libwebp-0.6.0-rc1

third_party/libwebp/enc/filter.c

Index: third_party/libwebp/enc/filter.c
diff --git a/third_party/libwebp/enc/filter.c b/third_party/libwebp/enc/filter.c
deleted file mode 100644
index e8ea8b4ff29c2dcd9f2bc17c9a9cdb1e3974c64f..0000000000000000000000000000000000000000
--- a/third_party/libwebp/enc/filter.c
+++ /dev/null
@@ -1,306 +0,0 @@
-// 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.
-// -----------------------------------------------------------------------------
-//
-// Selecting filter level
-//
-// Author: somnath@google.com (Somnath Banerjee)
-
-#include <assert.h>
-#include "./vp8enci.h"
-#include "../dsp/dsp.h"
-
-// This table gives, for a given sharpness, the filtering strength to be
-// used (at least) in order to filter a given edge step delta.
-// This is constructed by brute force inspection: for all delta, we iterate
-// over all possible filtering strength / thresh until needs_filter() returns
-// true.
-#define MAX_DELTA_SIZE 64
-static const uint8_t kLevelsFromDelta[8][MAX_DELTA_SIZE] = {
-  { 0,   1,  2,  3,  4,  5,  6,  7,  8,  9, 10, 11, 12, 13, 14, 15,
-    16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31,
-    32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47,
-    48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63 },
-  { 0,  1,  2,  3,  5,  6,  7,  8,  9, 11, 12, 13, 14, 15, 17, 18,
-    20, 21, 23, 24, 26, 27, 29, 30, 32, 33, 35, 36, 38, 39, 41, 42,
-    44, 45, 47, 48, 50, 51, 53, 54, 56, 57, 59, 60, 62, 63, 63, 63,
-    63, 63, 63, 63, 63, 63, 63, 63, 63, 63, 63, 63, 63, 63, 63, 63 },
-  {  0,  1,  2,  3,  5,  6,  7,  8,  9, 11, 12, 13, 14, 16, 17, 19,
-    20, 22, 23, 25, 26, 28, 29, 31, 32, 34, 35, 37, 38, 40, 41, 43,
-    44, 46, 47, 49, 50, 52, 53, 55, 56, 58, 59, 61, 62, 63, 63, 63,
-    63, 63, 63, 63, 63, 63, 63, 63, 63, 63, 63, 63, 63, 63, 63, 63 },
-  {  0,  1,  2,  3,  5,  6,  7,  8,  9, 11, 12, 13, 15, 16, 18, 19,
-    21, 22, 24, 25, 27, 28, 30, 31, 33, 34, 36, 37, 39, 40, 42, 43,
-    45, 46, 48, 49, 51, 52, 54, 55, 57, 58, 60, 61, 63, 63, 63, 63,
-    63, 63, 63, 63, 63, 63, 63, 63, 63, 63, 63, 63, 63, 63, 63, 63 },
-  {  0,  1,  2,  3,  5,  6,  7,  8,  9, 11, 12, 14, 15, 17, 18, 20,
-    21, 23, 24, 26, 27, 29, 30, 32, 33, 35, 36, 38, 39, 41, 42, 44,
-    45, 47, 48, 50, 51, 53, 54, 56, 57, 59, 60, 62, 63, 63, 63, 63,
-    63, 63, 63, 63, 63, 63, 63, 63, 63, 63, 63, 63, 63, 63, 63, 63 },
-  {  0,  1,  2,  4,  5,  7,  8,  9, 11, 12, 13, 15, 16, 17, 19, 20,
-    22, 23, 25, 26, 28, 29, 31, 32, 34, 35, 37, 38, 40, 41, 43, 44,
-    46, 47, 49, 50, 52, 53, 55, 56, 58, 59, 61, 62, 63, 63, 63, 63,
-    63, 63, 63, 63, 63, 63, 63, 63, 63, 63, 63, 63, 63, 63, 63, 63 },
-  {  0,  1,  2,  4,  5,  7,  8,  9, 11, 12, 13, 15, 16, 18, 19, 21,
-    22, 24, 25, 27, 28, 30, 31, 33, 34, 36, 37, 39, 40, 42, 43, 45,
-    46, 48, 49, 51, 52, 54, 55, 57, 58, 60, 61, 63, 63, 63, 63, 63,
