/*

 *  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 "./vpx_dsp_rtcd.h"

#include "vpx_config.h"

#include "vp8_rtcd.h"

#include "encodemb.h"

#include "vp8/common/reconinter.h"

#include "vp8/encoder/quantize.h"

#include "tokenize.h"

#include "vp8/common/invtrans.h"

#include "vpx_mem/vpx_mem.h"

#include "rdopt.h"

void vp8_subtract_b(BLOCK *be, BLOCKD *bd, int pitch) {

  unsigned char *src_ptr = (*(be->base_src) + be->src);

  short *diff_ptr = be->src_diff;

  unsigned char *pred_ptr = bd->predictor;

  int src_stride = be->src_stride;

  vpx_subtract_block(4, 4, diff_ptr, pitch, src_ptr, src_stride, pred_ptr,

                     pitch);

}

void vp8_subtract_mbuv(short *diff, unsigned char *usrc, unsigned char *vsrc,

                       int src_stride, unsigned char *upred,

                       unsigned char *vpred, int pred_stride) {

  short *udiff = diff + 256;

  short *vdiff = diff + 320;

  vpx_subtract_block(8, 8, udiff, 8, usrc, src_stride, upred, pred_stride);

  vpx_subtract_block(8, 8, vdiff, 8, vsrc, src_stride, vpred, pred_stride);

}

void vp8_subtract_mby(short *diff, unsigned char *src, int src_stride,

                      unsigned char *pred, int pred_stride) {

  vpx_subtract_block(16, 16, diff, 16, src, src_stride, pred, pred_stride);

}

static void vp8_subtract_mb(MACROBLOCK *x) {

  BLOCK *b = &x->block[0];

  vp8_subtract_mby(x->src_diff, *(b->base_src), b->src_stride,

                   x->e_mbd.dst.y_buffer, x->e_mbd.dst.y_stride);

  vp8_subtract_mbuv(x->src_diff, x->src.u_buffer, x->src.v_buffer,

                    x->src.uv_stride, x->e_mbd.dst.u_buffer,

                    x->e_mbd.dst.v_buffer, x->e_mbd.dst.uv_stride);

}

static void build_dcblock(MACROBLOCK *x) {

  short *src_diff_ptr = &x->src_diff[384];

  int i;

  for (i = 0; i < 16; ++i) {

    src_diff_ptr[i] = x->coeff[i * 16];

  }

}

void vp8_transform_mbuv(MACROBLOCK *x) {

  int i;

  for (i = 16; i < 24; i += 2) {

    x->short_fdct8x4(&x->block[i].src_diff[0], &x->block[i].coeff[0], 16);

  }

}

void vp8_transform_intra_mby(MACROBLOCK *x) {

  int i;

  for (i = 0; i < 16; i += 2) {

    x->short_fdct8x4(&x->block[i].src_diff[0], &x->block[i].coeff[0], 32);

  }

  /* build dc block from 16 y dc values */

  build_dcblock(x);

  /* do 2nd order transform on the dc block */

  x->short_walsh4x4(&x->block[24].src_diff[0], &x->block[24].coeff[0], 8);

}

static void transform_mb(MACROBLOCK *x) {

  int i;

  for (i = 0; i < 16; i += 2) {

    x->short_fdct8x4(&x->block[i].src_diff[0], &x->block[i].coeff[0], 32);

  }

  /* build dc block from 16 y dc values */

  if (x->e_mbd.mode_info_context->mbmi.mode != SPLITMV) build_dcblock(x);

  for (i = 16; i < 24; i += 2) {

    x->short_fdct8x4(&x->block[i].src_diff[0], &x->block[i].coeff[0], 16);

  }

  /* do 2nd order transform on the dc block */

  if (x->e_mbd.mode_info_context->mbmi.mode != SPLITMV) {

    x->short_walsh4x4(&x->block[24].src_diff[0], &x->block[24].coeff[0], 8);

