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rv30.c
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1 /*
2  * RV30 decoder
3  * Copyright (c) 2007 Konstantin Shishkov
4  *
5  * This file is part of FFmpeg.
6  *
7  * FFmpeg is free software; you can redistribute it and/or
8  * modify it under the terms of the GNU Lesser General Public
9  * License as published by the Free Software Foundation; either
10  * version 2.1 of the License, or (at your option) any later version.
11  *
12  * FFmpeg is distributed in the hope that it will be useful,
13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15  * Lesser General Public License for more details.
16  *
17  * You should have received a copy of the GNU Lesser General Public
18  * License along with FFmpeg; if not, write to the Free Software
19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20  */
21 
22 /**
23  * @file
24  * RV30 decoder
25  */
26 
27 #include "avcodec.h"
28 #include "mpegvideo.h"
29 #include "golomb.h"
30 
31 #include "rv34.h"
32 #include "rv30data.h"
33 
34 
36 {
37  int mb_bits;
38  int w = r->s.width, h = r->s.height;
39  int mb_size;
40  int rpr;
41 
42  memset(si, 0, sizeof(SliceInfo));
43  if(get_bits(gb, 3))
44  return -1;
45  si->type = get_bits(gb, 2);
46  if(si->type == 1) si->type = 0;
47  if(get_bits1(gb))
48  return -1;
49  si->quant = get_bits(gb, 5);
50  skip_bits1(gb);
51  si->pts = get_bits(gb, 13);
52  rpr = get_bits(gb, r->rpr);
53  if (r->s.avctx->extradata_size < 8 + rpr*2) {
55  "Extradata does not contain selected resolution\n");
56  rpr = 0;
57  }
58  if(rpr){
59  w = r->s.avctx->extradata[6 + rpr*2] << 2;
60  h = r->s.avctx->extradata[7 + rpr*2] << 2;
61  }
62  si->width = w;
63  si->height = h;
64  mb_size = ((w + 15) >> 4) * ((h + 15) >> 4);
65  mb_bits = ff_rv34_get_start_offset(gb, mb_size);
66  si->start = get_bits(gb, mb_bits);
67  skip_bits1(gb);
68  return 0;
69 }
70 
71 /**
72  * Decode 4x4 intra types array.
73  */
75 {
76  int i, j, k;
77 
78  for(i = 0; i < 4; i++, dst += r->intra_types_stride - 4){
79  for(j = 0; j < 4; j+= 2){
80  unsigned code = svq3_get_ue_golomb(gb) << 1;
81  if (code > 80U*2U) {
82  av_log(r->s.avctx, AV_LOG_ERROR, "Incorrect intra prediction code\n");
83  return -1;
84  }
85  for(k = 0; k < 2; k++){
86  int A = dst[-r->intra_types_stride] + 1;
87  int B = dst[-1] + 1;
88  *dst++ = rv30_itype_from_context[A * 90 + B * 9 + rv30_itype_code[code + k]];
89  if(dst[-1] == 9){
90  av_log(r->s.avctx, AV_LOG_ERROR, "Incorrect intra prediction mode\n");
91  return -1;
92  }
93  }
94  }
95  }
96  return 0;
97 }
98 
99 /**
100  * Decode macroblock information.
