libvpx: Add VP9 decoder.

source/libvpx/vp9/encoder/vp9_mbgraph.c

+/*
+ *  Copyright (c) 2010 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 <limits.h>
+#include <vp9/encoder/vp9_encodeintra.h>
+#include <vp9/encoder/vp9_rdopt.h>
+#include <vp9/common/vp9_setupintrarecon.h>
+#include <vp9/common/vp9_blockd.h>
+#include <vp9/common/vp9_reconinter.h>
+#include <vp9/common/vp9_systemdependent.h>
+#include <vpx_mem/vpx_mem.h>
+#include <vp9/encoder/vp9_segmentation.h>
+
+static unsigned int do_16x16_motion_iteration(VP9_COMP *cpi,
+                                              int_mv *ref_mv,
+                                              int_mv *dst_mv) {
+  MACROBLOCK   *const x  = &cpi->mb;
+  MACROBLOCKD *const xd = &x->e_mbd;
+  BLOCK *b  = &x->block[0];
+  BLOCKD *d = &xd->block[0];
+  vp9_variance_fn_ptr_t v_fn_ptr = cpi->fn_ptr[BLOCK_16X16];
+  unsigned int best_err;
+  int step_param, further_steps;
+
+  int tmp_col_min = x->mv_col_min;
+  int tmp_col_max = x->mv_col_max;
+  int tmp_row_min = x->mv_row_min;
+  int tmp_row_max = x->mv_row_max;
+  int_mv ref_full;
+
+  // Further step/diamond searches as necessary
+  if (cpi->Speed < 8) {
+    step_param = cpi->sf.first_step + ((cpi->Speed > 5) ? 1 : 0);
+    further_steps = (cpi->sf.max_step_search_steps - 1) - step_param;
+  } else {
+    step_param = cpi->sf.first_step + 2;
+    further_steps = 0;
+  }
+
+  vp9_clamp_mv_min_max(x, ref_mv);
+
+  ref_full.as_mv.col = ref_mv->as_mv.col >> 3;
+  ref_full.as_mv.row = ref_mv->as_mv.row >> 3;
+
+  /*cpi->sf.search_method == HEX*/
+  best_err = vp9_hex_search(
+      x, b, d,
+      &ref_full, dst_mv,
+      step_param,
+      x->errorperbit,
+      &v_fn_ptr,
+      NULL, NULL,
+      NULL, NULL,
+      ref_mv);
+
+  // Try sub-pixel MC
+  // if (bestsme > error_thresh && bestsme < INT_MAX)
+  {
+    int distortion;
+    unsigned int sse;
+    best_err = cpi->find_fractional_mv_step(
+        x, b, d,
+        dst_mv, ref_mv,
+        x->errorperbit, &v_fn_ptr,
+        NULL, NULL,
+        & distortion, &sse);
+  }
+
+#if CONFIG_PRED_FILTER
+  // Disable the prediction filter
+  xd->mode_info_context->mbmi.pred_filter_enabled = 0;
+#endif
+
+  vp9_set_mbmode_and_mvs(x, NEWMV, dst_mv);
+  vp9_build_1st_inter16x16_predictors_mby(xd, xd->predictor, 16, 0);
+  best_err = vp9_sad16x16(xd->dst.y_buffer, xd->dst.y_stride,
+                          xd->predictor, 16, INT_MAX);
+
+  /* restore UMV window */
+  x->mv_col_min = tmp_col_min;
+  x->mv_col_max = tmp_col_max;
+  x->mv_row_min = tmp_row_min;
+  x->mv_row_max = tmp_row_max;
+
+  return best_err;
+}
+
+static int do_16x16_motion_search
+(
+  VP9_COMP *cpi,
+  int_mv *ref_mv,
+  int_mv *dst_mv,
+  YV12_BUFFER_CONFIG *buf,
+  int buf_mb_y_offset,
+  YV12_BUFFER_CONFIG *ref,
+  int mb_y_offset
+) {
+  MACROBLOCK   *const x  = &cpi->mb;
+  MACROBLOCKD *const xd = &x->e_mbd;
+  unsigned int err, tmp_err;
+  int_mv tmp_mv;
+  int n;
+
+  for (n = 0; n < 16; n++) {
+    BLOCKD *d = &xd->block[n];
+    BLOCK *b  = &x->block[n];
+
+    b->base_src   = &buf->y_buffer;
