vp9_resize.c 31.5 KB
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/*
 *  Copyright (c) 2014 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 <assert.h>
#include <limits.h>
#include <math.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
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#include "./vpx_config.h"
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#if CONFIG_VP9_HIGHBITDEPTH
#include "vpx_dsp/vpx_dsp_common.h"
#endif  // CONFIG_VP9_HIGHBITDEPTH
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#include "vpx_ports/mem.h"
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#include "vp9/common/vp9_common.h"
#include "vp9/encoder/vp9_resize.h"

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#define FILTER_BITS 7
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#define INTERP_TAPS 8
#define SUBPEL_BITS 5
#define SUBPEL_MASK ((1 << SUBPEL_BITS) - 1)
#define INTERP_PRECISION_BITS 32
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typedef int16_t interp_kernel[INTERP_TAPS];

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// Filters for interpolation (0.5-band) - note this also filters integer pels.
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static const interp_kernel filteredinterp_filters500[(1 << SUBPEL_BITS)] = {
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  { -3, 0, 35, 64, 35, 0, -3, 0 },    { -3, -1, 34, 64, 36, 1, -3, 0 },
  { -3, -1, 32, 64, 38, 1, -3, 0 },   { -2, -2, 31, 63, 39, 2, -3, 0 },
  { -2, -2, 29, 63, 41, 2, -3, 0 },   { -2, -2, 28, 63, 42, 3, -4, 0 },
  { -2, -3, 27, 63, 43, 4, -4, 0 },   { -2, -3, 25, 62, 45, 5, -4, 0 },
  { -2, -3, 24, 62, 46, 5, -4, 0 },   { -2, -3, 23, 61, 47, 6, -4, 0 },
  { -2, -3, 21, 60, 49, 7, -4, 0 },   { -1, -4, 20, 60, 50, 8, -4, -1 },
  { -1, -4, 19, 59, 51, 9, -4, -1 },  { -1, -4, 17, 58, 52, 10, -4, 0 },
  { -1, -4, 16, 57, 53, 12, -4, -1 }, { -1, -4, 15, 56, 54, 13, -4, -1 },
  { -1, -4, 14, 55, 55, 14, -4, -1 }, { -1, -4, 13, 54, 56, 15, -4, -1 },
  { -1, -4, 12, 53, 57, 16, -4, -1 }, { 0, -4, 10, 52, 58, 17, -4, -1 },
  { -1, -4, 9, 51, 59, 19, -4, -1 },  { -1, -4, 8, 50, 60, 20, -4, -1 },
  { 0, -4, 7, 49, 60, 21, -3, -2 },   { 0, -4, 6, 47, 61, 23, -3, -2 },
  { 0, -4, 5, 46, 62, 24, -3, -2 },   { 0, -4, 5, 45, 62, 25, -3, -2 },
  { 0, -4, 4, 43, 63, 27, -3, -2 },   { 0, -4, 3, 42, 63, 28, -2, -2 },
  { 0, -3, 2, 41, 63, 29, -2, -2 },   { 0, -3, 2, 39, 63, 31, -2, -2 },
  { 0, -3, 1, 38, 64, 32, -1, -3 },   { 0, -3, 1, 36, 64, 34, -1, -3 }
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};

// Filters for interpolation (0.625-band) - note this also filters integer pels.
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static const interp_kernel filteredinterp_filters625[(1 << SUBPEL_BITS)] = {
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  { -1, -8, 33, 80, 33, -8, -1, 0 }, { -1, -8, 30, 80, 35, -8, -1, 1 },
  { -1, -8, 28, 80, 37, -7, -2, 1 }, { 0, -8, 26, 79, 39, -7, -2, 1 },
  { 0, -8, 24, 79, 41, -7, -2, 1 },  { 0, -8, 22, 78, 43, -6, -2, 1 },
  { 0, -8, 20, 78, 45, -5, -3, 1 },  { 0, -8, 18, 77, 48, -5, -3, 1 },
  { 0, -8, 16, 76, 50, -4, -3, 1 },  { 0, -8, 15, 75, 52, -3, -4, 1 },
  { 0, -7, 13, 74, 54, -3, -4, 1 },  { 0, -7, 11, 73, 56, -2, -4, 1 },
  { 0, -7, 10, 71, 58, -1, -4, 1 },  { 1, -7, 8, 70, 60, 0, -5, 1 },
  { 1, -6, 6, 68, 62, 1, -5, 1 },    { 1, -6, 5, 67, 63, 2, -5, 1 },
  { 1, -6, 4, 65, 65, 4, -6, 1 },    { 1, -5, 2, 63, 67, 5, -6, 1 },
  { 1, -5, 1, 62, 68, 6, -6, 1 },    { 1, -5, 0, 60, 70, 8, -7, 1 },
  { 1, -4, -1, 58, 71, 10, -7, 0 },  { 1, -4, -2, 56, 73, 11, -7, 0 },
  { 1, -4, -3, 54, 74, 13, -7, 0 },  { 1, -4, -3, 52, 75, 15, -8, 0 },
  { 1, -3, -4, 50, 76, 16, -8, 0 },  { 1, -3, -5, 48, 77, 18, -8, 0 },
  { 1, -3, -5, 45, 78, 20, -8, 0 },  { 1, -2, -6, 43, 78, 22, -8, 0 },
  { 1, -2, -7, 41, 79, 24, -8, 0 },  { 1, -2, -7, 39, 79, 26, -8, 0 },
  { 1, -2, -7, 37, 80, 28, -8, -1 }, { 1, -1, -8, 35, 80, 30, -8, -1 },
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};

