indeo2.c
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1 /*
2  * Intel Indeo 2 codec
3  * Copyright (c) 2005 Konstantin Shishkov
4  *
5  * This file is part of Libav.
6  *
7  * Libav 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  * Libav 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 Libav; if not, write to the Free Software
19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20  */
21 
26 #define BITSTREAM_READER_LE
27 #include "avcodec.h"
28 #include "get_bits.h"
29 #include "indeo2data.h"
30 #include "libavutil/common.h"
31 
32 typedef struct Ir2Context{
37 } Ir2Context;
38 
39 #define CODE_VLC_BITS 14
40 static VLC ir2_vlc;
41 
42 /* Indeo 2 codes are in range 0x01..0x7F and 0x81..0x90 */
43 static inline int ir2_get_code(GetBitContext *gb)
44 {
45  return get_vlc2(gb, ir2_vlc.table, CODE_VLC_BITS, 1) + 1;
46 }
47 
48 static int ir2_decode_plane(Ir2Context *ctx, int width, int height, uint8_t *dst, int stride,
49  const uint8_t *table)
50 {
51  int i;
52  int j;
53  int out = 0;
54  int c;
55  int t;
56 
57  if(width&1)
58  return -1;
59 
60  /* first line contain absolute values, other lines contain deltas */
61  while (out < width){
62  c = ir2_get_code(&ctx->gb);
63  if(c >= 0x80) { /* we have a run */
64  c -= 0x7F;
65  if(out + c*2 > width)
66  return -1;
67  for (i = 0; i < c * 2; i++)
68  dst[out++] = 0x80;
69  } else { /* copy two values from table */
70  dst[out++] = table[c * 2];
71  dst[out++] = table[(c * 2) + 1];
72  }
73  }
74  dst += stride;
75 
76  for (j = 1; j < height; j++){
77  out = 0;
78  while (out < width){
79  c = ir2_get_code(&ctx->gb);
80  if(c >= 0x80) { /* we have a skip */
81  c -= 0x7F;
82  if(out + c*2 > width)
83  return -1;
84  for (i = 0; i < c * 2; i++) {
85  dst[out] = dst[out - stride];
86  out++;
87  }
88  } else { /* add two deltas from table */
89  t = dst[out - stride] + (table[c * 2] - 128);
90  t= av_clip_uint8(t);
91  dst[out] = t;
92  out++;
93  t = dst[out - stride] + (table[(c * 2) + 1] - 128);
94  t= av_clip_uint8(t);
95  dst[out] = t;
96  out++;
97  }
98  }
99  dst += stride;
100  }
101  return 0;
102 }
103 
104 static int ir2_decode_plane_inter(Ir2Context *ctx, int width, int height, uint8_t *dst, int stride,
105  const uint8_t *table)
106 {
107  int j;
108  int out = 0;
109  int c;
110  int t;
111 
112  if(width&1)
113  return -1;
114 
115  for (j = 0; j < height; j++){
116  out = 0;
117  while (out < width){
118  c = ir2_get_code(&ctx->gb);
119  if(c >= 0x80) { /* we have a skip */
120  c -= 0x7F;
121  out += c * 2;
122  } else { /* add two deltas from table */
123  t = dst[out] + (((table[c * 2] - 128)*3) >> 2);
124  t= av_clip_uint8(t);
125  dst[out] = t;
126  out++;
127  t = dst[out] + (((table[(c * 2) + 1] - 128)*3) >> 2);
128  t= av_clip_uint8(t);
129  dst[out] = t;
130  out++;
131  }
132  }
133  dst += stride;
134  }
135  return 0;
136 }
137 
139  void *data, int *data_size,
140  AVPacket *avpkt)
141 {
142  const uint8_t *buf = avpkt->data;
143  int buf_size = avpkt->size;
144  Ir2Context * const s = avctx->priv_data;
145  AVFrame *picture = data;
146  AVFrame * const p= (AVFrame*)&s->picture;
147  int start;
148 
149  if(p->data[0])
150  avctx->release_buffer(avctx, p);
151 
152  p->reference = 1;
154  if (avctx->reget_buffer(avctx, p)) {
155  av_log(s->avctx, AV_LOG_ERROR, "reget_buffer() failed\n");
156  return -1;
157  }
158 
159  start = 48; /* hardcoded for now */
160 
161  if (start >= buf_size) {
162  av_log(s->avctx, AV_LOG_ERROR, "input buffer size too small (%d)\n", buf_size);
163  return AVERROR_INVALIDDATA;
164  }
165 
166  s->decode_delta = buf[18];
167 
168  /* decide whether frame uses deltas or not */
169 #ifndef BITSTREAM_READER_LE
170  for (i = 0; i < buf_size; i++)
171  buf[i] = av_reverse[buf[i]];
172 #endif
173 
174  init_get_bits(&s->gb, buf + start, (buf_size - start) * 8);
175 
176  if (s->decode_delta) { /* intraframe */
177  ir2_decode_plane(s, avctx->width, avctx->height,
178  s->picture.data[0], s->picture.linesize[0], ir2_luma_table);
179  /* swapped U and V */
180  ir2_decode_plane(s, avctx->width >> 2, avctx->height >> 2,
181  s->picture.data[2], s->picture.linesize[2], ir2_luma_table);
182  ir2_decode_plane(s, avctx->width >> 2, avctx->height >> 2,
183  s->picture.data[1], s->picture.linesize[1], ir2_luma_table);
184  } else { /* interframe */
185  ir2_decode_plane_inter(s, avctx->width, avctx->height,
186  s->picture.data[0], s->picture.linesize[0], ir2_luma_table);
187  /* swapped U and V */
188  ir2_decode_plane_inter(s, avctx->width >> 2, avctx->height >> 2,
189  s->picture.data[2], s->picture.linesize[2], ir2_luma_table);
190  ir2_decode_plane_inter(s, avctx->width >> 2, avctx->height >> 2,
191  s->picture.data[1], s->picture.linesize[1], ir2_luma_table);
192  }
193 
194  *picture= *(AVFrame*)&s->picture;
195  *data_size = sizeof(AVPicture);
196 
197  return buf_size;
198 }
199 
201  Ir2Context * const ic = avctx->priv_data;
202  static VLC_TYPE vlc_tables[1 << CODE_VLC_BITS][2];
203 
204  ic->avctx = avctx;
205 
206  avctx->pix_fmt= PIX_FMT_YUV410P;
207 
208  ir2_vlc.table = vlc_tables;
209  ir2_vlc.table_allocated = 1 << CODE_VLC_BITS;
210 #ifdef BITSTREAM_READER_LE
211  init_vlc(&ir2_vlc, CODE_VLC_BITS, IR2_CODES,
212  &ir2_codes[0][1], 4, 2,
214 #else
215  init_vlc(&ir2_vlc, CODE_VLC_BITS, IR2_CODES,
216  &ir2_codes[0][1], 4, 2,
217  &ir2_codes[0][0], 4, 2, INIT_VLC_USE_NEW_STATIC);
218 #endif
219 
220  return 0;
221 }
222 
224  Ir2Context * const ic = avctx->priv_data;
225  AVFrame *pic = &ic->picture;
226 
227  if (pic->data[0])
228  avctx->release_buffer(avctx, pic);
229 
230  return 0;
231 }
232 
234  .name = "indeo2",
235  .type = AVMEDIA_TYPE_VIDEO,
236  .id = CODEC_ID_INDEO2,
237  .priv_data_size = sizeof(Ir2Context),
241  .capabilities = CODEC_CAP_DR1,
242  .long_name = NULL_IF_CONFIG_SMALL("Intel Indeo 2"),
243 };