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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 "mpegutils.h"
29 #include "mpegvideo.h"
30 #include "golomb.h"
31 
32 #include "rv34.h"
33 #include "rv30data.h"
34 
35 
37 {
38  AVCodecContext *avctx = r->s.avctx;
39  int mb_bits;
40  int w = r->s.width, h = r->s.height;
41  int mb_size;
42  int rpr;
43 
44  memset(si, 0, sizeof(SliceInfo));
45  if(get_bits(gb, 3))
46  return -1;
47  si->type = get_bits(gb, 2);
48  if(si->type == 1) si->type = 0;
49  if(get_bits1(gb))
50  return -1;
51  si->quant = get_bits(gb, 5);
52  skip_bits1(gb);
53  si->pts = get_bits(gb, 13);
54  rpr = get_bits(gb, av_log2(r->max_rpr) + 1);
55  if(rpr){
56  if (rpr > r->max_rpr) {
57  av_log(avctx, AV_LOG_ERROR, "rpr too large\n");
58  return AVERROR_INVALIDDATA;
59  }
60 
61  if (avctx->extradata_size < rpr * 2 + 8) {
62  av_log(avctx, AV_LOG_ERROR,
63  "Insufficient extradata - need at least %d bytes, got %d\n",
64  8 + rpr * 2, avctx->extradata_size);
65  return AVERROR(EINVAL);
66  }
67 
68  w = r->s.avctx->extradata[6 + rpr*2] << 2;
69  h = r->s.avctx->extradata[7 + rpr*2] << 2;
70  }
71  si->width = w;
72  si->height = h;
73  mb_size = ((w + 15) >> 4) * ((h + 15) >> 4);
74  mb_bits = ff_rv34_get_start_offset(gb, mb_size);
75  si->start = get_bits(gb, mb_bits);
76  skip_bits1(gb);
77  return 0;
78 }
79 
80 /**
81  * Decode 4x4 intra types array.
82  */
83 static int rv30_decode_intra_types(RV34DecContext *r, GetBitContext *gb, int8_t *dst)
84 {
85  int i, j, k;
86 
87  for(i = 0; i < 4; i++, dst += r->intra_types_stride - 4){
88  for(j = 0; j < 4; j+= 2){
89  unsigned code = svq3_get_ue_golomb(gb) << 1;
90  if (code > 80U*2U) {
91  av_log(r->s.avctx, AV_LOG_ERROR, "Incorrect intra prediction code\n");
92  return -1;
93  }
94  for(k = 0; k < 2; k++){
95  int A = dst[-r->intra_types_stride] + 1;
96  int B = dst[-1] + 1;
97  *dst++ = rv30_itype_from_context[A * 90 + B * 9 + rv30_itype_code[code + k]];
98  if(dst[-1] == 9){
99  av_log(r->s.avctx, AV_LOG_ERROR, "Incorrect intra prediction mode\n");
100  return -1;
101  }
102  }
103  }
104  }
105  return 0;
106 }
107 
108 /**
109  * Decode macroblock information.
110  */
112 {
113  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 };
115  MpegEncContext *s = &r->s;
116  GetBitContext *gb = &s->gb;
117  unsigned code = svq3_get_ue_golomb(gb);
118 
119  if (code > 11) {
120  av_log(s->avctx, AV_LOG_ERROR, "Incorrect MB type code\n");
121  return -1;
122  }
123  if(code > 5){
124  av_log(s->avctx, AV_LOG_ERROR, "dquant needed\n");
125  code -= 6;
126  }
127  if(s->pict_type != AV_PICTURE_TYPE_B)
128  return rv30_p_types[code];
129  else
130  return rv30_b_types[code];
131 }
132 
133 static inline void rv30_weak_loop_filter(uint8_t *src, const int step,
134  const int stride, const int lim)
135 {
136  const uint8_t *cm = ff_crop_tab + MAX_NEG_CROP;
137  int i, diff;
138 
139  for(i = 0; i < 4; i++){
140  diff = ((src[-2*step] - src[1*step]) - (src[-1*step] - src[0*step])*4) >> 3;
141  diff = av_clip(diff, -lim, lim);
142  src[-1*step] = cm[src[-1*step] + diff];
143  src[ 0*step] = cm[src[ 0*step] - diff];
144  src += stride;
145  }
146 }
147 
148 static void rv30_loop_filter(RV34DecContext *r, int row)
149 {
150  MpegEncContext *s = &r->s;
151  int mb_pos, mb_x;
152  int i, j, k;
153  uint8_t *Y, *C;
154  int loc_lim, cur_lim, left_lim = 0, top_lim = 0;
155 
156  mb_pos = row * s->mb_stride;
157  for(mb_x = 0; mb_x < s->mb_width; mb_x++, mb_pos++){
158  int mbtype = s->current_picture_ptr->mb_type[mb_pos];
159  if(IS_INTRA(mbtype) || IS_SEPARATE_DC(mbtype))
160  r->deblock_coefs[mb_pos] = 0xFFFF;
161  if(IS_INTRA(mbtype))
162  r->cbp_chroma[mb_pos] = 0xFF;
163  }
164 
165  /* all vertical edges are filtered first
166  * and horizontal edges are filtered on the next iteration
167  */
168  mb_pos = row * s->mb_stride;
169  for(mb_x = 0; mb_x < s->mb_width; mb_x++, mb_pos++){
