Import aom library

This is the reference implementation for the Alliance for Open Media's av1 video code.

The commit used was 4d668d7feb1f8abd809d1bca0418570a7f142a36.

1 files changed, 164 insertions, 0 deletions

diff --git a/third_party/aom/av1/common/scale.c b/third_party/aom/av1/common/scale.c
new file mode 100644
index 000000000..76beaa2bd
--- /dev/null
+++ b/third_party/aom/av1/common/scale.c
@@ -0,0 +1,164 @@
+/*
+ * Copyright (c) 2016, Alliance for Open Media. All rights reserved
+ *
+ * This source code is subject to the terms of the BSD 2 Clause License and
+ * the Alliance for Open Media Patent License 1.0. If the BSD 2 Clause License
+ * was not distributed with this source code in the LICENSE file, you can
+ * obtain it at www.aomedia.org/license/software. If the Alliance for Open
+ * Media Patent License 1.0 was not distributed with this source code in the
+ * PATENTS file, you can obtain it at www.aomedia.org/license/patent.
+ */
+
+#include "./aom_dsp_rtcd.h"
+#include "av1/common/filter.h"
+#include "av1/common/scale.h"
+#include "aom_dsp/aom_filter.h"
+
+static INLINE int scaled_x(int val, const struct scale_factors *sf) {
+  return (int)((int64_t)val * sf->x_scale_fp >> REF_SCALE_SHIFT);
+}
+
+static INLINE int scaled_y(int val, const struct scale_factors *sf) {
+  return (int)((int64_t)val * sf->y_scale_fp >> REF_SCALE_SHIFT);
+}
+
+static int unscaled_value(int val, const struct scale_factors *sf) {
+  (void)sf;
+  return val;
+}
+
+static int get_fixed_point_scale_factor(int other_size, int this_size) {
+  // Calculate scaling factor once for each reference frame
+  // and use fixed point scaling factors in decoding and encoding routines.
+  // Hardware implementations can calculate scale factor in device driver
+  // and use multiplication and shifting on hardware instead of division.
+  return (other_size << REF_SCALE_SHIFT) / this_size;
+}
+
+MV32 av1_scale_mv(const MV *mv, int x, int y, const struct scale_factors *sf) {
+  const int x_off_q4 = scaled_x(x << SUBPEL_BITS, sf) & SUBPEL_MASK;
+  const int y_off_q4 = scaled_y(y << SUBPEL_BITS, sf) & SUBPEL_MASK;
+  const MV32 res = { scaled_y(mv->row, sf) + y_off_q4,
+                     scaled_x(mv->col, sf) + x_off_q4 };
+  return res;
+}
+
+#if CONFIG_HIGHBITDEPTH
+void av1_setup_scale_factors_for_frame(struct scale_factors *sf, int other_w,
+                                       int other_h, int this_w, int this_h,
+                                       int use_highbd) {
+#else
+void av1_setup_scale_factors_for_frame(struct scale_factors *sf, int other_w,
+                                       int other_h, int this_w, int this_h) {
+#endif
+  if (!valid_ref_frame_size(other_w, other_h, this_w, this_h)) {
+    sf->x_scale_fp = REF_INVALID_SCALE;
+    sf->y_scale_fp = REF_INVALID_SCALE;
+    return;
+  }
+
+  sf->x_scale_fp = get_fixed_point_scale_factor(other_w, this_w);
+  sf->y_scale_fp = get_fixed_point_scale_factor(other_h, this_h);
+  sf->x_step_q4 = scaled_x(16, sf);
+  sf->y_step_q4 = scaled_y(16, sf);
+
+  if (av1_is_scaled(sf)) {
+    sf->scale_value_x = scaled_x;
+    sf->scale_value_y = scaled_y;
+  } else {
+    sf->scale_value_x = unscaled_value;
+    sf->scale_value_y = unscaled_value;
+  }
+
+  // TODO(agrange): Investigate the best choice of functions to use here
+  // for EIGHTTAP_SMOOTH. Since it is not interpolating, need to choose what
+  // to do at full-pel offsets. The current selection, where the filter is
+  // applied in one direction only, and not at all for 0,0, seems to give the
+  // best quality, but it may be worth trying an additional mode that does
+  // do the filtering on full-pel.
+  if (sf->x_step_q4 == 16) {
+    if (sf->y_step_q4 == 16) {
+      // No scaling in either direction.
+      sf->predict[0][0][0] = aom_convolve_copy;
