vp9_decodframe.c

/*
 *  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 "vp9/decoder/vp9_onyxd_int.h"
#include "vp9/common/vp9_common.h"
#include "vp9/common/vp9_header.h"
#include "vp9/common/vp9_reconintra.h"
#include "vp9/common/vp9_reconinter.h"
#include "vp9/common/vp9_entropy.h"
#include "vp9/decoder/vp9_decodframe.h"
#include "vp9/decoder/vp9_detokenize.h"
#include "vp9/common/vp9_invtrans.h"
#include "vp9/common/vp9_alloccommon.h"
#include "vp9/common/vp9_entropymode.h"
#include "vp9/common/vp9_quant_common.h"
#include "vpx_scale/vpx_scale.h"
#include "vp9/common/vp9_setupintrarecon.h"

#include "vp9/decoder/vp9_decodemv.h"
#include "vp9/common/vp9_extend.h"
#include "vp9/common/vp9_modecont.h"
#include "vpx_mem/vpx_mem.h"
#include "vp9/decoder/vp9_dboolhuff.h"

#include "vp9/common/vp9_seg_common.h"
#include "vp9/common/vp9_tile_common.h"
#include "vp9_rtcd.h"

#include <assert.h>
#include <stdio.h>

#define COEFCOUNT_TESTING

// #define DEC_DEBUG
#ifdef DEC_DEBUG
int dec_debug = 0;
#endif

static int read_le16(const uint8_t *p) {
  return (p[1] << 8) | p[0];
}

static int read_le32(const uint8_t *p) {
  return (p[3] << 24) | (p[2] << 16) | (p[1] << 8) | p[0];
}

// len == 0 is not allowed
static int read_is_valid(const unsigned char *start, size_t len,
                         const unsigned char *end) {
  return start + len > start && start + len <= end;
}

static int merge_index(int v, int n, int modulus) {
  int max1 = (n - 1 - modulus / 2) / modulus + 1;
  if (v < max1) v = v * modulus + modulus / 2;
  else {
    int w;
    v -= max1;
    w = v;
    v += (v + modulus - modulus / 2) / modulus;
    while (v % modulus == modulus / 2 ||
           w != v - (v + modulus - modulus / 2) / modulus) v++;
  }
  return v;
}

static int inv_remap_prob(int v, int m) {
  const int n = 256;
  const int modulus = MODULUS_PARAM;

  v = merge_index(v, n - 1, modulus);
  if ((m << 1) <= n) {
    return vp9_inv_recenter_nonneg(v + 1, m);
  } else {
    return n - 1 - vp9_inv_recenter_nonneg(v + 1, n - 1 - m);
  }
}

static vp9_prob read_prob_diff_update(vp9_reader *const bc, int oldp) {
  int delp = vp9_decode_term_subexp(bc, SUBEXP_PARAM, 255);
  return (vp9_prob)inv_remap_prob(delp, oldp);
}

void vp9_init_de_quantizer(VP9D_COMP *pbi) {
  int i;
  int q;
  VP9_COMMON *const pc = &pbi->common;

  for (q = 0; q < QINDEX_RANGE; q++) {
    pc->Y1dequant[q][0] = (int16_t)vp9_dc_quant(q, pc->y1dc_delta_q);
    pc->UVdequant[q][0] = (int16_t)vp9_dc_uv_quant(q, pc->uvdc_delta_q);

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

      pc->Y1dequant[q][rc] = (int16_t)vp9_ac_yquant(q);
      pc->UVdequant[q][rc] = (int16_t)vp9_ac_uv_quant(q, pc->uvac_delta_q);
    }
  }
}

static int get_qindex(MACROBLOCKD *mb, int segment_id, int base_qindex) {
  // Set the Q baseline allowing for any segment level adjustment
  if (vp9_segfeature_active(mb, segment_id, SEG_LVL_ALT_Q)) {
    if (mb->mb_segment_abs_delta == SEGMENT_ABSDATA)
      return vp9_get_segdata(mb, segment_id, SEG_LVL_ALT_Q);  // Abs Value
    else
      return clamp(base_qindex + vp9_get_segdata(mb, segment_id, SEG_LVL_ALT_Q),
                   0, MAXQ);  // Delta Value
  } else {
    return base_qindex;
  }
}

static void mb_init_dequantizer(VP9D_COMP *pbi, MACROBLOCKD *mb) {
  int i;

