• Home
  • Line#
  • Scopes#
  • Navigate#
  • Raw
  • Download
1 /*
2  * Copyright (c) 2017, Alliance for Open Media. All rights reserved
3  *
4  * This source code is subject to the terms of the BSD 2 Clause License and
5  * the Alliance for Open Media Patent License 1.0. If the BSD 2 Clause License
6  * was not distributed with this source code in the LICENSE file, you can
7  * obtain it at www.aomedia.org/license/software. If the Alliance for Open
8  * Media Patent License 1.0 was not distributed with this source code in the
9  * PATENTS file, you can obtain it at www.aomedia.org/license/patent.
10  */
11 
12 #include "av1/decoder/decodetxb.h"
13 
14 #include "aom_ports/mem.h"
15 #include "av1/common/idct.h"
16 #include "av1/common/scan.h"
17 #include "av1/common/txb_common.h"
18 #include "av1/decoder/decodemv.h"
19 
20 #define ACCT_STR __func__
21 
read_golomb(MACROBLOCKD * xd,aom_reader * r)22 static int read_golomb(MACROBLOCKD *xd, aom_reader *r) {
23   int x = 1;
24   int length = 0;
25   int i = 0;
26 
27   while (!i) {
28     i = aom_read_bit(r, ACCT_STR);
29     ++length;
30     if (length > 20) {
31       aom_internal_error(xd->error_info, AOM_CODEC_CORRUPT_FRAME,
32                          "Invalid length in read_golomb");
33       break;
34     }
35   }
36 
37   for (i = 0; i < length - 1; ++i) {
38     x <<= 1;
39     x += aom_read_bit(r, ACCT_STR);
40   }
41 
42   return x - 1;
43 }
44 
rec_eob_pos(const int eob_token,const int extra)45 static INLINE int rec_eob_pos(const int eob_token, const int extra) {
46   int eob = k_eob_group_start[eob_token];
47   if (eob > 2) {
48     eob += extra;
49   }
50   return eob;
51 }
52 
get_dqv(const int16_t * dequant,int coeff_idx,const qm_val_t * iqmatrix)53 static INLINE int get_dqv(const int16_t *dequant, int coeff_idx,
54                           const qm_val_t *iqmatrix) {
55   int dqv = dequant[!!coeff_idx];
56   if (iqmatrix != NULL)
57     dqv =
58         ((iqmatrix[coeff_idx] * dqv) + (1 << (AOM_QM_BITS - 1))) >> AOM_QM_BITS;
59   return dqv;
60 }
61 
read_coeffs_reverse_2d(aom_reader * r,TX_SIZE tx_size,int start_si,int end_si,const int16_t * scan,int bwl,uint8_t * levels,base_cdf_arr base_cdf,br_cdf_arr br_cdf)62 static INLINE void read_coeffs_reverse_2d(aom_reader *r, TX_SIZE tx_size,
63                                           int start_si, int end_si,
64                                           const int16_t *scan, int bwl,
65                                           uint8_t *levels,
66                                           base_cdf_arr base_cdf,
67                                           br_cdf_arr br_cdf) {
68   for (int c = end_si; c >= start_si; --c) {
69     const int pos = scan[c];
70     const int coeff_ctx = get_lower_levels_ctx_2d(levels, pos, bwl, tx_size);
71     const int nsymbs = 4;
72     int level = aom_read_symbol(r, base_cdf[coeff_ctx], nsymbs, ACCT_STR);
73     if (level > NUM_BASE_LEVELS) {
74       const int br_ctx = get_br_ctx_2d(levels, pos, bwl);
75       aom_cdf_prob *cdf = br_cdf[br_ctx];
76       for (int idx = 0; idx < COEFF_BASE_RANGE; idx += BR_CDF_SIZE - 1) {
77         const int k = aom_read_symbol(r, cdf, BR_CDF_SIZE, ACCT_STR);
78         level += k;
79         if (k < BR_CDF_SIZE - 1) break;
80       }
81     }
82     levels[get_padded_idx(pos, bwl)] = level;
83   }
84 }
85 
read_coeffs_reverse(aom_reader * r,TX_SIZE tx_size,TX_CLASS tx_class,int start_si,int end_si,const int16_t * scan,int bwl,uint8_t * levels,base_cdf_arr base_cdf,br_cdf_arr br_cdf)86 static INLINE void read_coeffs_reverse(aom_reader *r, TX_SIZE tx_size,
87                                        TX_CLASS tx_class, int start_si,
88                                        int end_si, const int16_t *scan, int bwl,
