libwebp: update to 0.4.1

third_party/libwebp/dsp/upsampling.c

Index: third_party/libwebp/dsp/upsampling.c
diff --git a/third_party/libwebp/dsp/upsampling.c b/third_party/libwebp/dsp/upsampling.c
index 978e3ce2509c2adcf90c0d38d48be6dce0789d59..2b1656bf9b5abd41c13f65f18045334c3bff415e 100644
--- a/third_party/libwebp/dsp/upsampling.c
+++ b/third_party/libwebp/dsp/upsampling.c
@@ -107,57 +107,6 @@ UPSAMPLE_FUNC(UpsampleRgb565LinePair,  VP8YuvToRgb565,  2)
 #endif  // FANCY_UPSAMPLING
 
 //------------------------------------------------------------------------------
-// simple point-sampling
-
-#define SAMPLE_FUNC(FUNC_NAME, FUNC, XSTEP)                                    \
-static void FUNC_NAME(const uint8_t* top_y, const uint8_t* bottom_y,           \
-                      const uint8_t* u, const uint8_t* v,                      \
-                      uint8_t* top_dst, uint8_t* bottom_dst, int len) {        \
-  int i;                                                                       \
-  for (i = 0; i < len - 1; i += 2) {                                           \
-    FUNC(top_y[0], u[0], v[0], top_dst);                                       \
-    FUNC(top_y[1], u[0], v[0], top_dst + XSTEP);                               \
-    FUNC(bottom_y[0], u[0], v[0], bottom_dst);                                 \
-    FUNC(bottom_y[1], u[0], v[0], bottom_dst + XSTEP);                         \
-    top_y += 2;                                                                \
-    bottom_y += 2;                                                             \
-    u++;                                                                       \
-    v++;                                                                       \
-    top_dst += 2 * XSTEP;                                                      \
-    bottom_dst += 2 * XSTEP;                                                   \
-  }                                                                            \
-  if (i == len - 1) {    /* last one */                                        \
-    FUNC(top_y[0], u[0], v[0], top_dst);                                       \
-    FUNC(bottom_y[0], u[0], v[0], bottom_dst);                                 \
-  }                                                                            \
-}
-
-// All variants implemented.
-SAMPLE_FUNC(SampleRgbLinePair,      VP8YuvToRgb,  3)
-SAMPLE_FUNC(SampleBgrLinePair,      VP8YuvToBgr,  3)
-SAMPLE_FUNC(SampleRgbaLinePair,     VP8YuvToRgba, 4)
-SAMPLE_FUNC(SampleBgraLinePair,     VP8YuvToBgra, 4)
-SAMPLE_FUNC(SampleArgbLinePair,     VP8YuvToArgb, 4)
-SAMPLE_FUNC(SampleRgba4444LinePair, VP8YuvToRgba4444, 2)
-SAMPLE_FUNC(SampleRgb565LinePair,   VP8YuvToRgb565, 2)
-
-#undef SAMPLE_FUNC
-
-const WebPSampleLinePairFunc WebPSamplers[MODE_LAST] = {
-  SampleRgbLinePair,       // MODE_RGB
-  SampleRgbaLinePair,      // MODE_RGBA
-  SampleBgrLinePair,       // MODE_BGR
-  SampleBgraLinePair,      // MODE_BGRA
-  SampleArgbLinePair,      // MODE_ARGB
-  SampleRgba4444LinePair,  // MODE_RGBA_4444
-  SampleRgb565LinePair,    // MODE_RGB_565
-  SampleRgbaLinePair,      // MODE_rgbA
-  SampleBgraLinePair,      // MODE_bgrA
-  SampleArgbLinePair,      // MODE_Argb
-  SampleRgba4444LinePair   // MODE_rgbA_4444
-};
-
-//------------------------------------------------------------------------------
 
 #if !defined(FANCY_UPSAMPLING)
 #define DUAL_SAMPLE_FUNC(FUNC_NAME, FUNC)                                      \
@@ -235,83 +184,10 @@ const WebPYUV444Converter WebPYUV444Converters[MODE_LAST] = {
 };
 
