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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 "internal.h"
32 #include "mathops.h"
33 #include "mpeg12data.h"
34 
35 #define VLC_BITS 6
36 #define ASV2_LEVEL_VLC_BITS 10
37 
38 static VLC ccp_vlc;
39 static VLC level_vlc;
40 static VLC dc_ccp_vlc;
41 static VLC ac_ccp_vlc;
43 
45 {
46  static int done = 0;
47 
48  if (!done) {
49  done = 1;
50 
51  INIT_VLC_STATIC(&ccp_vlc, VLC_BITS, 17,
52  &ff_asv_ccp_tab[0][1], 2, 1,
53  &ff_asv_ccp_tab[0][0], 2, 1, 64);
54  INIT_VLC_STATIC(&dc_ccp_vlc, VLC_BITS, 8,
55  &ff_asv_dc_ccp_tab[0][1], 2, 1,
56  &ff_asv_dc_ccp_tab[0][0], 2, 1, 64);
57  INIT_VLC_STATIC(&ac_ccp_vlc, VLC_BITS, 16,
58  &ff_asv_ac_ccp_tab[0][1], 2, 1,
59  &ff_asv_ac_ccp_tab[0][0], 2, 1, 64);
60  INIT_VLC_STATIC(&level_vlc, VLC_BITS, 7,
61  &ff_asv_level_tab[0][1], 2, 1,
62  &ff_asv_level_tab[0][0], 2, 1, 64);
63  INIT_VLC_STATIC(&asv2_level_vlc, ASV2_LEVEL_VLC_BITS, 63,
64  &ff_asv2_level_tab[0][1], 2, 1,
65  &ff_asv2_level_tab[0][0], 2, 1, 1024);
66  }
67 }
68 
69 //FIXME write a reversed bitstream reader to avoid the double reverse
70 static inline int asv2_get_bits(GetBitContext *gb, int n)
71 {
72  return ff_reverse[get_bits(gb, n) << (8-n)];
73 }
74 
75 static inline int asv1_get_level(GetBitContext *gb)
76 {
77  int code = get_vlc2(gb, level_vlc.table, VLC_BITS, 1);
78 
79  if (code == 3)
80  return get_sbits(gb, 8);
81  else
82  return code - 3;
83 }
84 
85 static inline int asv2_get_level(GetBitContext *gb)
86 {
87  int code = get_vlc2(gb, asv2_level_vlc.table, ASV2_LEVEL_VLC_BITS, 1);
88 
89  if (code == 31)
90  return (int8_t)asv2_get_bits(gb, 8);
91  else
92  return code - 31;
93 }
94 
95 static inline int asv1_decode_block(ASV1Context *a, int16_t block[64])
96 {
97  int i;
98 
99  block[0] = 8 * get_bits(&a->gb, 8);
100 
101  for (i = 0; i < 11; i++) {
102  const int ccp = get_vlc2(&a->gb, ccp_vlc.table, VLC_BITS, 1);
103 
104  if (ccp) {
105  if (ccp == 16)
106  break;
107  if (ccp < 0 || i >= 10) {
108  av_log(a->avctx, AV_LOG_ERROR, "coded coeff pattern damaged\n");
109  return AVERROR_INVALIDDATA;
110  }
111 
112  if (ccp & 8)
113  block[a->scantable.permutated[4 * i + 0]] = (asv1_get_level(&a->gb) * a->intra_matrix[4 * i + 0]) >> 4;
114  if (ccp & 4)
115  block[a->scantable.permutated[4 * i + 1]] = (asv1_get_level(&a->gb) * a->intra_matrix[4 * i + 1]) >> 4;
116  if (ccp & 2)
117  block[a->scantable.permutated[4 * i + 2]] = (asv1_get_level(&a->gb) * a->intra_matrix[4 * i + 2]) >> 4;
118  if (ccp & 1)
119  block[a->scantable.permutated[4 * i + 3]] = (asv1_get_level(&a->gb) * a->intra_matrix[4 * i + 3]) >> 4;
120  }
121  }
122 
123  return 0;
124 }
125 
126 static inline int asv2_decode_block(ASV1Context *a, int16_t block[64])
127 {
128  int i, count, ccp;
129 
