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path: root/vp9/encoder/vp9_quantize.c
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/*
 *  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 <math.h>
#include "vpx_mem/vpx_mem.h"

#include "vp9/encoder/vp9_onyx_int.h"
#include "vp9/encoder/vp9_quantize.h"
#include "vp9/common/vp9_quant_common.h"

#include "vp9/common/vp9_seg_common.h"

#ifdef ENC_DEBUG
extern int enc_debug;
#endif

void vp9_ht_quantize_b_4x4(MACROBLOCK *mb, int b_idx, TX_TYPE tx_type) {
  MACROBLOCKD *const xd = &mb->e_mbd;
  BLOCK *const b = &mb->block[b_idx];
  BLOCKD *const d = &xd->block[b_idx];
  int i, rc, eob;
  int zbin;
  int x, y, z, sz;
  int16_t *zbin_boost_ptr  = b->zrun_zbin_boost;
  int16_t *coeff_ptr       = b->coeff;
  int16_t *zbin_ptr        = b->zbin;
  int16_t *round_ptr       = b->round;
  int16_t *quant_ptr       = b->quant;
  uint8_t *quant_shift_ptr = b->quant_shift;
  int16_t *qcoeff_ptr      = d->qcoeff;
  int16_t *dqcoeff_ptr     = d->dqcoeff;
  int16_t *dequant_ptr     = d->dequant;
  int zbin_oq_value        = b->zbin_extra;

  int const *pt_scan ;

  switch (tx_type) {
    case ADST_DCT:
      pt_scan = vp9_row_scan_4x4;
      break;

    case DCT_ADST:
      pt_scan = vp9_col_scan_4x4;
      break;

    default:
      pt_scan = vp9_default_zig_zag1d_4x4;
      break;
  }

  vpx_memset(qcoeff_ptr, 0, 32);
  vpx_memset(dqcoeff_ptr, 0, 32);

  eob = -1;

  if (!b->skip_block) {
    for (i = 0; i < 16; i++) {
      rc   = pt_scan[i];
      z    = coeff_ptr[rc];

      zbin = zbin_ptr[rc] + *zbin_boost_ptr + zbin_oq_value;
      zbin_boost_ptr++;

      sz = (z >> 31);                                 // sign of z
      x  = (z ^ sz) - sz;                             // x = abs(z)

      if (x >= zbin) {
        x += round_ptr[rc];
        y  = (((x * quant_ptr[rc]) >> 16) + x)
             >> quant_shift_ptr[rc];                // quantize (x)
        x  = (y ^ sz) - sz;                         // get the sign back
        qcoeff_ptr[rc]  = x;                        // write to destination
        dqcoeff_ptr[rc] = x * dequant_ptr[rc];      // dequantized value

        if (y) {
          eob = i;                                // last nonzero coeffs
          zbin_boost_ptr = b->zrun_zbin_boost;    // reset zero runlength
        }
      }
    }
  }

  xd->eobs[b_idx] = eob + 1;
}

void vp9_regular_quantize_b_4x4(MACROBLOCK *mb, int b_idx) {
  MACROBLOCKD *const xd = &mb->e_mbd;
  BLOCK *const b = &mb->block[b_idx];
  BLOCKD *const d = &xd->block[b_idx];
  int i, rc, eob;
  int zbin;
  int x, y, z, sz;
  int16_t *zbin_boost_ptr  = b->zrun_zbin_boost;
  int16_t *coeff_ptr       = b->coeff;
  int16_t *zbin_ptr        = b->zbin;
  int16_t *round_ptr       = b->round;
  int16_t *quant_ptr       = b->quant;
  uint8_t *quant_shift_ptr = b->quant_shift;
  int16_t *qcoeff_ptr      = d->qcoeff;
  int16_t *dqcoeff_ptr     = d->dqcoeff;
  int16_t *dequant_ptr     = d->dequant;
  int zbin_oq_value        = b->zbin_extra;

  vpx_memset(qcoeff_ptr, 0, 32);
  vpx_memset(dqcoeff_ptr, 0, 32);

  eob = -1;

  if (!b->skip_block) {
    for (i = 0; i < 16; i++) {
      rc   = vp9_default_zig_zag1d_4x4[i];
      z    = coeff_ptr[rc];

      zbin = zbin_ptr[rc] + *zbin_boost_ptr + zbin_oq_value;
      zbin_boost_ptr++;

      sz = (z >> 31);                                 // sign of z
      x  = (z ^ sz) - sz;                             // x = abs(z)

      if (x >= zbin) {
        x += round_ptr[rc];