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// Filters for interpolation (0.75-band) - note this also filters integer pels.
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static const interp_kernel filteredinterp_filters750[(1 << SUBPEL_BITS)] = {
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  { 2, -11, 25, 96, 25, -11, 2, 0 }, { 2, -11, 22, 96, 28, -11, 2, 0 },
  { 2, -10, 19, 95, 31, -11, 2, 0 }, { 2, -10, 17, 95, 34, -12, 2, 0 },
  { 2, -9, 14, 94, 37, -12, 2, 0 },  { 2, -8, 12, 93, 40, -12, 1, 0 },
  { 2, -8, 9, 92, 43, -12, 1, 1 },   { 2, -7, 7, 91, 46, -12, 1, 0 },
  { 2, -7, 5, 90, 49, -12, 1, 0 },   { 2, -6, 3, 88, 52, -12, 0, 1 },
  { 2, -5, 1, 86, 55, -12, 0, 1 },   { 2, -5, -1, 84, 58, -11, 0, 1 },
  { 2, -4, -2, 82, 61, -11, -1, 1 }, { 2, -4, -4, 80, 64, -10, -1, 1 },
  { 1, -3, -5, 77, 67, -9, -1, 1 },  { 1, -3, -6, 75, 70, -8, -2, 1 },
  { 1, -2, -7, 72, 72, -7, -2, 1 },  { 1, -2, -8, 70, 75, -6, -3, 1 },
  { 1, -1, -9, 67, 77, -5, -3, 1 },  { 1, -1, -10, 64, 80, -4, -4, 2 },
  { 1, -1, -11, 61, 82, -2, -4, 2 }, { 1, 0, -11, 58, 84, -1, -5, 2 },
  { 1, 0, -12, 55, 86, 1, -5, 2 },   { 1, 0, -12, 52, 88, 3, -6, 2 },
  { 0, 1, -12, 49, 90, 5, -7, 2 },   { 0, 1, -12, 46, 91, 7, -7, 2 },
  { 1, 1, -12, 43, 92, 9, -8, 2 },   { 0, 1, -12, 40, 93, 12, -8, 2 },
  { 0, 2, -12, 37, 94, 14, -9, 2 },  { 0, 2, -12, 34, 95, 17, -10, 2 },
  { 0, 2, -11, 31, 95, 19, -10, 2 }, { 0, 2, -11, 28, 96, 22, -11, 2 }
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};

// Filters for interpolation (0.875-band) - note this also filters integer pels.
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static const interp_kernel filteredinterp_filters875[(1 << SUBPEL_BITS)] = {
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  { 3, -8, 13, 112, 13, -8, 3, 0 },   { 3, -7, 10, 112, 17, -9, 3, -1 },
  { 2, -6, 7, 111, 21, -9, 3, -1 },   { 2, -5, 4, 111, 24, -10, 3, -1 },
  { 2, -4, 1, 110, 28, -11, 3, -1 },  { 1, -3, -1, 108, 32, -12, 4, -1 },
  { 1, -2, -3, 106, 36, -13, 4, -1 }, { 1, -1, -6, 105, 40, -14, 4, -1 },
  { 1, -1, -7, 102, 44, -14, 4, -1 }, { 1, 0, -9, 100, 48, -15, 4, -1 },
  { 1, 1, -11, 97, 53, -16, 4, -1 },  { 0, 1, -12, 95, 57, -16, 4, -1 },
  { 0, 2, -13, 91, 61, -16, 4, -1 },  { 0, 2, -14, 88, 65, -16, 4, -1 },
  { 0, 3, -15, 84, 69, -17, 4, 0 },   { 0, 3, -16, 81, 73, -16, 3, 0 },
  { 0, 3, -16, 77, 77, -16, 3, 0 },   { 0, 3, -16, 73, 81, -16, 3, 0 },
  { 0, 4, -17, 69, 84, -15, 3, 0 },   { -1, 4, -16, 65, 88, -14, 2, 0 },
  { -1, 4, -16, 61, 91, -13, 2, 0 },  { -1, 4, -16, 57, 95, -12, 1, 0 },
  { -1, 4, -16, 53, 97, -11, 1, 1 },  { -1, 4, -15, 48, 100, -9, 0, 1 },
  { -1, 4, -14, 44, 102, -7, -1, 1 }, { -1, 4, -14, 40, 105, -6, -1, 1 },
  { -1, 4, -13, 36, 106, -3, -2, 1 }, { -1, 4, -12, 32, 108, -1, -3, 1 },
  { -1, 3, -11, 28, 110, 1, -4, 2 },  { -1, 3, -10, 24, 111, 4, -5, 2 },
  { -1, 3, -9, 21, 111, 7, -6, 2 },   { -1, 3, -9, 17, 112, 10, -7, 3 }
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};

