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asvdec.c
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1 /*
2  * Copyright (c) 2003 Michael Niedermayer
3  *
4  * This file is part of FFmpeg.
5  *
6  * FFmpeg 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  * FFmpeg 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 FFmpeg; if not, write to the Free Software
18  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
19  */
20 
21 /**
22  * @file
23  * ASUS V1/V2 decoder.
24  */
25 
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 "dsputil.h"
33 #include "internal.h"
34 #include "mathops.h"
35 #include "mpeg12data.h"
36 
37 #define VLC_BITS 6
38 #define ASV2_LEVEL_VLC_BITS 10
39 
40 static VLC ccp_vlc;
41 static VLC level_vlc;
42 static VLC dc_ccp_vlc;
43 static VLC ac_ccp_vlc;
45 
47 {
48  static int done = 0;
49 
50  if (!done) {
51  done = 1;
52 
53  INIT_VLC_STATIC(&ccp_vlc, VLC_BITS, 17,
54  &ff_asv_ccp_tab[0][1], 2, 1,
55  &ff_asv_ccp_tab[0][0], 2, 1, 64);
56  INIT_VLC_STATIC(&dc_ccp_vlc, VLC_BITS, 8,
57  &ff_asv_dc_ccp_tab[0][1], 2, 1,
58  &ff_asv_dc_ccp_tab[0][0], 2, 1, 64);
59  INIT_VLC_STATIC(&ac_ccp_vlc, VLC_BITS, 16,
60  &ff_asv_ac_ccp_tab[0][1], 2, 1,
61  &ff_asv_ac_ccp_tab[0][0], 2, 1, 64);
62  INIT_VLC_STATIC(&level_vlc, VLC_BITS, 7,
63  &ff_asv_level_tab[0][1], 2, 1,
64  &ff_asv_level_tab[0][0], 2, 1, 64);
65  INIT_VLC_STATIC(&asv2_level_vlc, ASV2_LEVEL_VLC_BITS, 63,
66  &ff_asv2_level_tab[0][1], 2, 1,
67  &ff_asv2_level_tab[0][0], 2, 1, 1024);
68  }
69 }
70 
71 //FIXME write a reversed bitstream reader to avoid the double reverse
72 static inline int asv2_get_bits(GetBitContext *gb, int n)
73 {
74  return ff_reverse[get_bits(gb, n) << (8-n)];
75 }
76 
77 static inline int asv1_get_level(GetBitContext *gb)
78 {
79  int code = get_vlc2(gb, level_vlc.table, VLC_BITS, 1);
80 
81  if (code == 3)
82  return get_sbits(gb, 8);
83  else
84  return code - 3;
85 }
86 
87 static inline int asv2_get_level(GetBitContext *gb)
88 {
89  int code = get_vlc2(gb, asv2_level_vlc.table, ASV2_LEVEL_VLC_BITS, 1);
90 
91  if (code == 31)
92  return (int8_t)asv2_get_bits(gb, 8);
93  else
94  return code - 31;
95 }
96 
97 static inline int asv1_decode_block(ASV1Context *a, DCTELEM block[64])
98 {
99  int i;
100 
101  block[0] = 8 * get_bits(&a->gb, 8);
102 
103  for (i = 0; i < 11; i++) {
104  const int ccp = get_vlc2(&a->gb, ccp_vlc.table, VLC_BITS, 1);
105 
106  if (ccp) {
107  if (ccp == 16)
108  break;
109  if (ccp < 0 || i >= 10) {
110  av_log(a->avctx, AV_LOG_ERROR, "coded coeff pattern damaged\n");
111  return -1;
112  }
113 
114  if (ccp & 8)
115  block[a->scantable.permutated[4 * i + 0]] = (asv1_get_level(&a->gb) * a->intra_matrix[4 * i + 0]) >> 4;
116  if (ccp & 4)
117  block[a->scantable.permutated[4 * i + 1]] = (asv1_get_level(&a->gb) * a->intra_matrix[4 * i + 1]) >> 4;
118  if (ccp & 2)
119  block[a->scantable.permutated[4 * i + 2]] = (asv1_get_level(&a->gb) * a->intra_matrix[4 * i + 2]) >> 4;
120  if (ccp & 1)
121  block[a->scantable.permutated[4 * i + 3]] = (asv1_get_level(&a->gb) * a->intra_matrix[4 * i + 3]) >> 4;
122  }
123  }
124 
125  return 0;
126 }
