Merge pull request #1238 from dimag0g/master

Add libwebp NEON-specific files

4 files changed, 814 insertions, 0 deletions

diff --git a/media/libwebp/dsp/alpha_processing_neon.c b/media/libwebp/dsp/alpha_processing_neon.c
new file mode 100644
index 000000000..53dfce2b3
--- /dev/null
+++ b/media/libwebp/dsp/alpha_processing_neon.c
@@ -0,0 +1,191 @@
+// Copyright 2017 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.
+// -----------------------------------------------------------------------------
+//
+// Utilities for processing transparent channel, NEON version.
+//
+// Author: Skal (pascal.massimino@gmail.com)
+
+#include "../dsp/dsp.h"
+
+#if defined(WEBP_USE_NEON)
+
+#include "../dsp/neon.h"
+
+//------------------------------------------------------------------------------
+
+#define MULTIPLIER(a) ((a) * 0x8081)
+#define PREMULTIPLY(x, m) (((x) * (m)) >> 23)
+
+#define MULTIPLY_BY_ALPHA(V, ALPHA, OTHER) do {                        \
+  const uint8x8_t alpha = (V).val[(ALPHA)];                            \
+  const uint16x8_t r1 = vmull_u8((V).val[1], alpha);                   \
+  const uint16x8_t g1 = vmull_u8((V).val[2], alpha);                   \
+  const uint16x8_t b1 = vmull_u8((V).val[(OTHER)], alpha);             \
+  /* we use: v / 255 = (v + 1 + (v >> 8)) >> 8 */                      \
+  const uint16x8_t r2 = vsraq_n_u16(r1, r1, 8);                        \
+  const uint16x8_t g2 = vsraq_n_u16(g1, g1, 8);                        \
+  const uint16x8_t b2 = vsraq_n_u16(b1, b1, 8);                        \
+  const uint16x8_t r3 = vaddq_u16(r2, kOne);                           \
+  const uint16x8_t g3 = vaddq_u16(g2, kOne);                           \
+  const uint16x8_t b3 = vaddq_u16(b2, kOne);                           \
+  (V).val[1] = vshrn_n_u16(r3, 8);                                     \
+  (V).val[2] = vshrn_n_u16(g3, 8);                                     \
+  (V).val[(OTHER)] = vshrn_n_u16(b3, 8);                               \
+} while (0)
+
+static void ApplyAlphaMultiply_NEON(uint8_t* rgba, int alpha_first,
+                                    int w, int h, int stride) {
+  const uint16x8_t kOne = vdupq_n_u16(1u);
+  while (h-- > 0) {
+    uint32_t* const rgbx = (uint32_t*)rgba;
+    int i = 0;
+    if (alpha_first) {
+      for (; i + 8 <= w; i += 8) {
+        // load aaaa...|rrrr...|gggg...|bbbb...
+        uint8x8x4_t RGBX = vld4_u8((const uint8_t*)(rgbx + i));
+        MULTIPLY_BY_ALPHA(RGBX, 0, 3);
+        vst4_u8((uint8_t*)(rgbx + i), RGBX);
+      }
+    } else {
+      for (; i + 8 <= w; i += 8) {
+        uint8x8x4_t RGBX = vld4_u8((const uint8_t*)(rgbx + i));
+        MULTIPLY_BY_ALPHA(RGBX, 3, 0);
+        vst4_u8((uint8_t*)(rgbx + i), RGBX);
+      }
+    }
+    // Finish with left-overs.
+    for (; i < w; ++i) {
+      uint8_t* const rgb = rgba + (alpha_first ? 1 : 0);
+      const uint8_t* const alpha = rgba + (alpha_first ? 0 : 3);
+      const uint32_t a = alpha[4 * i];
+      if (a != 0xff) {
+        const uint32_t mult = MULTIPLIER(a);
+        rgb[4 * i + 0] = PREMULTIPLY(rgb[4 * i + 0], mult);
+        rgb[4 * i + 1] = PREMULTIPLY(rgb[4 * i + 1], mult);
+        rgb[4 * i + 2] = PREMULTIPLY(rgb[4 * i + 2], mult);
+      }
+    }
+    rgba += stride;
+  }
+}
+#undef MULTIPLY_BY_ALPHA
+#undef MULTIPLIER
+#undef PREMULTIPLY
+
+//------------------------------------------------------------------------------
+
+static int DispatchAlpha_NEON(const uint8_t* alpha, int alpha_stride,
+                              int width, int height,
+                              uint8_t* dst, int dst_stride) {
+  uint32_t alpha_mask = 0xffffffffu;
+  uint8x8_t mask8 = vdup_n_u8(0xff);
+  uint32_t tmp[2];
+  int i, j;
+  for (j = 0; j < height; ++j) {
+    // We don't know if alpha is first or last in dst[] (depending on rgbA/Argb
+    // mode). So we must be sure dst[4*i + 8 - 1] is writable for the store.
+    // Hence the test with 'width - 1' instead of just 'width'.
