ref: ff36b9c78b8a069978c7ba57c31a8b63fbf8b599
parent: c72dc3963e5a2d96709669d0471158f8b1a60d9e
author: Jingning Han <jingning@google.com>
date: Tue Mar 5 05:45:16 EST 2019
Set up Wiener variance for macroblocks in a frame This commit introduces a Wiener variance term. For each block in the source frame, we first estimate its film grain noise level using median filter in the transform domain. Each transform coefficient is then processed using Wiener filter to account for the impact on the energy level due to film grain noise. The result leads to a second moment of the denoised signal. Change-Id: Ibce7cb1b0cb8fe1aba807d95289712271d576948
--- a/vp9/encoder/vp9_encoder.c
+++ b/vp9/encoder/vp9_encoder.c
@@ -116,6 +116,13 @@
}
#endif
+#if CONFIG_VP9_HIGHBITDEPTH
+void highbd_wht_fwd_txfm(int16_t *src_diff, int bw, tran_low_t *coeff,
+ TX_SIZE tx_size);
+#endif
+void wht_fwd_txfm(int16_t *src_diff, int bw, tran_low_t *coeff,
+ TX_SIZE tx_size);
+
// compute adaptive threshold for skip recoding
static int compute_context_model_thresh(const VP9_COMP *const cpi) {const VP9_COMMON *const cm = &cpi->common;
@@ -977,6 +984,12 @@
vpx_free(cpi->consec_zero_mv);
cpi->consec_zero_mv = NULL;
+ vpx_free(cpi->stack_rank_buffer);
+ cpi->stack_rank_buffer = NULL;
+
+ vpx_free(cpi->mb_wiener_variance);
+ cpi->mb_wiener_variance = NULL;
+
vp9_free_ref_frame_buffers(cm->buffer_pool);
#if CONFIG_VP9_POSTPROC
vp9_free_postproc_buffers(cm);
@@ -2367,6 +2380,14 @@
vp9_set_speed_features_framesize_independent(cpi);
vp9_set_speed_features_framesize_dependent(cpi);
+ if (cpi->sf.enable_wiener_variance) {+ CHECK_MEM_ERROR(cm, cpi->stack_rank_buffer,
+ vpx_calloc(UINT16_MAX, sizeof(*cpi->stack_rank_buffer)));
+ CHECK_MEM_ERROR(cm, cpi->mb_wiener_variance,
+ vpx_calloc(cm->mb_rows * cm->mb_cols,
+ sizeof(*cpi->mb_wiener_variance)));
+ }
+
#if CONFIG_NON_GREEDY_MV
cpi->feature_score_loc_alloc = 0;
cpi->tpl_ready = 0;
@@ -4691,6 +4712,97 @@
}
}
+// Process the wiener variance in 16x16 block basis.
+static void set_mb_wiener_variance(VP9_COMP *cpi) {+ VP9_COMMON *cm = &cpi->common;
+ uint8_t *buffer = cpi->Source->y_buffer;
+ int buf_stride = cpi->Source->y_stride;
+
+#if CONFIG_VP9_HIGHBITDEPTH
+ ThreadData *td = &cpi->td;
+ MACROBLOCK *x = &td->mb;
+ MACROBLOCKD *xd = &x->e_mbd;
+ DECLARE_ALIGNED(16, uint16_t, zero_pred16[32 * 32]);
+ DECLARE_ALIGNED(16, uint8_t, zero_pred8[32 * 32]);
+ uint8_t *zero_pred;
+#else
+ DECLARE_ALIGNED(16, uint8_t, zero_pred[32 * 32]);
+#endif
+
+ DECLARE_ALIGNED(16, int16_t, src_diff[32 * 32]);
+ DECLARE_ALIGNED(16, tran_low_t, coeff[32 * 32]);
+
+ int mb_row, mb_col;
+ // Hard coded operating block size
+ const int block_size = 16;
+ const int coeff_count = block_size * block_size;
+ const TX_SIZE tx_size = TX_16X16;
+
+ if (cpi->sf.enable_wiener_variance == 0) return;
+
+#if CONFIG_VP9_HIGHBITDEPTH
+ if (xd->cur_buf->flags & YV12_FLAG_HIGHBITDEPTH)
+ zero_pred = CONVERT_TO_BYTEPTR(zero_pred16);
+ else
+ zero_pred = zero_pred8;
+#endif
+
+ memset(zero_pred, 0, sizeof(*zero_pred) * coeff_count);
+
+ for (mb_row = 0; mb_row < cm->mb_rows; ++mb_row) {+ for (mb_col = 0; mb_col < cm->mb_cols; ++mb_col) {+ int idx, hist_count = 0;
+ int16_t median_val = 0;
+ uint8_t *mb_buffer =
+ buffer + mb_row * block_size * buf_stride + mb_col * block_size;
+ int64_t wiener_variance = 0;
+
+#if CONFIG_VP9_HIGHBITDEPTH
