Libav
rv30.c
Go to the documentation of this file.
1 /*
2  * RV30 decoder
3  * Copyright (c) 2007 Konstantin Shishkov
4  *
5  * This file is part of Libav.
6  *
7  * Libav 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  * Libav 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 Libav; if not, write to the Free Software
19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20  */
21 
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  AVCodecContext *avctx = r->s.avctx;
38  int mb_bits;
39  int w = r->s.width, h = r->s.height;
40  int mb_size;
41  int rpr;
42 
43  memset(si, 0, sizeof(SliceInfo));
44  if(get_bits(gb, 3))
45  return -1;
46  si->type = get_bits(gb, 2);
47  if(si->type == 1) si->type = 0;
48  if(get_bits1(gb))
49  return -1;
50  si->quant = get_bits(gb, 5);
51  skip_bits1(gb);
52  si->pts = get_bits(gb, 13);
53  rpr = get_bits(gb, r->rpr);
54  if(rpr){
55  if (avctx->extradata_size < rpr * 2 + 8) {
56  av_log(avctx, AV_LOG_ERROR,
57  "Insufficient extradata - need at least %d bytes, got %d\n",
58  8 + rpr * 2, avctx->extradata_size);
59  return AVERROR(EINVAL);
60  }
61 
62  w = r->s.avctx->extradata[6 + rpr*2] << 2;
63  h = r->s.avctx->extradata[7 + rpr*2] << 2;
64  }
65  si->width = w;
66  si->height = h;
67  mb_size = ((w + 15) >> 4) * ((h + 15) >> 4);
68  mb_bits = ff_rv34_get_start_offset(gb, mb_size);
69  si->start = get_bits(gb, mb_bits);
70  skip_bits1(gb);
71  return 0;
72 }
73 
77 static int rv30_decode_intra_types(RV34DecContext *r, GetBitContext *gb, int8_t *dst)
78 {
79  int i, j, k;
80 
81  for(i = 0; i < 4; i++, dst += r->intra_types_stride - 4){
82  for(j = 0; j < 4; j+= 2){
83  unsigned code = svq3_get_ue_golomb(gb) << 1;
84  if(code >= 81*2){
85  av_log(r->s.avctx, AV_LOG_ERROR, "Incorrect intra prediction code\n");
86  return -1;
87  }
88  for(k = 0; k < 2; k++){
89  int A = dst[-r->intra_types_stride] + 1;
90  int B = dst[-1] + 1;
91  *dst++ = rv30_itype_from_context[A * 90 + B * 9 + rv30_itype_code[code + k]];
92  if(dst[-1] == 9){
93  av_log(r->s.avctx, AV_LOG_ERROR, "Incorrect intra prediction mode\n");
94  return -1;
95  }
96  }
97  }
98  }
99  return 0;
100 }
101 
106 {
107  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 };
109  MpegEncContext *s = &r->s;
110  GetBitContext *gb = &s->gb;
111  unsigned code = svq3_get_ue_golomb(gb);
112 
113  if (code > 11) {
114  av_log(s->avctx, AV_LOG_ERROR, "Incorrect MB type code\n");
115  return -1;
116  }
117  if(code > 5){
118  av_log(s->avctx, AV_LOG_ERROR, "dquant needed\n");
119  code -= 6;
120  }
121  if(s->pict_type != AV_PICTURE_TYPE_B)
122  return rv30_p_types[code];
123  else
124  return rv30_b_types[code];
125 }
126 
127 static inline void rv30_weak_loop_filter(uint8_t *src, const int step,
128  const int stride, const int lim)
129 {
130  const uint8_t *cm = ff_cropTbl + MAX_NEG_CROP;
131  int i, diff;
132 
133  for(i = 0; i < 4; i++){
134  diff = ((src[-2*step] - src[1*step]) - (src[-1*step] - src[0*step])*4) >> 3;
135  diff = av_clip(diff, -lim, lim);
136  src[-1*step] = cm[src[-1*step] + diff];
137  src[ 0*step] = cm[src[ 0*step] - diff];
138  src += stride;
139  }
140 }
141 
142 static void rv30_loop_filter(RV34DecContext *r, int row)
143 {
144  MpegEncContext *s = &r->s;
145  int mb_pos, mb_x;
146  int i, j, k;
147  uint8_t *Y, *C;
148  int loc_lim, cur_lim, left_lim = 0, top_lim = 0;
149 
150  mb_pos = row * s->mb_stride;
151  for(mb_x = 0; mb_x < s->mb_width; mb_x++, mb_pos++){
152  int mbtype = s->current_picture_ptr->mb_type[mb_pos];
153  if(IS_INTRA(mbtype) || IS_SEPARATE_DC(mbtype))
154  r->deblock_coefs[mb_pos] = 0xFFFF;
155  if(IS_INTRA(mbtype))
156  r->cbp_chroma[mb_pos] = 0xFF;
157  }
158 
159  /* all vertical edges are filtered first
160  * and horizontal edges are filtered on the next iteration