  }

}

static void transform_mby(MACROBLOCK *x) {

  int i;

  for (i = 0; i < 16; i += 2) {

    x->short_fdct8x4(&x->block[i].src_diff[0], &x->block[i].coeff[0], 32);

  }

  /* build dc block from 16 y dc values */

  if (x->e_mbd.mode_info_context->mbmi.mode != SPLITMV) {

    build_dcblock(x);

    x->short_walsh4x4(&x->block[24].src_diff[0], &x->block[24].coeff[0], 8);

  }

}

#define RDTRUNC(RM, DM, R, D) ((128 + (R) * (RM)) & 0xFF)

typedef struct vp8_token_state vp8_token_state;

struct vp8_token_state {

  int rate;

  int error;

  signed char next;

  signed char token;

  short qc;

};

/* TODO: experiments to find optimal multiple numbers */

#define Y1_RD_MULT 4

#define UV_RD_MULT 2

#define Y2_RD_MULT 16

static const int plane_rd_mult[4] = { Y1_RD_MULT, Y2_RD_MULT, UV_RD_MULT,

                                      Y1_RD_MULT };

static void optimize_b(MACROBLOCK *mb, int ib, int type, ENTROPY_CONTEXT *a,

                       ENTROPY_CONTEXT *l) {

  BLOCK *b;

  BLOCKD *d;

  vp8_token_state tokens[17][2];

  unsigned best_mask[2];

  const short *dequant_ptr;

  const short *coeff_ptr;

  short *qcoeff_ptr;

  short *dqcoeff_ptr;

  int eob;

  int i0;

  int rc;

  int x;

  int sz = 0;

  int next;

  int rdmult;

  int rddiv;

  int final_eob;

  int rd_cost0;

  int rd_cost1;

  int rate0;

  int rate1;

  int error0;

  int error1;

  int t0;

  int t1;

  int best;

  int band;

  int pt;

  int i;

  int err_mult = plane_rd_mult[type];

  b = &mb->block[ib];

  d = &mb->e_mbd.block[ib];

  dequant_ptr = d->dequant;

  coeff_ptr = b->coeff;

  qcoeff_ptr = d->qcoeff;

  dqcoeff_ptr = d->dqcoeff;

  i0 = !type;

  eob = *d->eob;

  /* Now set up a Viterbi trellis to evaluate alternative roundings. */

  rdmult = mb->rdmult * err_mult;

  if (mb->e_mbd.mode_info_context->mbmi.ref_frame == INTRA_FRAME) {

    rdmult = (rdmult * 9) >> 4;

  }

  rddiv = mb->rddiv;

  best_mask[0] = best_mask[1] = 0;

  /* Initialize the sentinel node of the trellis. */

  tokens[eob][0].rate = 0;

  tokens[eob][0].error = 0;

  tokens[eob][0].next = 16;

  tokens[eob][0].token = DCT_EOB_TOKEN;

  tokens[eob][0].qc = 0;

  *(tokens[eob] + 1) = *(tokens[eob] + 0);

  next = eob;

  for (i = eob; i-- > i0;) {

    int base_bits;

    int d2;

    int dx;

    rc = vp8_default_zig_zag1d[i];

    x = qcoeff_ptr[rc];

    /* Only add a trellis state for non-zero coefficients. */

    if (x) {

      int shortcut = 0;

      error0 = tokens[next][0].error;

      error1 = tokens[next][1].error;

      /* Evaluate the first possibility for this state. */

      rate0 = tokens[next][0].rate;

      rate1 = tokens[next][1].rate;

      t0 = (vp8_dct_value_tokens_ptr + x)->Token;

      /* Consider both possible successor states. */

      if (next < 16) {

        band = vp8_coef_bands[i + 1];

        pt = vp8_prev_token_class[t0];

        rate0 += mb->token_costs[type][band][pt][tokens[next][0].token];

        rate1 += mb->token_costs[type][band][pt][tokens[next][1].token];