+    for (i = 0; i + 8 <= width - 1; i += 8) {
+      uint8x8x4_t rgbX = vld4_u8((const uint8_t*)(dst + 4 * i));
+      const uint8x8_t alphas = vld1_u8(alpha + i);
+      rgbX.val[0] = alphas;
+      vst4_u8((uint8_t*)(dst + 4 * i), rgbX);
+      mask8 = vand_u8(mask8, alphas);
+    }
+    for (; i < width; ++i) {
+      const uint32_t alpha_value = alpha[i];
+      dst[4 * i] = alpha_value;
+      alpha_mask &= alpha_value;
+    }
+    alpha += alpha_stride;
+    dst += dst_stride;
+  }
+  vst1_u8((uint8_t*)tmp, mask8);
+  alpha_mask &= tmp[0];
+  alpha_mask &= tmp[1];
+  return (alpha_mask != 0xffffffffu);
+}
+
+static void DispatchAlphaToGreen_NEON(const uint8_t* alpha, int alpha_stride,
+                                      int width, int height,
+                                      uint32_t* dst, int dst_stride) {
+  int i, j;
+  uint8x8x4_t greens;   // leave A/R/B channels zero'd.
+  greens.val[0] = vdup_n_u8(0);
+  greens.val[2] = vdup_n_u8(0);
+  greens.val[3] = vdup_n_u8(0);
+  for (j = 0; j < height; ++j) {
+    for (i = 0; i + 8 <= width; i += 8) {
+      greens.val[1] = vld1_u8(alpha + i);
+      vst4_u8((uint8_t*)(dst + i), greens);
+    }
+    for (; i < width; ++i) dst[i] = alpha[i] << 8;
+    alpha += alpha_stride;
+    dst += dst_stride;
+  }
+}
+
+static int ExtractAlpha_NEON(const uint8_t* argb, int argb_stride,
+                             int width, int height,
+                             uint8_t* alpha, int alpha_stride) {
+  uint32_t alpha_mask = 0xffffffffu;
+  uint8x8_t mask8 = vdup_n_u8(0xff);
+  uint32_t tmp[2];
+  int i, j;
+  for (j = 0; j < height; ++j) {
+    // We don't know if alpha is first or last in dst[] (depending on rgbA/Argb
+    // mode). So we must be sure dst[4*i + 8 - 1] is writable for the store.
+    // Hence the test with 'width - 1' instead of just 'width'.
+    for (i = 0; i + 8 <= width - 1; i += 8) {
+      const uint8x8x4_t rgbX = vld4_u8((const uint8_t*)(argb + 4 * i));
+      const uint8x8_t alphas = rgbX.val[0];
+      vst1_u8((uint8_t*)(alpha + i), alphas);
+      mask8 = vand_u8(mask8, alphas);
+    }
+    for (; i < width; ++i) {
+      alpha[i] = argb[4 * i];
+      alpha_mask &= alpha[i];
+    }
+    argb += argb_stride;
+    alpha += alpha_stride;
+  }
+  vst1_u8((uint8_t*)tmp, mask8);
+  alpha_mask &= tmp[0];
+  alpha_mask &= tmp[1];
+  return (alpha_mask == 0xffffffffu);
+}
+
+static void ExtractGreen_NEON(const uint32_t* argb,
+                              uint8_t* alpha, int size) {
+  int i;
+  for (i = 0; i + 16 <= size; i += 16) {
+    const uint8x16x4_t rgbX = vld4q_u8((const uint8_t*)(argb + i));
+    const uint8x16_t greens = rgbX.val[1];
+    vst1q_u8(alpha + i, greens);
+  }
+  for (; i < size; ++i) alpha[i] = (argb[i] >> 8) & 0xff;
+}
+
+//------------------------------------------------------------------------------
+
+extern void WebPInitAlphaProcessingNEON(void);
+
+WEBP_TSAN_IGNORE_FUNCTION void WebPInitAlphaProcessingNEON(void) {
+  WebPApplyAlphaMultiply = ApplyAlphaMultiply_NEON;
+  WebPDispatchAlpha = DispatchAlpha_NEON;
+  WebPDispatchAlphaToGreen = DispatchAlphaToGreen_NEON;
+  WebPExtractAlpha = ExtractAlpha_NEON;
+  WebPExtractGreen = ExtractGreen_NEON;
+}
+
+#else  // !WEBP_USE_NEON
+
+WEBP_DSP_INIT_STUB(WebPInitAlphaProcessingNEON)
+
+#endif  // WEBP_USE_NEON
diff --git a/media/libwebp/dsp/filters_neon.c b/media/libwebp/dsp/filters_neon.c
new file mode 100644
index 000000000..4788118c9
--- /dev/null
+++ b/media/libwebp/dsp/filters_neon.c
@@ -0,0 +1,329 @@
+// Copyright 2017 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 variant of alpha filters
+//
+// Author: Skal (pascal.massimino@gmail.com)
+
+#include "../dsp/dsp.h"
+
+#if defined(WEBP_USE_NEON)
+
+#include <assert.h>
+#include "../dsp/neon.h"
+
+//------------------------------------------------------------------------------
+// Helpful macros.
+
+# define SANITY_CHECK(in, out)                                                 \
+  assert(in != NULL);                                                          \
+  assert(out != NULL);                                                         \
+  assert(width > 0);                                                           \
+  assert(height > 0);                                                          \
+  assert(stride >= width);                                                     \
+  assert(row >= 0 && num_rows > 0 && row + num_rows <= height);                \
+  (void)height;  // Silence unused warning.
