Libav
asvdec.c
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1 /*
2  * Copyright (c) 2003 Michael Niedermayer
3  *
4  * This file is part of Libav.
5  *
6  * Libav is free software; you can redistribute it and/or
7  * modify it under the terms of the GNU Lesser General Public
8  * License as published by the Free Software Foundation; either
9  * version 2.1 of the License, or (at your option) any later version.
10  *
11  * Libav is distributed in the hope that it will be useful,
12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14  * Lesser General Public License for more details.
15  *
16  * You should have received a copy of the GNU Lesser General Public
17  * License along with Libav; if not, write to the Free Software
18  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
19  */
20 
26 #include "libavutil/attributes.h"
27 #include "libavutil/mem.h"
28 
29 #include "asv.h"
30 #include "avcodec.h"
31 #include "put_bits.h"
32 #include "internal.h"
33 #include "mathops.h"
34 #include "mpeg12data.h"
35 
36 #define VLC_BITS 6
37 #define ASV2_LEVEL_VLC_BITS 10
38 
39 static VLC ccp_vlc;
40 static VLC level_vlc;
41 static VLC dc_ccp_vlc;
42 static VLC ac_ccp_vlc;
44 
45 static av_cold void init_vlcs(ASV1Context *a)
46 {
47  static int done = 0;
48 
49  if (!done) {
50  done = 1;
51 
52  INIT_VLC_STATIC(&ccp_vlc, VLC_BITS, 17,
53  &ff_asv_ccp_tab[0][1], 2, 1,
54  &ff_asv_ccp_tab[0][0], 2, 1, 64);
55  INIT_VLC_STATIC(&dc_ccp_vlc, VLC_BITS, 8,
56  &ff_asv_dc_ccp_tab[0][1], 2, 1,
57  &ff_asv_dc_ccp_tab[0][0], 2, 1, 64);
58  INIT_VLC_STATIC(&ac_ccp_vlc, VLC_BITS, 16,
59  &ff_asv_ac_ccp_tab[0][1], 2, 1,
60  &ff_asv_ac_ccp_tab[0][0], 2, 1, 64);
61  INIT_VLC_STATIC(&level_vlc, VLC_BITS, 7,
62  &ff_asv_level_tab[0][1], 2, 1,
63  &ff_asv_level_tab[0][0], 2, 1, 64);
64  INIT_VLC_STATIC(&asv2_level_vlc, ASV2_LEVEL_VLC_BITS, 63,
65  &ff_asv2_level_tab[0][1], 2, 1,
66  &ff_asv2_level_tab[0][0], 2, 1, 1024);
67  }
68 }
69 
70 //FIXME write a reversed bitstream reader to avoid the double reverse
71 static inline int asv2_get_bits(GetBitContext *gb, int n)
72 {
73  return ff_reverse[get_bits(gb, n) << (8-n)];
74 }
75 
76 static inline int asv1_get_level(GetBitContext *gb)
77 {
78  int code = get_vlc2(gb, level_vlc.table, VLC_BITS, 1);
79 
80  if (code == 3)
81  return get_sbits(gb, 8);
82  else
83  return code - 3;
84 }
85 
86 static inline int asv2_get_level(GetBitContext *gb)
87 {
88  int code = get_vlc2(gb, asv2_level_vlc.table, ASV2_LEVEL_VLC_BITS, 1);
89 
90  if (code == 31)
91  return (int8_t)asv2_get_bits(gb, 8);
92  else
93  return code - 31;
94 }
95 
96 static inline int asv1_decode_block(ASV1Context *a, int16_t block[64])
97 {
98  int i;
99 
100  block[0] = 8 * get_bits(&a->gb, 8);
101 
102  for (i = 0; i < 11; i++) {
103  const int ccp = get_vlc2(&a->gb, ccp_vlc.table, VLC_BITS, 1);
104 
105  if (ccp) {
106  if (ccp == 16)
107  break;
108  if (ccp < 0 || i >= 10) {
109  av_log(a->avctx, AV_LOG_ERROR, "coded coeff pattern damaged\n");
110  return AVERROR_INVALIDDATA;
111  }
112 
113  if (ccp & 8)
114  block[a->scantable.permutated[4 * i + 0]] = (asv1_get_level(&a->gb) * a->intra_matrix[4 * i + 0]) >> 4;