        y  = (((x * quant_ptr[rc]) >> 16) + x)
             >> quant_shift_ptr[rc];                // quantize (x)
        x  = (y ^ sz) - sz;                         // get the sign back
        qcoeff_ptr[rc]  = x;                        // write to destination
        dqcoeff_ptr[rc] = x * dequant_ptr[rc];      // dequantized value

        if (y) {
          eob = i;                                // last nonzero coeffs
          zbin_boost_ptr = b->zrun_zbin_boost;    // reset zero runlength
        }
      }
    }
  }

  xd->eobs[b_idx] = eob + 1;
}

void vp9_quantize_mby_4x4_c(MACROBLOCK *x) {
  int i;

  for (i = 0; i < 16; i++) {
    TX_TYPE tx_type = get_tx_type_4x4(&x->e_mbd, &x->e_mbd.block[i]);
    if (tx_type != DCT_DCT) {
      vp9_ht_quantize_b_4x4(x, i, tx_type);
    } else {
      x->quantize_b_4x4(x, i);
    }
  }
}

void vp9_quantize_mbuv_4x4_c(MACROBLOCK *x) {
  int i;

  for (i = 16; i < 24; i++)
    x->quantize_b_4x4(x, i);
}

void vp9_quantize_mb_4x4_c(MACROBLOCK *x) {
  vp9_quantize_mby_4x4_c(x);
  vp9_quantize_mbuv_4x4_c(x);
}

void vp9_regular_quantize_b_8x8(MACROBLOCK *mb, int b_idx) {
  MACROBLOCKD *const xd = &mb->e_mbd;
  BLOCK *const b = &mb->block[b_idx];
  BLOCKD *const d = &xd->block[b_idx];
  int16_t *qcoeff_ptr = d->qcoeff;
  int16_t *dqcoeff_ptr = d->dqcoeff;

  vpx_memset(qcoeff_ptr, 0, 64 * sizeof(int16_t));
  vpx_memset(dqcoeff_ptr, 0, 64 * sizeof(int16_t));

  if (!b->skip_block) {
    int i, rc, eob;
    int zbin;
    int x, y, z, sz;
    int zero_run;
    int16_t *zbin_boost_ptr = b->zrun_zbin_boost;
    int16_t *coeff_ptr  = b->coeff;
    int16_t *zbin_ptr   = b->zbin;
    int16_t *round_ptr  = b->round;
    int16_t *quant_ptr  = b->quant;
    uint8_t *quant_shift_ptr = b->quant_shift;
    int16_t *dequant_ptr = d->dequant;
    int zbin_oq_value = b->zbin_extra;

    eob = -1;

    // Special case for DC as it is the one triggering access in various
    // tables: {zbin, quant, quant_shift, dequant}_ptr[rc != 0]
    {
      z    = coeff_ptr[0];
      zbin = (zbin_ptr[0] + zbin_boost_ptr[0] + zbin_oq_value);
      zero_run = 1;

      sz = (z >> 31);                                // sign of z
      x  = (z ^ sz) - sz;                            // x = abs(z)

      if (x >= zbin) {
        x += (round_ptr[0]);
        y  = ((int)(((int)(x * quant_ptr[0]) >> 16) + x))
             >> quant_shift_ptr[0];                  // quantize (x)
        x  = (y ^ sz) - sz;                          // get the sign back
        qcoeff_ptr[0]  = x;                          // write to destination
        dqcoeff_ptr[0] = x * dequant_ptr[0];         // dequantized value

        if (y) {
          eob = 0;                                   // last nonzero coeffs
          zero_run = 0;
        }
      }
    }
    for (i = 1; i < 64; i++) {
      rc   = vp9_default_zig_zag1d_8x8[i];
      z    = coeff_ptr[rc];
      zbin = (zbin_ptr[1] + zbin_boost_ptr[zero_run] + zbin_oq_value);
      // The original code was incrementing zero_run while keeping it at
      // maximum 15 by adding "(zero_run < 15)". The same is achieved by
      // removing the opposite of the sign mask of "(zero_run - 15)".
      zero_run -= (zero_run - 15) >> 31;

      sz = (z >> 31);                                // sign of z
      x  = (z ^ sz) - sz;                            // x = abs(z)

      if (x >= zbin) {
        x += (round_ptr[rc != 0]);
        y  = ((int)(((int)(x * quant_ptr[1]) >> 16) + x))
             >> quant_shift_ptr[1];                  // quantize (x)
        x  = (y ^ sz) - sz;                          // get the sign back
        qcoeff_ptr[rc]  = x;                         // write to destination
        dqcoeff_ptr[rc] = x * dequant_ptr[1];        // dequantized value

