libvpx: Add VP9 decoder.

source/libvpx/vp9/decoder/vp9_detokenize.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/common/vp9_type_aliases.h"
+#include "vp9/common/vp9_blockd.h"
+#include "vp9/decoder/vp9_onyxd_int.h"
+#include "vpx_mem/vpx_mem.h"
+#include "vpx_ports/mem.h"
+#include "vp9/decoder/vp9_detokenize.h"
+
+#include "vp9/common/vp9_seg_common.h"
+
+#define EOB_CONTEXT_NODE            0
+#define ZERO_CONTEXT_NODE           1
+#define ONE_CONTEXT_NODE            2
+#define LOW_VAL_CONTEXT_NODE        3
+#define TWO_CONTEXT_NODE            4
+#define THREE_CONTEXT_NODE          5
+#define HIGH_LOW_CONTEXT_NODE       6
+#define CAT_ONE_CONTEXT_NODE        7
+#define CAT_THREEFOUR_CONTEXT_NODE  8
+#define CAT_THREE_CONTEXT_NODE      9
+#define CAT_FIVE_CONTEXT_NODE       10
+
+#define CAT1_MIN_VAL    5
+#define CAT2_MIN_VAL    7
+#define CAT3_MIN_VAL   11
+#define CAT4_MIN_VAL   19
+#define CAT5_MIN_VAL   35
+#define CAT6_MIN_VAL   67
+#define CAT1_PROB0    159
+#define CAT2_PROB0    145
+#define CAT2_PROB1    165
+
+#define CAT3_PROB0 140
+#define CAT3_PROB1 148
+#define CAT3_PROB2 173
+
+#define CAT4_PROB0 135
+#define CAT4_PROB1 140
+#define CAT4_PROB2 155
+#define CAT4_PROB3 176
+
+#define CAT5_PROB0 130
+#define CAT5_PROB1 134
+#define CAT5_PROB2 141
+#define CAT5_PROB3 157
+#define CAT5_PROB4 180
+
+static const unsigned char cat6_prob[14] =
+{ 254, 254, 252, 249, 243, 230, 196, 177, 153, 140, 133, 130, 129, 0 };
+
+void vp9_reset_mb_tokens_context(MACROBLOCKD* const xd) {
+  /* Clear entropy contexts */
+  if ((xd->mode_info_context->mbmi.mode != B_PRED &&
+       xd->mode_info_context->mbmi.mode != I8X8_PRED &&
+       xd->mode_info_context->mbmi.mode != SPLITMV)
+      || xd->mode_info_context->mbmi.txfm_size == TX_16X16) {
+    vpx_memset(xd->above_context, 0, sizeof(ENTROPY_CONTEXT_PLANES));
+    vpx_memset(xd->left_context, 0, sizeof(ENTROPY_CONTEXT_PLANES));
+  } else {
+    vpx_memset(xd->above_context, 0, sizeof(ENTROPY_CONTEXT_PLANES) - 1);
+    vpx_memset(xd->left_context, 0, sizeof(ENTROPY_CONTEXT_PLANES) - 1);
+    xd->above_context->y2 = 1;
+    xd->left_context->y2 = 1;
+  }
+}
+
+DECLARE_ALIGNED(16, extern const unsigned char, vp9_norm[256]);
+
+static int get_signed(BOOL_DECODER *br, int value_to_sign) {
+  const int split = (br->range + 1) >> 1;
+  const VP9_BD_VALUE bigsplit = (VP9_BD_VALUE)split << (VP9_BD_VALUE_SIZE - 8);
+  int v;
+
+  if (br->count < 0)
+    vp9_bool_decoder_fill(br);
+
+  if (br->value < bigsplit) {
+    br->range = split;
+    v = value_to_sign;
+  } else {
+    br->range = br->range - split;
+    br->value = br->value - bigsplit;
+    v = -value_to_sign;
+  }
+  br->range += br->range;
+  br->value += br->value;
+  --br->count;
+
+  return v;
+}
+
+#define INCREMENT_COUNT(token)               \
+  do {                                       \
+    coef_counts[coef_bands[c]][pt][token]++; \
+    pt = vp9_prev_token_class[token];        \
+  } while (0)
+
+#define WRITE_COEF_CONTINUE(val, token)                       \