115  if (ccp & 4)
116  block[a->scantable.permutated[4 * i + 1]] = (asv1_get_level(&a->gb) * a->intra_matrix[4 * i + 1]) >> 4;
117  if (ccp & 2)
118  block[a->scantable.permutated[4 * i + 2]] = (asv1_get_level(&a->gb) * a->intra_matrix[4 * i + 2]) >> 4;
119  if (ccp & 1)
120  block[a->scantable.permutated[4 * i + 3]] = (asv1_get_level(&a->gb) * a->intra_matrix[4 * i + 3]) >> 4;
121  }
122  }
123 
124  return 0;
125 }
126 
127 static inline int asv2_decode_block(ASV1Context *a, int16_t block[64])
128 {
129  int i, count, ccp;
130 
131  count = asv2_get_bits(&a->gb, 4);
132 
133  block[0] = 8 * asv2_get_bits(&a->gb, 8);
134 
135  ccp = get_vlc2(&a->gb, dc_ccp_vlc.table, VLC_BITS, 1);
136  if (ccp) {
137  if (ccp & 4)
138  block[a->scantable.permutated[1]] = (asv2_get_level(&a->gb) * a->intra_matrix[1]) >> 4;
139  if (ccp & 2)
140  block[a->scantable.permutated[2]] = (asv2_get_level(&a->gb) * a->intra_matrix[2]) >> 4;
141  if (ccp & 1)
142  block[a->scantable.permutated[3]] = (asv2_get_level(&a->gb) * a->intra_matrix[3]) >> 4;
143  }
144 
145  for (i = 1; i < count + 1; i++) {
146  const int ccp = get_vlc2(&a->gb, ac_ccp_vlc.table, VLC_BITS, 1);
147 
148  if (ccp) {
149  if (ccp & 8)
150  block[a->scantable.permutated[4*i + 0]] = (asv2_get_level(&a->gb) * a->intra_matrix[4*i + 0]) >> 4;
151  if (ccp & 4)
152  block[a->scantable.permutated[4*i + 1]] = (asv2_get_level(&a->gb) * a->intra_matrix[4*i + 1]) >> 4;
153  if (ccp & 2)
154  block[a->scantable.permutated[4*i + 2]] = (asv2_get_level(&a->gb) * a->intra_matrix[4*i + 2]) >> 4;
155  if (ccp & 1)
156  block[a->scantable.permutated[4*i + 3]] = (asv2_get_level(&a->gb) * a->intra_matrix[4*i + 3]) >> 4;
157  }
158  }
159 
160  return 0;
161 }
162 
163 static inline int decode_mb(ASV1Context *a, int16_t block[6][64])
164 {
165  int i;
166 
167  a->dsp.clear_blocks(block[0]);
168 
169  if (a->avctx->codec_id == AV_CODEC_ID_ASV1) {
170  for (i = 0; i < 6; i++) {
171  if (asv1_decode_block(a, block[i]) < 0)
172  return -1;
173  }
174  } else {
175  for (i = 0; i < 6; i++) {
176  if (asv2_decode_block(a, block[i]) < 0)
177  return -1;
178  }
179  }
180  return 0;
181 }
182 
183 static inline void idct_put(ASV1Context *a, AVFrame *frame, int mb_x, int mb_y)
184 {
185  int16_t (*block)[64] = a->block;
186  int linesize = frame->linesize[0];
187 
188  uint8_t *dest_y = frame->data[0] + (mb_y * 16* linesize ) + mb_x * 16;
189  uint8_t *dest_cb = frame->data[1] + (mb_y * 8 * frame->linesize[1]) + mb_x * 8;
190  uint8_t *dest_cr = frame->data[2] + (mb_y * 8 * frame->linesize[2]) + mb_x * 8;
191 
192  a->dsp.idct_put(dest_y , linesize, block[0]);
193  a->dsp.idct_put(dest_y + 8, linesize, block[1]);
194  a->dsp.idct_put(dest_y + 8*linesize , linesize, block[2]);
195  a->dsp.idct_put(dest_y + 8*linesize + 8, linesize, block[3]);
196 
197  if (!(a->avctx->flags&CODEC_FLAG_GRAY)) {
198  a->dsp.idct_put(dest_cb, frame->linesize[1], block[4]);
199  a->dsp.idct_put(dest_cr, frame->linesize[2], block[5]);
200  }
201 }
202 
203 static int decode_frame(AVCodecContext *avctx,
204  void *data, int *got_frame,
205  AVPacket *avpkt)