// Filters for interpolation (full-band) - no filtering for integer pixels
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static const interp_kernel filteredinterp_filters1000[(1 << SUBPEL_BITS)] = {
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  { 0, 0, 0, 128, 0, 0, 0, 0 },        { 0, 1, -3, 128, 3, -1, 0, 0 },
  { -1, 2, -6, 127, 7, -2, 1, 0 },     { -1, 3, -9, 126, 12, -4, 1, 0 },
  { -1, 4, -12, 125, 16, -5, 1, 0 },   { -1, 4, -14, 123, 20, -6, 2, 0 },
  { -1, 5, -15, 120, 25, -8, 2, 0 },   { -1, 5, -17, 118, 30, -9, 3, -1 },
  { -1, 6, -18, 114, 35, -10, 3, -1 }, { -1, 6, -19, 111, 41, -12, 3, -1 },
  { -1, 6, -20, 107, 46, -13, 4, -1 }, { -1, 6, -21, 103, 52, -14, 4, -1 },
  { -1, 6, -21, 99, 57, -16, 5, -1 },  { -1, 6, -21, 94, 63, -17, 5, -1 },
  { -1, 6, -20, 89, 68, -18, 5, -1 },  { -1, 6, -20, 84, 73, -19, 6, -1 },
  { -1, 6, -20, 79, 79, -20, 6, -1 },  { -1, 6, -19, 73, 84, -20, 6, -1 },
  { -1, 5, -18, 68, 89, -20, 6, -1 },  { -1, 5, -17, 63, 94, -21, 6, -1 },
  { -1, 5, -16, 57, 99, -21, 6, -1 },  { -1, 4, -14, 52, 103, -21, 6, -1 },
  { -1, 4, -13, 46, 107, -20, 6, -1 }, { -1, 3, -12, 41, 111, -19, 6, -1 },
  { -1, 3, -10, 35, 114, -18, 6, -1 }, { -1, 3, -9, 30, 118, -17, 5, -1 },
  { 0, 2, -8, 25, 120, -15, 5, -1 },   { 0, 2, -6, 20, 123, -14, 4, -1 },
  { 0, 1, -5, 16, 125, -12, 4, -1 },   { 0, 1, -4, 12, 126, -9, 3, -1 },
  { 0, 1, -2, 7, 127, -6, 2, -1 },     { 0, 0, -1, 3, 128, -3, 1, 0 }
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};

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// Filters for factor of 2 downsampling.
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static const int16_t vp9_down2_symeven_half_filter[] = { 56, 12, -3, -1 };
static const int16_t vp9_down2_symodd_half_filter[] = { 64, 35, 0, -3 };
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static const interp_kernel *choose_interp_filter(int inlength, int outlength) {
  int outlength16 = outlength * 16;
  if (outlength16 >= inlength * 16)
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    return filteredinterp_filters1000;
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  else if (outlength16 >= inlength * 13)
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    return filteredinterp_filters875;
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  else if (outlength16 >= inlength * 11)
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    return filteredinterp_filters750;
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  else if (outlength16 >= inlength * 9)
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    return filteredinterp_filters625;
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  else
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    return filteredinterp_filters500;
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}

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static void interpolate(const uint8_t *const input, int inlength,
                        uint8_t *output, int outlength) {
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  const int64_t delta =
      (((uint64_t)inlength << 32) + outlength / 2) / outlength;
  const int64_t offset =
      inlength > outlength
          ? (((int64_t)(inlength - outlength) << 31) + outlength / 2) /
                outlength
          : -(((int64_t)(outlength - inlength) << 31) + outlength / 2) /
                outlength;
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  uint8_t *optr = output;
  int x, x1, x2, sum, k, int_pel, sub_pel;
  int64_t y;

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  const interp_kernel *interp_filters =
      choose_interp_filter(inlength, outlength);

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  x = 0;
  y = offset;
  while ((y >> INTERP_PRECISION_BITS) < (INTERP_TAPS / 2 - 1)) {
    x++;
    y += delta;
  }
  x1 = x;
  x = outlength - 1;
  y = delta * x + offset;
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  while ((y >> INTERP_PRECISION_BITS) + (int64_t)(INTERP_TAPS / 2) >=
         inlength) {
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    x--;
    y -= delta;
  }
  x2 = x;
  if (x1 > x2) {
    for (x = 0, y = offset; x < outlength; ++x, y += delta) {
      const int16_t *filter;
      int_pel = y >> INTERP_PRECISION_BITS;
      sub_pel = (y >> (INTERP_PRECISION_BITS - SUBPEL_BITS)) & SUBPEL_MASK;
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      filter = interp_filters[sub_pel];
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      sum = 0;
      for (k = 0; k < INTERP_TAPS; ++k) {
        const int pk = int_pel - INTERP_TAPS / 2 + 1 + k;
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        sum += filter[k] *
               input[(pk < 0 ? 0 : (pk >= inlength ? inlength - 1 : pk))];
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      }
      *optr++ = clip_pixel(ROUND_POWER_OF_TWO(sum, FILTER_BITS));
    }
  } else {
    // Initial part.
    for (x = 0, y = offset; x < x1; ++x, y += delta) {
      const int16_t *filter;
      int_pel = y >> INTERP_PRECISION_BITS;
      sub_pel = (y >> (INTERP_PRECISION_BITS - SUBPEL_BITS)) & SUBPEL_MASK;
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      filter = interp_filters[sub_pel];
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      sum = 0;
      for (k = 0; k < INTERP_TAPS; ++k)
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        sum += filter[k] * input[(int_pel - INTERP_TAPS / 2 + 1 + k < 0
                                      ? 0
                                      : int_pel - INTERP_TAPS / 2 + 1 + k)];
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      *optr++ = clip_pixel(ROUND_POWER_OF_TWO(sum, FILTER_BITS));
    }
    // Middle part.
    for (; x <= x2; ++x, y += delta) {
      const int16_t *filter;
      int_pel = y >> INTERP_PRECISION_BITS;
      sub_pel = (y >> (INTERP_PRECISION_BITS - SUBPEL_BITS)) & SUBPEL_MASK;
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      filter = interp_filters[sub_pel];
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      sum = 0;
      for (k = 0; k < INTERP_TAPS; ++k)
        sum += filter[k] * input[int_pel - INTERP_TAPS / 2 + 1 + k];
      *optr++ = clip_pixel(ROUND_POWER_OF_TWO(sum, FILTER_BITS));
    }
    // End part.
    for (; x < outlength; ++x, y += delta) {
      const int16_t *filter;
      int_pel = y >> INTERP_PRECISION_BITS;
      sub_pel = (y >> (INTERP_PRECISION_BITS - SUBPEL_BITS)) & SUBPEL_MASK;
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      filter = interp_filters[sub_pel];
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      sum = 0;
      for (k = 0; k < INTERP_TAPS; ++k)
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        sum += filter[k] * input[(int_pel - INTERP_TAPS / 2 + 1 + k >= inlength
                                      ? inlength - 1
                                      : int_pel - INTERP_TAPS / 2 + 1 + k)];
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      *optr++ = clip_pixel(ROUND_POWER_OF_TWO(sum, FILTER_BITS));
    }
  }
}