+  {                                                           \
+    qcoeff_ptr[scan[c]] = (INT16) get_signed(br, val);        \
+    INCREMENT_COUNT(token);                                   \
+    c++;                                                      \
+    continue;                                                 \
+  }
+
+#define ADJUST_COEF(prob, bits_count)  \
+  do {                                 \
+    if (vp9_read(br, prob))            \
+      val += (UINT16)(1 << bits_count);\
+  } while (0);
+
+static int decode_coefs(VP9D_COMP *dx, const MACROBLOCKD *xd,
+                        BOOL_DECODER* const br,
+                        ENTROPY_CONTEXT *a, ENTROPY_CONTEXT *l,
+                        PLANE_TYPE type,
+                        TX_TYPE tx_type,
+                        int seg_eob, INT16 *qcoeff_ptr,
+                        const int *const scan, TX_SIZE txfm_size,
+                        const int *coef_bands) {
+  FRAME_CONTEXT *const fc = &dx->common.fc;
+  int pt, c = (type == PLANE_TYPE_Y_NO_DC);
+  vp9_prob (*coef_probs)[PREV_COEF_CONTEXTS][ENTROPY_NODES], *prob;
+  unsigned int (*coef_counts)[PREV_COEF_CONTEXTS][MAX_ENTROPY_TOKENS];
+
+  switch (txfm_size) {
+    default:
+    case TX_4X4:
+      if (tx_type == DCT_DCT) {
+        coef_probs  = fc->coef_probs[type];
+        coef_counts = fc->coef_counts[type];
+      } else {
+        coef_probs  = fc->hybrid_coef_probs[type];
+        coef_counts = fc->hybrid_coef_counts[type];
+      }
+      break;
+    case TX_8X8:
+      if (tx_type == DCT_DCT) {
+        coef_probs  = fc->coef_probs_8x8[type];
+        coef_counts = fc->coef_counts_8x8[type];
+      } else {
+        coef_probs  = fc->hybrid_coef_probs_8x8[type];
+        coef_counts = fc->hybrid_coef_counts_8x8[type];
+      }
+      break;
+    case TX_16X16:
+      if (tx_type == DCT_DCT) {
+        coef_probs  = fc->coef_probs_16x16[type];
+        coef_counts = fc->coef_counts_16x16[type];
+      } else {
+        coef_probs  = fc->hybrid_coef_probs_16x16[type];
+        coef_counts = fc->hybrid_coef_counts_16x16[type];
+      }
+      break;
+  }
+
+  VP9_COMBINEENTROPYCONTEXTS(pt, *a, *l);
+  while (1) {
+    int val;
+    const uint8_t *cat6 = cat6_prob;
+    if (c >= seg_eob) break;
+    prob = coef_probs[coef_bands[c]][pt];
+    if (!vp9_read(br, prob[EOB_CONTEXT_NODE]))
+      break;
+SKIP_START:
+    if (c >= seg_eob) break;
+    if (!vp9_read(br, prob[ZERO_CONTEXT_NODE])) {
+      INCREMENT_COUNT(ZERO_TOKEN);
+      ++c;
+      prob = coef_probs[coef_bands[c]][pt];
+      goto SKIP_START;
+    }
+    // ONE_CONTEXT_NODE_0_
+    if (!vp9_read(br, prob[ONE_CONTEXT_NODE])) {
+      WRITE_COEF_CONTINUE(1, ONE_TOKEN);
+    }
+    // LOW_VAL_CONTEXT_NODE_0_
+    if (!vp9_read(br, prob[LOW_VAL_CONTEXT_NODE])) {
+      if (!vp9_read(br, prob[TWO_CONTEXT_NODE])) {
+        WRITE_COEF_CONTINUE(2, TWO_TOKEN);
+      }
+      if (!vp9_read(br, prob[THREE_CONTEXT_NODE])) {
+        WRITE_COEF_CONTINUE(3, THREE_TOKEN);
+      }
+      WRITE_COEF_CONTINUE(4, FOUR_TOKEN);
+    }