130  count = asv2_get_bits(&a->gb, 4);
131 
132  block[0] = 8 * asv2_get_bits(&a->gb, 8);
133 
134  ccp = get_vlc2(&a->gb, dc_ccp_vlc.table, VLC_BITS, 1);
135  if (ccp) {
136  if (ccp & 4)
137  block[a->scantable.permutated[1]] = (asv2_get_level(&a->gb) * a->intra_matrix[1]) >> 4;
138  if (ccp & 2)
139  block[a->scantable.permutated[2]] = (asv2_get_level(&a->gb) * a->intra_matrix[2]) >> 4;
140  if (ccp & 1)
141  block[a->scantable.permutated[3]] = (asv2_get_level(&a->gb) * a->intra_matrix[3]) >> 4;
142  }
143 
144  for (i = 1; i < count + 1; i++) {
145  const int ccp = get_vlc2(&a->gb, ac_ccp_vlc.table, VLC_BITS, 1);
146 
147  if (ccp) {
148  if (ccp & 8)
149  block[a->scantable.permutated[4*i + 0]] = (asv2_get_level(&a->gb) * a->intra_matrix[4*i + 0]) >> 4;
150  if (ccp & 4)
151  block[a->scantable.permutated[4*i + 1]] = (asv2_get_level(&a->gb) * a->intra_matrix[4*i + 1]) >> 4;
152  if (ccp & 2)
153  block[a->scantable.permutated[4*i + 2]] = (asv2_get_level(&a->gb) * a->intra_matrix[4*i + 2]) >> 4;
154  if (ccp & 1)
155  block[a->scantable.permutated[4*i + 3]] = (asv2_get_level(&a->gb) * a->intra_matrix[4*i + 3]) >> 4;
156  }
157  }
158 
159  return 0;
160 }
161 
162 static inline int decode_mb(ASV1Context *a, int16_t block[6][64])
163 {
164  int i;
165 
166  a->dsp.clear_blocks(block[0]);
167 
168  if (a->avctx->codec_id == AV_CODEC_ID_ASV1) {
169  for (i = 0; i < 6; i++) {
170  if (asv1_decode_block(a, block[i]) < 0)
171  return -1;
172  }
173  } else {
174  for (i = 0; i < 6; i++) {
175  if (asv2_decode_block(a, block[i]) < 0)
176  return -1;
177  }
178  }
179  return 0;
180 }
181 
182 static inline void idct_put(ASV1Context *a, AVFrame *frame, int mb_x, int mb_y)
183 {
184  int16_t (*block)[64] = a->block;
185  int linesize = frame->linesize[0];
186 
187  uint8_t *dest_y = frame->data[0] + (mb_y * 16* linesize ) + mb_x * 16;
188  uint8_t *dest_cb = frame->data[1] + (mb_y * 8 * frame->linesize[1]) + mb_x * 8;
189  uint8_t *dest_cr = frame->data[2] + (mb_y * 8 * frame->linesize[2]) + mb_x * 8;
190 
191  a->dsp.idct_put(dest_y , linesize, block[0]);
192  a->dsp.idct_put(dest_y + 8, linesize, block[1]);
193  a->dsp.idct_put(dest_y + 8*linesize , linesize, block[2]);
194  a->dsp.idct_put(dest_y + 8*linesize + 8, linesize, block[3]);
195 
196  if (!(a->avctx->flags&CODEC_FLAG_GRAY)) {
197  a->dsp.idct_put(dest_cb, frame->linesize[1], block[4]);
198  a->dsp.idct_put(dest_cr, frame->linesize[2], block[5]);
199  }
200 }
201 
202 static int decode_frame(AVCodecContext *avctx,
203  void *data, int *got_frame,
204  AVPacket *avpkt)
205 {
206  ASV1Context * const a = avctx->priv_data;
207  const uint8_t *buf = avpkt->data;
208  int buf_size = avpkt->size;
209  AVFrame * const p = data;
210  int mb_x, mb_y, ret;
211 
212  if ((ret = ff_get_buffer(avctx, p, 0)) < 0)
213  return ret;
