void WebPInitUpsamplersNEON(void);

WEBP_TSAN_IGNORE_FUNCTION void WebPInitUpsamplersNEON(void) {

  WebPUpsamplers[MODE_RGBA] = UpsampleRgbaLinePair_NEON;

  WebPUpsamplers[MODE_BGRA] = UpsampleBgraLinePair_NEON;

  WebPUpsamplers[MODE_rgbA] = UpsampleRgbaLinePair_NEON;

  WebPUpsamplers[MODE_bgrA] = UpsampleBgraLinePair_NEON;

#if !defined(WEBP_REDUCE_CSP)

  WebPUpsamplers[MODE_RGB]  = UpsampleRgbLinePair_NEON;

  WebPUpsamplers[MODE_BGR]  = UpsampleBgrLinePair_NEON;

  WebPUpsamplers[MODE_ARGB] = UpsampleArgbLinePair_NEON;

  WebPUpsamplers[MODE_Argb] = UpsampleArgbLinePair_NEON;

  WebPUpsamplers[MODE_RGB_565] = UpsampleRgb565LinePair_NEON;

  WebPUpsamplers[MODE_RGBA_4444] = UpsampleRgba4444LinePair_NEON;

  WebPUpsamplers[MODE_rgbA_4444] = UpsampleRgba4444LinePair_NEON;

#endif   // WEBP_REDUCE_CSP

}

#endif  // FANCY_UPSAMPLING

#endif  // WEBP_USE_NEON

#if !(defined(FANCY_UPSAMPLING) && defined(WEBP_USE_NEON))

WEBP_DSP_INIT_STUB(WebPInitUpsamplersNEON)

#endif