 //------------------------------------------------------------------------------
-// Premultiplied modes
-
-// non dithered-modes
-
-// (x * a * 32897) >> 23 is bit-wise equivalent to (int)(x * a / 255.)
-// for all 8bit x or a. For bit-wise equivalence to (int)(x * a / 255. + .5),
-// one can use instead: (x * a * 65793 + (1 << 23)) >> 24
-#if 1     // (int)(x * a / 255.)
-#define MULTIPLIER(a)   ((a) * 32897UL)
-#define PREMULTIPLY(x, m) (((x) * (m)) >> 23)
-#else     // (int)(x * a / 255. + .5)
-#define MULTIPLIER(a) ((a) * 65793UL)
-#define PREMULTIPLY(x, m) (((x) * (m) + (1UL << 23)) >> 24)
-#endif
-
-static void ApplyAlphaMultiply(uint8_t* rgba, int alpha_first,
-                               int w, int h, int stride) {
-  while (h-- > 0) {
-    uint8_t* const rgb = rgba + (alpha_first ? 1 : 0);
-    const uint8_t* const alpha = rgba + (alpha_first ? 0 : 3);
-    int i;
-    for (i = 0; i < w; ++i) {
-      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 MULTIPLIER
-#undef PREMULTIPLY
-
-// rgbA4444
-
-#define MULTIPLIER(a)  ((a) * 0x1111)    // 0x1111 ~= (1 << 16) / 15
-
-static WEBP_INLINE uint8_t dither_hi(uint8_t x) {
-  return (x & 0xf0) | (x >> 4);
-}
-
-static WEBP_INLINE uint8_t dither_lo(uint8_t x) {
-  return (x & 0x0f) | (x << 4);
-}
-
-static WEBP_INLINE uint8_t multiply(uint8_t x, uint32_t m) {
-  return (x * m) >> 16;
-}
+// Main calls
 
-static void ApplyAlphaMultiply4444(uint8_t* rgba4444,
-                                   int w, int h, int stride) {
-  while (h-- > 0) {
-    int i;
-    for (i = 0; i < w; ++i) {
-      const uint8_t a = (rgba4444[2 * i + 1] & 0x0f);
-      const uint32_t mult = MULTIPLIER(a);
-      const uint8_t r = multiply(dither_hi(rgba4444[2 * i + 0]), mult);
-      const uint8_t g = multiply(dither_lo(rgba4444[2 * i + 0]), mult);
-      const uint8_t b = multiply(dither_hi(rgba4444[2 * i + 1]), mult);
-      rgba4444[2 * i + 0] = (r & 0xf0) | ((g >> 4) & 0x0f);
-      rgba4444[2 * i + 1] = (b & 0xf0) | a;
-    }
-    rgba4444 += stride;
-  }
-}
-#undef MULTIPLIER
-
-void (*WebPApplyAlphaMultiply)(uint8_t*, int, int, int, int)
-    = ApplyAlphaMultiply;
-void (*WebPApplyAlphaMultiply4444)(uint8_t*, int, int, int)
-    = ApplyAlphaMultiply4444;
-
-//------------------------------------------------------------------------------
-// Main call
+extern void WebPInitUpsamplersSSE2(void);
+extern void WebPInitUpsamplersNEON(void);
 
 void WebPInitUpsamplers(void) {
 #ifdef FANCY_UPSAMPLING
@@ -322,45 +198,25 @@ void WebPInitUpsamplers(void) {
   WebPUpsamplers[MODE_ARGB]      = UpsampleArgbLinePair;
   WebPUpsamplers[MODE_RGBA_4444] = UpsampleRgba4444LinePair;
   WebPUpsamplers[MODE_RGB_565]   = UpsampleRgb565LinePair;
-
-  // If defined, use CPUInfo() to overwrite some pointers with faster versions.
-  if (VP8GetCPUInfo != NULL) {
-#if defined(WEBP_USE_SSE2)
-    if (VP8GetCPUInfo(kSSE2)) {
-      WebPInitUpsamplersSSE2();
-    }
-#endif
-#if defined(WEBP_USE_NEON)
-    if (VP8GetCPUInfo(kNEON)) {
-      WebPInitUpsamplersNEON();
-    }
-#endif
-  }
-#endif  // FANCY_UPSAMPLING
-}
-
-void WebPInitPremultiply(void) {
-  WebPApplyAlphaMultiply = ApplyAlphaMultiply;
-  WebPApplyAlphaMultiply4444 = ApplyAlphaMultiply4444;
-
-#ifdef FANCY_UPSAMPLING
   WebPUpsamplers[MODE_rgbA]      = UpsampleRgbaLinePair;
   WebPUpsamplers[MODE_bgrA]      = UpsampleBgraLinePair;
   WebPUpsamplers[MODE_Argb]      = UpsampleArgbLinePair;
   WebPUpsamplers[MODE_rgbA_4444] = UpsampleRgba4444LinePair;
 
+  // If defined, use CPUInfo() to overwrite some pointers with faster versions.
   if (VP8GetCPUInfo != NULL) {
 #if defined(WEBP_USE_SSE2)
     if (VP8GetCPUInfo(kSSE2)) {
-      WebPInitPremultiplySSE2();
+      WebPInitUpsamplersSSE2();
     }
 #endif
 #if defined(WEBP_USE_NEON)
     if (VP8GetCPUInfo(kNEON)) {
-      WebPInitPremultiplyNEON();
+      WebPInitUpsamplersNEON();
     }
 #endif
   }
 #endif  // FANCY_UPSAMPLING
 }
 
+//------------------------------------------------------------------------------