+
+// load eight u8 and widen to s16
+#define U8_TO_S16(A) vreinterpretq_s16_u16(vmovl_u8(A))
+#define LOAD_U8_TO_S16(A) U8_TO_S16(vld1_u8(A))
+
+// shift left or right by N byte, inserting zeros
+#define SHIFT_RIGHT_N_Q(A, N) vextq_u8((A), zero, (N))
+#define SHIFT_LEFT_N_Q(A, N) vextq_u8(zero, (A), (16 - (N)) % 16)
+
+// rotate left by N bytes
+#define ROTATE_LEFT_N(A, N)   vext_u8((A), (A), (N))
+// rotate right by N bytes
+#define ROTATE_RIGHT_N(A, N)   vext_u8((A), (A), (8 - (N)) % 8)
+
+static void PredictLine_NEON(const uint8_t* src, const uint8_t* pred,
+                             uint8_t* dst, int length) {
+  int i;
+  assert(length >= 0);
+  for (i = 0; i + 16 <= length; i += 16) {
+    const uint8x16_t A = vld1q_u8(&src[i]);
+    const uint8x16_t B = vld1q_u8(&pred[i]);
+    const uint8x16_t C = vsubq_u8(A, B);
+    vst1q_u8(&dst[i], C);
+  }
+  for (; i < length; ++i) dst[i] = src[i] - pred[i];
+}
+
+// Special case for left-based prediction (when preds==dst-1 or preds==src-1).
+static void PredictLineLeft_NEON(const uint8_t* src, uint8_t* dst, int length) {
+  PredictLine_NEON(src, src - 1, dst, length);
+}
+
+//------------------------------------------------------------------------------
+// Horizontal filter.
+
+static WEBP_INLINE void DoHorizontalFilter_NEON(const uint8_t* in,
+                                                int width, int height,
+                                                int stride,
+                                                int row, int num_rows,
+                                                uint8_t* out) {
+  const size_t start_offset = row * stride;
+  const int last_row = row + num_rows;
+  SANITY_CHECK(in, out);
+  in += start_offset;
+  out += start_offset;
+
+  if (row == 0) {
+    // Leftmost pixel is the same as input for topmost scanline.
+    out[0] = in[0];
+    PredictLineLeft_NEON(in + 1, out + 1, width - 1);
+    row = 1;
+    in += stride;
+    out += stride;
+  }
+
+  // Filter line-by-line.
+  while (row < last_row) {
+    // Leftmost pixel is predicted from above.
+    out[0] = in[0] - in[-stride];
+    PredictLineLeft_NEON(in + 1, out + 1, width - 1);
+    ++row;
+    in += stride;
+    out += stride;
+  }
+}
+
+static void HorizontalFilter_NEON(const uint8_t* data, int width, int height,
+                                  int stride, uint8_t* filtered_data) {
+  DoHorizontalFilter_NEON(data, width, height, stride, 0, height,
+                          filtered_data);
+}
+
+//------------------------------------------------------------------------------
+// Vertical filter.
+
+static WEBP_INLINE void DoVerticalFilter_NEON(const uint8_t* in,
+                                              int width, int height, int stride,
+                                              int row, int num_rows,
+                                              uint8_t* out) {
+  const size_t start_offset = row * stride;
+  const int last_row = row + num_rows;
+  SANITY_CHECK(in, out);
+  in += start_offset;
+  out += start_offset;
+
+  if (row == 0) {
+    // Very first top-left pixel is copied.
+    out[0] = in[0];
+    // Rest of top scan-line is left-predicted.
+    PredictLineLeft_NEON(in + 1, out + 1, width - 1);
+    row = 1;
+    in += stride;
+    out += stride;
+  }
+
+  // Filter line-by-line.
+  while (row < last_row) {
+    PredictLine_NEON(in, in - stride, out, width);
+    ++row;
+    in += stride;
+    out += stride;
+  }
+}
+
+static void VerticalFilter_NEON(const uint8_t* data, int width, int height,
+                                int stride, uint8_t* filtered_data) {
+  DoVerticalFilter_NEON(data, width, height, stride, 0, height,
+                        filtered_data);
+}
+
+//------------------------------------------------------------------------------
+// Gradient filter.
+
+static WEBP_INLINE int GradientPredictor_C(uint8_t a, uint8_t b, uint8_t c) {
+  const int g = a + b - c;
+  return ((g & ~0xff) == 0) ? g : (g < 0) ? 0 : 255;  // clip to 8bit
+}
+
+static void GradientPredictDirect_NEON(const uint8_t* const row,
+                                       const uint8_t* const top,
+                                       uint8_t* const out, int length) {
+  int i;
+  for (i = 0; i + 8 <= length; i += 8) {
+    const uint8x8_t A = vld1_u8(&row[i - 1]);
+    const uint8x8_t B = vld1_u8(&top[i + 0]);
+    const int16x8_t C = vreinterpretq_s16_u16(vaddl_u8(A, B));
+    const int16x8_t D = LOAD_U8_TO_S16(&top[i - 1]);
+    const uint8x8_t E = vqmovun_s16(vsubq_s16(C, D));
+    const uint8x8_t F = vld1_u8(&row[i + 0]);
+    vst1_u8(&out[i], vsub_u8(F, E));
+  }
+  for (; i < length; ++i) {
+    out[i] = row[i] - GradientPredictor_C(row[i - 1], top[i], top[i - 1]);
+  }
+}
+
+static WEBP_INLINE void DoGradientFilter_NEON(const uint8_t* in,
+                                              int width, int height,
+                                              int stride,
+                                              int row, int num_rows,
+                                              uint8_t* out) {
+  const size_t start_offset = row * stride;
+  const int last_row = row + num_rows;
+  SANITY_CHECK(in, out);
+  in += start_offset;
+  out += start_offset;
+
+  // left prediction for top scan-line
+  if (row == 0) {
+    out[0] = in[0];
+    PredictLineLeft_NEON(in + 1, out + 1, width - 1);
+    row = 1;
+    in += stride;
+    out += stride;
+  }
+
+  // Filter line-by-line.