+    // HIGH_LOW_CONTEXT_NODE_0_
+    if (!vp9_read(br, prob[HIGH_LOW_CONTEXT_NODE])) {
+      if (!vp9_read(br, prob[CAT_ONE_CONTEXT_NODE])) {
+        val = CAT1_MIN_VAL;
+        ADJUST_COEF(CAT1_PROB0, 0);
+        WRITE_COEF_CONTINUE(val, DCT_VAL_CATEGORY1);
+      }
+      val = CAT2_MIN_VAL;
+      ADJUST_COEF(CAT2_PROB1, 1);
+      ADJUST_COEF(CAT2_PROB0, 0);
+      WRITE_COEF_CONTINUE(val, DCT_VAL_CATEGORY2);
+    }
+    // CAT_THREEFOUR_CONTEXT_NODE_0_
+    if (!vp9_read(br, prob[CAT_THREEFOUR_CONTEXT_NODE])) {
+      if (!vp9_read(br, prob[CAT_THREE_CONTEXT_NODE])) {
+        val = CAT3_MIN_VAL;
+        ADJUST_COEF(CAT3_PROB2, 2);
+        ADJUST_COEF(CAT3_PROB1, 1);
+        ADJUST_COEF(CAT3_PROB0, 0);
+        WRITE_COEF_CONTINUE(val, DCT_VAL_CATEGORY3);
+      }
+      val = CAT4_MIN_VAL;
+      ADJUST_COEF(CAT4_PROB3, 3);
+      ADJUST_COEF(CAT4_PROB2, 2);
+      ADJUST_COEF(CAT4_PROB1, 1);
+      ADJUST_COEF(CAT4_PROB0, 0);
+      WRITE_COEF_CONTINUE(val, DCT_VAL_CATEGORY4);
+    }
+    // CAT_FIVE_CONTEXT_NODE_0_:
+    if (!vp9_read(br, prob[CAT_FIVE_CONTEXT_NODE])) {
+      val = CAT5_MIN_VAL;
+      ADJUST_COEF(CAT5_PROB4, 4);
+      ADJUST_COEF(CAT5_PROB3, 3);
+      ADJUST_COEF(CAT5_PROB2, 2);
+      ADJUST_COEF(CAT5_PROB1, 1);
+      ADJUST_COEF(CAT5_PROB0, 0);
+      WRITE_COEF_CONTINUE(val, DCT_VAL_CATEGORY5);
+    }
+    val = 0;
+    while (*cat6) {
+      val = (val << 1) | vp9_read(br, *cat6++);
+    }
+    val += CAT6_MIN_VAL;
+    WRITE_COEF_CONTINUE(val, DCT_VAL_CATEGORY6);
+  }
+
+  if (c < seg_eob)
+    coef_counts[coef_bands[c]][pt][DCT_EOB_TOKEN]++;
+
+  a[0] = l[0] = (c > !type);
+
+  return c;
+}
+
+static int get_eob(MACROBLOCKD* const xd, int segment_id, int eob_max) {
+  int active = vp9_segfeature_active(xd, segment_id, SEG_LVL_EOB);
+  int eob = vp9_get_segdata(xd, segment_id, SEG_LVL_EOB);
+
+  if (!active || eob > eob_max)
+    eob = eob_max;
+  return eob;
+}
+
+
+static int vp9_decode_mb_tokens_16x16(VP9D_COMP* const pbi,
+                                      MACROBLOCKD* const xd,
+                                      BOOL_DECODER* const bc) {
+  ENTROPY_CONTEXT* const A = (ENTROPY_CONTEXT *)xd->above_context;
+  ENTROPY_CONTEXT* const L = (ENTROPY_CONTEXT *)xd->left_context;
+  unsigned short* const eobs = xd->eobs;
+  const int segment_id = xd->mode_info_context->mbmi.segment_id;
+  int c, i, eobtotal = 0, seg_eob;
+
+  // Luma block
+  eobs[0] = c = decode_coefs(pbi, xd, bc, A, L, PLANE_TYPE_Y_WITH_DC,
+                             get_tx_type(xd, &xd->block[0]),
+                             get_eob(xd, segment_id, 256),
+                             xd->qcoeff, vp9_default_zig_zag1d_16x16,
+                             TX_16X16, vp9_coef_bands_16x16);
+  A[1] = A[2] = A[3] = A[0];
+  L[1] = L[2] = L[3] = L[0];
+  eobtotal += c;
+
+  // 8x8 chroma blocks
+  seg_eob = get_eob(xd, segment_id, 64);
+  for (i = 16; i < 24; i += 4) {
+    ENTROPY_CONTEXT* const a = A + vp9_block2above_8x8[i];
+    ENTROPY_CONTEXT* const l = L + vp9_block2left_8x8[i];
+