static void down2_symeven(const uint8_t *const input, int length,
                          uint8_t *output) {
  // Actual filter len = 2 * filter_len_half.
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  const int16_t *filter = vp9_down2_symeven_half_filter;
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  const int filter_len_half = sizeof(vp9_down2_symeven_half_filter) / 2;
  int i, j;
  uint8_t *optr = output;
  int l1 = filter_len_half;
  int l2 = (length - filter_len_half);
  l1 += (l1 & 1);
  l2 += (l2 & 1);
  if (l1 > l2) {
    // Short input length.
    for (i = 0; i < length; i += 2) {
      int sum = (1 << (FILTER_BITS - 1));
      for (j = 0; j < filter_len_half; ++j) {
        sum += (input[(i - j < 0 ? 0 : i - j)] +
                input[(i + 1 + j >= length ? length - 1 : i + 1 + j)]) *
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               filter[j];
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      }
      sum >>= FILTER_BITS;
      *optr++ = clip_pixel(sum);
    }
  } else {
    // Initial part.
    for (i = 0; i < l1; i += 2) {
      int sum = (1 << (FILTER_BITS - 1));
      for (j = 0; j < filter_len_half; ++j) {
        sum += (input[(i - j < 0 ? 0 : i - j)] + input[i + 1 + j]) * filter[j];
      }
      sum >>= FILTER_BITS;
      *optr++ = clip_pixel(sum);
    }
    // Middle part.
    for (; i < l2; i += 2) {
      int sum = (1 << (FILTER_BITS - 1));
      for (j = 0; j < filter_len_half; ++j) {
        sum += (input[i - j] + input[i + 1 + j]) * filter[j];
      }
      sum >>= FILTER_BITS;
      *optr++ = clip_pixel(sum);
    }
    // End part.
    for (; i < length; i += 2) {
      int sum = (1 << (FILTER_BITS - 1));
      for (j = 0; j < filter_len_half; ++j) {
        sum += (input[i - j] +
                input[(i + 1 + j >= length ? length - 1 : i + 1 + j)]) *
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               filter[j];
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      }
      sum >>= FILTER_BITS;
      *optr++ = clip_pixel(sum);
    }
  }
}

static void down2_symodd(const uint8_t *const input, int length,
                         uint8_t *output) {
  // Actual filter len = 2 * filter_len_half - 1.
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  const int16_t *filter = vp9_down2_symodd_half_filter;
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  const int filter_len_half = sizeof(vp9_down2_symodd_half_filter) / 2;
  int i, j;
  uint8_t *optr = output;
  int l1 = filter_len_half - 1;
  int l2 = (length - filter_len_half + 1);
  l1 += (l1 & 1);
  l2 += (l2 & 1);
  if (l1 > l2) {
    // Short input length.
    for (i = 0; i < length; i += 2) {
      int sum = (1 << (FILTER_BITS - 1)) + input[i] * filter[0];
      for (j = 1; j < filter_len_half; ++j) {
        sum += (input[(i - j < 0 ? 0 : i - j)] +
                input[(i + j >= length ? length - 1 : i + j)]) *
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               filter[j];
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      }
      sum >>= FILTER_BITS;
      *optr++ = clip_pixel(sum);
    }
  } else {
    // Initial part.
    for (i = 0; i < l1; i += 2) {
      int sum = (1 << (FILTER_BITS - 1)) + input[i] * filter[0];
      for (j = 1; j < filter_len_half; ++j) {
        sum += (input[(i - j < 0 ? 0 : i - j)] + input[i + j]) * filter[j];
      }
      sum >>= FILTER_BITS;
      *optr++ = clip_pixel(sum);
    }
    // Middle part.
    for (; i < l2; i += 2) {
      int sum = (1 << (FILTER_BITS - 1)) + input[i] * filter[0];
      for (j = 1; j < filter_len_half; ++j) {
        sum += (input[i - j] + input[i + j]) * filter[j];
      }
      sum >>= FILTER_BITS;
      *optr++ = clip_pixel(sum);
    }
    // End part.
    for (; i < length; i += 2) {
      int sum = (1 << (FILTER_BITS - 1)) + input[i] * filter[0];
      for (j = 1; j < filter_len_half; ++j) {
        sum += (input[i - j] + input[(i + j >= length ? length - 1 : i + j)]) *
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               filter[j];
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      }
      sum >>= FILTER_BITS;
      *optr++ = clip_pixel(sum);
    }
  }
}

static int get_down2_length(int length, int steps) {
  int s;
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  for (s = 0; s < steps; ++s) length = (length + 1) >> 1;
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  return length;
}