215  p->key_frame = 1;
216 
218  buf_size);
219  if (!a->bitstream_buffer)
220  return AVERROR(ENOMEM);
221 
222  if (avctx->codec_id == AV_CODEC_ID_ASV1)
223  a->dsp.bswap_buf((uint32_t*)a->bitstream_buffer, (const uint32_t*)buf, buf_size/4);
224  else {
225  int i;
226  for (i = 0; i < buf_size; i++)
227  a->bitstream_buffer[i] = ff_reverse[buf[i]];
228  }
229 
230  init_get_bits(&a->gb, a->bitstream_buffer, buf_size*8);
231 
232  for (mb_y = 0; mb_y < a->mb_height2; mb_y++) {
233  for (mb_x = 0; mb_x < a->mb_width2; mb_x++) {
234  if ((ret = decode_mb(a, a->block)) < 0)
235  return ret;
236 
237  idct_put(a, p, mb_x, mb_y);
238  }
239  }
240 
241  if (a->mb_width2 != a->mb_width) {
242  mb_x = a->mb_width2;
243  for (mb_y = 0; mb_y < a->mb_height2; mb_y++) {
244  if ((ret = decode_mb(a, a->block)) < 0)
245  return ret;
246 
247  idct_put(a, p, mb_x, mb_y);
248  }
249  }
250 
251  if (a->mb_height2 != a->mb_height) {
252  mb_y = a->mb_height2;
253  for (mb_x = 0; mb_x < a->mb_width; mb_x++) {
254  if ((ret = decode_mb(a, a->block)) < 0)
255  return ret;
256 
257  idct_put(a, p, mb_x, mb_y);
258  }
259  }
260 
261  *got_frame = 1;
262 
263  emms_c();
264 
265  return (get_bits_count(&a->gb) + 31) / 32 * 4;
266 }
267 
269 {
270  ASV1Context * const a = avctx->priv_data;
271  const int scale = avctx->codec_id == AV_CODEC_ID_ASV1 ? 1 : 2;
272  int i;
273 
274  ff_asv_common_init(avctx);
275  init_vlcs(a);
277  avctx->pix_fmt = AV_PIX_FMT_YUV420P;
278 
279  if (avctx->extradata_size < 1 || (a->inv_qscale = avctx->extradata[0]) == 0) {
280  av_log(avctx, AV_LOG_ERROR, "illegal qscale 0\n");
281  if (avctx->codec_id == AV_CODEC_ID_ASV1)
282  a->inv_qscale = 6;
283  else
284  a->inv_qscale = 10;
285  }
286 
287  for (i = 0; i < 64; i++) {
288  int index = ff_asv_scantab[i];
289 
290  a->intra_matrix[i] = 64 * scale * ff_mpeg1_default_intra_matrix[index] / a->inv_qscale;
291  }
292 
293  return 0;
294 }
295 
297 {
298  ASV1Context * const a = avctx->priv_data;
299 
301  a->bitstream_buffer_size = 0;
302 
303  return 0;
304 }
305 
306 #if CONFIG_ASV1_DECODER
307 AVCodec ff_asv1_decoder = {
308  .name = "asv1",
309  .type = AVMEDIA_TYPE_VIDEO,
310  .id = AV_CODEC_ID_ASV1,
311  .priv_data_size = sizeof(ASV1Context),
312  .init = decode_init,
313  .close = decode_end,
314  .decode = decode_frame,
315  .capabilities = CODEC_CAP_DR1,
316  .long_name = NULL_IF_CONFIG_SMALL("ASUS V1"),
317 };
318 #endif
319 
320 #if CONFIG_ASV2_DECODER
321 AVCodec ff_asv2_decoder = {
322  .name = "asv2",
323  .type = AVMEDIA_TYPE_VIDEO,
324  .id = AV_CODEC_ID_ASV2,
325  .priv_data_size = sizeof(ASV1Context),
326  .init = decode_init,
327  .close = decode_end,
328  .decode = decode_frame,
329  .capabilities = CODEC_CAP_DR1,
330  .long_name = NULL_IF_CONFIG_SMALL("ASUS V2"),
331 };
332 #endif
333