127 
128 static inline int asv2_decode_block(ASV1Context *a, DCTELEM block[64])
129 {
130  int i, count, ccp;
131 
132  count = asv2_get_bits(&a->gb, 4);
133 
134  block[0] = 8 * asv2_get_bits(&a->gb, 8);
135 
136  ccp = get_vlc2(&a->gb, dc_ccp_vlc.table, VLC_BITS, 1);
137  if (ccp) {
138  if (ccp & 4)
139  block[a->scantable.permutated[1]] = (asv2_get_level(&a->gb) * a->intra_matrix[1]) >> 4;
140  if (ccp & 2)
141  block[a->scantable.permutated[2]] = (asv2_get_level(&a->gb) * a->intra_matrix[2]) >> 4;
142  if (ccp & 1)
143  block[a->scantable.permutated[3]] = (asv2_get_level(&a->gb) * a->intra_matrix[3]) >> 4;
144  }
145 
146  for (i = 1; i < count + 1; i++) {
147  const int ccp = get_vlc2(&a->gb, ac_ccp_vlc.table, VLC_BITS, 1);
148 
149  if (ccp) {
150  if (ccp & 8)
151  block[a->scantable.permutated[4*i + 0]] = (asv2_get_level(&a->gb) * a->intra_matrix[4*i + 0]) >> 4;
152  if (ccp & 4)
153  block[a->scantable.permutated[4*i + 1]] = (asv2_get_level(&a->gb) * a->intra_matrix[4*i + 1]) >> 4;
154  if (ccp & 2)
155  block[a->scantable.permutated[4*i + 2]] = (asv2_get_level(&a->gb) * a->intra_matrix[4*i + 2]) >> 4;
156  if (ccp & 1)
157  block[a->scantable.permutated[4*i + 3]] = (asv2_get_level(&a->gb) * a->intra_matrix[4*i + 3]) >> 4;
158  }
159  }
160 
161  return 0;
162 }
163 
164 static inline int decode_mb(ASV1Context *a, DCTELEM block[6][64])
165 {
166  int i;
167 
168  a->dsp.clear_blocks(block[0]);
169 
170  if (a->avctx->codec_id == AV_CODEC_ID_ASV1) {
171  for (i = 0; i < 6; i++) {
172  if (asv1_decode_block(a, block[i]) < 0)
173  return -1;
174  }
175  } else {
176  for (i = 0; i < 6; i++) {
177  if (asv2_decode_block(a, block[i]) < 0)
178  return -1;
179  }
180  }
181  return 0;
182 }
183 
184 static inline void idct_put(ASV1Context *a, int mb_x, int mb_y)
185 {
186  DCTELEM (*block)[64] = a->block;
187  int linesize = a->picture.linesize[0];
188 
189  uint8_t *dest_y = a->picture.data[0] + (mb_y * 16* linesize ) + mb_x * 16;
190  uint8_t *dest_cb = a->picture.data[1] + (mb_y * 8 * a->picture.linesize[1]) + mb_x * 8;
191  uint8_t *dest_cr = a->picture.data[2] + (mb_y * 8 * a->picture.linesize[2]) + mb_x * 8;
192 
193  a->dsp.idct_put(dest_y , linesize, block[0]);
194  a->dsp.idct_put(dest_y + 8, linesize, block[1]);
195  a->dsp.idct_put(dest_y + 8*linesize , linesize, block[2]);
196  a->dsp.idct_put(dest_y + 8*linesize + 8, linesize, block[3]);
197 
198  if (!(a->avctx->flags&CODEC_FLAG_GRAY)) {
199  a->dsp.idct_put(dest_cb, a->picture.linesize[1], block[4]);
200  a->dsp.idct_put(dest_cr, a->picture.linesize[2], block[5]);
201  }
202 }
203 
204 static int decode_frame(AVCodecContext *avctx,
205  void *data, int *got_frame,
206  AVPacket *avpkt)
207 {
208  ASV1Context * const a = avctx->priv_data;
209  const uint8_t *buf = avpkt->data;
210  int buf_size = avpkt->size;
211  AVFrame *picture = data;
212  AVFrame * const p = &a->picture;
213  int mb_x, mb_y;
214 
215  if (p->data[0])
216  avctx->release_buffer(avctx, p);
217 
218  p->reference = 0;
219  if (ff_get_buffer(avctx, p) < 0) {
220  av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
221  return -1;
222  }