+    b->src_stride = buf->y_stride;
+    b->src        = buf->y_stride * (n & 12) + (n & 3) * 4 + buf_mb_y_offset;
+
+    d->base_pre   = &ref->y_buffer;
+    d->pre_stride = ref->y_stride;
+    d->pre        = ref->y_stride * (n & 12) + (n & 3) * 4 + mb_y_offset;
+  }
+
+  // Try zero MV first
+  // FIXME should really use something like near/nearest MV and/or MV prediction
+  xd->pre.y_buffer = ref->y_buffer + mb_y_offset;
+  xd->pre.y_stride = ref->y_stride;
+  err = vp9_sad16x16(ref->y_buffer + mb_y_offset, ref->y_stride,
+                     xd->dst.y_buffer, xd->dst.y_stride, INT_MAX);
+  dst_mv->as_int = 0;
+
+  // Test last reference frame using the previous best mv as the
+  // starting point (best reference) for the search
+  tmp_err = do_16x16_motion_iteration(cpi, ref_mv, &tmp_mv);
+  if (tmp_err < err) {
+    err            = tmp_err;
+    dst_mv->as_int = tmp_mv.as_int;
+  }
+
+  // If the current best reference mv is not centred on 0,0 then do a 0,0 based search as well
+  if (ref_mv->as_int) {
+    unsigned int tmp_err;
+    int_mv zero_ref_mv, tmp_mv;
+
+    zero_ref_mv.as_int = 0;
+    tmp_err = do_16x16_motion_iteration(cpi, &zero_ref_mv, &tmp_mv);
+    if (tmp_err < err) {
+      dst_mv->as_int = tmp_mv.as_int;
+      err = tmp_err;
+    }
+  }
+
+  return err;
+}
+
+static int do_16x16_zerozero_search
+(
+  VP9_COMP *cpi,
+  int_mv *dst_mv,
+  YV12_BUFFER_CONFIG *buf,
+  int buf_mb_y_offset,
+  YV12_BUFFER_CONFIG *ref,
+  int mb_y_offset
+) {
+  MACROBLOCK   *const x  = &cpi->mb;
+  MACROBLOCKD *const xd = &x->e_mbd;
+  unsigned int err;
+  int n;
+
+  for (n = 0; n < 16; n++) {
+    BLOCKD *d = &xd->block[n];
+    BLOCK *b  = &x->block[n];
+
+    b->base_src   = &buf->y_buffer;
+    b->src_stride = buf->y_stride;
+    b->src        = buf->y_stride * (n & 12) + (n & 3) * 4 + buf_mb_y_offset;
+
+    d->base_pre   = &ref->y_buffer;
+    d->pre_stride = ref->y_stride;
+    d->pre        = ref->y_stride * (n & 12) + (n & 3) * 4 + mb_y_offset;
+  }
+
+  // Try zero MV first
+  // FIXME should really use something like near/nearest MV and/or MV prediction
+  xd->pre.y_buffer = ref->y_buffer + mb_y_offset;
+  xd->pre.y_stride = ref->y_stride;
+  err = vp9_sad16x16(ref->y_buffer + mb_y_offset, ref->y_stride,
+                     xd->dst.y_buffer, xd->dst.y_stride, INT_MAX);
+
+  dst_mv->as_int = 0;
+
+  return err;
+}
+static int find_best_16x16_intra
+(
+  VP9_COMP *cpi,
+  YV12_BUFFER_CONFIG *buf,
+  int mb_y_offset,
+  MB_PREDICTION_MODE *pbest_mode
+) {
+  MACROBLOCK   *const x  = &cpi->mb;
+  MACROBLOCKD *const xd = &x->e_mbd;
+  MB_PREDICTION_MODE best_mode = -1, mode;
+  unsigned int best_err = INT_MAX;
+
+  // calculate SATD for each intra prediction mode;
+  // we're intentionally not doing 4x4, we just want a rough estimate
+  for (mode = DC_PRED; mode <= TM_PRED; mode++) {
+    unsigned int err;
+
+    xd->mode_info_context->mbmi.mode = mode;
+    vp9_build_intra_predictors_mby(xd);
+    err = vp9_sad16x16(xd->predictor, 16, buf->y_buffer + mb_y_offset,
+                       buf->y_stride, best_err);
