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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 "blockdsp.h"
32 #include "idctdsp.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, int16_t 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 AVERROR_INVALIDDATA;
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, int16_t 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, int16_t block[6][64])
165 {
166  int i;
167 
168  a->bdsp.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, AVFrame *frame, int mb_x, int mb_y)
185 {
186  int16_t(*block)[64] = a->block;
187  int linesize = frame->linesize[0];
188 
189  uint8_t *dest_y = frame->data[0] + (mb_y * 16 * linesize) + mb_x * 16;
190  uint8_t *dest_cb = frame->data[1] + (mb_y * 8 * frame->linesize[1]) + mb_x * 8;
191  uint8_t *dest_cr = frame->data[2] + (mb_y * 8 * frame->linesize[2]) + mb_x * 8;
192 
193  a->idsp.idct_put(dest_y, linesize, block[0]);
194  a->idsp.idct_put(dest_y + 8, linesize, block[1]);
195  a->idsp.idct_put(dest_y + 8 * linesize, linesize, block[2]);
196  a->idsp.idct_put(dest_y + 8 * linesize + 8, linesize, block[3]);
197 
198  if (!(a->avctx->flags & CODEC_FLAG_GRAY)) {
199  a->idsp.idct_put(dest_cb, frame->linesize[1], block[4]);
200  a->idsp.idct_put(dest_cr, frame->linesize[2], block[5]);
201  }
202 }
203 
204 static int decode_frame(AVCodecContext *avctx, 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  return ret;
216  p->key_frame = 1;
217 
219  buf_size);
220  if (!a->bitstream_buffer)
221  return AVERROR(ENOMEM);
222 
223  if (avctx->codec_id == AV_CODEC_ID_ASV1) {
224  a->bbdsp.bswap_buf((uint32_t *) a->bitstream_buffer,
225  (const uint32_t *) buf, buf_size / 4);
226  } else {
227  int i;
228  for (i = 0; i < buf_size; i++)
229  a->bitstream_buffer[i] = ff_reverse[buf[i]];
230  }
231 
232  init_get_bits(&a->gb, a->bitstream_buffer, buf_size * 8);
233 
234  for (mb_y = 0; mb_y < a->mb_height2; mb_y++) {
235  for (mb_x = 0; mb_x < a->mb_width2; mb_x++) {
236  if ((ret = decode_mb(a, a->block)) < 0)
237  return ret;
238 
239  idct_put(a, p, mb_x, mb_y);
240  }
241  }
242 
243  if (a->mb_width2 != a->mb_width) {
244  mb_x = a->mb_width2;
245  for (mb_y = 0; mb_y < a->mb_height2; mb_y++) {
246  if ((ret = decode_mb(a, a->block)) < 0)
247  return ret;
248 
249  idct_put(a, p, mb_x, mb_y);
250  }
251  }
252 
253  if (a->mb_height2 != a->mb_height) {
254  mb_y = a->mb_height2;
255  for (mb_x = 0; mb_x < a->mb_width; mb_x++) {
256  if ((ret = decode_mb(a, a->block)) < 0)
257  return ret;
258 
259  idct_put(a, p, mb_x, mb_y);
260  }
261  }
262 
263  *got_frame = 1;
264 
265  emms_c();
266 
267  return (get_bits_count(&a->gb) + 31) / 32 * 4;
268 }
269 
271 {
272  ASV1Context *const a = avctx->priv_data;
273  const int scale = avctx->codec_id == AV_CODEC_ID_ASV1 ? 1 : 2;
274  int i;
275 
276  if (avctx->extradata_size < 1) {
277  av_log(avctx, AV_LOG_WARNING, "No extradata provided\n");
278  }
279 
280  ff_asv_common_init(avctx);
281  ff_blockdsp_init(&a->bdsp, avctx);
282  ff_idctdsp_init(&a->idsp, avctx);
283  init_vlcs(a);
285  avctx->pix_fmt = AV_PIX_FMT_YUV420P;
286 
287  if (avctx->extradata_size < 1 || (a->inv_qscale = avctx->extradata[0]) == 0) {
288  av_log(avctx, AV_LOG_ERROR, "illegal qscale 0\n");
289  if (avctx->codec_id == AV_CODEC_ID_ASV1)
290  a->inv_qscale = 6;
291  else
292  a->inv_qscale = 10;
293  }
294 
295  for (i = 0; i < 64; i++) {
296  int index = ff_asv_scantab[i];
297 
298  a->intra_matrix[i] = 64 * scale * ff_mpeg1_default_intra_matrix[index] /
299  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 
315 #if CONFIG_ASV1_DECODER
316 AVCodec ff_asv1_decoder = {
317  .name = "asv1",
318  .long_name = NULL_IF_CONFIG_SMALL("ASUS V1"),
319  .type = AVMEDIA_TYPE_VIDEO,
320  .id = AV_CODEC_ID_ASV1,
321  .priv_data_size = sizeof(ASV1Context),
322  .init = decode_init,
323  .close = decode_end,
324  .decode = decode_frame,
325  .capabilities = CODEC_CAP_DR1,
326 };
327 #endif
328 
329 #if CONFIG_ASV2_DECODER
330 AVCodec ff_asv2_decoder = {
331  .name = "asv2",
332  .long_name = NULL_IF_CONFIG_SMALL("ASUS V2"),
333  .type = AVMEDIA_TYPE_VIDEO,
334  .id = AV_CODEC_ID_ASV2,
335  .priv_data_size = sizeof(ASV1Context),
336  .init = decode_init,
337  .close = decode_end,
338  .decode = decode_frame,
339  .capabilities = CODEC_CAP_DR1,
340 };
341 #endif