        if (y) {
          eob = i;                                   // last nonzero coeffs
          zero_run = 0;
        }
      }
    }
    xd->eobs[b_idx] = eob + 1;
  } else {
    xd->eobs[b_idx] = 0;
  }
}

void vp9_quantize_mby_8x8(MACROBLOCK *x) {
  int i;

  for (i = 0; i < 16; i += 4) {
    x->quantize_b_8x8(x, i);
  }
}

void vp9_quantize_mbuv_8x8(MACROBLOCK *x) {
  int i;

  for (i = 16; i < 24; i += 4)
    x->quantize_b_8x8(x, i);
}

void vp9_quantize_mb_8x8(MACROBLOCK *x) {
  vp9_quantize_mby_8x8(x);
  vp9_quantize_mbuv_8x8(x);
}

void vp9_quantize_mby_16x16(MACROBLOCK *x) {
  x->quantize_b_16x16(x, 0);
}

void vp9_quantize_mb_16x16(MACROBLOCK *x) {
  vp9_quantize_mby_16x16(x);
  vp9_quantize_mbuv_8x8(x);
}

static void quantize(int16_t *zbin_boost_orig_ptr,
                     int16_t *coeff_ptr, int n_coeffs, int skip_block,
                     int16_t *zbin_ptr, int16_t *round_ptr, int16_t *quant_ptr,
                     uint8_t *quant_shift_ptr,
                     int16_t *qcoeff_ptr, int16_t *dqcoeff_ptr,
                     int16_t *dequant_ptr, int zbin_oq_value,
                     uint16_t *eob_ptr, const int *scan, int mul) {
  int i, rc, eob;
  int zbin;
  int x, y, z, sz;
  int zero_run = 0;
  int16_t *zbin_boost_ptr = zbin_boost_orig_ptr;

  vpx_memset(qcoeff_ptr, 0, n_coeffs*sizeof(int16_t));
  vpx_memset(dqcoeff_ptr, 0, n_coeffs*sizeof(int16_t));

  eob = -1;

  if (!skip_block) {
    for (i = 0; i < n_coeffs; i++) {
      rc   = scan[i];
      z    = coeff_ptr[rc] * mul;

      zbin = (zbin_ptr[rc != 0] + zbin_boost_ptr[zero_run] + zbin_oq_value);
      zero_run += (zero_run < 15);

      sz = (z >> 31);                               // sign of z
      x  = (z ^ sz) - sz;                           // x = abs(z)

      if (x >= zbin) {
        x += (round_ptr[rc != 0]);
        y  = ((int)(((int)(x * quant_ptr[rc != 0]) >> 16) + x))
            >> quant_shift_ptr[rc != 0];            // quantize (x)
        x  = (y ^ sz) - sz;                         // get the sign back
        qcoeff_ptr[rc]  = x;                        // write to destination
        dqcoeff_ptr[rc] = x * dequant_ptr[rc != 0] / mul;  // dequantized value

        if (y) {
          eob = i;                                  // last nonzero coeffs
          zero_run = 0;
        }
      }
    }
  }

  *eob_ptr = eob + 1;
}

void vp9_regular_quantize_b_16x16(MACROBLOCK *mb, int b_idx) {
  MACROBLOCKD *const xd = &mb->e_mbd;
  BLOCK *const b = &mb->block[b_idx];
  BLOCKD *const d = &xd->block[b_idx];
  quantize(b->zrun_zbin_boost,
           b->coeff,
           256, b->skip_block,
           b->zbin, b->round, b->quant, b->quant_shift,
           d->qcoeff,
           d->dqcoeff,
           d->dequant,
           b->zbin_extra,
           &xd->eobs[b_idx], vp9_default_zig_zag1d_16x16, 1);
}

void vp9_quantize_sby_32x32(MACROBLOCK *x) {
  MACROBLOCKD *xd = &x->e_mbd;
  BLOCK *b = &x->block[0];
  BLOCKD *d = &xd->block[0];

  quantize(b->zrun_zbin_boost,
           x->sb_coeff_data.coeff,
           1024, b->skip_block,
           b->zbin,
           b->round, b->quant, b->quant_shift,
           xd->sb_coeff_data.qcoeff,
           xd->sb_coeff_data.dqcoeff,
           d->dequant,
           b->zbin_extra,
           &xd->eobs[0],
           vp9_default_zig_zag1d_32x32, 2);
}

void vp9_quantize_sbuv_16x16(MACROBLOCK *x) {
  int i;
  MACROBLOCKD *xd = &x->e_mbd;

  for (i = 16; i < 24; i += 4)
    quantize(x->block[i].zrun_zbin_boost,
             x->sb_coeff_data.coeff + 1024 + (i - 16) * 64,
             256, x->block[i].skip_block,
             x->block[i].zbin,
             x->block[i].round, x->block[0].quant, x->block[i].quant_shift,
             xd->sb_coeff_data.qcoeff + 1024 + (i - 16) * 64,
             xd->sb_coeff_data.dqcoeff + 1024 + (i - 16) * 64,
             xd->block[i].dequant,
             x->block[i].zbin_extra,
             &xd->eobs[i],
             vp9_default_zig_zag1d_16x16, 1);
}