+  while (row < last_row) {
+    out[0] = in[0] - in[-stride];
+    GradientPredictDirect_NEON(in + 1, in + 1 - stride, out + 1, width - 1);
+    ++row;
+    in += stride;
+    out += stride;
+  }
+}
+
+static void GradientFilter_NEON(const uint8_t* data, int width, int height,
+                                int stride, uint8_t* filtered_data) {
+  DoGradientFilter_NEON(data, width, height, stride, 0, height,
+                        filtered_data);
+}
+
+#undef SANITY_CHECK
+
+//------------------------------------------------------------------------------
+// Inverse transforms
+
+static void HorizontalUnfilter_NEON(const uint8_t* prev, const uint8_t* in,
+                                    uint8_t* out, int width) {
+  int i;
+  const uint8x16_t zero = vdupq_n_u8(0);
+  uint8x16_t last;
+  out[0] = in[0] + (prev == NULL ? 0 : prev[0]);
+  if (width <= 1) return;
+  last = vsetq_lane_u8(out[0], zero, 0);
+  for (i = 1; i + 16 <= width; i += 16) {
+    const uint8x16_t A0 = vld1q_u8(&in[i]);
+    const uint8x16_t A1 = vaddq_u8(A0, last);
+    const uint8x16_t A2 = SHIFT_LEFT_N_Q(A1, 1);
+    const uint8x16_t A3 = vaddq_u8(A1, A2);
+    const uint8x16_t A4 = SHIFT_LEFT_N_Q(A3, 2);
+    const uint8x16_t A5 = vaddq_u8(A3, A4);
+    const uint8x16_t A6 = SHIFT_LEFT_N_Q(A5, 4);
+    const uint8x16_t A7 = vaddq_u8(A5, A6);
+    const uint8x16_t A8 = SHIFT_LEFT_N_Q(A7, 8);
+    const uint8x16_t A9 = vaddq_u8(A7, A8);
+    vst1q_u8(&out[i], A9);
+    last = SHIFT_RIGHT_N_Q(A9, 15);
+  }
+  for (; i < width; ++i) out[i] = in[i] + out[i - 1];
+}
+
+static void VerticalUnfilter_NEON(const uint8_t* prev, const uint8_t* in,
+                                  uint8_t* out, int width) {
+  if (prev == NULL) {
+    HorizontalUnfilter_NEON(NULL, in, out, width);
+  } else {
+    int i;
+    assert(width >= 0);
+    for (i = 0; i + 16 <= width; i += 16) {
+      const uint8x16_t A = vld1q_u8(&in[i]);
+      const uint8x16_t B = vld1q_u8(&prev[i]);
+      const uint8x16_t C = vaddq_u8(A, B);
+      vst1q_u8(&out[i], C);
+    }
+    for (; i < width; ++i) out[i] = in[i] + prev[i];
+  }
+}
+
+// GradientUnfilter_NEON is correct but slower than the C-version,
+// at least on ARM64. For armv7, it's a wash.
+// So best is to disable it for now, but keep the idea around...
+#if !defined(USE_GRADIENT_UNFILTER)
+#define USE_GRADIENT_UNFILTER 0   // ALTERNATE_CODE
+#endif
+
+#if (USE_GRADIENT_UNFILTER == 1)
+#define GRAD_PROCESS_LANE(L)  do {                                             \
+  const uint8x8_t tmp1 = ROTATE_RIGHT_N(pred, 1);  /* rotate predictor in */   \
+  const int16x8_t tmp2 = vaddq_s16(BC, U8_TO_S16(tmp1));                       \
+  const uint8x8_t delta = vqmovun_s16(tmp2);                                   \
+  pred = vadd_u8(D, delta);                                                    \
+  out = vext_u8(out, ROTATE_LEFT_N(pred, (L)), 1);                             \
+} while (0)
+
+static void GradientPredictInverse_NEON(const uint8_t* const in,
+                                        const uint8_t* const top,
+                                        uint8_t* const row, int length) {
+  if (length > 0) {
+    int i;
+    uint8x8_t pred = vdup_n_u8(row[-1]);   // left sample
+    uint8x8_t out = vdup_n_u8(0);
+    for (i = 0; i + 8 <= length; i += 8) {
+      const int16x8_t B = LOAD_U8_TO_S16(&top[i + 0]);