-    63, 63, 63, 63, 63, 63, 63, 63, 63, 63, 63, 63, 63, 63, 63, 63 },
-  {  0,  1,  2,  4,  5,  7,  8,  9, 11, 12, 14, 15, 17, 18, 20, 21,
-    23, 24, 26, 27, 29, 30, 32, 33, 35, 36, 38, 39, 41, 42, 44, 45,
-    47, 48, 50, 51, 53, 54, 56, 57, 59, 60, 62, 63, 63, 63, 63, 63,
-    63, 63, 63, 63, 63, 63, 63, 63, 63, 63, 63, 63, 63, 63, 63, 63 }
-};
-
-int VP8FilterStrengthFromDelta(int sharpness, int delta) {
-  const int pos = (delta < MAX_DELTA_SIZE) ? delta : MAX_DELTA_SIZE - 1;
-  assert(sharpness >= 0 && sharpness <= 7);
-  return kLevelsFromDelta[sharpness][pos];
-}
-
-//------------------------------------------------------------------------------
-// Paragraph 15.4: compute the inner-edge filtering strength
-
-static int GetILevel(int sharpness, int level) {
-  if (sharpness > 0) {
-    if (sharpness > 4) {
-      level >>= 2;
-    } else {
-      level >>= 1;
-    }
-    if (level > 9 - sharpness) {
-      level = 9 - sharpness;
-    }
-  }
-  if (level < 1) level = 1;
-  return level;
-}
-
-static void DoFilter(const VP8EncIterator* const it, int level) {
-  const VP8Encoder* const enc = it->enc_;
-  const int ilevel = GetILevel(enc->config_->filter_sharpness, level);
-  const int limit = 2 * level + ilevel;
-
-  uint8_t* const y_dst = it->yuv_out2_ + Y_OFF_ENC;
-  uint8_t* const u_dst = it->yuv_out2_ + U_OFF_ENC;
-  uint8_t* const v_dst = it->yuv_out2_ + V_OFF_ENC;
-
-  // copy current block to yuv_out2_
-  memcpy(y_dst, it->yuv_out_, YUV_SIZE_ENC * sizeof(uint8_t));
-
-  if (enc->filter_hdr_.simple_ == 1) {   // simple
-    VP8SimpleHFilter16i(y_dst, BPS, limit);
-    VP8SimpleVFilter16i(y_dst, BPS, limit);
-  } else {    // complex
-    const int hev_thresh = (level >= 40) ? 2 : (level >= 15) ? 1 : 0;
-    VP8HFilter16i(y_dst, BPS, limit, ilevel, hev_thresh);
-    VP8HFilter8i(u_dst, v_dst, BPS, limit, ilevel, hev_thresh);
-    VP8VFilter16i(y_dst, BPS, limit, ilevel, hev_thresh);
-    VP8VFilter8i(u_dst, v_dst, BPS, limit, ilevel, hev_thresh);
-  }
-}
-
-//------------------------------------------------------------------------------
-// SSIM metric
-
-static const double kMinValue = 1.e-10;  // minimal threshold
-
-void VP8SSIMAddStats(const VP8DistoStats* const src, VP8DistoStats* const dst) {
-  dst->w   += src->w;
-  dst->xm  += src->xm;
-  dst->ym  += src->ym;
-  dst->xxm += src->xxm;
-  dst->xym += src->xym;
-  dst->yym += src->yym;
-}
-
-double VP8SSIMGet(const VP8DistoStats* const stats) {
-  const double xmxm = stats->xm * stats->xm;
-  const double ymym = stats->ym * stats->ym;
-  const double xmym = stats->xm * stats->ym;
-  const double w2 = stats->w * stats->w;
-  double sxx = stats->xxm * stats->w - xmxm;
-  double syy = stats->yym * stats->w - ymym;
-  double sxy = stats->xym * stats->w - xmym;
-  double C1, C2;
-  double fnum;
-  double fden;
-  // small errors are possible, due to rounding. Clamp to zero.