+    eobs[i] = c = decode_coefs(pbi, xd, bc, a, l, PLANE_TYPE_UV,
+                               DCT_DCT, seg_eob, xd->block[i].qcoeff,
+                               vp9_default_zig_zag1d_8x8,
+                               TX_8X8, vp9_coef_bands_8x8);
+    a[1] = a[0];
+    l[1] = l[0];
+    eobtotal += c;
+  }
+  A[8] = 0;
+  L[8] = 0;
+  return eobtotal;
+}
+
+static int vp9_decode_mb_tokens_8x8(VP9D_COMP* const pbi,
+                                    MACROBLOCKD* const xd,
+                                    BOOL_DECODER* const bc) {
+  ENTROPY_CONTEXT *const A = (ENTROPY_CONTEXT *)xd->above_context;
+  ENTROPY_CONTEXT *const L = (ENTROPY_CONTEXT *)xd->left_context;
+  unsigned short *const eobs = xd->eobs;
+  PLANE_TYPE type;
+  int c, i, eobtotal = 0, seg_eob;
+  const int segment_id = xd->mode_info_context->mbmi.segment_id;
+
+  int has_2nd_order = get_2nd_order_usage(xd);
+  // 2nd order DC block
+  if (has_2nd_order) {
+    ENTROPY_CONTEXT *const a = A + vp9_block2above_8x8[24];
+    ENTROPY_CONTEXT *const l = L + vp9_block2left_8x8[24];
+
+    eobs[24] = c = decode_coefs(pbi, xd, bc, a, l, PLANE_TYPE_Y2,
+                                DCT_DCT, get_eob(xd, segment_id, 4),
+                                xd->block[24].qcoeff,
+                                vp9_default_zig_zag1d, TX_8X8, vp9_coef_bands);
+    eobtotal += c - 4;
+    type = PLANE_TYPE_Y_NO_DC;
+  } else {
+    xd->above_context->y2 = 1;
+    xd->left_context->y2 = 1;
+    eobs[24] = 0;
+    type = PLANE_TYPE_Y_WITH_DC;
+  }
+
+  // luma blocks
+  seg_eob = get_eob(xd, segment_id, 64);
+  for (i = 0; i < 16; i += 4) {
+    ENTROPY_CONTEXT *const a = A + vp9_block2above_8x8[i];
+    ENTROPY_CONTEXT *const l = L + vp9_block2left_8x8[i];
+
+    eobs[i] = c = decode_coefs(pbi, xd, bc, a, l, type,
+                               type == PLANE_TYPE_Y_WITH_DC ?
+                               get_tx_type(xd, xd->block + i) : DCT_DCT,
+                               seg_eob, xd->block[i].qcoeff,
+                               vp9_default_zig_zag1d_8x8,
+                               TX_8X8, vp9_coef_bands_8x8);
+    a[1] = a[0];
+    l[1] = l[0];
+    eobtotal += c;
+  }
+
+  // chroma blocks
+  if (xd->mode_info_context->mbmi.mode == I8X8_PRED ||
+      xd->mode_info_context->mbmi.mode == SPLITMV) {
+    // use 4x4 transform for U, V components in I8X8/splitmv prediction mode
+    seg_eob = get_eob(xd, segment_id, 16);
+    for (i = 16; i < 24; i++) {
+      ENTROPY_CONTEXT *const a = A + vp9_block2above[i];
+      ENTROPY_CONTEXT *const l = L + vp9_block2left[i];
+
+      eobs[i] = c = decode_coefs(pbi, xd, bc, a, l, PLANE_TYPE_UV,
+                                 DCT_DCT, seg_eob, xd->block[i].qcoeff,
+                                 vp9_default_zig_zag1d, TX_4X4, vp9_coef_bands);
+      eobtotal += c;
+    }
+  } else {
+    for (i = 16; i < 24; i += 4) {
+      ENTROPY_CONTEXT *const a = A + vp9_block2above_8x8[i];
+      ENTROPY_CONTEXT *const l = L + vp9_block2left_8x8[i];
+
+      eobs[i] = c = decode_coefs(pbi, xd, bc, a, l, PLANE_TYPE_UV,