170  cur_lim = rv30_loop_filt_lim[s->current_picture_ptr->qscale_table[mb_pos]];
171  if(mb_x)
172  left_lim = rv30_loop_filt_lim[s->current_picture_ptr->qscale_table[mb_pos - 1]];
173  for(j = 0; j < 16; j += 4){
174  Y = s->current_picture_ptr->f->data[0] + mb_x*16 + (row*16 + j) * s->linesize + 4 * !mb_x;
175  for(i = !mb_x; i < 4; i++, Y += 4){
176  int ij = i + j;
177  loc_lim = 0;
178  if(r->deblock_coefs[mb_pos] & (1 << ij))
179  loc_lim = cur_lim;
180  else if(!i && r->deblock_coefs[mb_pos - 1] & (1 << (ij + 3)))
181  loc_lim = left_lim;
182  else if( i && r->deblock_coefs[mb_pos] & (1 << (ij - 1)))
183  loc_lim = cur_lim;
184  if(loc_lim)
185  rv30_weak_loop_filter(Y, 1, s->linesize, loc_lim);
186  }
187  }
188  for(k = 0; k < 2; k++){
189  int cur_cbp, left_cbp = 0;
190  cur_cbp = (r->cbp_chroma[mb_pos] >> (k*4)) & 0xF;
191  if(mb_x)
192  left_cbp = (r->cbp_chroma[mb_pos - 1] >> (k*4)) & 0xF;
193  for(j = 0; j < 8; j += 4){
194  C = s->current_picture_ptr->f->data[k + 1] + mb_x*8 + (row*8 + j) * s->uvlinesize + 4 * !mb_x;
195  for(i = !mb_x; i < 2; i++, C += 4){
196  int ij = i + (j >> 1);
197  loc_lim = 0;
198  if (cur_cbp & (1 << ij))
199  loc_lim = cur_lim;
200  else if(!i && left_cbp & (1 << (ij + 1)))
201  loc_lim = left_lim;
202  else if( i && cur_cbp & (1 << (ij - 1)))
203  loc_lim = cur_lim;
204  if(loc_lim)
205  rv30_weak_loop_filter(C, 1, s->uvlinesize, loc_lim);
206  }
207  }
208  }
209  }
210  mb_pos = row * s->mb_stride;
211  for(mb_x = 0; mb_x < s->mb_width; mb_x++, mb_pos++){
212  cur_lim = rv30_loop_filt_lim[s->current_picture_ptr->qscale_table[mb_pos]];
213  if(row)
214  top_lim = rv30_loop_filt_lim[s->current_picture_ptr->qscale_table[mb_pos - s->mb_stride]];
215  for(j = 4*!row; j < 16; j += 4){
216  Y = s->current_picture_ptr->f->data[0] + mb_x*16 + (row*16 + j) * s->linesize;
217  for(i = 0; i < 4; i++, Y += 4){
218  int ij = i + j;
219  loc_lim = 0;
220  if(r->deblock_coefs[mb_pos] & (1 << ij))
221  loc_lim = cur_lim;
222  else if(!j && r->deblock_coefs[mb_pos - s->mb_stride] & (1 << (ij + 12)))
223  loc_lim = top_lim;
224  else if( j && r->deblock_coefs[mb_pos] & (1 << (ij - 4)))
225  loc_lim = cur_lim;
226  if(loc_lim)
227  rv30_weak_loop_filter(Y, s->linesize, 1, loc_lim);
228  }
229  }
230  for(k = 0; k < 2; k++){
231  int cur_cbp, top_cbp = 0;
232  cur_cbp = (r->cbp_chroma[mb_pos] >> (k*4)) & 0xF;
233  if(row)
234  top_cbp = (r->cbp_chroma[mb_pos - s->mb_stride] >> (k*4)) & 0xF;
235  for(j = 4*!row; j < 8; j += 4){
236  C = s->current_picture_ptr->f->data[k+1] + mb_x*8 + (row*8 + j) * s->uvlinesize;
237  for(i = 0; i < 2; i++, C += 4){
238  int ij = i + (j >> 1);
239  loc_lim = 0;
240  if (r->cbp_chroma[mb_pos] & (1 << ij))
241  loc_lim = cur_lim;
242  else if(!j && top_cbp & (1 << (ij + 2)))
243  loc_lim = top_lim;
244  else if( j && cur_cbp & (1 << (ij - 2)))
245  loc_lim = cur_lim;
246  if(loc_lim)
247  rv30_weak_loop_filter(C, s->uvlinesize, 1, loc_lim);
248  }
249  }
250  }
251  }
252 }
253 
254 /**
255  * Initialize decoder.
256  */
258 {
259  RV34DecContext *r = avctx->priv_data;
260  int ret;
261 
262  r->rv30 = 1;
263  if ((ret = ff_rv34_decode_init(avctx)) < 0)
264  return ret;
265  if(avctx->extradata_size < 2){
266  av_log(avctx, AV_LOG_ERROR, "Extradata is too small.\n");
267  return -1;
268  }
269 
270  r->max_rpr = avctx->extradata[1] & 7;
271  if(avctx->extradata_size < 2*r->max_rpr + 8){
272  av_log(avctx, AV_LOG_WARNING, "Insufficient extradata - need at least %d bytes, got %d\n",
273  2*r->max_rpr + 8, avctx->extradata_size);
274  }
275 
282  return 0;
283 }
284 
286  .name = "rv30",
287  .long_name = NULL_IF_CONFIG_SMALL("RealVideo 3.0"),
288  .type = AVMEDIA_TYPE_VIDEO,
289  .id = AV_CODEC_ID_RV30,
290  .priv_data_size = sizeof(RV34DecContext),
294  .capabilities = CODEC_CAP_DR1 | CODEC_CAP_DELAY |
296  .flush = ff_mpeg_flush,
297  .pix_fmts = (const enum AVPixelFormat[]) {
300  },
303 };