+      sf->predict[0][0][1] = aom_convolve_avg;
+      sf->predict[0][1][0] = aom_convolve8_vert;
+      sf->predict[0][1][1] = aom_convolve8_avg_vert;
+      sf->predict[1][0][0] = aom_convolve8_horiz;
+      sf->predict[1][0][1] = aom_convolve8_avg_horiz;
+    } else {
+      // No scaling in x direction. Must always scale in the y direction.
+      sf->predict[0][0][0] = aom_convolve8_vert;
+      sf->predict[0][0][1] = aom_convolve8_avg_vert;
+      sf->predict[0][1][0] = aom_convolve8_vert;
+      sf->predict[0][1][1] = aom_convolve8_avg_vert;
+      sf->predict[1][0][0] = aom_convolve8;
+      sf->predict[1][0][1] = aom_convolve8_avg;
+    }
+  } else {
+    if (sf->y_step_q4 == 16) {
+      // No scaling in the y direction. Must always scale in the x direction.
+      sf->predict[0][0][0] = aom_convolve8_horiz;
+      sf->predict[0][0][1] = aom_convolve8_avg_horiz;
+      sf->predict[0][1][0] = aom_convolve8;
+      sf->predict[0][1][1] = aom_convolve8_avg;
+      sf->predict[1][0][0] = aom_convolve8_horiz;
+      sf->predict[1][0][1] = aom_convolve8_avg_horiz;
+    } else {
+      // Must always scale in both directions.
+      sf->predict[0][0][0] = aom_convolve8;
+      sf->predict[0][0][1] = aom_convolve8_avg;
+      sf->predict[0][1][0] = aom_convolve8;
+      sf->predict[0][1][1] = aom_convolve8_avg;
+      sf->predict[1][0][0] = aom_convolve8;
+      sf->predict[1][0][1] = aom_convolve8_avg;
+    }
+  }
+  // 2D subpel motion always gets filtered in both directions
+  sf->predict[1][1][0] = aom_convolve8;
+  sf->predict[1][1][1] = aom_convolve8_avg;
+
+#if CONFIG_HIGHBITDEPTH
+  if (use_highbd) {
+    if (sf->x_step_q4 == 16) {
+      if (sf->y_step_q4 == 16) {
+        // No scaling in either direction.
+        sf->highbd_predict[0][0][0] = aom_highbd_convolve_copy;
+        sf->highbd_predict[0][0][1] = aom_highbd_convolve_avg;
+        sf->highbd_predict[0][1][0] = aom_highbd_convolve8_vert;
+        sf->highbd_predict[0][1][1] = aom_highbd_convolve8_avg_vert;
+        sf->highbd_predict[1][0][0] = aom_highbd_convolve8_horiz;
+        sf->highbd_predict[1][0][1] = aom_highbd_convolve8_avg_horiz;
+      } else {
+        // No scaling in x direction. Must always scale in the y direction.
+        sf->highbd_predict[0][0][0] = aom_highbd_convolve8_vert;
+        sf->highbd_predict[0][0][1] = aom_highbd_convolve8_avg_vert;
+        sf->highbd_predict[0][1][0] = aom_highbd_convolve8_vert;
+        sf->highbd_predict[0][1][1] = aom_highbd_convolve8_avg_vert;
+        sf->highbd_predict[1][0][0] = aom_highbd_convolve8;
+        sf->highbd_predict[1][0][1] = aom_highbd_convolve8_avg;
+      }
+    } else {
+      if (sf->y_step_q4 == 16) {
+        // No scaling in the y direction. Must always scale in the x direction.
+        sf->highbd_predict[0][0][0] = aom_highbd_convolve8_horiz;
+        sf->highbd_predict[0][0][1] = aom_highbd_convolve8_avg_horiz;
+        sf->highbd_predict[0][1][0] = aom_highbd_convolve8;
+        sf->highbd_predict[0][1][1] = aom_highbd_convolve8_avg;
+        sf->highbd_predict[1][0][0] = aom_highbd_convolve8_horiz;
+        sf->highbd_predict[1][0][1] = aom_highbd_convolve8_avg_horiz;
+      } else {
+        // Must always scale in both directions.
+        sf->highbd_predict[0][0][0] = aom_highbd_convolve8;
+        sf->highbd_predict[0][0][1] = aom_highbd_convolve8_avg;
+        sf->highbd_predict[0][1][0] = aom_highbd_convolve8;
+        sf->highbd_predict[0][1][1] = aom_highbd_convolve8_avg;
+        sf->highbd_predict[1][0][0] = aom_highbd_convolve8;
+        sf->highbd_predict[1][0][1] = aom_highbd_convolve8_avg;
+      }
+    }
+    // 2D subpel motion always gets filtered in both directions.
+    sf->highbd_predict[1][1][0] = aom_highbd_convolve8;
+    sf->highbd_predict[1][1][1] = aom_highbd_convolve8_avg;
+  }
+#endif  // CONFIG_HIGHBITDEPTH
+}