+    // find best
+    if (err < best_err) {
+      best_err  = err;
+      best_mode = mode;
+    }
+  }
+
+  if (pbest_mode)
+    *pbest_mode = best_mode;
+
+  return best_err;
+}
+
+static void update_mbgraph_mb_stats
+(
+  VP9_COMP *cpi,
+  MBGRAPH_MB_STATS *stats,
+  YV12_BUFFER_CONFIG *buf,
+  int mb_y_offset,
+  YV12_BUFFER_CONFIG *golden_ref,
+  int_mv *prev_golden_ref_mv,
+  int gld_y_offset,
+  YV12_BUFFER_CONFIG *alt_ref,
+  int_mv *prev_alt_ref_mv,
+  int arf_y_offset
+) {
+  MACROBLOCK   *const x  = &cpi->mb;
+  MACROBLOCKD *const xd = &x->e_mbd;
+  int intra_error;
+
+  // FIXME in practice we're completely ignoring chroma here
+  xd->dst.y_buffer = buf->y_buffer + mb_y_offset;
+
+  // do intra 16x16 prediction
+  intra_error = find_best_16x16_intra(cpi, buf, mb_y_offset, &stats->ref[INTRA_FRAME].m.mode);
+  if (intra_error <= 0)
+    intra_error = 1;
+  stats->ref[INTRA_FRAME].err = intra_error;
+
+  // Golden frame MV search, if it exists and is different than last frame
+  if (golden_ref) {
+    int g_motion_error = do_16x16_motion_search(cpi, prev_golden_ref_mv,
+                                                &stats->ref[GOLDEN_FRAME].m.mv,
+                                                buf, mb_y_offset,
+                                                golden_ref, gld_y_offset);
+    stats->ref[GOLDEN_FRAME].err = g_motion_error;
+  } else {
+    stats->ref[GOLDEN_FRAME].err = INT_MAX;
+    stats->ref[GOLDEN_FRAME].m.mv.as_int = 0;
+  }
+
+  // Alt-ref frame MV search, if it exists and is different than last/golden frame
+  if (alt_ref) {
+    // int a_motion_error = do_16x16_motion_search(cpi, prev_alt_ref_mv,
+    //                                            &stats->ref[ALTREF_FRAME].m.mv,
+    //                                            buf, mb_y_offset,
+    //                                            alt_ref, arf_y_offset);
+
+    int a_motion_error =
+      do_16x16_zerozero_search(cpi,
+                               &stats->ref[ALTREF_FRAME].m.mv,
+                               buf, mb_y_offset,
+                               alt_ref, arf_y_offset);
+
+    stats->ref[ALTREF_FRAME].err = a_motion_error;
+  } else {
+    stats->ref[ALTREF_FRAME].err = INT_MAX;
+    stats->ref[ALTREF_FRAME].m.mv.as_int = 0;
+  }
+}
+
+static void update_mbgraph_frame_stats
+(
+  VP9_COMP *cpi,
+  MBGRAPH_FRAME_STATS *stats,
+  YV12_BUFFER_CONFIG *buf,
+  YV12_BUFFER_CONFIG *golden_ref,
+  YV12_BUFFER_CONFIG *alt_ref
+) {
+  MACROBLOCK   *const x  = &cpi->mb;
+  VP9_COMMON   *const cm = &cpi->common;
+  MACROBLOCKD *const xd = &x->e_mbd;
+  int mb_col, mb_row, offset = 0;
+  int mb_y_offset = 0, arf_y_offset = 0, gld_y_offset = 0;
+  int_mv arf_top_mv, gld_top_mv;
+  MODE_INFO mi_local;
+
+  // Set up limit values for motion vectors to prevent them extending outside the UMV borders
+  arf_top_mv.as_int = 0;
+  gld_top_mv.as_int = 0;
+  x->mv_row_min     = -(VP9BORDERINPIXELS - 16 - VP9_INTERP_EXTEND);
+  x->mv_row_max     = (cm->mb_rows - 1) * 16 + VP9BORDERINPIXELS
+                      - 16 - VP9_INTERP_EXTEND;