206 {
207  ASV1Context * const a = avctx->priv_data;
208  const uint8_t *buf = avpkt->data;
209  int buf_size = avpkt->size;
210  AVFrame * const p = data;
211  int mb_x, mb_y, ret;
212 
213  if ((ret = ff_get_buffer(avctx, p, 0)) < 0) {
214  av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
215  return ret;
216  }
218  p->key_frame = 1;
219 
221  buf_size);
222  if (!a->bitstream_buffer)
223  return AVERROR(ENOMEM);
224 
225  if (avctx->codec_id == AV_CODEC_ID_ASV1)
226  a->dsp.bswap_buf((uint32_t*)a->bitstream_buffer, (const uint32_t*)buf, buf_size/4);
227  else {
228  int i;
229  for (i = 0; i < buf_size; i++)
230  a->bitstream_buffer[i] = ff_reverse[buf[i]];
231  }
232 
233  init_get_bits(&a->gb, a->bitstream_buffer, buf_size*8);
234 
235  for (mb_y = 0; mb_y < a->mb_height2; mb_y++) {
236  for (mb_x = 0; mb_x < a->mb_width2; mb_x++) {
237  if ((ret = decode_mb(a, a->block)) < 0)
238  return ret;
239 
240  idct_put(a, p, mb_x, mb_y);
241  }
242  }
243 
244  if (a->mb_width2 != a->mb_width) {
245  mb_x = a->mb_width2;
246  for (mb_y = 0; mb_y < a->mb_height2; mb_y++) {
247  if ((ret = decode_mb(a, a->block)) < 0)
248  return ret;
249 
250  idct_put(a, p, mb_x, mb_y);
251  }
252  }
253 
254  if (a->mb_height2 != a->mb_height) {
255  mb_y = a->mb_height2;
256  for (mb_x = 0; mb_x < a->mb_width; mb_x++) {
257  if ((ret = decode_mb(a, a->block)) < 0)
258  return ret;
259 
260  idct_put(a, p, mb_x, mb_y);
261  }
262  }
263 
264  *got_frame = 1;
265 
266  emms_c();
267 
268  return (get_bits_count(&a->gb) + 31) / 32 * 4;
269 }
270 
272 {
273  ASV1Context * const a = avctx->priv_data;
274  const int scale = avctx->codec_id == AV_CODEC_ID_ASV1 ? 1 : 2;
275  int i;
276 
277  if (avctx->extradata_size < 1) {
278  av_log(avctx, AV_LOG_ERROR, "No extradata provided\n");
279  return AVERROR_INVALIDDATA;
280  }
281 
282  ff_asv_common_init(avctx);
283  init_vlcs(a);
285  avctx->pix_fmt = AV_PIX_FMT_YUV420P;
286 
287  a->inv_qscale = avctx->extradata[0];
288  if (a->inv_qscale == 0) {
289  av_log(avctx, AV_LOG_ERROR, "illegal qscale 0\n");
290  if (avctx->codec_id == AV_CODEC_ID_ASV1)
291  a->inv_qscale = 6;
292  else
293  a->inv_qscale = 10;
294  }
295 
296  for (i = 0; i < 64; i++) {
297  int index = ff_asv_scantab[i];
298 
299  a->intra_matrix[i] = 64 * scale * ff_mpeg1_default_intra_matrix[index] / a->inv_qscale;
300  }
301 
302  return 0;
303 }
304 
306 {
307  ASV1Context * const a = avctx->priv_data;
308 
310  a->bitstream_buffer_size = 0;
311 
312  return 0;
313 }
314 
316  .name = "asv1",
317  .long_name = NULL_IF_CONFIG_SMALL("ASUS V1"),
318  .type = AVMEDIA_TYPE_VIDEO,
319  .id = AV_CODEC_ID_ASV1,
320  .priv_data_size = sizeof(ASV1Context),
321  .init = decode_init,
322  .close = decode_end,
323  .decode = decode_frame,
324  .capabilities = CODEC_CAP_DR1,
325 };
326 
328  .name = "asv2",
329  .long_name = NULL_IF_CONFIG_SMALL("ASUS V2"),
330  .type = AVMEDIA_TYPE_VIDEO,
331  .id = AV_CODEC_ID_ASV2,
332  .priv_data_size = sizeof(ASV1Context),
333  .init = decode_init,
334  .close = decode_end,
335  .decode = decode_frame,
336  .capabilities = CODEC_CAP_DR1,
337 };
338