+      const int16x8_t C = LOAD_U8_TO_S16(&top[i - 1]);
+      const int16x8_t BC = vsubq_s16(B, C);  // unclipped gradient basis B - C
+      const uint8x8_t D = vld1_u8(&in[i]);   // base input
+      GRAD_PROCESS_LANE(0);
+      GRAD_PROCESS_LANE(1);
+      GRAD_PROCESS_LANE(2);
+      GRAD_PROCESS_LANE(3);
+      GRAD_PROCESS_LANE(4);
+      GRAD_PROCESS_LANE(5);
+      GRAD_PROCESS_LANE(6);
+      GRAD_PROCESS_LANE(7);
+      vst1_u8(&row[i], out);
+    }
+    for (; i < length; ++i) {
+      row[i] = in[i] + GradientPredictor_C(row[i - 1], top[i], top[i - 1]);
+    }
+  }
+}
+#undef GRAD_PROCESS_LANE
+
+static void GradientUnfilter_NEON(const uint8_t* prev, const uint8_t* in,
+                                  uint8_t* out, int width) {
+  if (prev == NULL) {
+    HorizontalUnfilter_NEON(NULL, in, out, width);
+  } else {
+    out[0] = in[0] + prev[0];  // predict from above
+    GradientPredictInverse_NEON(in + 1, prev + 1, out + 1, width - 1);
+  }
+}
+
+#endif   // USE_GRADIENT_UNFILTER
+
+//------------------------------------------------------------------------------
+// Entry point
+
+extern void VP8FiltersInitNEON(void);
+
+WEBP_TSAN_IGNORE_FUNCTION void VP8FiltersInitNEON(void) {
+  WebPUnfilters[WEBP_FILTER_HORIZONTAL] = HorizontalUnfilter_NEON;
+  WebPUnfilters[WEBP_FILTER_VERTICAL] = VerticalUnfilter_NEON;
+#if (USE_GRADIENT_UNFILTER == 1)
+  WebPUnfilters[WEBP_FILTER_GRADIENT] = GradientUnfilter_NEON;
+#endif
+
+  WebPFilters[WEBP_FILTER_HORIZONTAL] = HorizontalFilter_NEON;
+  WebPFilters[WEBP_FILTER_VERTICAL] = VerticalFilter_NEON;
+  WebPFilters[WEBP_FILTER_GRADIENT] = GradientFilter_NEON;
+}
+
+#else  // !WEBP_USE_NEON
+
+WEBP_DSP_INIT_STUB(VP8FiltersInitNEON)
+
+#endif  // WEBP_USE_NEON
diff --git a/media/libwebp/dsp/moz.build b/media/libwebp/dsp/moz.build
index fa6df9e9e..f3c2bdd0b 100644
--- a/media/libwebp/dsp/moz.build
+++ b/media/libwebp/dsp/moz.build
@@ -9,6 +9,7 @@ with Files('**'):
 
 SOURCES += [
     'alpha_processing.c',
+    'alpha_processing_neon.c',
     'alpha_processing_sse2.c',
     'alpha_processing_sse41.c',
     'dec.c',
@@ -17,6 +18,7 @@ SOURCES += [
     'dec_sse2.c',
     'dec_sse41.c',
     'filters.c',
+    'filters_neon.c',
     'filters_sse2.c',
     'lossless.c',
     'lossless_neon.c',
@@ -29,15 +31,19 @@ SOURCES += [
     'upsampling_sse2.c',
     'upsampling_sse41.c',
     'yuv.c',
+    'yuv_neon.c',
     'yuv_sse2.c',
     'yuv_sse41.c',
 ]
 
 if CONFIG['CPU_ARCH'] == 'arm' and CONFIG['BUILD_ARM_NEON']:
+    SOURCES['alpha_processing_neon.c'].flags += CONFIG['NEON_FLAGS']
     SOURCES['dec_neon.c'].flags += CONFIG['NEON_FLAGS']
+    SOURCES['filters_neon.c'].flags += CONFIG['NEON_FLAGS']
     SOURCES['lossless_neon.c'].flags += CONFIG['NEON_FLAGS']
     SOURCES['rescaler_neon.c'].flags += CONFIG['NEON_FLAGS']
     SOURCES['upsampling_neon.c'].flags += CONFIG['NEON_FLAGS']
+    SOURCES['yuv_neon.c'].flags += CONFIG['NEON_FLAGS']
 elif CONFIG['INTEL_ARCHITECTURE']:
     SOURCES['alpha_processing_sse2.c'].flags += CONFIG['SSE2_FLAGS']
     SOURCES['alpha_processing_sse41.c'].flags += CONFIG['SSE2_FLAGS']
diff --git a/media/libwebp/dsp/yuv_neon.c b/media/libwebp/dsp/yuv_neon.c
new file mode 100644
index 000000000..81f00fe5a
--- /dev/null
+++ b/media/libwebp/dsp/yuv_neon.c
@@ -0,0 +1,288 @@
+// Copyright 2017 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.
