Adds a blockiness metric to internal stats.

Change-Id: Iedceeb020492050063acf3fd2326f96c29db9ae5

test/blockiness_test.cc

+/*
+ *  Copyright (c) 2012 The WebM project authors. All Rights Reserved.
+ *
+ *  Use of this source code is governed by a BSD-style license
+ *  that can be found in the LICENSE 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.
+ */
+
+
+#include <string.h>
+#include <limits.h>
+#include <stdio.h>
+
+#include "./vpx_config.h"
+#if CONFIG_VP9_ENCODER
+#include "./vp9_rtcd.h"
+#endif
+
+#include "test/acm_random.h"
+#include "test/clear_system_state.h"
+#include "test/register_state_check.h"
+#include "test/util.h"
+#include "third_party/googletest/src/include/gtest/gtest.h"
+
+#include "vpx_mem/vpx_mem.h"
+
+
+extern "C"
+double vp9_get_blockiness(const unsigned char *img1, int img1_pitch,
+                          const unsigned char *img2, int img2_pitch,
+                          int width, int height);
+
+using libvpx_test::ACMRandom;
+
+namespace {
+class BlockinessTestBase : public ::testing::Test {
+ public:
+  BlockinessTestBase(int width, int height) : width_(width), height_(height) {}
+
+  static void SetUpTestCase() {
+    source_data_ = reinterpret_cast<uint8_t*>(
+        vpx_memalign(kDataAlignment, kDataBufferSize));
+    reference_data_ = reinterpret_cast<uint8_t*>(
+        vpx_memalign(kDataAlignment, kDataBufferSize));
+  }
+
+  static void TearDownTestCase() {
+    vpx_free(source_data_);
+    source_data_ = NULL;
+    vpx_free(reference_data_);
+    reference_data_ = NULL;
+  }
+
+  virtual void TearDown() {
+    libvpx_test::ClearSystemState();
+  }
+
+ protected:
+  // Handle frames up to 640x480
+  static const int kDataAlignment = 16;
+  static const int kDataBufferSize = 640*480;
+
+  virtual void SetUp() {
+    source_stride_ = (width_ + 31) & ~31;
+    reference_stride_ = width_ * 2;
+    rnd_.Reset(ACMRandom::DeterministicSeed());
+  }
+
+  void FillConstant(uint8_t *data, int stride, uint8_t fill_constant,
+                    int width, int height) {
+    for (int h = 0; h < height; ++h) {
+      for (int w = 0; w < width; ++w) {
+        data[h * stride + w] = fill_constant;
+      }
+    }
+  }
+
+  void FillConstant(uint8_t *data, int stride, uint8_t fill_constant) {
+    FillConstant(data, stride, fill_constant, width_, height_);
+  }
+
+  void FillRandom(uint8_t *data, int stride, int width, int height) {
+    for (int h = 0; h < height; ++h) {
+      for (int w = 0; w < width; ++w) {
+        data[h * stride + w] = rnd_.Rand8();
+      }
+    }
+  }
+
+  void FillRandom(uint8_t *data, int stride) {
+    FillRandom(data, stride, width_, height_);
+  }
+
+  void FillRandomBlocky(uint8_t *data, int stride) {
+    for (int h = 0; h < height_; h += 4) {
+      for (int w = 0; w < width_; w += 4) {
+        FillRandom(data + h * stride + w, stride, 4, 4);
+      }
+    }
+  }
+
+  void FillCheckerboard(uint8_t *data, int stride) {
+    for (int h = 0; h < height_; h += 4) {
+      for (int w = 0; w < width_; w += 4) {
+        if (((h/4) ^ (w/4)) & 1)
+          FillConstant(data + h * stride + w, stride, 255, 4, 4);
+        else
+          FillConstant(data + h * stride + w, stride, 0, 4, 4);
+      }
+    }
+  }
+
+  void Blur(uint8_t *data, int stride, int taps) {
+    int sum = 0;
+    int half_taps = taps / 2;
+    for (int h = 0; h < height_; ++h) {
+      for (int w = 0; w < taps; ++w) {
