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eatgq.c
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1 /*
2  * Electronic Arts TGQ Video Decoder
3  * Copyright (c) 2007-2008 Peter Ross <pross@xvid.org>
4  *
5  * This file is part of FFmpeg.
6  *
7  * FFmpeg is free software; you can redistribute it and/or
8  * modify it under the terms of the GNU Lesser General Public
9  * License as published by the Free Software Foundation; either
10  * version 2.1 of the License, or (at your option) any later version.
11  *
12  * FFmpeg is distributed in the hope that it will be useful,
13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15  * Lesser General Public License for more details.
16  *
17  * You should have received a copy of the GNU Lesser General Public
18  * License along with FFmpeg; if not, write to the Free Software
19  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
20  */
21 
22 /**
23  * @file
24  * Electronic Arts TGQ Video Decoder
25  * @author Peter Ross <pross@xvid.org>
26  *
27  * Technical details here:
28  * http://wiki.multimedia.cx/index.php?title=Electronic_Arts_TGQ
29  */
30 
31 #include "avcodec.h"
32 #define BITSTREAM_READER_LE
33 #include "get_bits.h"
34 #include "bytestream.h"
35 #include "dsputil.h"
36 #include "aandcttab.h"
37 #include "eaidct.h"
38 #include "internal.h"
39 
40 typedef struct TgqContext {
42  int width, height;
44  int qtable[64];
45  DECLARE_ALIGNED(16, int16_t, block)[6][64];
47 } TgqContext;
48 
50 {
51  TgqContext *s = avctx->priv_data;
52  uint8_t idct_permutation[64];
53  s->avctx = avctx;
55  ff_init_scantable(idct_permutation, &s->scantable, ff_zigzag_direct);
56  avctx->time_base = (AVRational){1, 15};
57  avctx->pix_fmt = AV_PIX_FMT_YUV420P;
58  return 0;
59 }
60 
61 static void tgq_decode_block(TgqContext *s, int16_t block[64], GetBitContext *gb)
62 {
64  int i, j, value;
65  block[0] = get_sbits(gb, 8) * s->qtable[0];
66  for (i = 1; i < 64;) {
67  switch (show_bits(gb, 3)) {
68  case 4:
69  block[perm[i++]] = 0;
70  case 0:
71  block[perm[i++]] = 0;
72  skip_bits(gb, 3);
73  break;
74  case 5:
75  case 1:
76  skip_bits(gb, 2);
77  value = get_bits(gb, 6);
78  for (j = 0; j < value; j++)
79  block[perm[i++]] = 0;
80  break;
81  case 6:
82  skip_bits(gb, 3);
83  block[perm[i]] = -s->qtable[perm[i]];
84  i++;
85  break;
86  case 2:
87  skip_bits(gb, 3);
88  block[perm[i]] = s->qtable[perm[i]];
89  i++;
90  break;
91  case 7: // 111b
92  case 3: // 011b
93  skip_bits(gb, 2);
94  if (show_bits(gb, 6) == 0x3F) {
95  skip_bits(gb, 6);
96  block[perm[i]] = get_sbits(gb, 8) * s->qtable[perm[i]];
97  } else {
98  block[perm[i]] = get_sbits(gb, 6) * s->qtable[perm[i]];
99  }
100  i++;
101  break;
102  }
103  }
104  block[0] += 128 << 4;
105 }
106 
107 static void tgq_idct_put_mb(TgqContext *s, int16_t (*block)[64], AVFrame *frame,
108  int mb_x, int mb_y)
109 {
110  int linesize = frame->linesize[0];
111  uint8_t *dest_y = frame->data[0] + (mb_y * 16 * linesize) + mb_x * 16;
112  uint8_t *dest_cb = frame->data[1] + (mb_y * 8 * frame->linesize[1]) + mb_x * 8;
113  uint8_t *dest_cr = frame->data[2] + (mb_y * 8 * frame->linesize[2]) + mb_x * 8;
114 
115  ff_ea_idct_put_c(dest_y , linesize, block[0]);
116  ff_ea_idct_put_c(dest_y + 8, linesize, block[1]);
117  ff_ea_idct_put_c(dest_y + 8 * linesize , linesize, block[2]);
118  ff_ea_idct_put_c(dest_y + 8 * linesize + 8, linesize, block[3]);
119  if (!(s->avctx->flags & CODEC_FLAG_GRAY)) {
120  ff_ea_idct_put_c(dest_cb, frame->linesize[1], block[4]);
121  ff_ea_idct_put_c(dest_cr, frame->linesize[2], block[5]);
122  }
123 }
124 
125 static inline void tgq_dconly(TgqContext *s, unsigned char *dst,
126  int dst_stride, int dc)
127 {