+// -----------------------------------------------------------------------------
+//
+// YUV->RGB conversion functions
+//
+// Author: Skal (pascal.massimino@gmail.com)
+
+#include "../dsp/yuv.h"
+
+#if defined(WEBP_USE_NEON)
+
+#include <assert.h>
+#include <stdlib.h>
+
+#include "../dsp/neon.h"
+
+//-----------------------------------------------------------------------------
+
+static uint8x8_t ConvertRGBToY_NEON(const uint8x8_t R,
+                                    const uint8x8_t G,
+                                    const uint8x8_t B) {
+  const uint16x8_t r = vmovl_u8(R);
+  const uint16x8_t g = vmovl_u8(G);
+  const uint16x8_t b = vmovl_u8(B);
+  const uint16x4_t r_lo = vget_low_u16(r);
+  const uint16x4_t r_hi = vget_high_u16(r);
+  const uint16x4_t g_lo = vget_low_u16(g);
+  const uint16x4_t g_hi = vget_high_u16(g);
+  const uint16x4_t b_lo = vget_low_u16(b);
+  const uint16x4_t b_hi = vget_high_u16(b);
+  const uint32x4_t tmp0_lo = vmull_n_u16(         r_lo, 16839u);
+  const uint32x4_t tmp0_hi = vmull_n_u16(         r_hi, 16839u);
+  const uint32x4_t tmp1_lo = vmlal_n_u16(tmp0_lo, g_lo, 33059u);
+  const uint32x4_t tmp1_hi = vmlal_n_u16(tmp0_hi, g_hi, 33059u);
+  const uint32x4_t tmp2_lo = vmlal_n_u16(tmp1_lo, b_lo, 6420u);
+  const uint32x4_t tmp2_hi = vmlal_n_u16(tmp1_hi, b_hi, 6420u);
+  const uint16x8_t Y1 = vcombine_u16(vrshrn_n_u32(tmp2_lo, 16),
+                                     vrshrn_n_u32(tmp2_hi, 16));
+  const uint16x8_t Y2 = vaddq_u16(Y1, vdupq_n_u16(16));
+  return vqmovn_u16(Y2);
+}
+
+static void ConvertRGB24ToY_NEON(const uint8_t* rgb, uint8_t* y, int width) {
+  int i;
+  for (i = 0; i + 8 <= width; i += 8, rgb += 3 * 8) {
+    const uint8x8x3_t RGB = vld3_u8(rgb);
+    const uint8x8_t Y = ConvertRGBToY_NEON(RGB.val[0], RGB.val[1], RGB.val[2]);
+    vst1_u8(y + i, Y);
+  }
+  for (; i < width; ++i, rgb += 3) {   // left-over
+    y[i] = VP8RGBToY(rgb[0], rgb[1], rgb[2], YUV_HALF);
+  }
+}
+
+static void ConvertBGR24ToY_NEON(const uint8_t* bgr, uint8_t* y, int width) {
+  int i;
+  for (i = 0; i + 8 <= width; i += 8, bgr += 3 * 8) {
+    const uint8x8x3_t BGR = vld3_u8(bgr);
+    const uint8x8_t Y = ConvertRGBToY_NEON(BGR.val[2], BGR.val[1], BGR.val[0]);
+    vst1_u8(y + i, Y);
+  }
+  for (; i < width; ++i, bgr += 3) {  // left-over
+    y[i] = VP8RGBToY(bgr[2], bgr[1], bgr[0], YUV_HALF);
+  }
+}
+
+static void ConvertARGBToY_NEON(const uint32_t* argb, uint8_t* y, int width) {
+  int i;
+  for (i = 0; i + 8 <= width; i += 8) {
+    const uint8x8x4_t RGB = vld4_u8((const uint8_t*)&argb[i]);
+    const uint8x8_t Y = ConvertRGBToY_NEON(RGB.val[2], RGB.val[1], RGB.val[0]);
+    vst1_u8(y + i, Y);
+  }
+  for (; i < width; ++i) {   // left-over
+    const uint32_t p = argb[i];
+    y[i] = VP8RGBToY((p >> 16) & 0xff, (p >> 8) & 0xff, (p >>  0) & 0xff,
+                     YUV_HALF);
+  }
+}
+
+//-----------------------------------------------------------------------------
+
+// computes: DST_s16 = [(C0 * r + C1 * g + C2 * b) >> 16] + CST
+#define MULTIPLY_16b_PREAMBLE(r, g, b)                           \
+  const int16x4_t r_lo = vreinterpret_s16_u16(vget_low_u16(r));  \
+  const int16x4_t r_hi = vreinterpret_s16_u16(vget_high_u16(r)); \
+  const int16x4_t g_lo = vreinterpret_s16_u16(vget_low_u16(g));  \
+  const int16x4_t g_hi = vreinterpret_s16_u16(vget_high_u16(g)); \
+  const int16x4_t b_lo = vreinterpret_s16_u16(vget_low_u16(b));  \
+  const int16x4_t b_hi = vreinterpret_s16_u16(vget_high_u16(b))
+
+#define MULTIPLY_16b(C0, C1, C2, CST, DST_s16) do {              \
+  const int32x4_t tmp0_lo = vmull_n_s16(         r_lo, C0);      \
+  const int32x4_t tmp0_hi = vmull_n_s16(         r_hi, C0);      \
+  const int32x4_t tmp1_lo = vmlal_n_s16(tmp0_lo, g_lo, C1);      \
+  const int32x4_t tmp1_hi = vmlal_n_s16(tmp0_hi, g_hi, C1);      \
+  const int32x4_t tmp2_lo = vmlal_n_s16(tmp1_lo, b_lo, C2);      \
+  const int32x4_t tmp2_hi = vmlal_n_s16(tmp1_hi, b_hi, C2);      \
+  const int16x8_t tmp3 = vcombine_s16(vshrn_n_s32(tmp2_lo, 16),  \
+                                      vshrn_n_s32(tmp2_hi, 16)); \
+  DST_s16 = vaddq_s16(tmp3, vdupq_n_s16(CST));                   \
+} while (0)
+
+// This needs to be a macro, since (128 << SHIFT) needs to be an immediate.