+                                 DCT_DCT, seg_eob, xd->block[i].qcoeff,
+                                 vp9_default_zig_zag1d_8x8,
+                                 TX_8X8, vp9_coef_bands_8x8);
+      a[1] = a[0];
+      l[1] = l[0];
+      eobtotal += c;
+    }
+  }
+
+  return eobtotal;
+}
+
+int vp9_decode_coefs_4x4(VP9D_COMP *dx, MACROBLOCKD *xd,
+                         BOOL_DECODER* const bc,
+                         PLANE_TYPE type, int i) {
+  ENTROPY_CONTEXT *const A = (ENTROPY_CONTEXT *)xd->above_context;
+  ENTROPY_CONTEXT *const L = (ENTROPY_CONTEXT *)xd->left_context;
+  ENTROPY_CONTEXT *const a = A + vp9_block2above[i];
+  ENTROPY_CONTEXT *const l = L + vp9_block2left[i];
+  INT16 *qcoeff_ptr = &xd->qcoeff[0];
+  const int *scan = vp9_default_zig_zag1d;
+  unsigned short *const eobs = xd->eobs;
+  int segment_id = xd->mode_info_context->mbmi.segment_id;
+  int c, seg_eob = get_eob(xd, segment_id, 16);
+  TX_TYPE tx_type = DCT_DCT;
+
+  if (type == PLANE_TYPE_Y_WITH_DC)
+    tx_type = get_tx_type_4x4(xd, &xd->block[i]);
+  switch (tx_type) {
+    case ADST_DCT :
+      scan = vp9_row_scan;
+      break;
+
+    case DCT_ADST :
+      scan = vp9_col_scan;
+      break;
+
+    default :
+      scan = vp9_default_zig_zag1d;
+      break;
+  }
+  eobs[i] = c = decode_coefs(dx, xd, bc, a, l, type,
+                             tx_type, seg_eob, qcoeff_ptr + i * 16,
+                             scan, TX_4X4, vp9_coef_bands);
+  return c;
+}
+
+int vp9_decode_mb_tokens_4x4_uv(VP9D_COMP* const dx,
+                                MACROBLOCKD* const xd,
+                                BOOL_DECODER* const bc) {
+  int eobtotal = 0, i;
+
+  for (i = 16; i < 24; i++)
+    eobtotal += vp9_decode_coefs_4x4(dx, xd, bc, PLANE_TYPE_UV, i);
+
+  return eobtotal;
+}
+
+static int vp9_decode_mb_tokens_4x4(VP9D_COMP* const dx,
+                                    MACROBLOCKD* const xd,
+                                    BOOL_DECODER* const bc) {
+  int i, eobtotal = 0;
+  PLANE_TYPE type;
+
+  int has_2nd_order = get_2nd_order_usage(xd);
+
+  if (has_2nd_order) {
+    eobtotal += vp9_decode_coefs_4x4(dx, xd, bc, PLANE_TYPE_Y2, 24) - 16;
+    type = PLANE_TYPE_Y_NO_DC;
+  } else {
+    xd->above_context->y2 = 1;
+    xd->left_context->y2 = 1;
+    xd->eobs[24] = 0;
+    type = PLANE_TYPE_Y_WITH_DC;
+  }
+
+  for (i = 0; i < 16; ++i) {
+    eobtotal += vp9_decode_coefs_4x4(dx, xd, bc, type, i);
+  }
+
+  return eobtotal + vp9_decode_mb_tokens_4x4_uv(dx, xd, bc);
+}
+
+int vp9_decode_mb_tokens(VP9D_COMP* const dx,
+                         MACROBLOCKD* const xd,
+                         BOOL_DECODER* const bc) {
+  const TX_SIZE tx_size = xd->mode_info_context->mbmi.txfm_size;
+  int eobtotal;
+
+  if (tx_size == TX_16X16) {
+    eobtotal = vp9_decode_mb_tokens_16x16(dx, xd, bc);
+  } else if (tx_size == TX_8X8) {
+    eobtotal = vp9_decode_mb_tokens_8x8(dx, xd, bc);
+  } else {
+    assert(tx_size == TX_4X4);
+    eobtotal = vp9_decode_mb_tokens_4x4(dx, xd, bc);
+  }
+
+  return eobtotal;
+}