diff options
Diffstat (limited to 'chromium/third_party/libvpx/source/libvpx/vp9/encoder/vp9_blockiness.c')
-rw-r--r-- | chromium/third_party/libvpx/source/libvpx/vp9/encoder/vp9_blockiness.c | 138 |
1 files changed, 0 insertions, 138 deletions
diff --git a/chromium/third_party/libvpx/source/libvpx/vp9/encoder/vp9_blockiness.c b/chromium/third_party/libvpx/source/libvpx/vp9/encoder/vp9_blockiness.c deleted file mode 100644 index b8629bd3bb5..00000000000 --- a/chromium/third_party/libvpx/source/libvpx/vp9/encoder/vp9_blockiness.c +++ /dev/null @@ -1,138 +0,0 @@ -/* - * 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; -} |