128  int level = av_clip_uint8((dc*s->qtable[0] + 2056) >> 4);
129  int j;
130  for (j = 0; j < 8; j++)
131  memset(dst + j * dst_stride, level, 8);
132 }
133 
135  int mb_x, int mb_y, const int8_t *dc)
136 {
137  int linesize = frame->linesize[0];
138  uint8_t *dest_y = frame->data[0] + (mb_y * 16 * linesize) + mb_x * 16;
139  uint8_t *dest_cb = frame->data[1] + (mb_y * 8 * frame->linesize[1]) + mb_x * 8;
140  uint8_t *dest_cr = frame->data[2] + (mb_y * 8 * frame->linesize[2]) + mb_x * 8;
141  tgq_dconly(s, dest_y, linesize, dc[0]);
142  tgq_dconly(s, dest_y + 8, linesize, dc[1]);
143  tgq_dconly(s, dest_y + 8 * linesize, linesize, dc[2]);
144  tgq_dconly(s, dest_y + 8 * linesize + 8, linesize, dc[3]);
145  if (!(s->avctx->flags & CODEC_FLAG_GRAY)) {
146  tgq_dconly(s, dest_cb, frame->linesize[1], dc[4]);
147  tgq_dconly(s, dest_cr, frame->linesize[2], dc[5]);
148  }
149 }
150 
151 static int tgq_decode_mb(TgqContext *s, AVFrame *frame, int mb_y, int mb_x)
152 {
153  int mode;
154  int i;
155  int8_t dc[6];
156 
157  mode = bytestream2_get_byte(&s->gb);
158  if (mode > 12) {
159  GetBitContext gb;
161  for (i = 0; i < 6; i++)
162  tgq_decode_block(s, s->block[i], &gb);
163  tgq_idct_put_mb(s, s->block, frame, mb_x, mb_y);
164  bytestream2_skip(&s->gb, mode);
165  } else {
166  if (mode == 3) {
167  memset(dc, bytestream2_get_byte(&s->gb), 4);
168  dc[4] = bytestream2_get_byte(&s->gb);
169  dc[5] = bytestream2_get_byte(&s->gb);
170  } else if (mode == 6) {
171  bytestream2_get_buffer(&s->gb, dc, 6);
172  } else if (mode == 12) {
173  for (i = 0; i < 6; i++) {
174  dc[i] = bytestream2_get_byte(&s->gb);
175  bytestream2_skip(&s->gb, 1);
176  }
177  } else {
178  av_log(s->avctx, AV_LOG_ERROR, "unsupported mb mode %i\n", mode);
179  return -1;
180  }
181  tgq_idct_put_mb_dconly(s, frame, mb_x, mb_y, dc);
182  }
183  return 0;
184 }
185 
187 {
188  int i, j;
189  const int a = (14 * (100 - quant)) / 100 + 1;
190  const int b = (11 * (100 - quant)) / 100 + 4;
191  for (j = 0; j < 8; j++)
192  for (i = 0; i < 8; i++)
193  s->qtable[j * 8 + i] = ((a * (j + i) / (7 + 7) + b) *
194  ff_inv_aanscales[j * 8 + i]) >> (14 - 4);
195 }
196 
198  void *data, int *got_frame,
199  AVPacket *avpkt)
200 {
201  const uint8_t *buf = avpkt->data;
202  int buf_size = avpkt->size;
203  TgqContext *s = avctx->priv_data;
204  AVFrame *frame = data;
205  int x, y, ret;
206  int big_endian;
207 
208  if (buf_size < 16) {
209  av_log(avctx, AV_LOG_WARNING, "truncated header\n");
210  return AVERROR_INVALIDDATA;
211  }
212  big_endian = AV_RL32(&buf[4]) > 0x000FFFFF;
213  bytestream2_init(&s->gb, buf + 8, buf_size - 8);
214  if (big_endian) {
215  s->width = bytestream2_get_be16u(&s->gb);
216  s->height = bytestream2_get_be16u(&s->gb);
217  } else {
218  s->width = bytestream2_get_le16u(&s->gb);
219  s->height = bytestream2_get_le16u(&s->gb);
220  }
221 
222  ret = ff_set_dimensions(s->avctx, s->width, s->height);
223  if (ret < 0)
224  return ret;
225 
226  tgq_calculate_qtable(s, bytestream2_get_byteu(&s->gb));
227  bytestream2_skip(&s->gb, 3);
228 
229  if ((ret = ff_get_buffer(avctx, frame, 0)) < 0)
230  return ret;
231  frame->key_frame = 1;
232  frame->pict_type = AV_PICTURE_TYPE_I;
233 
234  for (y = 0; y < FFALIGN(avctx->height, 16) >> 4; y++)
235  for (x = 0; x < FFALIGN(avctx->width, 16) >> 4; x++)
236  if (tgq_decode_mb(s, frame, y, x) < 0)
237  return AVERROR_INVALIDDATA;
238 
239  *got_frame = 1;
240 
241  return avpkt->size;
242 }
243 
245  .name = "eatgq",
246  .long_name = NULL_IF_CONFIG_SMALL("Electronic Arts TGQ video"),
247  .type = AVMEDIA_TYPE_VIDEO,
248  .id = AV_CODEC_ID_TGQ,
249  .priv_data_size = sizeof(TgqContext),
252  .capabilities = CODEC_CAP_DR1,
253 };