+  xd->up_available  = 0;
+  xd->dst.y_stride  = buf->y_stride;
+  xd->pre.y_stride  = buf->y_stride;
+  xd->dst.uv_stride = buf->uv_stride;
+  xd->mode_info_context = &mi_local;
+
+  for (mb_row = 0; mb_row < cm->mb_rows; mb_row++) {
+    int_mv arf_left_mv, gld_left_mv;
+    int mb_y_in_offset  = mb_y_offset;
+    int arf_y_in_offset = arf_y_offset;
+    int gld_y_in_offset = gld_y_offset;
+
+    // Set up limit values for motion vectors to prevent them extending outside the UMV borders
+    arf_left_mv.as_int = arf_top_mv.as_int;
+    gld_left_mv.as_int = gld_top_mv.as_int;
+    x->mv_col_min      = -(VP9BORDERINPIXELS - 16 - VP9_INTERP_EXTEND);
+    x->mv_col_max      = (cm->mb_cols - 1) * 16 + VP9BORDERINPIXELS
+                         - 16 - VP9_INTERP_EXTEND;
+    xd->left_available = 0;
+
+    for (mb_col = 0; mb_col < cm->mb_cols; mb_col++) {
+      MBGRAPH_MB_STATS *mb_stats = &stats->mb_stats[offset + mb_col];
+
+      update_mbgraph_mb_stats(cpi, mb_stats, buf, mb_y_in_offset,
+                              golden_ref, &gld_left_mv, gld_y_in_offset,
+                              alt_ref,    &arf_left_mv, arf_y_in_offset);
+      arf_left_mv.as_int = mb_stats->ref[ALTREF_FRAME].m.mv.as_int;
+      gld_left_mv.as_int = mb_stats->ref[GOLDEN_FRAME].m.mv.as_int;
+      if (mb_col == 0) {
+        arf_top_mv.as_int = arf_left_mv.as_int;
+        gld_top_mv.as_int = gld_left_mv.as_int;
+      }
+      xd->left_available = 1;
+      mb_y_in_offset    += 16;
+      gld_y_in_offset   += 16;
+      arf_y_in_offset   += 16;
+      x->mv_col_min     -= 16;
+      x->mv_col_max     -= 16;
+    }
+    xd->up_available = 1;
+    mb_y_offset     += buf->y_stride * 16;
+    gld_y_offset    += golden_ref->y_stride * 16;
+    if (alt_ref)
+      arf_y_offset    += alt_ref->y_stride * 16;
+    x->mv_row_min   -= 16;
+    x->mv_row_max   -= 16;
+    offset          += cm->mb_cols;
+  }
+}
+
+// void separate_arf_mbs_byzz
+static void separate_arf_mbs(VP9_COMP *cpi) {
+  VP9_COMMON *const cm = &cpi->common;
+  int mb_col, mb_row, offset, i;
+  int ncnt[4];
+  int n_frames = cpi->mbgraph_n_frames;
+
+  int *arf_not_zz;
+
+  CHECK_MEM_ERROR(arf_not_zz,
+                  vpx_calloc(cm->mb_rows * cm->mb_cols * sizeof(*arf_not_zz), 1));
+
+  // We are not interested in results beyond the alt ref itself.
+  if (n_frames > cpi->frames_till_gf_update_due)
+    n_frames = cpi->frames_till_gf_update_due;
+
+  // defer cost to reference frames
+  for (i = n_frames - 1; i >= 0; i--) {
+    MBGRAPH_FRAME_STATS *frame_stats = &cpi->mbgraph_stats[i];
+
+    for (offset = 0, mb_row = 0; mb_row < cm->mb_rows;
+         offset += cm->mb_cols, mb_row++) {
+      for (mb_col = 0; mb_col < cm->mb_cols; mb_col++) {
+        MBGRAPH_MB_STATS *mb_stats =
+          &frame_stats->mb_stats[offset + mb_col];
+
+        int altref_err = mb_stats->ref[ALTREF_FRAME].err;
+        int intra_err  = mb_stats->ref[INTRA_FRAME ].err;
+        int golden_err = mb_stats->ref[GOLDEN_FRAME].err;
+
+        // Test for altref vs intra and gf and that its mv was 0,0.