224  p->key_frame = 1;
225 
227  buf_size);
228  if (!a->bitstream_buffer)
229  return AVERROR(ENOMEM);
230 
231  if (avctx->codec_id == AV_CODEC_ID_ASV1)
232  a->dsp.bswap_buf((uint32_t*)a->bitstream_buffer, (const uint32_t*)buf, buf_size/4);
233  else {
234  int i;
235  for (i = 0; i < buf_size; i++)
236  a->bitstream_buffer[i] = ff_reverse[buf[i]];
237  }
238 
239  init_get_bits(&a->gb, a->bitstream_buffer, buf_size*8);
240 
241  for (mb_y = 0; mb_y < a->mb_height2; mb_y++) {
242  for (mb_x = 0; mb_x < a->mb_width2; mb_x++) {
243  if (decode_mb(a, a->block) < 0)
244  return -1;
245 
246  idct_put(a, mb_x, mb_y);
247  }
248  }
249 
250  if (a->mb_width2 != a->mb_width) {
251  mb_x = a->mb_width2;
252  for (mb_y = 0; mb_y < a->mb_height2; mb_y++) {
253  if (decode_mb(a, a->block) < 0)
254  return -1;
255 
256  idct_put(a, mb_x, mb_y);
257  }
258  }
259 
260  if (a->mb_height2 != a->mb_height) {
261  mb_y = a->mb_height2;
262  for (mb_x = 0; mb_x < a->mb_width; mb_x++) {
263  if (decode_mb(a, a->block) < 0)
264  return -1;
265 
266  idct_put(a, mb_x, mb_y);
267  }
268  }
269 
270  *picture = a->picture;
271  *got_frame = 1;
272 
273  emms_c();
274 
275  return (get_bits_count(&a->gb) + 31) / 32 * 4;
276 }
277 
279 {
280  ASV1Context * const a = avctx->priv_data;
281  AVFrame *p = &a->picture;
282  const int scale = avctx->codec_id == AV_CODEC_ID_ASV1 ? 1 : 2;
283  int i;
284 
285  ff_asv_common_init(avctx);
286  init_vlcs(a);
288  avctx->pix_fmt = AV_PIX_FMT_YUV420P;
289 
290  if (avctx->extradata_size < 1 || (a->inv_qscale = avctx->extradata[0]) == 0) {
291  av_log(avctx, AV_LOG_ERROR, "illegal qscale 0\n");
292  if (avctx->codec_id == AV_CODEC_ID_ASV1)
293  a->inv_qscale = 6;
294  else
295  a->inv_qscale = 10;
296  }
297 
298  for (i = 0; i < 64; i++) {
299  int index = ff_asv_scantab[i];
300 
301  a->intra_matrix[i] = 64 * scale * ff_mpeg1_default_intra_matrix[index] / a->inv_qscale;
302  }
303 
304  p->qstride = a->mb_width;
305  p->qscale_table = av_malloc(p->qstride * a->mb_height);
306  p->quality = (32 * scale + a->inv_qscale / 2) / a->inv_qscale;
307  memset(p->qscale_table, p->quality, p->qstride * a->mb_height);
308 
309  return 0;
310 }
311 
313 {
314  ASV1Context * const a = avctx->priv_data;
315 
318  a->bitstream_buffer_size = 0;
319 
320  if (a->picture.data[0])
321  avctx->release_buffer(avctx, &a->picture);
322 
323  return 0;
324 }
325 
326 #if CONFIG_ASV1_DECODER
327 AVCodec ff_asv1_decoder = {
328  .name = "asv1",
329  .type = AVMEDIA_TYPE_VIDEO,
330  .id = AV_CODEC_ID_ASV1,
331  .priv_data_size = sizeof(ASV1Context),
332  .init = decode_init,
333  .close = decode_end,
334  .decode = decode_frame,
335  .capabilities = CODEC_CAP_DR1,
336  .long_name = NULL_IF_CONFIG_SMALL("ASUS V1"),
337 };
338 #endif
339 
340 #if CONFIG_ASV2_DECODER
341 AVCodec ff_asv2_decoder = {
342  .name = "asv2",
343  .type = AVMEDIA_TYPE_VIDEO,
344  .id = AV_CODEC_ID_ASV2,
345  .priv_data_size = sizeof(ASV1Context),
346  .init = decode_init,
347  .close = decode_end,
348  .decode = decode_frame,
349  .capabilities = CODEC_CAP_DR1,
350  .long_name = NULL_IF_CONFIG_SMALL("ASUS V2"),
351 };
352 #endif
353