+        sum += data[w + h * stride];
+      }
+      for (int w = taps; w < width_; ++w) {
+        sum += data[w + h * stride] - data[w - taps + h * stride];
+        data[w - half_taps + h * stride] = (sum + half_taps) / taps;
+      }
+    }
+    for (int w = 0; w < width_; ++w) {
+      for (int h = 0; h < taps; ++h) {
+        sum += data[h + w * stride];
+      }
+      for (int h = taps; h < height_; ++h) {
+        sum += data[w + h * stride] - data[(h - taps) * stride + w];
+        data[(h - half_taps) * stride + w] = (sum + half_taps) / taps;
+      }
+    }
+  }
+  int width_, height_;
+  static uint8_t* source_data_;
+  int source_stride_;
+  static uint8_t* reference_data_;
+  int reference_stride_;
+
+  ACMRandom rnd_;
+};
+
+#if CONFIG_VP9_ENCODER
+typedef std::tr1::tuple<int, int> BlockinessParam;
+class BlockinessVP9Test
+    : public BlockinessTestBase,
+      public ::testing::WithParamInterface<BlockinessParam> {
+ public:
+  BlockinessVP9Test() : BlockinessTestBase(GET_PARAM(0), GET_PARAM(1)) {}
+
+ protected:
+  int CheckBlockiness() {
+    return vp9_get_blockiness(source_data_, source_stride_,
+                              reference_data_, reference_stride_,
+                              width_, height_);
+  }
+};
+#endif  // CONFIG_VP9_ENCODER
+
+uint8_t* BlockinessTestBase::source_data_ = NULL;
+uint8_t* BlockinessTestBase::reference_data_ = NULL;
+
+#if CONFIG_VP9_ENCODER
+TEST_P(BlockinessVP9Test, SourceBlockierThanReference) {
+  // Source is blockier than reference.
+  FillRandomBlocky(source_data_, source_stride_);
+  FillConstant(reference_data_, reference_stride_, 128);
+  int super_blocky = CheckBlockiness();
+
+  EXPECT_EQ(0, super_blocky) << "Blocky source should produce 0 blockiness.";
+}
+
+TEST_P(BlockinessVP9Test, ReferenceBlockierThanSource) {
+  // Source is blockier than reference.
+  FillConstant(source_data_, source_stride_, 128);
+  FillRandomBlocky(reference_data_, reference_stride_);
+  int super_blocky = CheckBlockiness();
+
+  EXPECT_GT(super_blocky, 0.0)
+      << "Blocky reference should score high for blockiness.";
+}
+
+TEST_P(BlockinessVP9Test, BlurringDecreasesBlockiness) {
+  // Source is blockier than reference.
+  FillConstant(source_data_, source_stride_, 128);
+  FillRandomBlocky(reference_data_, reference_stride_);
+  int super_blocky = CheckBlockiness();
+
+  Blur(reference_data_, reference_stride_, 4);
+  int less_blocky = CheckBlockiness();
+
+  EXPECT_GT(super_blocky, less_blocky)
+      << "A straight blur should decrease blockiness.";
+}
+
+TEST_P(BlockinessVP9Test, WorstCaseBlockiness) {
+  // Source is blockier than reference.
+  FillConstant(source_data_, source_stride_, 128);
+  FillCheckerboard(reference_data_, reference_stride_);
+
+  int super_blocky = CheckBlockiness();
+
+  Blur(reference_data_, reference_stride_, 4);
+  int less_blocky = CheckBlockiness();
+
+  EXPECT_GT(super_blocky, less_blocky)
+      << "A straight blur should decrease blockiness.";
+}
+#endif  // CONFIG_VP9_ENCODER
+
+
+using std::tr1::make_tuple;
+
+//------------------------------------------------------------------------------
+// C functions
+
+#if CONFIG_VP9_ENCODER
+const BlockinessParam c_vp9_tests[] = {
+  make_tuple(320, 240),
+  make_tuple(318, 242),
+  make_tuple(318, 238),
+};
+INSTANTIATE_TEST_CASE_P(C, BlockinessVP9Test, ::testing::ValuesIn(c_vp9_tests));
+#endif
+
+}  // namespace

