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 <assert.h>

#include "./vp9_rtcd.h"
#include "vpx_mem/vpx_mem.h"
#include "vpx_scale/vpx_scale.h"

#include "vp9/common/vp9_alloccommon.h"
#include "vp9/common/vp9_common.h"
#include "vp9/common/vp9_entropy.h"
#include "vp9/common/vp9_entropymode.h"
#include "vp9/common/vp9_extend.h"
#include "vp9/common/vp9_idct.h"
#include "vp9/common/vp9_pred_common.h"
#include "vp9/common/vp9_quant_common.h"
#include "vp9/common/vp9_reconintra.h"
#include "vp9/common/vp9_reconinter.h"
#include "vp9/common/vp9_seg_common.h"
#include "vp9/common/vp9_tile_common.h"

#include "vp9/decoder/vp9_dboolhuff.h"
#include "vp9/decoder/vp9_decodframe.h"
#include "vp9/decoder/vp9_detokenize.h"
#include "vp9/decoder/vp9_decodemv.h"
#include "vp9/decoder/vp9_dsubexp.h"
#include "vp9/decoder/vp9_onyxd_int.h"
#include "vp9/decoder/vp9_read_bit_buffer.h"
#include "vp9/decoder/vp9_thread.h"
#include "vp9/decoder/vp9_treereader.h"

static int read_be32(const uint8_t *p) {
  return (p[0] << 24) | (p[1] << 16) | (p[2] << 8) | p[3];
}

// len == 0 is not allowed
static int read_is_valid(const uint8_t *start, size_t len, const uint8_t *end) {
  return start + len > start && start + len <= end;
}

static int decode_unsigned_max(struct vp9_read_bit_buffer *rb, int max) {
  const int data = vp9_rb_read_literal(rb, get_unsigned_bits(max));
  return data > max ? max : data;
}

static TX_MODE read_tx_mode(vp9_reader *r) {
  TX_MODE tx_mode = vp9_read_literal(r, 2);
  if (tx_mode == ALLOW_32X32)
    tx_mode += vp9_read_bit(r);
  return tx_mode;
}

static void read_tx_probs(struct tx_probs *tx_probs, vp9_reader *r) {
  int i, j;

  for (i = 0; i < TX_SIZE_CONTEXTS; ++i)
    for (j = 0; j < TX_SIZES - 3; ++j)
      vp9_diff_update_prob(r, MODE_UPDATE_PROB, &tx_probs->p8x8[i][j]);

  for (i = 0; i < TX_SIZE_CONTEXTS; ++i)
    for (j = 0; j < TX_SIZES - 2; ++j)
      vp9_diff_update_prob(r, MODE_UPDATE_PROB, &tx_probs->p16x16[i][j]);

  for (i = 0; i < TX_SIZE_CONTEXTS; ++i)
    for (j = 0; j < TX_SIZES - 1; ++j)
      vp9_diff_update_prob(r, MODE_UPDATE_PROB, &tx_probs->p32x32[i][j]);
}

static void setup_plane_dequants(VP9_COMMON *cm, MACROBLOCKD *xd, int q_index) {
  int i;
  xd->plane[0].dequant = cm->y_dequant[q_index];

  for (i = 1; i < MAX_MB_PLANE; i++)
    xd->plane[i].dequant = cm->uv_dequant[q_index];
}

static void decode_block(int plane, int block, BLOCK_SIZE plane_bsize,
                         TX_SIZE tx_size, void *arg) {
  MACROBLOCKD* const xd = arg;
  struct macroblockd_plane *const pd = &xd->plane[plane];
  int16_t* const qcoeff = BLOCK_OFFSET(pd->qcoeff, block);
  const int stride = pd->dst.stride;
  const int eob = pd->eobs[block];
  if (eob > 0) {
    TX_TYPE tx_type;
    const int raster_block = txfrm_block_to_raster_block(plane_bsize, tx_size,
                                                         block);
    uint8_t* const dst = raster_block_offset_uint8(plane_bsize, raster_block,
                                                   pd->dst.buf, stride);
    switch (tx_size) {
      case TX_4X4:
        tx_type = get_tx_type_4x4(pd->plane_type, xd, raster_block);
        if (tx_type == DCT_DCT)
          xd->itxm_add(qcoeff, dst, stride, eob);
        else
          vp9_iht_add(tx_type, qcoeff, dst, stride, eob);
        break;
      case TX_8X8:
        tx_type = get_tx_type_8x8(pd->plane_type, xd);
        vp9_iht_add_8x8(tx_type, qcoeff, dst, stride, eob);
        break;
      case TX_16X16:
        tx_type = get_tx_type_16x16(pd->plane_type, xd);
        vp9_iht_add_16x16(tx_type, qcoeff, dst, stride, eob);
        break;
      case TX_32X32:
        tx_type = DCT_DCT;
        vp9_idct32x32_add(qcoeff, dst, stride, eob);
        break;
      default:
        assert(!"Invalid transform size");
    }