      }

      rd_cost0 = RDCOST(rdmult, rddiv, rate0, error0);

      rd_cost1 = RDCOST(rdmult, rddiv, rate1, error1);

      if (rd_cost0 == rd_cost1) {

        rd_cost0 = RDTRUNC(rdmult, rddiv, rate0, error0);

        rd_cost1 = RDTRUNC(rdmult, rddiv, rate1, error1);

      }

      /* And pick the best. */

      best = rd_cost1 < rd_cost0;

      base_bits = *(vp8_dct_value_cost_ptr + x);

      dx = dqcoeff_ptr[rc] - coeff_ptr[rc];

      d2 = dx * dx;

      tokens[i][0].rate = base_bits + (best ? rate1 : rate0);

      tokens[i][0].error = d2 + (best ? error1 : error0);

      tokens[i][0].next = next;

      tokens[i][0].token = t0;

      tokens[i][0].qc = x;

      best_mask[0] |= best << i;

      /* Evaluate the second possibility for this state. */

      rate0 = tokens[next][0].rate;

      rate1 = tokens[next][1].rate;

      if ((abs(x) * dequant_ptr[rc] > abs(coeff_ptr[rc])) &&

          (abs(x) * dequant_ptr[rc] < abs(coeff_ptr[rc]) + dequant_ptr[rc])) {

        shortcut = 1;

      } else {

        shortcut = 0;

      }

      if (shortcut) {

        sz = -(x < 0);

        x -= 2 * sz + 1;

      }

      /* Consider both possible successor states. */

      if (!x) {

        /* If we reduced this coefficient to zero, check to see if

         *  we need to move the EOB back here.

         */

        t0 =

            tokens[next][0].token == DCT_EOB_TOKEN ? DCT_EOB_TOKEN : ZERO_TOKEN;

        t1 =

            tokens[next][1].token == DCT_EOB_TOKEN ? DCT_EOB_TOKEN : ZERO_TOKEN;

      } else {

        t0 = t1 = (vp8_dct_value_tokens_ptr + x)->Token;

      }

      if (next < 16) {

        band = vp8_coef_bands[i + 1];

        if (t0 != DCT_EOB_TOKEN) {

          pt = vp8_prev_token_class[t0];

          rate0 += mb->token_costs[type][band][pt][tokens[next][0].token];

        }

        if (t1 != DCT_EOB_TOKEN) {

          pt = vp8_prev_token_class[t1];

          rate1 += mb->token_costs[type][band][pt][tokens[next][1].token];

        }

      }

      rd_cost0 = RDCOST(rdmult, rddiv, rate0, error0);

      rd_cost1 = RDCOST(rdmult, rddiv, rate1, error1);

      if (rd_cost0 == rd_cost1) {

        rd_cost0 = RDTRUNC(rdmult, rddiv, rate0, error0);

        rd_cost1 = RDTRUNC(rdmult, rddiv, rate1, error1);

      }

      /* And pick the best. */

      best = rd_cost1 < rd_cost0;

      base_bits = *(vp8_dct_value_cost_ptr + x);

      if (shortcut) {

        dx -= (dequant_ptr[rc] + sz) ^ sz;

        d2 = dx * dx;

      }

      tokens[i][1].rate = base_bits + (best ? rate1 : rate0);

      tokens[i][1].error = d2 + (best ? error1 : error0);

      tokens[i][1].next = next;

      tokens[i][1].token = best ? t1 : t0;

      tokens[i][1].qc = x;

      best_mask[1] |= best << i;

      /* Finally, make this the new head of the trellis. */

      next = i;

    }

    /* There's no choice to make for a zero coefficient, so we don't

     *  add a new trellis node, but we do need to update the costs.