test/test.mk

@@ -150,6 +150,7 @@ LIBVPX_TEST_SRCS-$(CONFIG_VP9)         += vp9_intrapred_test.cc
 
 ifeq ($(CONFIG_VP9_ENCODER),yes)
 LIBVPX_TEST_SRCS-$(CONFIG_SPATIAL_SVC) += svc_test.cc
+LIBVPX_TEST_SRCS-$(CONFIG_INTERNAL_STATS) += blockiness_test.cc
 endif
 
 ifeq ($(CONFIG_VP9_ENCODER)$(CONFIG_VP9_TEMPORAL_DENOISING),yesyes)

vp9/encoder/vp9_blockiness.c

+/*
+ *  Copyright (c) 2014 The WebM project authors. All Rights Reserved.
+ *
+ *  Use of this source code is governed by a BSD-style license
+ *  that can be found in the LICENSE 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.
+ */
+
+#include "./vpx_config.h"
+#include "./vp9_rtcd.h"
+#include "vp9/common/vp9_common.h"
+#include "vp9/common/vp9_convolve.h"
+#include "vp9/common/vp9_filter.h"
+#include "vpx/vpx_integer.h"
+#include "vpx_ports/mem.h"
+
+static int horizontal_filter(const uint8_t *s) {
+  return (s[1] - s[-2]) * 2 + (s[-1] - s[0]) * 6;
+}
+
+static int vertical_filter(const uint8_t *s, int p) {
+  return (s[p] - s[-2 * p]) * 2 + (s[-p] - s[0]) * 6;
+}
+
+static int variance(int sum, int sum_squared, int size) {
+  return sum_squared / size - (sum / size) * (sum / size);
+}
+// Calculate a blockiness level for a vertical block edge.
+// This function returns a new blockiness metric that's defined as
+
+//              p0 p1 p2 p3
+//              q0 q1 q2 q3
+// block edge ->
+//              r0 r1 r2 r3
+//              s0 s1 s2 s3
+
+// blockiness =  p0*-2+q0*6+r0*-6+s0*2 +
+//               p1*-2+q1*6+r1*-6+s1*2 +
+//               p2*-2+q2*6+r2*-6+s2*2 +
+//               p3*-2+q3*6+r3*-6+s3*2 ;
+
+// reconstructed_blockiness = abs(blockiness from reconstructed buffer -
+//                                blockiness from source buffer,0)
+//
+// I make the assumption that flat blocks are much more visible than high
+// contrast blocks. As such, I scale the result of the blockiness calc
+// by dividing the blockiness by the variance of the pixels on either side
+// of the edge as follows:
+// var_0 = (q0^2+q1^2+q2^2+q3^2) - ((q0 + q1 + q2 + q3) / 4 )^2
+// var_1 = (r0^2+r1^2+r2^2+r3^2) - ((r0 + r1 + r2 + r3) / 4 )^2
+// The returned blockiness is the scaled value
+// Reconstructed blockiness / ( 1 + var_0 + var_1 ) ;
+int blockiness_vertical(const uint8_t *s, int sp, const uint8_t *r, int rp,
+                        int size) {
+  int s_blockiness = 0;
+  int r_blockiness = 0;
+  int sum_0 = 0;
+  int sum_sq_0 = 0;
+  int sum_1 = 0;
+  int sum_sq_1 = 0;
+  int i;
+  int var_0;
+  int var_1;
+  for (i = 0; i < size; ++i, s += sp, r += rp) {
+    s_blockiness += horizontal_filter(s);
+    r_blockiness += horizontal_filter(r);
+    sum_0 += s[0];
+    sum_sq_0 += s[0]*s[0];
+    sum_1 += s[-1];
+    sum_sq_1 += s[-1]*s[-1];
+  }
+  var_0 = variance(sum_0, sum_sq_0, size);
+  var_1 = variance(sum_1, sum_sq_1, size);
+  r_blockiness = abs(r_blockiness);
+  s_blockiness = abs(s_blockiness);
+
+  if (r_blockiness > s_blockiness)
+    return (r_blockiness - s_blockiness) / (1 + var_0 + var_1);
+  else
+    return 0;
+}
+
+// Calculate a blockiness level for a horizontal block edge
+// same as above.
+int blockiness_horizontal(const uint8_t *s, int sp, const uint8_t *r, int rp,
+                          int size) {
+  int s_blockiness = 0;
+  int r_blockiness = 0;
+  int sum_0 = 0;
+  int sum_sq_0 = 0;
+  int sum_1 = 0;
+  int sum_sq_1 = 0;
+  int i;
+  int var_0;
+  int var_1;
+  for (i = 0; i < size; ++i, ++s, ++r) {
+    s_blockiness += vertical_filter(s, sp);
+    r_blockiness += vertical_filter(r, rp);
+    sum_0 += s[0];
+    sum_sq_0 += s[0] * s[0];
+    sum_1 += s[-sp];
+    sum_sq_1 += s[-sp] * s[-sp];
+  }
+  var_0 = variance(sum_0, sum_sq_0, size);
+  var_1 = variance(sum_1, sum_sq_1, size);
+  r_blockiness = abs(r_blockiness);
+  s_blockiness = abs(s_blockiness);
+
+  if (r_blockiness > s_blockiness)
+    return (r_blockiness - s_blockiness) / (1 + var_0 + var_1);
+  else
+    return 0;
+}
+
+// This function returns the blockiness for the entire frame currently by
+// looking at all borders in steps of 4.
+double vp9_get_blockiness(const unsigned char *img1, int img1_pitch,
+                          const unsigned char *img2, int img2_pitch,
+                          int width, int height ) {
+  double blockiness = 0;
+  int i, j;
+  vp9_clear_system_state();
+  for (i = 0; i < height; i += 4, img1 += img1_pitch * 4,
+       img2 += img2_pitch * 4) {
+    for (j = 0; j < width; j += 4) {
+      if (i > 0 && i < height && j > 0 && j < width) {
+        blockiness += blockiness_vertical(img1 + j, img1_pitch,
+                                          img2 + j, img2_pitch, 4);
+        blockiness += blockiness_horizontal(img1 + j, img1_pitch,
+                                            img2 + j, img2_pitch, 4);
+      }
+    }
+  }
+  blockiness /= width * height / 16;
+  return blockiness;
+}