    if (eob == 1) {
      *((int32_t *)qcoeff) = 0;
    } else {
      if (tx_type == DCT_DCT && tx_size <= TX_16X16 && eob <= 10)
        vpx_memset(qcoeff, 0, 4 * (4 << tx_size) * sizeof(qcoeff[0]));
      else
        vpx_memset(qcoeff, 0, (16 << (tx_size << 1)) * sizeof(qcoeff[0]));
    }
  }
}

static void decode_block_intra(int plane, int block, BLOCK_SIZE plane_bsize,
                               TX_SIZE tx_size, void *arg) {
  MACROBLOCKD* const xd = arg;
  struct macroblockd_plane *const pd = &xd->plane[plane];
  MODE_INFO *const mi = xd->this_mi;
  const int raster_block = txfrm_block_to_raster_block(plane_bsize, tx_size,
                                                       block);
  uint8_t* const dst = raster_block_offset_uint8(plane_bsize, raster_block,
                                                 pd->dst.buf, pd->dst.stride);
  const MB_PREDICTION_MODE mode = (plane == 0)
        ? ((mi->mbmi.sb_type < BLOCK_8X8) ? mi->bmi[raster_block].as_mode
                                          : mi->mbmi.mode)
        : mi->mbmi.uv_mode;

  if (xd->mb_to_right_edge < 0 || xd->mb_to_bottom_edge < 0)
    extend_for_intra(xd, plane_bsize, plane, block, tx_size);

  vp9_predict_intra_block(xd, raster_block >> tx_size,
                          b_width_log2(plane_bsize), tx_size, mode,
                          dst, pd->dst.stride, dst, pd->dst.stride);

  if (!mi->mbmi.skip_coeff)
    decode_block(plane, block, plane_bsize, tx_size, arg);
}

static int decode_tokens(VP9D_COMP *pbi, BLOCK_SIZE bsize, vp9_reader *r) {
  VP9_COMMON *const cm = &pbi->common;
  MACROBLOCKD *const xd = &pbi->mb;
  MB_MODE_INFO *const mbmi = &xd->this_mi->mbmi;

  if (mbmi->skip_coeff) {
    reset_skip_context(xd, bsize);
    return -1;
  } else {
    if (cm->seg.enabled)
      setup_plane_dequants(cm, xd, vp9_get_qindex(&cm->seg, mbmi->segment_id,
                                                  cm->base_qindex));

    // TODO(dkovalev) if (!vp9_reader_has_error(r))
    return vp9_decode_tokens(pbi, r, bsize);
  }
}

static void set_offsets(VP9D_COMP *pbi, BLOCK_SIZE bsize,
                        int mi_row, int mi_col) {
  VP9_COMMON *const cm = &pbi->common;
  MACROBLOCKD *const xd = &pbi->mb;
  const int bh = num_8x8_blocks_high_lookup[bsize];
  const int bw = num_8x8_blocks_wide_lookup[bsize];
  const int offset = mi_row * cm->mode_info_stride + mi_col;

  xd->mode_info_stride = cm->mode_info_stride;

  xd->mi_8x8 = cm->mi_grid_visible + offset;
  xd->prev_mi_8x8 = cm->prev_mi_grid_visible + offset;

  // we are using the mode info context stream here
  xd->this_mi =
  xd->mi_8x8[0] = xd->mic_stream_ptr;
  xd->this_mi->mbmi.sb_type = bsize;
  xd->mic_stream_ptr++;

  // Special case: if prev_mi is NULL, the previous mode info context
  // cannot be used.
  xd->last_mi = cm->prev_mi ? xd->prev_mi_8x8[0] : NULL;

  set_skip_context(cm, xd, mi_row, mi_col);
  set_partition_seg_context(cm, xd, mi_row, mi_col);