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static int get_down2_steps(int in_length, int out_length) {
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  int steps = 0;
  int proj_in_length;
  while ((proj_in_length = get_down2_length(in_length, 1)) >= out_length) {
    ++steps;
    in_length = proj_in_length;
  }
  return steps;
}

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static void resize_multistep(const uint8_t *const input, int length,
                             uint8_t *output, int olength, uint8_t *otmp) {
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  int steps;
  if (length == olength) {
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    memcpy(output, input, sizeof(output[0]) * length);
372 373 374 375 376 377 378
    return;
  }
  steps = get_down2_steps(length, olength);

  if (steps > 0) {
    int s;
    uint8_t *out = NULL;
379
    uint8_t *otmp2;
380
    int filteredlength = length;
381 382

    assert(otmp != NULL);
383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422
    otmp2 = otmp + get_down2_length(length, 1);
    for (s = 0; s < steps; ++s) {
      const int proj_filteredlength = get_down2_length(filteredlength, 1);
      const uint8_t *const in = (s == 0 ? input : out);
      if (s == steps - 1 && proj_filteredlength == olength)
        out = output;
      else
        out = (s & 1 ? otmp2 : otmp);
      if (filteredlength & 1)
        down2_symodd(in, filteredlength, out);
      else
        down2_symeven(in, filteredlength, out);
      filteredlength = proj_filteredlength;
    }
    if (filteredlength != olength) {
      interpolate(out, filteredlength, output, olength);
    }
  } else {
    interpolate(input, length, output, olength);
  }
}

static void fill_col_to_arr(uint8_t *img, int stride, int len, uint8_t *arr) {
  int i;
  uint8_t *iptr = img;
  uint8_t *aptr = arr;
  for (i = 0; i < len; ++i, iptr += stride) {
    *aptr++ = *iptr;
  }
}

static void fill_arr_to_col(uint8_t *img, int stride, int len, uint8_t *arr) {
  int i;
  uint8_t *iptr = img;
  uint8_t *aptr = arr;
  for (i = 0; i < len; ++i, iptr += stride) {
    *iptr = *aptr++;
  }
}

423 424
void vp9_resize_plane(const uint8_t *const input, int height, int width,
                      int in_stride, uint8_t *output, int height2, int width2,
425 426 427
                      int out_stride) {
  int i;
  uint8_t *intbuf = (uint8_t *)malloc(sizeof(uint8_t) * width2 * height);
428 429
  uint8_t *tmpbuf =
      (uint8_t *)malloc(sizeof(uint8_t) * (width < height ? height : width));
430 431
  uint8_t *arrbuf = (uint8_t *)malloc(sizeof(uint8_t) * height);
  uint8_t *arrbuf2 = (uint8_t *)malloc(sizeof(uint8_t) * height2);
432
  if (intbuf == NULL || tmpbuf == NULL || arrbuf == NULL || arrbuf2 == NULL)
433
    goto Error;
434 435 436 437
  assert(width > 0);
  assert(height > 0);
  assert(width2 > 0);
  assert(height2 > 0);
438
  for (i = 0; i < height; ++i)
439 440
    resize_multistep(input + in_stride * i, width, intbuf + width2 * i, width2,
                     tmpbuf);
441 442
  for (i = 0; i < width2; ++i) {
    fill_col_to_arr(intbuf + i, width2, height, arrbuf);
443 444
    resize_multistep(arrbuf, height, arrbuf2, height2, tmpbuf);
    fill_arr_to_col(output + i, out_stride, height2, arrbuf2);
445
  }
446

447
Error:
448 449 450
  free(intbuf);
  free(tmpbuf);
  free(arrbuf);
451
  free(arrbuf2);
452 453
}

454 455 456 457 458
#if CONFIG_VP9_HIGHBITDEPTH
static void highbd_interpolate(const uint16_t *const input, int inlength,
                               uint16_t *output, int outlength, int bd) {
  const int64_t delta =
      (((uint64_t)inlength << 32) + outlength / 2) / outlength;
459 460 461 462 463 464
  const int64_t offset =
      inlength > outlength
          ? (((int64_t)(inlength - outlength) << 31) + outlength / 2) /
                outlength
          : -(((int64_t)(outlength - inlength) << 31) + outlength / 2) /
                outlength;
465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480
  uint16_t *optr = output;
  int x, x1, x2, sum, k, int_pel, sub_pel;
  int64_t y;

  const interp_kernel *interp_filters =
      choose_interp_filter(inlength, outlength);