/* quantize_b_pair function pointer in MACROBLOCK structure is set to one of
 * these two C functions if corresponding optimized routine is not available.
 * NEON optimized version implements currently the fast quantization for pair
 * of blocks. */
void vp9_regular_quantize_b_4x4_pair(MACROBLOCK *x, int b_idx1, int b_idx2) {
  vp9_regular_quantize_b_4x4(x, b_idx1);
  vp9_regular_quantize_b_4x4(x, b_idx2);
}

static void invert_quant(int16_t *quant,
                         uint8_t *shift, int d) {
  unsigned t;
  int l;
  t = d;
  for (l = 0; t > 1; l++)
    t >>= 1;
  t = 1 + (1 << (16 + l)) / d;
  *quant = (int16_t)(t - (1 << 16));
  *shift = l;
}

void vp9_init_quantizer(VP9_COMP *cpi) {
  int i;
  int quant_val;
  int Q;

  static const int zbin_boost[16] = { 0,  0,  0,  8,  8,  8, 10, 12,
                                     14, 16, 20, 24, 28, 32, 36, 40 };

  for (Q = 0; Q < QINDEX_RANGE; Q++) {
    int qzbin_factor = (vp9_dc_quant(Q, 0) < 148) ? 84 : 80;
    int qrounding_factor = 48;
    if (Q == 0) {
      qzbin_factor = 64;
      qrounding_factor = 64;
    }
    // dc values
    quant_val = vp9_dc_quant(Q, cpi->common.y1dc_delta_q);
    invert_quant(cpi->Y1quant[Q] + 0,
                 cpi->Y1quant_shift[Q] + 0, quant_val);
    cpi->Y1zbin[Q][0] = ((qzbin_factor * quant_val) + 64) >> 7;
    cpi->Y1round[Q][0] = (qrounding_factor * quant_val) >> 7;
    cpi->common.Y1dequant[Q][0] = quant_val;
    cpi->zrun_zbin_boost_y1[Q][0] = (quant_val * zbin_boost[0]) >> 7;

    quant_val = vp9_dc_uv_quant(Q, cpi->common.uvdc_delta_q);
    invert_quant(cpi->UVquant[Q] + 0,
                 cpi->UVquant_shift[Q] + 0, quant_val);
    cpi->UVzbin[Q][0] = ((qzbin_factor * quant_val) + 64) >> 7;
    cpi->UVround[Q][0] = (qrounding_factor * quant_val) >> 7;
    cpi->common.UVdequant[Q][0] = quant_val;
    cpi->zrun_zbin_boost_uv[Q][0] = (quant_val * zbin_boost[0]) >> 7;

    // all the 4x4 ac values =;
    for (i = 1; i < 16; i++) {
      int rc = vp9_default_zig_zag1d_4x4[i];

      quant_val = vp9_ac_yquant(Q);
      invert_quant(cpi->Y1quant[Q] + rc,
                   cpi->Y1quant_shift[Q] + rc, quant_val);
      cpi->Y1zbin[Q][rc] = ((qzbin_factor * quant_val) + 64) >> 7;
      cpi->Y1round[Q][rc] = (qrounding_factor * quant_val) >> 7;
      cpi->common.Y1dequant[Q][rc] = quant_val;
      cpi->zrun_zbin_boost_y1[Q][i] =
        ((quant_val * zbin_boost[i]) + 64) >> 7;

      quant_val = vp9_ac_uv_quant(Q, cpi->common.uvac_delta_q);
      invert_quant(cpi->UVquant[Q] + rc,
                   cpi->UVquant_shift[Q] + rc, quant_val);
      cpi->UVzbin[Q][rc] = ((qzbin_factor * quant_val) + 64) >> 7;
      cpi->UVround[Q][rc] = (qrounding_factor * quant_val) >> 7;
      cpi->common.UVdequant[Q][rc] = quant_val;
      cpi->zrun_zbin_boost_uv[Q][i] =
        ((quant_val * zbin_boost[i]) + 64) >> 7;
    }
  }
}

void vp9_mb_init_quantizer(VP9_COMP *cpi, MACROBLOCK *x) {
  int i;
  int QIndex;
  MACROBLOCKD *xd = &x->e_mbd;
  int zbin_extra;
  int segment_id = xd->mode_info_context->mbmi.segment_id;