     */

    else {

      band = vp8_coef_bands[i + 1];

      t0 = tokens[next][0].token;

      t1 = tokens[next][1].token;

      /* Update the cost of each path if we're past the EOB token. */

      if (t0 != DCT_EOB_TOKEN) {

        tokens[next][0].rate += mb->token_costs[type][band][0][t0];

        tokens[next][0].token = ZERO_TOKEN;

      }

      if (t1 != DCT_EOB_TOKEN) {

        tokens[next][1].rate += mb->token_costs[type][band][0][t1];

        tokens[next][1].token = ZERO_TOKEN;

      }

      /* Don't update next, because we didn't add a new node. */

    }

  }

  /* Now pick the best path through the whole trellis. */

  band = vp8_coef_bands[i + 1];

  VP8_COMBINEENTROPYCONTEXTS(pt, *a, *l);

  rate0 = tokens[next][0].rate;

  rate1 = tokens[next][1].rate;

  error0 = tokens[next][0].error;

  error1 = tokens[next][1].error;

  t0 = tokens[next][0].token;

  t1 = tokens[next][1].token;

  rate0 += mb->token_costs[type][band][pt][t0];

  rate1 += mb->token_costs[type][band][pt][t1];

  rd_cost0 = RDCOST(rdmult, rddiv, rate0, error0);

  rd_cost1 = RDCOST(rdmult, rddiv, rate1, error1);

  if (rd_cost0 == rd_cost1) {

    rd_cost0 = RDTRUNC(rdmult, rddiv, rate0, error0);

    rd_cost1 = RDTRUNC(rdmult, rddiv, rate1, error1);

  }

  best = rd_cost1 < rd_cost0;

  final_eob = i0 - 1;

  for (i = next; i < eob; i = next) {

    x = tokens[i][best].qc;

    if (x) final_eob = i;

    rc = vp8_default_zig_zag1d[i];

    qcoeff_ptr[rc] = x;

    dqcoeff_ptr[rc] = x * dequant_ptr[rc];

    next = tokens[i][best].next;

    best = (best_mask[best] >> i) & 1;

  }

  final_eob++;

  *a = *l = (final_eob != !type);

  *d->eob = (char)final_eob;

}

static void check_reset_2nd_coeffs(MACROBLOCKD *x, int type, ENTROPY_CONTEXT *a,

                                   ENTROPY_CONTEXT *l) {

  int sum = 0;

  int i;

  BLOCKD *bd = &x->block[24];

  if (bd->dequant[0] >= 35 && bd->dequant[1] >= 35) return;

  for (i = 0; i < (*bd->eob); ++i) {

    int coef = bd->dqcoeff[vp8_default_zig_zag1d[i]];

    sum += (coef >= 0) ? coef : -coef;

    if (sum >= 35) return;

  }

  /**************************************************************************

  our inverse hadamard transform effectively is weighted sum of all 16 inputs

  with weight either 1 or -1. It has a last stage scaling of (sum+3)>>3. And

  dc only idct is (dc+4)>>3. So if all the sums are between -35 and 29, the

  output after inverse wht and idct will be all zero. A sum of absolute value

  smaller than 35 guarantees all 16 different (+1/-1) weighted sums in wht

  fall between -35 and +35.

  **************************************************************************/

  if (sum < 35) {

    for (i = 0; i < (*bd->eob); ++i) {

      int rc = vp8_default_zig_zag1d[i];

      bd->qcoeff[rc] = 0;

      bd->dqcoeff[rc] = 0;

    }

    *bd->eob = 0;

    *a = *l = (*bd->eob != !type);

  }

}

static void optimize_mb(MACROBLOCK *x) {

  int b;

  int type;

  int has_2nd_order;

  ENTROPY_CONTEXT_PLANES t_above, t_left;

  ENTROPY_CONTEXT *ta;

  ENTROPY_CONTEXT *tl;

  t_above = *x->e_mbd.above_context;

  t_left = *x->e_mbd.left_context;

  ta = (ENTROPY_CONTEXT *)&t_above;

  tl = (ENTROPY_CONTEXT *)&t_left;

  has_2nd_order = (x->e_mbd.mode_info_context->mbmi.mode != B_PRED &&

                   x->e_mbd.mode_info_context->mbmi.mode != SPLITMV);

  type = has_2nd_order ? PLANE_TYPE_Y_NO_DC : PLANE_TYPE_Y_WITH_DC;

  for (b = 0; b < 16; ++b) {

    optimize_b(x, b, type, ta + vp8_block2above[b], tl + vp8_block2left[b]);