vp9/encoder/vp9_encoder.c

@@ -1583,6 +1583,8 @@ VP9_COMP *vp9_create_compressor(VP9EncoderConfig *oxcf,
   cpi->b_calculate_psnr = CONFIG_INTERNAL_STATS;
 #if CONFIG_INTERNAL_STATS
   cpi->b_calculate_ssimg = 0;
+  cpi->b_calculate_blockiness = 1;
+
 
   cpi->count = 0;
   cpi->bytes = 0;
@@ -1624,6 +1626,15 @@ VP9_COMP *vp9_create_compressor(VP9EncoderConfig *oxcf,
   cpi->total_psnrhvs_u = 0;
   cpi->total_psnrhvs_v = 0;
   cpi->total_psnrhvs_all = 0;
+
+  if (cpi->b_calculate_blockiness) {
+    cpi->total_blockiness = 0;
+  }
+
+  if (cpi->b_calculate_blockiness) {
+    cpi->total_blockiness = 0;
+  }
+
 #endif
 
   cpi->first_time_stamp_ever = INT64_MAX;
@@ -1831,7 +1842,6 @@ void vp9_remove_compressor(VP9_COMP *cpi) {
 
   if (cpi && (cm->current_video_frame > 0)) {
 #if CONFIG_INTERNAL_STATS
-
     vp9_clear_system_state();
 