  // Select the baseline MB Q index allowing for any segment level change.
  if (vp9_segfeature_active(xd, segment_id, SEG_LVL_ALT_Q)) {
    // Abs Value
    if (xd->mb_segment_abs_delta == SEGMENT_ABSDATA)
      QIndex = vp9_get_segdata(xd, segment_id, SEG_LVL_ALT_Q);

    // Delta Value
    else {
      QIndex = cpi->common.base_qindex +
               vp9_get_segdata(xd, segment_id, SEG_LVL_ALT_Q);

      // Clamp to valid range
      QIndex = (QIndex >= 0) ? ((QIndex <= MAXQ) ? QIndex : MAXQ) : 0;
    }
  } else
    QIndex = cpi->common.base_qindex;

  // Y
  zbin_extra = (cpi->common.Y1dequant[QIndex][1] *
                (cpi->zbin_mode_boost +
                 x->act_zbin_adj)) >> 7;

  for (i = 0; i < 16; i++) {
    x->block[i].quant = cpi->Y1quant[QIndex];
    x->block[i].quant_shift = cpi->Y1quant_shift[QIndex];
    x->block[i].zbin = cpi->Y1zbin[QIndex];
    x->block[i].round = cpi->Y1round[QIndex];
    x->e_mbd.block[i].dequant = cpi->common.Y1dequant[QIndex];
    x->block[i].zrun_zbin_boost = cpi->zrun_zbin_boost_y1[QIndex];
    x->block[i].zbin_extra = (int16_t)zbin_extra;

    // Segment skip feature.
    x->block[i].skip_block =
      vp9_segfeature_active(xd, segment_id, SEG_LVL_SKIP);
  }

  // UV
  zbin_extra = (cpi->common.UVdequant[QIndex][1] *
                (cpi->zbin_mode_boost +
                 x->act_zbin_adj)) >> 7;

  for (i = 16; i < 24; i++) {
    x->block[i].quant = cpi->UVquant[QIndex];
    x->block[i].quant_shift = cpi->UVquant_shift[QIndex];
    x->block[i].zbin = cpi->UVzbin[QIndex];
    x->block[i].round = cpi->UVround[QIndex];
    x->e_mbd.block[i].dequant = cpi->common.UVdequant[QIndex];
    x->block[i].zrun_zbin_boost = cpi->zrun_zbin_boost_uv[QIndex];
    x->block[i].zbin_extra = (int16_t)zbin_extra;

    // Segment skip feature.
    x->block[i].skip_block =
      vp9_segfeature_active(xd, segment_id, SEG_LVL_SKIP);
  }

  /* save this macroblock QIndex for vp9_update_zbin_extra() */
  x->e_mbd.q_index = QIndex;
}

void vp9_update_zbin_extra(VP9_COMP *cpi, MACROBLOCK *x) {
  int i;
  int QIndex = x->e_mbd.q_index;
  int zbin_extra;

  // Y
  zbin_extra = (cpi->common.Y1dequant[QIndex][1] *
                (cpi->zbin_mode_boost +
                 x->act_zbin_adj)) >> 7;
  for (i = 0; i < 16; i++) {
    x->block[i].zbin_extra = (int16_t)zbin_extra;
  }

  // UV
  zbin_extra = (cpi->common.UVdequant[QIndex][1] *
                (cpi->zbin_mode_boost +
                 x->act_zbin_adj)) >> 7;

  for (i = 16; i < 24; i++) {
    x->block[i].zbin_extra = (int16_t)zbin_extra;
  }
}

void vp9_frame_init_quantizer(VP9_COMP *cpi) {
  // Clear Zbin mode boost for default case
  cpi->zbin_mode_boost = 0;

  // MB level quantizer setup
  vp9_mb_init_quantizer(cpi, &cpi->mb);
}

void vp9_set_quantizer(struct VP9_COMP *cpi, int Q) {
  VP9_COMMON *cm = &cpi->common;

  cm->base_qindex = Q;

  // if any of the delta_q values are changing update flag will
  // have to be set.
  cm->y1dc_delta_q = 0;
  cm->uvdc_delta_q = 0;
  cm->uvac_delta_q = 0;

  // quantizer has to be reinitialized if any delta_q changes.
  // As there are not any here for now this is inactive code.
  // if(update)
  //    vp9_init_quantizer(cpi);
}