+#define CONVERT_RGB_TO_UV(r, g, b, SHIFT, U_DST, V_DST) do {     \
+  MULTIPLY_16b_PREAMBLE(r, g, b);                                \
+  MULTIPLY_16b(-9719, -19081, 28800, 128 << SHIFT, U_DST);       \
+  MULTIPLY_16b(28800, -24116, -4684, 128 << SHIFT, V_DST);       \
+} while (0)
+
+static void ConvertRGBA32ToUV_NEON(const uint16_t* rgb,
+                                   uint8_t* u, uint8_t* v, int width) {
+  int i;
+  for (i = 0; i + 8 <= width; i += 8, rgb += 4 * 8) {
+    const uint16x8x4_t RGB = vld4q_u16((const uint16_t*)rgb);
+    int16x8_t U, V;
+    CONVERT_RGB_TO_UV(RGB.val[0], RGB.val[1], RGB.val[2], 2, U, V);
+    vst1_u8(u + i, vqrshrun_n_s16(U, 2));
+    vst1_u8(v + i, vqrshrun_n_s16(V, 2));
+  }
+  for (; i < width; i += 1, rgb += 4) {
+    const int r = rgb[0], g = rgb[1], b = rgb[2];
+    u[i] = VP8RGBToU(r, g, b, YUV_HALF << 2);
+    v[i] = VP8RGBToV(r, g, b, YUV_HALF << 2);
+  }
+}
+
+static void ConvertARGBToUV_NEON(const uint32_t* argb, uint8_t* u, uint8_t* v,
+                                 int src_width, int do_store) {
+  int i;
+  for (i = 0; i + 16 <= src_width; i += 16, u += 8, v += 8) {
+    const uint8x16x4_t RGB = vld4q_u8((const uint8_t*)&argb[i]);
+    const uint16x8_t R = vpaddlq_u8(RGB.val[2]);  // pair-wise adds
+    const uint16x8_t G = vpaddlq_u8(RGB.val[1]);
+    const uint16x8_t B = vpaddlq_u8(RGB.val[0]);
+    int16x8_t U_tmp, V_tmp;
+    CONVERT_RGB_TO_UV(R, G, B, 1, U_tmp, V_tmp);
+    {
+      const uint8x8_t U = vqrshrun_n_s16(U_tmp, 1);
+      const uint8x8_t V = vqrshrun_n_s16(V_tmp, 1);
+      if (do_store) {
+        vst1_u8(u, U);
+        vst1_u8(v, V);
+      } else {
+        const uint8x8_t prev_u = vld1_u8(u);
+        const uint8x8_t prev_v = vld1_u8(v);
+        vst1_u8(u, vrhadd_u8(U, prev_u));
+        vst1_u8(v, vrhadd_u8(V, prev_v));
+      }
+    }
+  }
+  if (i < src_width) {  // left-over
+    WebPConvertARGBToUV_C(argb + i, u, v, src_width - i, do_store);
+  }
+}
+
+
+//------------------------------------------------------------------------------
+
+extern void WebPInitConvertARGBToYUVNEON(void);
+
+WEBP_TSAN_IGNORE_FUNCTION void WebPInitConvertARGBToYUVNEON(void) {
+  WebPConvertRGB24ToY = ConvertRGB24ToY_NEON;
+  WebPConvertBGR24ToY = ConvertBGR24ToY_NEON;
+  WebPConvertARGBToY = ConvertARGBToY_NEON;
+  WebPConvertARGBToUV = ConvertARGBToUV_NEON;
+  WebPConvertRGBA32ToUV = ConvertRGBA32ToUV_NEON;
+}
+
+//------------------------------------------------------------------------------
+
+#define MAX_Y ((1 << 10) - 1)    // 10b precision over 16b-arithmetic
+static uint16_t clip_y_NEON(int v) {
+  return (v < 0) ? 0 : (v > MAX_Y) ? MAX_Y : (uint16_t)v;
+}
+
+static uint64_t SharpYUVUpdateY_NEON(const uint16_t* ref, const uint16_t* src,
+                                     uint16_t* dst, int len) {
+  int i;
+  const int16x8_t zero = vdupq_n_s16(0);
+  const int16x8_t max = vdupq_n_s16(MAX_Y);
+  uint64x2_t sum = vdupq_n_u64(0);
+  uint64_t diff;
+
+  for (i = 0; i + 8 <= len; i += 8) {
+    const int16x8_t A = vreinterpretq_s16_u16(vld1q_u16(ref + i));
+    const int16x8_t B = vreinterpretq_s16_u16(vld1q_u16(src + i));
+    const int16x8_t C = vreinterpretq_s16_u16(vld1q_u16(dst + i));
+    const int16x8_t D = vsubq_s16(A, B);       // diff_y
+    const int16x8_t F = vaddq_s16(C, D);       // new_y
+    const uint16x8_t H =
+        vreinterpretq_u16_s16(vmaxq_s16(vminq_s16(F, max), zero));
+    const int16x8_t I = vabsq_s16(D);          // abs(diff_y)
+    vst1q_u16(dst + i, H);