  x = 0;
  y = offset;
  while ((y >> INTERP_PRECISION_BITS) < (INTERP_TAPS / 2 - 1)) {
    x++;
    y += delta;
  }
  x1 = x;
  x = outlength - 1;
  y = delta * x + offset;
481 482
  while ((y >> INTERP_PRECISION_BITS) + (int64_t)(INTERP_TAPS / 2) >=
         inlength) {
483 484 485 486 487 488 489 490 491 492 493 494 495 496
    x--;
    y -= delta;
  }
  x2 = x;
  if (x1 > x2) {
    for (x = 0, y = offset; x < outlength; ++x, y += delta) {
      const int16_t *filter;
      int_pel = y >> INTERP_PRECISION_BITS;
      sub_pel = (y >> (INTERP_PRECISION_BITS - SUBPEL_BITS)) & SUBPEL_MASK;
      filter = interp_filters[sub_pel];
      sum = 0;
      for (k = 0; k < INTERP_TAPS; ++k) {
        const int pk = int_pel - INTERP_TAPS / 2 + 1 + k;
        sum += filter[k] *
497
               input[(pk < 0 ? 0 : (pk >= inlength ? inlength - 1 : pk))];
498
      }
499
      *optr++ = clip_pixel_highbd(ROUND_POWER_OF_TWO(sum, FILTER_BITS), bd);
500 501 502 503 504 505 506 507 508 509
    }
  } else {
    // Initial part.
    for (x = 0, y = offset; x < x1; ++x, y += delta) {
      const int16_t *filter;
      int_pel = y >> INTERP_PRECISION_BITS;
      sub_pel = (y >> (INTERP_PRECISION_BITS - SUBPEL_BITS)) & SUBPEL_MASK;
      filter = interp_filters[sub_pel];
      sum = 0;
      for (k = 0; k < INTERP_TAPS; ++k)
510 511 512
        sum += filter[k] * input[(int_pel - INTERP_TAPS / 2 + 1 + k < 0
                                      ? 0
                                      : int_pel - INTERP_TAPS / 2 + 1 + k)];
513
      *optr++ = clip_pixel_highbd(ROUND_POWER_OF_TWO(sum, FILTER_BITS), bd);
514 515 516 517 518 519 520 521 522 523
    }
    // Middle part.
    for (; x <= x2; ++x, y += delta) {
      const int16_t *filter;
      int_pel = y >> INTERP_PRECISION_BITS;
      sub_pel = (y >> (INTERP_PRECISION_BITS - SUBPEL_BITS)) & SUBPEL_MASK;
      filter = interp_filters[sub_pel];
      sum = 0;
      for (k = 0; k < INTERP_TAPS; ++k)
        sum += filter[k] * input[int_pel - INTERP_TAPS / 2 + 1 + k];
524
      *optr++ = clip_pixel_highbd(ROUND_POWER_OF_TWO(sum, FILTER_BITS), bd);
525 526 527 528 529 530 531 532 533
    }
    // End part.
    for (; x < outlength; ++x, y += delta) {
      const int16_t *filter;
      int_pel = y >> INTERP_PRECISION_BITS;
      sub_pel = (y >> (INTERP_PRECISION_BITS - SUBPEL_BITS)) & SUBPEL_MASK;
      filter = interp_filters[sub_pel];
      sum = 0;
      for (k = 0; k < INTERP_TAPS; ++k)
534 535 536
        sum += filter[k] * input[(int_pel - INTERP_TAPS / 2 + 1 + k >= inlength
                                      ? inlength - 1
                                      : int_pel - INTERP_TAPS / 2 + 1 + k)];
537
      *optr++ = clip_pixel_highbd(ROUND_POWER_OF_TWO(sum, FILTER_BITS), bd);
538 539 540 541 542 543 544 545 546 547 548 549 550 551 552 553 554 555 556 557 558 559
    }
  }
}

static void highbd_down2_symeven(const uint16_t *const input, int length,
                                 uint16_t *output, int bd) {
  // Actual filter len = 2 * filter_len_half.
  static const int16_t *filter = vp9_down2_symeven_half_filter;
  const int filter_len_half = sizeof(vp9_down2_symeven_half_filter) / 2;
  int i, j;
  uint16_t *optr = output;
  int l1 = filter_len_half;
  int l2 = (length - filter_len_half);
  l1 += (l1 & 1);
  l2 += (l2 & 1);
  if (l1 > l2) {
    // Short input length.
    for (i = 0; i < length; i += 2) {
      int sum = (1 << (FILTER_BITS - 1));
      for (j = 0; j < filter_len_half; ++j) {
        sum += (input[(i - j < 0 ? 0 : i - j)] +
                input[(i + 1 + j >= length ? length - 1 : i + 1 + j)]) *
560
               filter[j];
561 562
      }
      sum >>= FILTER_BITS;
563
      *optr++ = clip_pixel_highbd(sum, bd);
564 565 566 567 568 569 570 571 572
    }
  } else {
    // Initial part.
    for (i = 0; i < l1; i += 2) {
      int sum = (1 << (FILTER_BITS - 1));
      for (j = 0; j < filter_len_half; ++j) {
        sum += (input[(i - j < 0 ? 0 : i - j)] + input[i + 1 + j]) * filter[j];
      }
      sum >>= FILTER_BITS;
573
      *optr++ = clip_pixel_highbd(sum, bd);
574 575 576 577 578 579 580 581
    }
    // Middle part.
    for (; i < l2; i += 2) {
      int sum = (1 << (FILTER_BITS - 1));
      for (j = 0; j < filter_len_half; ++j) {
        sum += (input[i - j] + input[i + 1 + j]) * filter[j];
      }
      sum >>= FILTER_BITS;
582
      *optr++ = clip_pixel_highbd(sum, bd);
583 584 585 586 587 588 589
    }
    // End part.
    for (; i < length; i += 2) {
      int sum = (1 << (FILTER_BITS - 1));
      for (j = 0; j < filter_len_half; ++j) {
        sum += (input[i - j] +
                input[(i + 1 + j >= length ? length - 1 : i + 1 + j)]) *
590
               filter[j];
591 592
      }
      sum >>= FILTER_BITS;
593
      *optr++ = clip_pixel_highbd(sum, bd);
594 595 596 597 598
    }
  }
}