-  if (sxx < 0.) sxx = 0.;
-  if (syy < 0.) syy = 0.;
-  C1 = 6.5025 * w2;
-  C2 = 58.5225 * w2;
-  fnum = (2 * xmym + C1) * (2 * sxy + C2);
-  fden = (xmxm + ymym + C1) * (sxx + syy + C2);
-  return (fden != 0.) ? fnum / fden : kMinValue;
-}
-
-double VP8SSIMGetSquaredError(const VP8DistoStats* const s) {
-  if (s->w > 0.) {
-    const double iw2 = 1. / (s->w * s->w);
-    const double sxx = s->xxm * s->w - s->xm * s->xm;
-    const double syy = s->yym * s->w - s->ym * s->ym;
-    const double sxy = s->xym * s->w - s->xm * s->ym;
-    const double SSE = iw2 * (sxx + syy - 2. * sxy);
-    if (SSE > kMinValue) return SSE;
-  }
-  return kMinValue;
-}
-
-#define LIMIT(A, M)  ((A) > (M) ? (M) : (A))
-static void VP8SSIMAccumulateRow(const uint8_t* src1, int stride1,
-                                 const uint8_t* src2, int stride2,
-                                 int y, int W, int H,
-                                 VP8DistoStats* const stats) {
-  int x = 0;
-  const int w0 = LIMIT(VP8_SSIM_KERNEL, W);
-  for (x = 0; x < w0; ++x) {
-    VP8SSIMAccumulateClipped(src1, stride1, src2, stride2, x, y, W, H, stats);
-  }
-  for (; x <= W - 8 + VP8_SSIM_KERNEL; ++x) {
-    VP8SSIMAccumulate(
-        src1 + (y - VP8_SSIM_KERNEL) * stride1 + (x - VP8_SSIM_KERNEL), stride1,
-        src2 + (y - VP8_SSIM_KERNEL) * stride2 + (x - VP8_SSIM_KERNEL), stride2,
-        stats);
-  }
-  for (; x < W; ++x) {
-    VP8SSIMAccumulateClipped(src1, stride1, src2, stride2, x, y, W, H, stats);
-  }
-}
-
-void VP8SSIMAccumulatePlane(const uint8_t* src1, int stride1,
-                            const uint8_t* src2, int stride2,
-                            int W, int H, VP8DistoStats* const stats) {
-  int x, y;
-  const int h0 = LIMIT(VP8_SSIM_KERNEL, H);
-  const int h1 = LIMIT(VP8_SSIM_KERNEL, H - VP8_SSIM_KERNEL);
-  for (y = 0; y < h0; ++y) {
-    for (x = 0; x < W; ++x) {
-      VP8SSIMAccumulateClipped(src1, stride1, src2, stride2, x, y, W, H, stats);
-    }
-  }
-  for (; y < h1; ++y) {
-    VP8SSIMAccumulateRow(src1, stride1, src2, stride2, y, W, H, stats);
-  }
-  for (; y < H; ++y) {
-    for (x = 0; x < W; ++x) {
-      VP8SSIMAccumulateClipped(src1, stride1, src2, stride2, x, y, W, H, stats);
-    }
-  }
-}
-#undef LIMIT
-
-static double GetMBSSIM(const uint8_t* yuv1, const uint8_t* yuv2) {
-  int x, y;
-  VP8DistoStats s = { .0, .0, .0, .0, .0, .0 };
-
-  // compute SSIM in a 10 x 10 window
-  for (y = VP8_SSIM_KERNEL; y < 16 - VP8_SSIM_KERNEL; y++) {
-    for (x = VP8_SSIM_KERNEL; x < 16 - VP8_SSIM_KERNEL; x++) {
-      VP8SSIMAccumulateClipped(yuv1 + Y_OFF_ENC, BPS, yuv2 + Y_OFF_ENC, BPS,
-                               x, y, 16, 16, &s);
-    }
-  }
-  for (x = 1; x < 7; x++) {
-    for (y = 1; y < 7; y++) {
-      VP8SSIMAccumulateClipped(yuv1 + U_OFF_ENC, BPS, yuv2 + U_OFF_ENC, BPS,
-                               x, y, 8, 8, &s);
-      VP8SSIMAccumulateClipped(yuv1 + V_OFF_ENC, BPS, yuv2 + V_OFF_ENC, BPS,
-                               x, y, 8, 8, &s);
-    }
-  }
-  return VP8SSIMGet(&s);