  VP9_COMMON *const pc = &pbi->common;
  const int segment_id = mb->mode_info_context->mbmi.segment_id;
  const int qindex = get_qindex(mb, segment_id, pc->base_qindex);
  mb->q_index = qindex;

  for (i = 0; i < 16; i++)
    mb->block[i].dequant = pc->Y1dequant[qindex];

  for (i = 16; i < 24; i++)
    mb->block[i].dequant = pc->UVdequant[qindex];

  if (mb->lossless) {
    assert(qindex == 0);
    mb->inv_txm4x4_1      = vp9_short_iwalsh4x4_1;
    mb->inv_txm4x4        = vp9_short_iwalsh4x4;
    mb->itxm_add          = vp9_dequant_idct_add_lossless_c;
    mb->itxm_add_y_block  = vp9_dequant_idct_add_y_block_lossless_c;
    mb->itxm_add_uv_block = vp9_dequant_idct_add_uv_block_lossless_c;
  } else {
    mb->inv_txm4x4_1      = vp9_short_idct4x4_1;
    mb->inv_txm4x4        = vp9_short_idct4x4;
    mb->itxm_add          = vp9_dequant_idct_add;
    mb->itxm_add_y_block  = vp9_dequant_idct_add_y_block;
    mb->itxm_add_uv_block = vp9_dequant_idct_add_uv_block;
  }
}

#if CONFIG_CODE_NONZEROCOUNT
static void propagate_nzcs(VP9_COMMON *cm, MACROBLOCKD *xd) {
  MODE_INFO *m = xd->mode_info_context;
  BLOCK_SIZE_TYPE sb_type = m->mbmi.sb_type;
  const int mis = cm->mode_info_stride;
  int n;
  if (sb_type == BLOCK_SIZE_SB64X64) {
    for (n = 0; n < 16; ++n) {
      int i = n >> 2;
      int j = n & 3;
      if (i == 0 && j == 0) continue;
      vpx_memcpy((m + j + mis * i)->mbmi.nzcs, m->mbmi.nzcs,
                 384 * sizeof(m->mbmi.nzcs[0]));
    }
  } else if (sb_type == BLOCK_SIZE_SB32X32) {
    for (n = 0; n < 4; ++n) {
      int i = n >> 1;
      int j = n & 1;
      if (i == 0 && j == 0) continue;
      vpx_memcpy((m + j + mis * i)->mbmi.nzcs, m->mbmi.nzcs,
                 384 * sizeof(m->mbmi.nzcs[0]));
    }
  }
}
#endif

/* skip_recon_mb() is Modified: Instead of writing the result to predictor buffer and then copying it
 *  to dst buffer, we can write the result directly to dst buffer. This eliminates unnecessary copy.
 */
static void skip_recon_mb(VP9D_COMP *pbi, MACROBLOCKD *xd,
                          int mb_row, int mb_col) {
  MODE_INFO *m = xd->mode_info_context;
  BLOCK_SIZE_TYPE sb_type = m->mbmi.sb_type;

  if (xd->mode_info_context->mbmi.ref_frame == INTRA_FRAME) {
    if (sb_type == BLOCK_SIZE_SB64X64) {
      vp9_build_intra_predictors_sb64uv_s(xd);
      vp9_build_intra_predictors_sb64y_s(xd);
    } else if (sb_type == BLOCK_SIZE_SB32X32) {
      vp9_build_intra_predictors_sbuv_s(xd);
      vp9_build_intra_predictors_sby_s(xd);
    } else {
      vp9_build_intra_predictors_mbuv_s(xd);
      vp9_build_intra_predictors_mby_s(xd);
    }
  } else {
    if (sb_type == BLOCK_SIZE_SB64X64) {