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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 "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 
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, int mb_x, int mb_y)
184 {
185  int16_t (*block)[64] = a->block;
186  int linesize = a->picture.linesize[0];
187 
188  uint8_t *dest_y = a->picture.data[0] + (mb_y * 16* linesize ) + mb_x * 16;
189  uint8_t *dest_cb = a->picture.data[1] + (mb_y * 8 * a->picture.linesize[1]) + mb_x * 8;
190  uint8_t *dest_cr = a->picture.data[2] + (mb_y * 8 * a->picture.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, a->picture.linesize[1], block[4]);
199  a->dsp.idct_put(dest_cr, a->picture.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 *picture = data;
211  AVFrame * const p = &a->picture;
212  int mb_x, mb_y, ret;
213 
214  if (p->data[0])
215  avctx->release_buffer(avctx, p);
216 
217  p->reference = 0;
218  if ((ret = ff_get_buffer(avctx, p)) < 0) {
219  av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
220  return ret;
221  }
223  p->key_frame = 1;
224 
226  buf_size);
227  if (!a->bitstream_buffer)
228  return AVERROR(ENOMEM);
229 
230  if (avctx->codec_id == AV_CODEC_ID_ASV1)
231  a->dsp.bswap_buf((uint32_t*)a->bitstream_buffer, (const uint32_t*)buf, buf_size/4);
232  else {
233  int i;
234  for (i = 0; i < buf_size; i++)
235  a->bitstream_buffer[i] = ff_reverse[buf[i]];
236  }
237 
238  init_get_bits(&a->gb, a->bitstream_buffer, buf_size*8);
239 
240  for (mb_y = 0; mb_y < a->mb_height2; mb_y++) {
241  for (mb_x = 0; mb_x < a->mb_width2; mb_x++) {
242  if ((ret = decode_mb(a, a->block)) < 0)
243  return ret;
244 
245  idct_put(a, mb_x, mb_y);
246  }
247  }
248 
249  if (a->mb_width2 != a->mb_width) {
250  mb_x = a->mb_width2;
251  for (mb_y = 0; mb_y < a->mb_height2; mb_y++) {
252  if ((ret = decode_mb(a, a->block)) < 0)
253  return ret;
254 
255  idct_put(a, mb_x, mb_y);
256  }
257  }
258 
259  if (a->mb_height2 != a->mb_height) {
260  mb_y = a->mb_height2;
261  for (mb_x = 0; mb_x < a->mb_width; mb_x++) {
262  if ((ret = decode_mb(a, a->block)) < 0)
263  return ret;
264 
265  idct_put(a, mb_x, mb_y);
266  }
267  }
268 
269  *picture = a->picture;
270  *got_frame = 1;
271 
272  emms_c();
273 
274  return (get_bits_count(&a->gb) + 31) / 32 * 4;
275 }
276 
278 {
279  ASV1Context * const a = avctx->priv_data;
280  AVFrame *p = &a->picture;
281  const int scale = avctx->codec_id == AV_CODEC_ID_ASV1 ? 1 : 2;
282  int i;
283 
284  ff_asv_common_init(avctx);
285  init_vlcs(a);
287  avctx->pix_fmt = AV_PIX_FMT_YUV420P;
288 
289  if (avctx->extradata_size < 1 || (a->inv_qscale = avctx->extradata[0]) == 0) {
290  av_log(avctx, AV_LOG_ERROR, "illegal qscale 0\n");
291  if (avctx->codec_id == AV_CODEC_ID_ASV1)
292  a->inv_qscale = 6;
293  else
294  a->inv_qscale = 10;
295  }
296 
297  for (i = 0; i < 64; i++) {
298  int index = ff_asv_scantab[i];
299 
300  a->intra_matrix[i] = 64 * scale * ff_mpeg1_default_intra_matrix[index] / a->inv_qscale;
301  }
302 
303  p->qstride = a->mb_width;
304  p->qscale_table = av_malloc(p->qstride * a->mb_height);
305  p->quality = (32 * scale + a->inv_qscale / 2) / a->inv_qscale;
306  memset(p->qscale_table, p->quality, p->qstride * a->mb_height);
307 
308  return 0;
309 }
310 
312 {
313  ASV1Context * const a = avctx->priv_data;
314 
317  a->bitstream_buffer_size = 0;
318 
319  if (a->picture.data[0])
320  avctx->release_buffer(avctx, &a->picture);
321 
322  return 0;
323 }
324 
325 #if CONFIG_ASV1_DECODER
326 AVCodec ff_asv1_decoder = {
327  .name = "asv1",
328  .type = AVMEDIA_TYPE_VIDEO,
329  .id = AV_CODEC_ID_ASV1,
330  .priv_data_size = sizeof(ASV1Context),
331  .init = decode_init,
332  .close = decode_end,
333  .decode = decode_frame,
334  .capabilities = CODEC_CAP_DR1,
335  .long_name = NULL_IF_CONFIG_SMALL("ASUS V1"),
336 };
337 #endif
338 
339 #if CONFIG_ASV2_DECODER
340 AVCodec ff_asv2_decoder = {
341  .name = "asv2",
342  .type = AVMEDIA_TYPE_VIDEO,
343  .id = AV_CODEC_ID_ASV2,
344  .priv_data_size = sizeof(ASV1Context),
345  .init = decode_init,
346  .close = decode_end,
347  .decode = decode_frame,
348  .capabilities = CODEC_CAP_DR1,
349  .long_name = NULL_IF_CONFIG_SMALL("ASUS V2"),
350 };
351 #endif
352