-}
-
-//------------------------------------------------------------------------------
-// Exposed APIs: Encoder should call the following 3 functions to adjust
-// loop filter strength
-
-void VP8InitFilter(VP8EncIterator* const it) {
-  if (it->lf_stats_ != NULL) {
-    int s, i;
-    for (s = 0; s < NUM_MB_SEGMENTS; s++) {
-      for (i = 0; i < MAX_LF_LEVELS; i++) {
-        (*it->lf_stats_)[s][i] = 0;
-      }
-    }
-    VP8SSIMDspInit();
-  }
-}
-
-void VP8StoreFilterStats(VP8EncIterator* const it) {
-  int d;
-  VP8Encoder* const enc = it->enc_;
-  const int s = it->mb_->segment_;
-  const int level0 = enc->dqm_[s].fstrength_;
-
-  // explore +/-quant range of values around level0
-  const int delta_min = -enc->dqm_[s].quant_;
-  const int delta_max = enc->dqm_[s].quant_;
-  const int step_size = (delta_max - delta_min >= 4) ? 4 : 1;
-
-  if (it->lf_stats_ == NULL) return;
-
-  // NOTE: Currently we are applying filter only across the sublock edges
-  // There are two reasons for that.
-  // 1. Applying filter on macro block edges will change the pixels in
-  // the left and top macro blocks. That will be hard to restore
-  // 2. Macro Blocks on the bottom and right are not yet compressed. So we
-  // cannot apply filter on the right and bottom macro block edges.
-  if (it->mb_->type_ == 1 && it->mb_->skip_) return;
-
-  // Always try filter level  zero
-  (*it->lf_stats_)[s][0] += GetMBSSIM(it->yuv_in_, it->yuv_out_);
-
-  for (d = delta_min; d <= delta_max; d += step_size) {
-    const int level = level0 + d;
-    if (level <= 0 || level >= MAX_LF_LEVELS) {
-      continue;
-    }
-    DoFilter(it, level);
-    (*it->lf_stats_)[s][level] += GetMBSSIM(it->yuv_in_, it->yuv_out2_);
-  }
-}
-
-void VP8AdjustFilterStrength(VP8EncIterator* const it) {
-  VP8Encoder* const enc = it->enc_;
-  if (it->lf_stats_ != NULL) {
-    int s;
-    for (s = 0; s < NUM_MB_SEGMENTS; s++) {
-      int i, best_level = 0;
-      // Improvement over filter level 0 should be at least 1e-5 (relatively)
-      double best_v = 1.00001 * (*it->lf_stats_)[s][0];
-      for (i = 1; i < MAX_LF_LEVELS; i++) {
-        const double v = (*it->lf_stats_)[s][i];
-        if (v > best_v) {
-          best_v = v;
-          best_level = i;
-        }
-      }
-      enc->dqm_[s].fstrength_ = best_level;
-    }
-  } else if (enc->config_->filter_strength > 0) {
-    int max_level = 0;
-    int s;
-    for (s = 0; s < NUM_MB_SEGMENTS; s++) {
-      VP8SegmentInfo* const dqm = &enc->dqm_[s];
-      // this '>> 3' accounts for some inverse WHT scaling
-      const int delta = (dqm->max_edge_ * dqm->y2_.q_[1]) >> 3;
-      const int level =
-          VP8FilterStrengthFromDelta(enc->filter_hdr_.sharpness_, delta);
-      if (level > dqm->fstrength_) {
-        dqm->fstrength_ = level;
-      }
-      if (max_level < dqm->fstrength_) {
-        max_level = dqm->fstrength_;
-      }
-    }
-    enc->filter_hdr_.level_ = max_level;
-  }
-}
-
-// -----------------------------------------------------------------------------