static void highbd_down2_symodd(const uint16_t *const input, int length,
599
                                uint16_t *output, int bd) {
600 601 602 603 604 605 606 607 608 609 610 611 612 613 614 615
  // Actual filter len = 2 * filter_len_half - 1.
  static const int16_t *filter = vp9_down2_symodd_half_filter;
  const int filter_len_half = sizeof(vp9_down2_symodd_half_filter) / 2;
  int i, j;
  uint16_t *optr = output;
  int l1 = filter_len_half - 1;
  int l2 = (length - filter_len_half + 1);
  l1 += (l1 & 1);
  l2 += (l2 & 1);
  if (l1 > l2) {
    // Short input length.
    for (i = 0; i < length; i += 2) {
      int sum = (1 << (FILTER_BITS - 1)) + input[i] * filter[0];
      for (j = 1; j < filter_len_half; ++j) {
        sum += (input[(i - j < 0 ? 0 : i - j)] +
                input[(i + j >= length ? length - 1 : i + j)]) *
616
               filter[j];
617 618
      }
      sum >>= FILTER_BITS;
619
      *optr++ = clip_pixel_highbd(sum, bd);
620 621 622 623 624 625 626 627 628
    }
  } else {
    // Initial part.
    for (i = 0; i < l1; i += 2) {
      int sum = (1 << (FILTER_BITS - 1)) + input[i] * filter[0];
      for (j = 1; j < filter_len_half; ++j) {
        sum += (input[(i - j < 0 ? 0 : i - j)] + input[i + j]) * filter[j];
      }
      sum >>= FILTER_BITS;
629
      *optr++ = clip_pixel_highbd(sum, bd);
630 631 632 633 634 635 636 637
    }
    // Middle part.
    for (; i < l2; i += 2) {
      int sum = (1 << (FILTER_BITS - 1)) + input[i] * filter[0];
      for (j = 1; j < filter_len_half; ++j) {
        sum += (input[i - j] + input[i + j]) * filter[j];
      }
      sum >>= FILTER_BITS;
638
      *optr++ = clip_pixel_highbd(sum, bd);
639 640 641 642 643 644
    }
    // End part.
    for (; i < length; i += 2) {
      int sum = (1 << (FILTER_BITS - 1)) + input[i] * filter[0];
      for (j = 1; j < filter_len_half; ++j) {
        sum += (input[i - j] + input[(i + j >= length ? length - 1 : i + j)]) *
645
               filter[j];
646 647
      }
      sum >>= FILTER_BITS;
648
      *optr++ = clip_pixel_highbd(sum, bd);
649 650 651 652
    }
  }
}

653 654 655
static void highbd_resize_multistep(const uint16_t *const input, int length,
                                    uint16_t *output, int olength,
                                    uint16_t *otmp, int bd) {
656 657
  int steps;
  if (length == olength) {
658
    memcpy(output, input, sizeof(output[0]) * length);
659 660 661 662 663 664 665
    return;
  }
  steps = get_down2_steps(length, olength);

  if (steps > 0) {
    int s;
    uint16_t *out = NULL;
666
    uint16_t *otmp2;
667
    int filteredlength = length;
668 669

    assert(otmp != NULL);
670 671 672 673 674 675 676 677 678 679 680 681 682 683 684 685 686 687 688 689 690 691 692 693 694 695 696 697 698 699 700 701 702 703 704 705 706 707 708 709 710 711
    otmp2 = otmp + get_down2_length(length, 1);
    for (s = 0; s < steps; ++s) {
      const int proj_filteredlength = get_down2_length(filteredlength, 1);
      const uint16_t *const in = (s == 0 ? input : out);
      if (s == steps - 1 && proj_filteredlength == olength)
        out = output;
      else
        out = (s & 1 ? otmp2 : otmp);
      if (filteredlength & 1)
        highbd_down2_symodd(in, filteredlength, out, bd);
      else
        highbd_down2_symeven(in, filteredlength, out, bd);
      filteredlength = proj_filteredlength;
    }
    if (filteredlength != olength) {
      highbd_interpolate(out, filteredlength, output, olength, bd);
    }
  } else {
    highbd_interpolate(input, length, output, olength, bd);
  }
}

static void highbd_fill_col_to_arr(uint16_t *img, int stride, int len,
                                   uint16_t *arr) {
  int i;
  uint16_t *iptr = img;
  uint16_t *aptr = arr;
  for (i = 0; i < len; ++i, iptr += stride) {
    *aptr++ = *iptr;
  }
}

static void highbd_fill_arr_to_col(uint16_t *img, int stride, int len,
                                   uint16_t *arr) {
  int i;
  uint16_t *iptr = img;
  uint16_t *aptr = arr;
  for (i = 0; i < len; ++i, iptr += stride) {
    *iptr = *aptr++;
  }
}

712 713 714
void vp9_highbd_resize_plane(const uint8_t *const input, int height, int width,
                             int in_stride, uint8_t *output, int height2,
                             int width2, int out_stride, int bd) {
715 716
  int i;
  uint16_t *intbuf = (uint16_t *)malloc(sizeof(uint16_t) * width2 * height);
717 718
  uint16_t *tmpbuf =
      (uint16_t *)malloc(sizeof(uint16_t) * (width < height ? height : width));
719 720
  uint16_t *arrbuf = (uint16_t *)malloc(sizeof(uint16_t) * height);
  uint16_t *arrbuf2 = (uint16_t *)malloc(sizeof(uint16_t) * height2);
721
  if (intbuf == NULL || tmpbuf == NULL || arrbuf == NULL || arrbuf2 == NULL)
722
    goto Error;
723 724 725 726 727 728
  for (i = 0; i < height; ++i) {
    highbd_resize_multistep(CONVERT_TO_SHORTPTR(input + in_stride * i), width,
                            intbuf + width2 * i, width2, tmpbuf, bd);
  }
  for (i = 0; i < width2; ++i) {
    highbd_fill_col_to_arr(intbuf + i, width2, height, arrbuf);
729
    highbd_resize_multistep(arrbuf, height, arrbuf2, height2, tmpbuf, bd);
730
    highbd_fill_arr_to_col(CONVERT_TO_SHORTPTR(output + i), out_stride, height2,
731
                           arrbuf2);
732
  }
733