161  */
162  mb_pos = row * s->mb_stride;
163  for(mb_x = 0; mb_x < s->mb_width; mb_x++, mb_pos++){
164  cur_lim = rv30_loop_filt_lim[s->current_picture_ptr->qscale_table[mb_pos]];
165  if(mb_x)
166  left_lim = rv30_loop_filt_lim[s->current_picture_ptr->qscale_table[mb_pos - 1]];
167  for(j = 0; j < 16; j += 4){
168  Y = s->current_picture_ptr->f.data[0] + mb_x*16 + (row*16 + j) * s->linesize + 4 * !mb_x;
169  for(i = !mb_x; i < 4; i++, Y += 4){
170  int ij = i + j;
171  loc_lim = 0;
172  if(r->deblock_coefs[mb_pos] & (1 << ij))
173  loc_lim = cur_lim;
174  else if(!i && r->deblock_coefs[mb_pos - 1] & (1 << (ij + 3)))
175  loc_lim = left_lim;
176  else if( i && r->deblock_coefs[mb_pos] & (1 << (ij - 1)))
177  loc_lim = cur_lim;
178  if(loc_lim)
179  rv30_weak_loop_filter(Y, 1, s->linesize, loc_lim);
180  }
181  }
182  for(k = 0; k < 2; k++){
183  int cur_cbp, left_cbp = 0;
184  cur_cbp = (r->cbp_chroma[mb_pos] >> (k*4)) & 0xF;
185  if(mb_x)
186  left_cbp = (r->cbp_chroma[mb_pos - 1] >> (k*4)) & 0xF;
187  for(j = 0; j < 8; j += 4){
188  C = s->current_picture_ptr->f.data[k + 1] + mb_x*8 + (row*8 + j) * s->uvlinesize + 4 * !mb_x;
189  for(i = !mb_x; i < 2; i++, C += 4){
190  int ij = i + (j >> 1);
191  loc_lim = 0;
192  if (cur_cbp & (1 << ij))
193  loc_lim = cur_lim;
194  else if(!i && left_cbp & (1 << (ij + 1)))
195  loc_lim = left_lim;
196  else if( i && cur_cbp & (1 << (ij - 1)))
197  loc_lim = cur_lim;
198  if(loc_lim)
199  rv30_weak_loop_filter(C, 1, s->uvlinesize, loc_lim);
200  }
201  }
202  }
203  }
204  mb_pos = row * s->mb_stride;
205  for(mb_x = 0; mb_x < s->mb_width; mb_x++, mb_pos++){
206  cur_lim = rv30_loop_filt_lim[s->current_picture_ptr->qscale_table[mb_pos]];
207  if(row)
208  top_lim = rv30_loop_filt_lim[s->current_picture_ptr->qscale_table[mb_pos - s->mb_stride]];
209  for(j = 4*!row; j < 16; j += 4){
210  Y = s->current_picture_ptr->f.data[0] + mb_x*16 + (row*16 + j) * s->linesize;
211  for(i = 0; i < 4; i++, Y += 4){
212  int ij = i + j;
213  loc_lim = 0;
214  if(r->deblock_coefs[mb_pos] & (1 << ij))
215  loc_lim = cur_lim;
216  else if(!j && r->deblock_coefs[mb_pos - s->mb_stride] & (1 << (ij + 12)))
217  loc_lim = top_lim;
218  else if( j && r->deblock_coefs[mb_pos] & (1 << (ij - 4)))
219  loc_lim = cur_lim;
220  if(loc_lim)
221  rv30_weak_loop_filter(Y, s->linesize, 1, loc_lim);
222  }
223  }
224  for(k = 0; k < 2; k++){
225  int cur_cbp, top_cbp = 0;
226  cur_cbp = (r->cbp_chroma[mb_pos] >> (k*4)) & 0xF;
227  if(row)
228  top_cbp = (r->cbp_chroma[mb_pos - s->mb_stride] >> (k*4)) & 0xF;
229  for(j = 4*!row; j < 8; j += 4){
230  C = s->current_picture_ptr->f.data[k+1] + mb_x*8 + (row*8 + j) * s->uvlinesize;
231  for(i = 0; i < 2; i++, C += 4){
232  int ij = i + (j >> 1);
233  loc_lim = 0;
234  if (r->cbp_chroma[mb_pos] & (1 << ij))
235  loc_lim = cur_lim;
236  else if(!j && top_cbp & (1 << (ij + 2)))
237  loc_lim = top_lim;
238  else if( j && cur_cbp & (1 << (ij - 2)))
239  loc_lim = cur_lim;
240  if(loc_lim)
241  rv30_weak_loop_filter(C, s->uvlinesize, 1, loc_lim);
242  }
243  }
244  }
245  }
246 }
247 
252 {
253  RV34DecContext *r = avctx->priv_data;
254  int ret;
255 
256  r->rv30 = 1;
257  if ((ret = ff_rv34_decode_init(avctx)) < 0)
258  return ret;
259  if(avctx->extradata_size < 2){
260  av_log(avctx, AV_LOG_ERROR, "Extradata is too small.\n");
261  return -1;
262  }
263  r->rpr = (avctx->extradata[1] & 7) >> 1;
264  r->rpr = FFMIN(r->rpr + 1, 3);
265 
272  return 0;
273 }
274 
276  .name = "rv30",
277  .long_name = NULL_IF_CONFIG_SMALL("RealVideo 3.0"),
278  .type = AVMEDIA_TYPE_VIDEO,
279  .id = AV_CODEC_ID_RV30,
280  .priv_data_size = sizeof(RV34DecContext),
284  .capabilities = CODEC_CAP_DR1 | CODEC_CAP_DELAY |
286  .flush = ff_mpeg_flush,
287  .pix_fmts = ff_pixfmt_list_420,
290 };