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vp9: Compute skin only for blocks eligible for noise estimation.

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Change-Id: Iddcb83a5968db57cfd312c5bc44b2a226a2a3264
This commit is contained in:
Jerome Jiang
2017-07-14 13:45:33 -07:00
parent 666e394d41
commit 682135fa60
1 changed files with 32 additions and 26 deletions
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58
vp9/encoder/vp9_noise_estimate.c
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@@ -172,7 +172,6 @@ void vp9_update_noise_estimate(VP9_COMP *const cpi) {
int mi_row, mi_col;
int num_low_motion = 0;
int frame_low_motion = 1;
if (cpi->use_skin_detection) vp9_compute_skin_map(cpi, BLOCK_16X16);
for (mi_row = 0; mi_row < cm->mi_rows; mi_row++) {
for (mi_col = 0; mi_col < cm->mi_cols; mi_col++) {
int bl_index = mi_row * cm->mi_cols + mi_col;
@@ -191,35 +190,42 @@ void vp9_update_noise_estimate(VP9_COMP *const cpi) {
int bl_index1 = bl_index + 1;
int bl_index2 = bl_index + cm->mi_cols;
int bl_index3 = bl_index2 + 1;
int is_skin = 0;
if (cpi->use_skin_detection) is_skin = cpi->skin_map[bl_index];
int consec_zeromv =
VPXMIN(cpi->consec_zero_mv[bl_index],
VPXMIN(cpi->consec_zero_mv[bl_index1],
VPXMIN(cpi->consec_zero_mv[bl_index2],
cpi->consec_zero_mv[bl_index3])));
// Only consider blocks that are likely steady background. i.e, have
// been encoded as zero/low motion x (= thresh_consec_zeromv) frames
// in a row. consec_zero_mv[] defined for 8x8 blocks, so consider all
// 4 sub-blocks for 16x16 block. Also, avoid skin blocks.
if (frame_low_motion &&
cpi->consec_zero_mv[bl_index] > thresh_consec_zeromv &&
cpi->consec_zero_mv[bl_index1] > thresh_consec_zeromv &&
cpi->consec_zero_mv[bl_index2] > thresh_consec_zeromv &&
cpi->consec_zero_mv[bl_index3] > thresh_consec_zeromv &&
!is_skin) {
// Compute variance.
unsigned int sse;
unsigned int variance = cpi->fn_ptr[bsize].vf(
src_y, src_ystride, last_src_y, last_src_ystride, &sse);
// Only consider this block as valid for noise measurement if the
// average term (sse - variance = N * avg^{2}, N = 16X16) of the
// temporal residual is small (avoid effects from lighting change).
if ((sse - variance) < thresh_sum_diff) {
unsigned int sse2;
const unsigned int spatial_variance = cpi->fn_ptr[bsize].vf(
src_y, src_ystride, const_source, 0, &sse2);
// Avoid blocks with high brightness and high spatial variance.
if ((sse2 - spatial_variance) < thresh_sum_spatial &&
spatial_variance < thresh_spatial_var) {
avg_est += low_res ? variance >> 4
: variance / ((spatial_variance >> 9) + 1);
num_samples++;
if (frame_low_motion && consec_zeromv > thresh_consec_zeromv) {
int is_skin = 0;
if (cpi->use_skin_detection) {
is_skin =
vp9_compute_skin_block(src_y, src_u, src_v, src_ystride,
src_uvstride, bsize, consec_zeromv, 0);
}
if (!is_skin) {
unsigned int sse;
// Compute variance.
unsigned int variance = cpi->fn_ptr[bsize].vf(
src_y, src_ystride, last_src_y, last_src_ystride, &sse);
// Only consider this block as valid for noise measurement if the
// average term (sse - variance = N * avg^{2}, N = 16X16) of the
// temporal residual is small (avoid effects from lighting
// change).
if ((sse - variance) < thresh_sum_diff) {
unsigned int sse2;
const unsigned int spatial_variance = cpi->fn_ptr[bsize].vf(
src_y, src_ystride, const_source, 0, &sse2);
// Avoid blocks with high brightness and high spatial variance.
if ((sse2 - spatial_variance) < thresh_sum_spatial &&
spatial_variance < thresh_spatial_var) {
avg_est += low_res ? variance >> 4
: variance / ((spatial_variance >> 9) + 1);
num_samples++;
}
}
}
}