734
Error:
735 736 737
  free(intbuf);
  free(tmpbuf);
  free(arrbuf);
738
  free(arrbuf2);
739 740 741
}
#endif  // CONFIG_VP9_HIGHBITDEPTH

742
void vp9_resize_frame420(const uint8_t *const y, int y_stride,
743
                         const uint8_t *const u, const uint8_t *const v,
744 745 746 747 748 749 750 751
                         int uv_stride, int height, int width, uint8_t *oy,
                         int oy_stride, uint8_t *ou, uint8_t *ov,
                         int ouv_stride, int oheight, int owidth) {
  vp9_resize_plane(y, height, width, y_stride, oy, oheight, owidth, oy_stride);
  vp9_resize_plane(u, height / 2, width / 2, uv_stride, ou, oheight / 2,
                   owidth / 2, ouv_stride);
  vp9_resize_plane(v, height / 2, width / 2, uv_stride, ov, oheight / 2,
                   owidth / 2, ouv_stride);
752 753 754 755
}

void vp9_resize_frame422(const uint8_t *const y, int y_stride,
                         const uint8_t *const u, const uint8_t *const v,
756 757 758 759 760 761 762 763
                         int uv_stride, int height, int width, uint8_t *oy,
                         int oy_stride, uint8_t *ou, uint8_t *ov,
                         int ouv_stride, int oheight, int owidth) {
  vp9_resize_plane(y, height, width, y_stride, oy, oheight, owidth, oy_stride);
  vp9_resize_plane(u, height, width / 2, uv_stride, ou, oheight, owidth / 2,
                   ouv_stride);
  vp9_resize_plane(v, height, width / 2, uv_stride, ov, oheight, owidth / 2,
                   ouv_stride);
764 765 766 767
}

void vp9_resize_frame444(const uint8_t *const y, int y_stride,
                         const uint8_t *const u, const uint8_t *const v,
768 769 770 771 772 773 774 775
                         int uv_stride, int height, int width, uint8_t *oy,
                         int oy_stride, uint8_t *ou, uint8_t *ov,
                         int ouv_stride, int oheight, int owidth) {
  vp9_resize_plane(y, height, width, y_stride, oy, oheight, owidth, oy_stride);
  vp9_resize_plane(u, height, width, uv_stride, ou, oheight, owidth,
                   ouv_stride);
  vp9_resize_plane(v, height, width, uv_stride, ov, oheight, owidth,
                   ouv_stride);
776
}
777 778

#if CONFIG_VP9_HIGHBITDEPTH
779
void vp9_highbd_resize_frame420(const uint8_t *const y, int y_stride,
780
                                const uint8_t *const u, const uint8_t *const v,
781 782 783 784 785 786 787 788 789 790
                                int uv_stride, int height, int width,
                                uint8_t *oy, int oy_stride, uint8_t *ou,
                                uint8_t *ov, int ouv_stride, int oheight,
                                int owidth, int bd) {
  vp9_highbd_resize_plane(y, height, width, y_stride, oy, oheight, owidth,
                          oy_stride, bd);
  vp9_highbd_resize_plane(u, height / 2, width / 2, uv_stride, ou, oheight / 2,
                          owidth / 2, ouv_stride, bd);
  vp9_highbd_resize_plane(v, height / 2, width / 2, uv_stride, ov, oheight / 2,
                          owidth / 2, ouv_stride, bd);
791 792 793 794
}

void vp9_highbd_resize_frame422(const uint8_t *const y, int y_stride,
                                const uint8_t *const u, const uint8_t *const v,
795 796 797 798 799 800 801 802 803 804
                                int uv_stride, int height, int width,
                                uint8_t *oy, int oy_stride, uint8_t *ou,
                                uint8_t *ov, int ouv_stride, int oheight,
                                int owidth, int bd) {
  vp9_highbd_resize_plane(y, height, width, y_stride, oy, oheight, owidth,
                          oy_stride, bd);
  vp9_highbd_resize_plane(u, height, width / 2, uv_stride, ou, oheight,
                          owidth / 2, ouv_stride, bd);
  vp9_highbd_resize_plane(v, height, width / 2, uv_stride, ov, oheight,
                          owidth / 2, ouv_stride, bd);
805 806 807 808
}

void vp9_highbd_resize_frame444(const uint8_t *const y, int y_stride,
                                const uint8_t *const u, const uint8_t *const v,
809 810 811 812 813 814 815 816 817 818
                                int uv_stride, int height, int width,
                                uint8_t *oy, int oy_stride, uint8_t *ou,
                                uint8_t *ov, int ouv_stride, int oheight,
                                int owidth, int bd) {
  vp9_highbd_resize_plane(y, height, width, y_stride, oy, oheight, owidth,
                          oy_stride, bd);
  vp9_highbd_resize_plane(u, height, width, uv_stride, ou, oheight, owidth,
                          ouv_stride, bd);
  vp9_highbd_resize_plane(v, height, width, uv_stride, ov, oheight, owidth,
                          ouv_stride, bd);
819 820
}
#endif  // CONFIG_VP9_HIGHBITDEPTH