  }

  for (b = 16; b < 24; ++b) {

    optimize_b(x, b, PLANE_TYPE_UV, ta + vp8_block2above[b],

               tl + vp8_block2left[b]);

  }

  if (has_2nd_order) {

    b = 24;

    optimize_b(x, b, PLANE_TYPE_Y2, ta + vp8_block2above[b],

               tl + vp8_block2left[b]);

    check_reset_2nd_coeffs(&x->e_mbd, PLANE_TYPE_Y2, ta + vp8_block2above[b],

                           tl + vp8_block2left[b]);

  }

}

void vp8_optimize_mby(MACROBLOCK *x) {

  int b;

  int type;

  int has_2nd_order;

  ENTROPY_CONTEXT_PLANES t_above, t_left;

  ENTROPY_CONTEXT *ta;

  ENTROPY_CONTEXT *tl;

  if (!x->e_mbd.above_context) return;

  if (!x->e_mbd.left_context) return;

  t_above = *x->e_mbd.above_context;

  t_left = *x->e_mbd.left_context;

  ta = (ENTROPY_CONTEXT *)&t_above;

  tl = (ENTROPY_CONTEXT *)&t_left;

  has_2nd_order = (x->e_mbd.mode_info_context->mbmi.mode != B_PRED &&

                   x->e_mbd.mode_info_context->mbmi.mode != SPLITMV);

  type = has_2nd_order ? PLANE_TYPE_Y_NO_DC : PLANE_TYPE_Y_WITH_DC;

  for (b = 0; b < 16; ++b) {

    optimize_b(x, b, type, ta + vp8_block2above[b], tl + vp8_block2left[b]);

  }

  if (has_2nd_order) {

    b = 24;

    optimize_b(x, b, PLANE_TYPE_Y2, ta + vp8_block2above[b],

               tl + vp8_block2left[b]);

    check_reset_2nd_coeffs(&x->e_mbd, PLANE_TYPE_Y2, ta + vp8_block2above[b],

                           tl + vp8_block2left[b]);

  }

}

void vp8_optimize_mbuv(MACROBLOCK *x) {

  int b;

  ENTROPY_CONTEXT_PLANES t_above, t_left;

  ENTROPY_CONTEXT *ta;

  ENTROPY_CONTEXT *tl;

  if (!x->e_mbd.above_context) return;

  if (!x->e_mbd.left_context) return;

  t_above = *x->e_mbd.above_context;

  t_left = *x->e_mbd.left_context;

  ta = (ENTROPY_CONTEXT *)&t_above;

  tl = (ENTROPY_CONTEXT *)&t_left;

  for (b = 16; b < 24; ++b) {

    optimize_b(x, b, PLANE_TYPE_UV, ta + vp8_block2above[b],

               tl + vp8_block2left[b]);

  }

}

void vp8_encode_inter16x16(MACROBLOCK *x) {

  vp8_build_inter_predictors_mb(&x->e_mbd);

  vp8_subtract_mb(x);

  transform_mb(x);

  vp8_quantize_mb(x);

  if (x->optimize) optimize_mb(x);

}

/* this funciton is used by first pass only */

void vp8_encode_inter16x16y(MACROBLOCK *x) {

  BLOCK *b = &x->block[0];

  vp8_build_inter16x16_predictors_mby(&x->e_mbd, x->e_mbd.dst.y_buffer,

                                      x->e_mbd.dst.y_stride);

  vp8_subtract_mby(x->src_diff, *(b->base_src), b->src_stride,

                   x->e_mbd.dst.y_buffer, x->e_mbd.dst.y_stride);

  transform_mby(x);

  vp8_quantize_mby(x);

  vp8_inverse_transform_mby(&x->e_mbd);

}