+    sum = vpadalq_u32(sum, vpaddlq_u16(vreinterpretq_u16_s16(I)));
+  }
+  diff = vgetq_lane_u64(sum, 0) + vgetq_lane_u64(sum, 1);
+  for (; i < len; ++i) {
+    const int diff_y = ref[i] - src[i];
+    const int new_y = (int)(dst[i]) + diff_y;
+    dst[i] = clip_y_NEON(new_y);
+    diff += (uint64_t)(abs(diff_y));
+  }
+  return diff;
+}
+
+static void SharpYUVUpdateRGB_NEON(const int16_t* ref, const int16_t* src,
+                                   int16_t* dst, int len) {
+  int i;
+  for (i = 0; i + 8 <= len; i += 8) {
+    const int16x8_t A = vld1q_s16(ref + i);
+    const int16x8_t B = vld1q_s16(src + i);
+    const int16x8_t C = vld1q_s16(dst + i);
+    const int16x8_t D = vsubq_s16(A, B);   // diff_uv
+    const int16x8_t E = vaddq_s16(C, D);   // new_uv
+    vst1q_s16(dst + i, E);
+  }
+  for (; i < len; ++i) {
+    const int diff_uv = ref[i] - src[i];
+    dst[i] += diff_uv;
+  }
+}
+
+static void SharpYUVFilterRow_NEON(const int16_t* A, const int16_t* B, int len,
+                                   const uint16_t* best_y, uint16_t* out) {
+  int i;
+  const int16x8_t max = vdupq_n_s16(MAX_Y);
+  const int16x8_t zero = vdupq_n_s16(0);
+  for (i = 0; i + 8 <= len; i += 8) {
+    const int16x8_t a0 = vld1q_s16(A + i + 0);
+    const int16x8_t a1 = vld1q_s16(A + i + 1);
+    const int16x8_t b0 = vld1q_s16(B + i + 0);
+    const int16x8_t b1 = vld1q_s16(B + i + 1);
+    const int16x8_t a0b1 = vaddq_s16(a0, b1);
+    const int16x8_t a1b0 = vaddq_s16(a1, b0);
+    const int16x8_t a0a1b0b1 = vaddq_s16(a0b1, a1b0);  // A0+A1+B0+B1
+    const int16x8_t a0b1_2 = vaddq_s16(a0b1, a0b1);    // 2*(A0+B1)
+    const int16x8_t a1b0_2 = vaddq_s16(a1b0, a1b0);    // 2*(A1+B0)
+    const int16x8_t c0 = vshrq_n_s16(vaddq_s16(a0b1_2, a0a1b0b1), 3);
+    const int16x8_t c1 = vshrq_n_s16(vaddq_s16(a1b0_2, a0a1b0b1), 3);
+    const int16x8_t d0 = vaddq_s16(c1, a0);
+    const int16x8_t d1 = vaddq_s16(c0, a1);
+    const int16x8_t e0 = vrshrq_n_s16(d0, 1);
+    const int16x8_t e1 = vrshrq_n_s16(d1, 1);
+    const int16x8x2_t f = vzipq_s16(e0, e1);
+    const int16x8_t g0 = vreinterpretq_s16_u16(vld1q_u16(best_y + 2 * i + 0));
+    const int16x8_t g1 = vreinterpretq_s16_u16(vld1q_u16(best_y + 2 * i + 8));
+    const int16x8_t h0 = vaddq_s16(g0, f.val[0]);
+    const int16x8_t h1 = vaddq_s16(g1, f.val[1]);
+    const int16x8_t i0 = vmaxq_s16(vminq_s16(h0, max), zero);
+    const int16x8_t i1 = vmaxq_s16(vminq_s16(h1, max), zero);
+    vst1q_u16(out + 2 * i + 0, vreinterpretq_u16_s16(i0));
+    vst1q_u16(out + 2 * i + 8, vreinterpretq_u16_s16(i1));
+  }
+  for (; i < len; ++i) {
+    const int a0b1 = A[i + 0] + B[i + 1];
+    const int a1b0 = A[i + 1] + B[i + 0];
+    const int a0a1b0b1 = a0b1 + a1b0 + 8;
+    const int v0 = (8 * A[i + 0] + 2 * a1b0 + a0a1b0b1) >> 4;
+    const int v1 = (8 * A[i + 1] + 2 * a0b1 + a0a1b0b1) >> 4;
+    out[2 * i + 0] = clip_y_NEON(best_y[2 * i + 0] + v0);
+    out[2 * i + 1] = clip_y_NEON(best_y[2 * i + 1] + v1);
+  }
+}
+#undef MAX_Y
+
+//------------------------------------------------------------------------------
+
+extern void WebPInitSharpYUVNEON(void);
+
+WEBP_TSAN_IGNORE_FUNCTION void WebPInitSharpYUVNEON(void) {
+  WebPSharpYUVUpdateY = SharpYUVUpdateY_NEON;
+  WebPSharpYUVUpdateRGB = SharpYUVUpdateRGB_NEON;
+  WebPSharpYUVFilterRow = SharpYUVFilterRow_NEON;
+}
+
+#else  // !WEBP_USE_NEON
+
+WEBP_DSP_INIT_STUB(WebPInitConvertARGBToYUVNEON)
+WEBP_DSP_INIT_STUB(WebPInitSharpYUVNEON)
+
+#endif  // WEBP_USE_NEON