+ if (xd->cur_buf->flags & YV12_FLAG_HIGHBITDEPTH) {+ vpx_highbd_subtract_block(block_size, block_size, src_diff, block_size,
+ mb_buffer, buf_stride, zero_pred, block_size,
+ xd->bd);
+ highbd_wht_fwd_txfm(src_diff, block_size, coeff, tx_size);
+ } else {+ vpx_subtract_block(block_size, block_size, src_diff, block_size,
+ mb_buffer, buf_stride, zero_pred, block_size);
+ wht_fwd_txfm(src_diff, block_size, coeff, tx_size);
+ }
+#else
+ vpx_subtract_block(block_size, block_size, src_diff, block_size,
+ mb_buffer, buf_stride, zero_pred, block_size);
+ wht_fwd_txfm(src_diff, block_size, coeff, tx_size);
+#endif // CONFIG_VP9_HIGHBITDEPTH
+
+ for (idx = 0; idx < UINT16_MAX; ++idx) cpi->stack_rank_buffer[idx] = 0;
+
+ for (idx = 0; idx < coeff_count; ++idx)
+ ++cpi->stack_rank_buffer[abs(coeff[idx])];
+
+ for (idx = 0; idx < UINT16_MAX; ++idx) {+ hist_count += cpi->stack_rank_buffer[idx];
+ if (hist_count >= coeff_count / 2) break;
+ }
+
+ // Noise level estimation
+ median_val = idx;
+
+ // Wiener filter
+ for (idx = 1; idx < coeff_count; ++idx) {+ int sign = coeff[idx] < 0;
+ int64_t sqr_coeff = (int64_t)coeff[idx] * coeff[idx];
+ coeff[idx] = (int16_t)((sqr_coeff * coeff[idx]) /
+ (sqr_coeff + (int64_t)median_val * median_val));
+ if (sign) coeff[idx] = -coeff[idx];
+
+ wiener_variance += (int64_t)coeff[idx] * coeff[idx];
+ }
+ cpi->mb_wiener_variance[mb_row * cm->mb_cols + mb_col] =
+ wiener_variance / coeff_count;
+ }
+ }
+}
+
static void encode_frame_to_data_rate(VP9_COMP *cpi, size_t *size,
uint8_t *dest,
unsigned int *frame_flags) {@@ -4777,6 +4889,8 @@
}
}
+ set_mb_wiener_variance(cpi);
+
vpx_clear_system_state();
#if CONFIG_INTERNAL_STATS
@@ -5827,8 +5941,8 @@
}
#if CONFIG_VP9_HIGHBITDEPTH
-static void highbd_wht_fwd_txfm(int16_t *src_diff, int bw, tran_low_t *coeff,
- TX_SIZE tx_size) {+void highbd_wht_fwd_txfm(int16_t *src_diff, int bw, tran_low_t *coeff,
+ TX_SIZE tx_size) {// TODO(sdeng): Implement SIMD based high bit-depth Hadamard transforms.
switch (tx_size) {case TX_8X8: vpx_highbd_hadamard_8x8(src_diff, bw, coeff); break;
@@ -5839,8 +5953,8 @@
}
#endif // CONFIG_VP9_HIGHBITDEPTH
-static void wht_fwd_txfm(int16_t *src_diff, int bw, tran_low_t *coeff,
- TX_SIZE tx_size) {+void wht_fwd_txfm(int16_t *src_diff, int bw, tran_low_t *coeff,
+ TX_SIZE tx_size) { switch (tx_size) {case TX_8X8: vpx_hadamard_8x8(src_diff, bw, coeff); break;
case TX_16X16: vpx_hadamard_16x16(src_diff, bw, coeff); break;
--- a/vp9/encoder/vp9_encoder.h
+++ b/vp9/encoder/vp9_encoder.h
@@ -628,6 +628,9 @@
int ext_refresh_frame_context_pending;
int ext_refresh_frame_context;
+ int64_t *mb_wiener_variance;
+ int *stack_rank_buffer;
+
YV12_BUFFER_CONFIG last_frame_uf;
TOKENEXTRA *tile_tok[4][1 << 6];
--- a/vp9/encoder/vp9_speed_features.c
+++ b/vp9/encoder/vp9_speed_features.c
@@ -939,6 +939,10 @@
sf->tx_size_search_breakout = 1;
sf->tx_size_search_depth = 2;
+ // Manually turn this on during experimentation. Off by default to disable its
+ // effect on the baseline encoder.
+ sf->enable_wiener_variance = 0;
+
sf->exhaustive_searches_thresh =
(cpi->twopass.fr_content_type == FC_GRAPHICS_ANIMATION) ? (1 << 20)
: INT_MAX;
--- a/vp9/encoder/vp9_speed_features.h
+++ b/vp9/encoder/vp9_speed_features.h
@@ -288,6 +288,9 @@
// level within a frame.
int allow_skip_recode;
+ // Enable Wiener filter based block complexity analysis.
+ int enable_wiener_variance;
+
// Coefficient probability model approximation step size
int coeff_prob_appx_step;