+        if ((altref_err > 1000) ||
+            (altref_err > intra_err) ||
+            (altref_err > golden_err)) {
+          arf_not_zz[offset + mb_col]++;
+        }
+      }
+    }
+  }
+
+  vpx_memset(ncnt, 0, sizeof(ncnt));
+  for (offset = 0, mb_row = 0; mb_row < cm->mb_rows;
+       offset += cm->mb_cols, mb_row++) {
+    for (mb_col = 0; mb_col < cm->mb_cols; mb_col++) {
+      // If any of the blocks in the sequence failed then the MB
+      // goes in segment 0
+      if (arf_not_zz[offset + mb_col]) {
+        ncnt[0]++;
+        cpi->segmentation_map[offset + mb_col] = 0;
+      } else {
+        ncnt[1]++;
+        cpi->segmentation_map[offset + mb_col] = 1;
+      }
+    }
+  }
+
+  // Only bother with segmentation if over 10% of the MBs in static segment
+  // if ( ncnt[1] && (ncnt[0] / ncnt[1] < 10) )
+  if (1) {
+    // Note % of blocks that are marked as static
+    if (cm->MBs)
+      cpi->static_mb_pct = (ncnt[1] * 100) / cm->MBs;
+
+    // This error case should not be reachable as this function should
+    // never be called with the common data structure unititialized.
+    else
+      cpi->static_mb_pct = 0;
+
+    cpi->seg0_cnt = ncnt[0];
+    vp9_enable_segmentation((VP9_PTR) cpi);
+  } else {
+    cpi->static_mb_pct = 0;
+    vp9_disable_segmentation((VP9_PTR) cpi);
+  }
+
+  // Free localy allocated storage
+  vpx_free(arf_not_zz);
+}
+
+void vp9_update_mbgraph_stats
+(
+  VP9_COMP *cpi
+) {
+  VP9_COMMON *const cm = &cpi->common;
+  int i, n_frames = vp9_lookahead_depth(cpi->lookahead);
+  YV12_BUFFER_CONFIG *golden_ref = &cm->yv12_fb[cm->gld_fb_idx];
+
+  // we need to look ahead beyond where the ARF transitions into
+  // being a GF - so exit if we don't look ahead beyond that
+  if (n_frames <= cpi->frames_till_gf_update_due)
+    return;
+  if (n_frames > (int)cpi->common.frames_till_alt_ref_frame)
+    n_frames = cpi->common.frames_till_alt_ref_frame;
+  if (n_frames > MAX_LAG_BUFFERS)
+    n_frames = MAX_LAG_BUFFERS;
+
+  cpi->mbgraph_n_frames = n_frames;
+  for (i = 0; i < n_frames; i++) {
+    MBGRAPH_FRAME_STATS *frame_stats = &cpi->mbgraph_stats[i];
+    vpx_memset(frame_stats->mb_stats, 0,
+               cm->mb_rows * cm->mb_cols * sizeof(*cpi->mbgraph_stats[i].mb_stats));
+  }
+
+  // do motion search to find contribution of each reference to data
+  // later on in this GF group
+  // FIXME really, the GF/last MC search should be done forward, and
+  // the ARF MC search backwards, to get optimal results for MV caching
+  for (i = 0; i < n_frames; i++) {
+    MBGRAPH_FRAME_STATS *frame_stats = &cpi->mbgraph_stats[i];
+    struct lookahead_entry *q_cur =
+      vp9_lookahead_peek(cpi->lookahead, i);
+
+    assert(q_cur != NULL);
+
+    update_mbgraph_frame_stats(cpi, frame_stats, &q_cur->img,
+                               golden_ref, cpi->Source);
+  }
+
+  vp9_clear_system_state();  // __asm emms;
+
+  separate_arf_mbs(cpi);
+}