89                                        uint8_t *levels, base_cdf_arr base_cdf,
90                                        br_cdf_arr br_cdf) {
91   for (int c = end_si; c >= start_si; --c) {
92     const int pos = scan[c];
93     const int coeff_ctx =
94         get_lower_levels_ctx(levels, pos, bwl, tx_size, tx_class);
95     const int nsymbs = 4;
96     int level = aom_read_symbol(r, base_cdf[coeff_ctx], nsymbs, ACCT_STR);
97     if (level > NUM_BASE_LEVELS) {
98       const int br_ctx = get_br_ctx(levels, pos, bwl, tx_class);
99       aom_cdf_prob *cdf = br_cdf[br_ctx];
100       for (int idx = 0; idx < COEFF_BASE_RANGE; idx += BR_CDF_SIZE - 1) {
101         const int k = aom_read_symbol(r, cdf, BR_CDF_SIZE, ACCT_STR);
102         level += k;
103         if (k < BR_CDF_SIZE - 1) break;
104       }
105     }
106     levels[get_padded_idx(pos, bwl)] = level;
107   }
108 }
109 
av1_read_coeffs_txb(const AV1_COMMON * const cm,MACROBLOCKD * const xd,aom_reader * const r,const int blk_row,const int blk_col,const int plane,const TXB_CTX * const txb_ctx,const TX_SIZE tx_size)110 uint8_t av1_read_coeffs_txb(const AV1_COMMON *const cm, MACROBLOCKD *const xd,
111                             aom_reader *const r, const int blk_row,
112                             const int blk_col, const int plane,
113                             const TXB_CTX *const txb_ctx,
114                             const TX_SIZE tx_size) {
115   FRAME_CONTEXT *const ec_ctx = xd->tile_ctx;
116   const int32_t max_value = (1 << (7 + xd->bd)) - 1;
117   const int32_t min_value = -(1 << (7 + xd->bd));
118   const TX_SIZE txs_ctx = get_txsize_entropy_ctx(tx_size);
119   const PLANE_TYPE plane_type = get_plane_type(plane);
120   MB_MODE_INFO *const mbmi = xd->mi[0];
121   struct macroblockd_plane *const pd = &xd->plane[plane];
122   const int16_t *const dequant = pd->seg_dequant_QTX[mbmi->segment_id];
123   tran_low_t *const tcoeffs = pd->dqcoeff_block + xd->cb_offset[plane];
124   const int shift = av1_get_tx_scale(tx_size);
125   const int bwl = get_txb_bwl(tx_size);
126   const int width = get_txb_wide(tx_size);
127   const int height = get_txb_high(tx_size);
128   int cul_level = 0;
129   int dc_val = 0;
130   uint8_t levels_buf[TX_PAD_2D];
131   uint8_t *const levels = set_levels(levels_buf, width);
132   const int all_zero = aom_read_symbol(
133       r, ec_ctx->txb_skip_cdf[txs_ctx][txb_ctx->txb_skip_ctx], 2, ACCT_STR);
134   eob_info *eob_data = pd->eob_data + xd->txb_offset[plane];
135   uint16_t *const eob = &(eob_data->eob);
136   uint16_t *const max_scan_line = &(eob_data->max_scan_line);
137   *max_scan_line = 0;
138   *eob = 0;
139 
140 #if CONFIG_INSPECTION
141   if (plane == 0) {
142     const int txk_type_idx =
143         av1_get_txk_type_index(mbmi->sb_type, blk_row, blk_col);
144     mbmi->tx_skip[txk_type_idx] = all_zero;
145   }
146 #endif
147 
148   if (all_zero) {
149     *max_scan_line = 0;
150     if (plane == 0) {
151       const int txk_type_idx =
152           av1_get_txk_type_index(mbmi->sb_type, blk_row, blk_col);
153       mbmi->txk_type[txk_type_idx] = DCT_DCT;
154     }
155     return 0;
156   }
157 
158   if (plane == AOM_PLANE_Y) {
159     // only y plane's tx_type is transmitted
160     av1_read_tx_type(cm, xd, blk_row, blk_col, tx_size, r);
161   }
162   const TX_TYPE tx_type = av1_get_tx_type(plane_type, xd, blk_row, blk_col,
163                                           tx_size, cm->reduced_tx_set_used);
164   const TX_CLASS tx_class = tx_type_to_class[tx_type];
165   const TX_SIZE qm_tx_size = av1_get_adjusted_tx_size(tx_size);
166   const qm_val_t *iqmatrix =
167       IS_2D_TRANSFORM(tx_type)
168           ? pd->seg_iqmatrix[mbmi->segment_id][qm_tx_size]
169           : cm->giqmatrix[NUM_QM_LEVELS - 1][0][qm_tx_size];