101  */
103 {
104  static const int rv30_p_types[6] = { RV34_MB_SKIP, RV34_MB_P_16x16, RV34_MB_P_8x8, -1, RV34_MB_TYPE_INTRA, RV34_MB_TYPE_INTRA16x16 };
106  MpegEncContext *s = &r->s;
107  GetBitContext *gb = &s->gb;
108  unsigned code = svq3_get_ue_golomb(gb);
109 
110  if (code > 11) {
111  av_log(s->avctx, AV_LOG_ERROR, "Incorrect MB type code\n");
112  return -1;
113  }
114  if(code > 5){
115  av_log(s->avctx, AV_LOG_ERROR, "dquant needed\n");
116  code -= 6;
117  }
118  if(s->pict_type != AV_PICTURE_TYPE_B)
119  return rv30_p_types[code];
120  else
121  return rv30_b_types[code];
122 }
123 
124 static inline void rv30_weak_loop_filter(uint8_t *src, const int step,
125  const int stride, const int lim)
126 {
128  int i, diff;
129 
130  for(i = 0; i < 4; i++){
131  diff = ((src[-2*step] - src[1*step]) - (src[-1*step] - src[0*step])*4) >> 3;
132  diff = av_clip(diff, -lim, lim);
133  src[-1*step] = cm[src[-1*step] + diff];
134  src[ 0*step] = cm[src[ 0*step] - diff];
135  src += stride;
136  }
137 }
138 
139 static void rv30_loop_filter(RV34DecContext *r, int row)
140 {
141  MpegEncContext *s = &r->s;
142  int mb_pos, mb_x;
143  int i, j, k;
144  uint8_t *Y, *C;
145  int loc_lim, cur_lim, left_lim = 0, top_lim = 0;
146 
147  mb_pos = row * s->mb_stride;
148  for(mb_x = 0; mb_x < s->mb_width; mb_x++, mb_pos++){
149  int mbtype = s->current_picture_ptr->f.mb_type[mb_pos];
150  if(IS_INTRA(mbtype) || IS_SEPARATE_DC(mbtype))
151  r->deblock_coefs[mb_pos] = 0xFFFF;
152  if(IS_INTRA(mbtype))
153  r->cbp_chroma[mb_pos] = 0xFF;
154  }
155 
156  /* all vertical edges are filtered first
157  * and horizontal edges are filtered on the next iteration
158  */
159  mb_pos = row * s->mb_stride;
160  for(mb_x = 0; mb_x < s->mb_width; mb_x++, mb_pos++){
161  cur_lim = rv30_loop_filt_lim[s->current_picture_ptr->f.qscale_table[mb_pos]];
162  if(mb_x)
163  left_lim = rv30_loop_filt_lim[s->current_picture_ptr->f.qscale_table[mb_pos - 1]];
164  for(j = 0; j < 16; j += 4){
165  Y = s->current_picture_ptr->f.data[0] + mb_x*16 + (row*16 + j) * s->linesize + 4 * !mb_x;
166  for(i = !mb_x; i < 4; i++, Y += 4){
167  int ij = i + j;
168  loc_lim = 0;
169  if(r->deblock_coefs[mb_pos] & (1 << ij))
170  loc_lim = cur_lim;
171  else if(!i && r->deblock_coefs[mb_pos - 1] & (1 << (ij + 3)))
172  loc_lim = left_lim;
173  else if( i && r->deblock_coefs[mb_pos] & (1 << (ij - 1)))
174  loc_lim = cur_lim;
175  if(loc_lim)
176  rv30_weak_loop_filter(Y, 1, s->linesize, loc_lim);
177  }
178  }
179  for(k = 0; k < 2; k++){
180  int cur_cbp, left_cbp = 0;
181  cur_cbp = (r->cbp_chroma[mb_pos] >> (k*4)) & 0xF;
182  if(mb_x)
183  left_cbp = (r->cbp_chroma[mb_pos - 1] >> (k*4)) & 0xF;
184  for(j = 0; j < 8; j += 4){
185  C = s->current_picture_ptr->f.data[k + 1] + mb_x*8 + (row*8 + j) * s->uvlinesize + 4 * !mb_x;
