diff options
Diffstat (limited to 'vp9/common/vp9_scale.c')
| -rw-r--r-- | vp9/common/vp9_scale.c | 149 |
1 files changed, 149 insertions, 0 deletions
diff --git a/vp9/common/vp9_scale.c b/vp9/common/vp9_scale.c new file mode 100644 index 000000000..3f0994f80 --- /dev/null +++ b/vp9/common/vp9_scale.c @@ -0,0 +1,149 @@ +/* + * Copyright (c) 2013 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 "./vp9_rtcd.h" +#include "vp9/common/vp9_filter.h" +#include "vp9/common/vp9_scale.h" + +static INLINE int scaled_x(int val, const struct scale_factors_common *sfc) { + return val * sfc->x_scale_fp >> REF_SCALE_SHIFT; +} + +static INLINE int scaled_y(int val, const struct scale_factors_common *sfc) { + return val * sfc->y_scale_fp >> REF_SCALE_SHIFT; +} + +static int unscaled_value(int val, const struct scale_factors_common *sfc) { + (void) sfc; + return val; +} + +static MV32 scaled_mv(const MV *mv, const struct scale_factors *scale) { + const MV32 res = { + scaled_y(mv->row, scale->sfc) + scale->y_offset_q4, + scaled_x(mv->col, scale->sfc) + scale->x_offset_q4 + }; + return res; +} + +static MV32 unscaled_mv(const MV *mv, const struct scale_factors *scale) { + const MV32 res = { + mv->row, + mv->col + }; + return res; +} + +static void set_offsets_with_scaling(struct scale_factors *scale, + int row, int col) { + scale->x_offset_q4 = scaled_x(col << SUBPEL_BITS, scale->sfc) & SUBPEL_MASK; + scale->y_offset_q4 = scaled_y(row << SUBPEL_BITS, scale->sfc) & SUBPEL_MASK; +} + +static void set_offsets_without_scaling(struct scale_factors *scale, + int row, int col) { + scale->x_offset_q4 = 0; + scale->y_offset_q4 = 0; +} + +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; +} + +static int check_scale_factors(int other_w, int other_h, + int this_w, int this_h) { + return 2 * this_w >= other_w && + 2 * this_h >= other_h && + this_w <= 16 * other_w && + this_h <= 16 * other_h; +} + +void vp9_setup_scale_factors_for_frame(struct scale_factors *scale, + struct scale_factors_common *scale_comm, + int other_w, int other_h, + int this_w, int this_h) { + if (!check_scale_factors(other_w, other_h, this_w, this_h)) { + scale_comm->x_scale_fp = REF_INVALID_SCALE; + scale_comm->y_scale_fp = REF_INVALID_SCALE; + return; + } + + scale_comm->x_scale_fp = get_fixed_point_scale_factor(other_w, this_w); + scale_comm->y_scale_fp = get_fixed_point_scale_factor(other_h, this_h); + scale_comm->x_step_q4 = scaled_x(16, scale_comm); + scale_comm->y_step_q4 = scaled_y(16, scale_comm); + + if (vp9_is_scaled(scale_comm)) { + scale_comm->scale_value_x = scaled_x; + scale_comm->scale_value_y = scaled_y; + scale_comm->set_scaled_offsets = set_offsets_with_scaling; + scale_comm->scale_mv = scaled_mv; + } else { + scale_comm->scale_value_x = unscaled_value; + scale_comm->scale_value_y = unscaled_value; + scale_comm->set_scaled_offsets = set_offsets_without_scaling; + scale_comm->scale_mv = unscaled_mv; + } + + // 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 (scale_comm->x_step_q4 == 16) { + if (scale_comm->y_step_q4 == 16) { + // No scaling in either direction. + scale_comm->predict[0][0][0] = vp9_convolve_copy; + scale_comm->predict[0][0][1] = vp9_convolve_avg; + scale_comm->predict[0][1][0] = vp9_convolve8_vert; + scale_comm->predict[0][1][1] = vp9_convolve8_avg_vert; + scale_comm->predict[1][0][0] = vp9_convolve8_horiz; + scale_comm->predict[1][0][1] = vp9_convolve8_avg_horiz; + } else { + // No scaling in x direction. Must always scale in the y direction. + scale_comm->predict[0][0][0] = vp9_convolve8_vert; + scale_comm->predict[0][0][1] = vp9_convolve8_avg_vert; + scale_comm->predict[0][1][0] = vp9_convolve8_vert; + scale_comm->predict[0][1][1] = vp9_convolve8_avg_vert; + scale_comm->predict[1][0][0] = vp9_convolve8; + scale_comm->predict[1][0][1] = vp9_convolve8_avg; + } + } else { + if (scale_comm->y_step_q4 == 16) { + // No scaling in the y direction. Must always scale in the x direction. + scale_comm->predict[0][0][0] = vp9_convolve8_horiz; + scale_comm->predict[0][0][1] = vp9_convolve8_avg_horiz; + scale_comm->predict[0][1][0] = vp9_convolve8; + scale_comm->predict[0][1][1] = vp9_convolve8_avg; + scale_comm->predict[1][0][0] = vp9_convolve8_horiz; + scale_comm->predict[1][0][1] = vp9_convolve8_avg_horiz; + } else { + // Must always scale in both directions. + scale_comm->predict[0][0][0] = vp9_convolve8; + scale_comm->predict[0][0][1] = vp9_convolve8_avg; + scale_comm->predict[0][1][0] = vp9_convolve8; + scale_comm->predict[0][1][1] = vp9_convolve8_avg; + scale_comm->predict[1][0][0] = vp9_convolve8; + scale_comm->predict[1][0][1] = vp9_convolve8_avg; + } + } + // 2D subpel motion always gets filtered in both directions + scale_comm->predict[1][1][0] = vp9_convolve8; + scale_comm->predict[1][1][1] = vp9_convolve8_avg; + + scale->sfc = scale_comm; + scale->x_offset_q4 = 0; // calculated per block + scale->y_offset_q4 = 0; // calculated per block +} |