170   const SCAN_ORDER *const scan_order = get_scan(tx_size, tx_type);
171   const int16_t *const scan = scan_order->scan;
172   int eob_extra = 0;
173   int eob_pt = 1;
174 
175   const int eob_multi_size = txsize_log2_minus4[tx_size];
176   const int eob_multi_ctx = (tx_class == TX_CLASS_2D) ? 0 : 1;
177   switch (eob_multi_size) {
178     case 0:
179       eob_pt =
180           aom_read_symbol(r, ec_ctx->eob_flag_cdf16[plane_type][eob_multi_ctx],
181                           5, ACCT_STR) +
182           1;
183       break;
184     case 1:
185       eob_pt =
186           aom_read_symbol(r, ec_ctx->eob_flag_cdf32[plane_type][eob_multi_ctx],
187                           6, ACCT_STR) +
188           1;
189       break;
190     case 2:
191       eob_pt =
192           aom_read_symbol(r, ec_ctx->eob_flag_cdf64[plane_type][eob_multi_ctx],
193                           7, ACCT_STR) +
194           1;
195       break;
196     case 3:
197       eob_pt =
198           aom_read_symbol(r, ec_ctx->eob_flag_cdf128[plane_type][eob_multi_ctx],
199                           8, ACCT_STR) +
200           1;
201       break;
202     case 4:
203       eob_pt =
204           aom_read_symbol(r, ec_ctx->eob_flag_cdf256[plane_type][eob_multi_ctx],
205                           9, ACCT_STR) +
206           1;
207       break;
208     case 5:
209       eob_pt =
210           aom_read_symbol(r, ec_ctx->eob_flag_cdf512[plane_type][eob_multi_ctx],
211                           10, ACCT_STR) +
212           1;
213       break;
214     case 6:
215     default:
216       eob_pt = aom_read_symbol(
217                    r, ec_ctx->eob_flag_cdf1024[plane_type][eob_multi_ctx], 11,
218                    ACCT_STR) +
219                1;
220       break;
221   }
222 
223   const int eob_offset_bits = k_eob_offset_bits[eob_pt];
224   if (eob_offset_bits > 0) {
225     const int eob_ctx = eob_pt - 3;
226     int bit = aom_read_symbol(
227         r, ec_ctx->eob_extra_cdf[txs_ctx][plane_type][eob_ctx], 2, ACCT_STR);
228     if (bit) {
229       eob_extra += (1 << (eob_offset_bits - 1));
230     }
231 
232     for (int i = 1; i < eob_offset_bits; i++) {
233       bit = aom_read_bit(r, ACCT_STR);
234       if (bit) {
235         eob_extra += (1 << (eob_offset_bits - 1 - i));
236       }
237     }
238   }
239   *eob = rec_eob_pos(eob_pt, eob_extra);
240 
241   if (*eob > 1) {
242     memset(levels_buf, 0,
243            sizeof(*levels_buf) *
244                ((width + TX_PAD_HOR) * (height + TX_PAD_VER) + TX_PAD_END));
245   }
246 
247   {
248     // Read the non-zero coefficient with scan index eob-1
249     // TODO(angiebird): Put this into a function
250     const int c = *eob - 1;
251     const int pos = scan[c];
252     const int coeff_ctx = get_lower_levels_ctx_eob(bwl, height, c);
253     const int nsymbs = 3;
254     aom_cdf_prob *cdf =
255         ec_ctx->coeff_base_eob_cdf[txs_ctx][plane_type][coeff_ctx];
256     int level = aom_read_symbol(r, cdf, nsymbs, ACCT_STR) + 1;
257     if (level > NUM_BASE_LEVELS) {
258       const int br_ctx = get_br_ctx_eob(pos, bwl, tx_class);
259       cdf = ec_ctx->coeff_br_cdf[AOMMIN(txs_ctx, TX_32X32)][plane_type][br_ctx];
260       for (int idx = 0; idx < COEFF_BASE_RANGE; idx += BR_CDF_SIZE - 1) {
261         const int k = aom_read_symbol(r, cdf, BR_CDF_SIZE, ACCT_STR);
262         level += k;
263         if (k < BR_CDF_SIZE - 1) break;
264       }
265     }
266     levels[get_padded_idx(pos, bwl)] = level;
267   }
268   if (*eob > 1) {
269     base_cdf_arr base_cdf = ec_ctx->coeff_base_cdf[txs_ctx][plane_type];
270     br_cdf_arr br_cdf =
271         ec_ctx->coeff_br_cdf[AOMMIN(txs_ctx, TX_32X32)][plane_type];
272     if (tx_class == TX_CLASS_2D) {