     // printf("\n8x8-4x4:%d-%d\n", cpi->t8x8_count, cpi->t4x4_count);
@@ -1854,19 +1864,28 @@ void vp9_remove_compressor(VP9_COMP *cpi) {
                             (double)cpi->totalp_sq_error);
         const double total_ssim = 100 * pow(cpi->summed_quality /
                                                 cpi->summed_weights, 8.0);
-        const double totalp_ssim = 100 * pow(cpi->summedp_quality /
-                                                cpi->summedp_weights, 8.0);
-
-
-        fprintf(f, "Bitrate\tAVGPsnr\tGLBPsnr\tAVPsnrP\tGLPsnrP\t"
+        if (cpi->b_calculate_blockiness) {
+          fprintf(f, "Bitrate\tAVGPsnr\tGLBPsnr\tAVPsnrP\tGLPsnrP\t"
                 "VPXSSIM\tVPSSIMP\tFASTSSIM\tPSNRHVS\tTime(ms)\n");
-        fprintf(f, "%7.2f\t%7.3f\t%7.3f\t%7.3f\t%7.3f\t%7.3f\t"
-                "%7.3f\t%7.3f\t%7.3f\t%8.0f\n",
-                dr, cpi->total / cpi->count, total_psnr,
-                cpi->totalp / cpi->count, totalp_psnr, total_ssim, totalp_ssim,
+          fprintf(f, "%7.2f\t%7.3f\t%7.3f\t%7.3f\t%7.3f\t%7.3f\t"
+                "%7.3f\t%7.3f\t%8.0f\n",
+                  dr, cpi->total / cpi->count, total_psnr,
+                  cpi->totalp / cpi->count, totalp_psnr, total_ssim,
                 cpi->total_fastssim_all / cpi->count,
                 cpi->total_psnrhvs_all / cpi->count,
                 total_encode_time);
+        } else {
+          fprintf(f, "Bitrate\tAVGPsnr\tGLBPsnr\tAVPsnrP\tGLPsnrP\t"
+                "VPXSSIM\tVPSSIMP\tBlockiness\tFASTSSIM\tPSNRHVS\tTime(ms)\n");
+          fprintf(f, "%7.2f\t%7.3f\t%7.3f\t%7.3f\t%7.3f\t%7.3f\t"
+                  "%7.3f\t%7.3f\t%7.3f\t%8.0f\n",
+                  dr, cpi->total / cpi->count, total_psnr,
+                  cpi->totalp / cpi->count, totalp_psnr, total_ssim,
+                  cpi->total_blockiness / cpi->count,
+                  cpi->total_fastssim_all / cpi->count,
+                  cpi->total_psnrhvs_all / cpi->count,
+                  total_encode_time);
+        }
       }
 
 
@@ -3786,6 +3805,12 @@ static void check_src_altref(VP9_COMP *cpi,
   }
 }
 
+#if CONFIG_INTERNAL_STATS
+extern double vp9_get_blockiness(const unsigned char *img1, int img1_pitch,
+                                 const unsigned char *img2, int img2_pitch,
+                                 int width, int height);
+#endif
+
 int vp9_get_compressed_data(VP9_COMP *cpi, unsigned int *frame_flags,
                             size_t *size, uint8_t *dest,
                             int64_t *time_stamp, int64_t *time_end, int flush) {
@@ -4135,7 +4160,12 @@ int vp9_get_compressed_data(VP9_COMP *cpi, unsigned int *frame_flags,
 #endif
         }
       }
-
+      if (cpi->b_calculate_blockiness)
+        cpi->total_blockiness +=
+            vp9_get_blockiness(cpi->Source->y_buffer, cpi->Source->y_stride,
+                               cm->frame_to_show->y_buffer,
+                               cm->frame_to_show->y_stride,
+                               cpi->Source->y_width, cpi->Source->y_height);
 
       if (cpi->b_calculate_ssimg) {
         double y, u, v, frame_all;

vp9/encoder/vp9_encoder.h

@@ -402,6 +402,8 @@ typedef struct VP9_COMP {
   uint64_t totalp_sq_error;
   uint64_t totalp_samples;
 
+  double total_blockiness;
+
   int    bytes;
   double summed_quality;
   double summed_weights;
@@ -426,6 +428,7 @@ typedef struct VP9_COMP {
   double total_psnrhvs_all;
 
   int b_calculate_ssimg;
+  int b_calculate_blockiness;
 #endif
   int b_calculate_psnr;
 

vp9/vp9cx.mk

@@ -81,6 +81,8 @@ VP9_CX_SRCS-yes += encoder/vp9_resize.c
 VP9_CX_SRCS-yes += encoder/vp9_resize.h
 VP9_CX_SRCS-$(CONFIG_INTERNAL_STATS) += encoder/vp9_ssim.c
 VP9_CX_SRCS-$(CONFIG_INTERNAL_STATS) += encoder/vp9_ssim.h
+VP9_CX_SRCS-$(CONFIG_INTERNAL_STATS) += encoder/vp9_blockiness.c
+
 VP9_CX_SRCS-yes += encoder/vp9_tokenize.c
 VP9_CX_SRCS-yes += encoder/vp9_treewriter.c
 VP9_CX_SRCS-yes += encoder/vp9_variance.c