186  for(i = !mb_x; i < 2; i++, C += 4){
187  int ij = i + (j >> 1);
188  loc_lim = 0;
189  if (cur_cbp & (1 << ij))
190  loc_lim = cur_lim;
191  else if(!i && left_cbp & (1 << (ij + 1)))
192  loc_lim = left_lim;
193  else if( i && cur_cbp & (1 << (ij - 1)))
194  loc_lim = cur_lim;
195  if(loc_lim)
196  rv30_weak_loop_filter(C, 1, s->uvlinesize, loc_lim);
197  }
198  }
199  }
200  }
201  mb_pos = row * s->mb_stride;
202  for(mb_x = 0; mb_x < s->mb_width; mb_x++, mb_pos++){
203  cur_lim = rv30_loop_filt_lim[s->current_picture_ptr->f.qscale_table[mb_pos]];
204  if(row)
205  top_lim = rv30_loop_filt_lim[s->current_picture_ptr->f.qscale_table[mb_pos - s->mb_stride]];
206  for(j = 4*!row; j < 16; j += 4){
207  Y = s->current_picture_ptr->f.data[0] + mb_x*16 + (row*16 + j) * s->linesize;
208  for(i = 0; i < 4; i++, Y += 4){
209  int ij = i + j;
210  loc_lim = 0;
211  if(r->deblock_coefs[mb_pos] & (1 << ij))
212  loc_lim = cur_lim;
213  else if(!j && r->deblock_coefs[mb_pos - s->mb_stride] & (1 << (ij + 12)))
214  loc_lim = top_lim;
215  else if( j && r->deblock_coefs[mb_pos] & (1 << (ij - 4)))
216  loc_lim = cur_lim;
217  if(loc_lim)
218  rv30_weak_loop_filter(Y, s->linesize, 1, loc_lim);
219  }
220  }
221  for(k = 0; k < 2; k++){
222  int cur_cbp, top_cbp = 0;
223  cur_cbp = (r->cbp_chroma[mb_pos] >> (k*4)) & 0xF;
224  if(row)
225  top_cbp = (r->cbp_chroma[mb_pos - s->mb_stride] >> (k*4)) & 0xF;
226  for(j = 4*!row; j < 8; j += 4){
227  C = s->current_picture_ptr->f.data[k+1] + mb_x*8 + (row*8 + j) * s->uvlinesize;
228  for(i = 0; i < 2; i++, C += 4){
229  int ij = i + (j >> 1);
230  loc_lim = 0;
231  if (r->cbp_chroma[mb_pos] & (1 << ij))
232  loc_lim = cur_lim;
233  else if(!j && top_cbp & (1 << (ij + 2)))
234  loc_lim = top_lim;
235  else if( j && cur_cbp & (1 << (ij - 2)))
236  loc_lim = cur_lim;
237  if(loc_lim)
238  rv30_weak_loop_filter(C, s->uvlinesize, 1, loc_lim);
239  }
240  }
241  }
242  }
243 }
244 
245 /**
246  * Initialize decoder.
247  */
249 {
250  RV34DecContext *r = avctx->priv_data;
251 
252  r->rv30 = 1;
253  ff_rv34_decode_init(avctx);
254  if(avctx->extradata_size < 2){
255  av_log(avctx, AV_LOG_ERROR, "Extradata is too small.\n");
256  return -1;
257  }
258  r->rpr = (avctx->extradata[1] & 7) >> 1;
259  r->rpr = FFMIN(r->rpr + 1, 3);
260  if(avctx->extradata_size - 8 < (r->rpr - 1) * 2){
261  av_log(avctx, AV_LOG_ERROR, "Insufficient extradata - need at least %d bytes, got %d\n",
262  6 + r->rpr * 2, avctx->extradata_size);
263  }
270  return 0;
271 }
272 
274  .name = "rv30",
275  .type = AVMEDIA_TYPE_VIDEO,
276  .id = AV_CODEC_ID_RV30,
277  .priv_data_size = sizeof(RV34DecContext),
281  .capabilities = CODEC_CAP_DR1 | CODEC_CAP_DELAY |
283  .flush = ff_mpeg_flush,
284  .long_name = NULL_IF_CONFIG_SMALL("RealVideo 3.0"),
285  .pix_fmts = ff_pixfmt_list_420,
288 };