273       read_coeffs_reverse_2d(r, tx_size, 1, *eob - 1 - 1, scan, bwl, levels,
274                              base_cdf, br_cdf);
275       read_coeffs_reverse(r, tx_size, tx_class, 0, 0, scan, bwl, levels,
276                           base_cdf, br_cdf);
277     } else {
278       read_coeffs_reverse(r, tx_size, tx_class, 0, *eob - 1 - 1, scan, bwl,
279                           levels, base_cdf, br_cdf);
280     }
281   }
282 
283   for (int c = 0; c < *eob; ++c) {
284     const int pos = scan[c];
285     uint8_t sign;
286     tran_low_t level = levels[get_padded_idx(pos, bwl)];
287     if (level) {
288       *max_scan_line = AOMMAX(*max_scan_line, pos);
289       if (c == 0) {
290         const int dc_sign_ctx = txb_ctx->dc_sign_ctx;
291         sign = aom_read_symbol(r, ec_ctx->dc_sign_cdf[plane_type][dc_sign_ctx],
292                                2, ACCT_STR);
293       } else {
294         sign = aom_read_bit(r, ACCT_STR);
295       }
296       if (level >= MAX_BASE_BR_RANGE) {
297         level += read_golomb(xd, r);
298       }
299 
300       if (c == 0) dc_val = sign ? -level : level;
301 
302       // Bitmasking to clamp level to valid range:
303       //   The valid range for 8/10/12 bit vdieo is at most 14/16/18 bit
304       level &= 0xfffff;
305       cul_level += level;
306       tran_low_t dq_coeff;
307       // Bitmasking to clamp dq_coeff to valid range:
308       //   The valid range for 8/10/12 bit video is at most 17/19/21 bit
309       dq_coeff = (tran_low_t)(
310           (int64_t)level * get_dqv(dequant, scan[c], iqmatrix) & 0xffffff);
311       dq_coeff = dq_coeff >> shift;
312       if (sign) {
313         dq_coeff = -dq_coeff;
314       }
315       tcoeffs[pos] = clamp(dq_coeff, min_value, max_value);
316     }
317   }
318 
319   cul_level = AOMMIN(COEFF_CONTEXT_MASK, cul_level);
320 
321   // DC value
322   set_dc_sign(&cul_level, dc_val);
323 
324   return cul_level;
325 }
326 
av1_read_coeffs_txb_facade(const AV1_COMMON * const cm,MACROBLOCKD * const xd,aom_reader * const r,const int plane,const int row,const int col,const TX_SIZE tx_size)327 void av1_read_coeffs_txb_facade(const AV1_COMMON *const cm,
328                                 MACROBLOCKD *const xd, aom_reader *const r,
329                                 const int plane, const int row, const int col,
330                                 const TX_SIZE tx_size) {
331 #if TXCOEFF_TIMER
332   struct aom_usec_timer timer;
333   aom_usec_timer_start(&timer);
334 #endif
335   MB_MODE_INFO *const mbmi = xd->mi[0];
336   struct macroblockd_plane *const pd = &xd->plane[plane];
337 
338   const BLOCK_SIZE bsize = mbmi->sb_type;
339   const BLOCK_SIZE plane_bsize =
340       get_plane_block_size(bsize, pd->subsampling_x, pd->subsampling_y);
341 
342   TXB_CTX txb_ctx;
343   get_txb_ctx(plane_bsize, tx_size, plane, pd->above_context + col,
344               pd->left_context + row, &txb_ctx);
345   const uint8_t cul_level =
346       av1_read_coeffs_txb(cm, xd, r, row, col, plane, &txb_ctx, tx_size);
347   av1_set_contexts(xd, pd, plane, plane_bsize, tx_size, cul_level, col, row);
348 
349   if (is_inter_block(mbmi)) {
350     PLANE_TYPE plane_type = get_plane_type(plane);
351     // tx_type will be read out in av1_read_coeffs_txb_facade
352     const TX_TYPE tx_type = av1_get_tx_type(plane_type, xd, row, col, tx_size,
353                                             cm->reduced_tx_set_used);
354 
355     if (plane == 0)
356       update_txk_array(mbmi->txk_type, mbmi->sb_type, row, col, tx_size,
357                        tx_type);
358   }
359 
360 #if TXCOEFF_TIMER
361   aom_usec_timer_mark(&timer);
362   const int64_t elapsed_time = aom_usec_timer_elapsed(&timer);
363   cm->txcoeff_timer += elapsed_time;
364   ++cm->txb_count;
365 #endif
366 }
367