Libav
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 
27 #define BITSTREAM_READER_LE
28 #include "libavutil/attributes.h"
29 #include "avcodec.h"
30 #include "get_bits.h"
31 #include "indeo2data.h"
32 #include "internal.h"
33 #include "mathops.h"
34 
35 typedef struct Ir2Context{
40 } Ir2Context;
41 
42 #define CODE_VLC_BITS 14
43 static VLC ir2_vlc;
44 
45 /* Indeo 2 codes are in range 0x01..0x7F and 0x81..0x90 */
46 static inline int ir2_get_code(GetBitContext *gb)
47 {
48  return get_vlc2(gb, ir2_vlc.table, CODE_VLC_BITS, 1) + 1;
49 }
50 
51 static int ir2_decode_plane(Ir2Context *ctx, int width, int height, uint8_t *dst,
52  int stride, const uint8_t *table)
53 {
54  int i;
55  int j;
56  int out = 0;
57  int c;
58  int t;
59 
60  if (width & 1)
61  return AVERROR_INVALIDDATA;
62 
63  /* first line contain absolute values, other lines contain deltas */
64  while (out < width) {
65  c = ir2_get_code(&ctx->gb);
66  if (c >= 0x80) { /* we have a run */
67  c -= 0x7F;
68  if (out + c*2 > width)
69  return AVERROR_INVALIDDATA;
70  for (i = 0; i < c * 2; i++)
71  dst[out++] = 0x80;
72  } else { /* copy two values from table */
73  dst[out++] = table[c * 2];
74  dst[out++] = table[(c * 2) + 1];
75  }
76  }
77  dst += stride;
78 
79  for (j = 1; j < height; j++) {
80  out = 0;
81  while (out < width) {
82  c = ir2_get_code(&ctx->gb);
83  if (c >= 0x80) { /* we have a skip */
84  c -= 0x7F;
85  if (out + c*2 > width)
86  return AVERROR_INVALIDDATA;
87  for (i = 0; i < c * 2; i++) {
88  dst[out] = dst[out - stride];
89  out++;
90  }
91  } else { /* add two deltas from table */
92  t = dst[out - stride] + (table[c * 2] - 128);
93  t = av_clip_uint8(t);
94  dst[out] = t;
95  out++;
96  t = dst[out - stride] + (table[(c * 2) + 1] - 128);
97  t = av_clip_uint8(t);
98  dst[out] = t;
99  out++;
100  }
101  }
102  dst += stride;
103  }
104  return 0;
105 }
106 
107 static int ir2_decode_plane_inter(Ir2Context *ctx, int width, int height, uint8_t *dst,
108  int stride, const uint8_t *table)
109 {
110  int j;
111  int out = 0;
112  int c;
113  int t;
114 
115  if (width & 1)
116  return AVERROR_INVALIDDATA;
117 
118  for (j = 0; j < height; j++) {
119  out = 0;
120  while (out < width) {
121  c = ir2_get_code(&ctx->gb);
122  if (c >= 0x80) { /* we have a skip */
123  c -= 0x7F;
124  out += c * 2;
125  } else { /* add two deltas from table */
126  t = dst[out] + (((table[c * 2] - 128)*3) >> 2);
127  t = av_clip_uint8(t);
128  dst[out] = t;
129  out++;
130  t = dst[out] + (((table[(c * 2) + 1] - 128)*3) >> 2);
131  t = av_clip_uint8(t);
132  dst[out] = t;
133  out++;
134  }
135  }
136  dst += stride;
137  }
138  return 0;
139 }
140 
142  void *data, int *got_frame,
143  AVPacket *avpkt)
144 {
145  Ir2Context * const s = avctx->priv_data;
146  const uint8_t *buf = avpkt->data;
147  int buf_size = avpkt->size;
148  AVFrame *picture = data;
149  AVFrame * const p = s->picture;
150  int start, ret;
151 
152  if ((ret = ff_reget_buffer(avctx, p)) < 0) {
153  av_log(s->avctx, AV_LOG_ERROR, "reget_buffer() failed\n");
154  return ret;
155  }
156 
157  start = 48; /* hardcoded for now */
158 
159  if (start >= buf_size) {
160  av_log(s->avctx, AV_LOG_ERROR, "input buffer size too small (%d)\n", buf_size);
161  return AVERROR_INVALIDDATA;
162  }
163 
164  s->decode_delta = buf[18];
165 
166  /* decide whether frame uses deltas or not */
167 #ifndef BITSTREAM_READER_LE
168  for (i = 0; i < buf_size; i++)
169  buf[i] = ff_reverse[buf[i]];
170 #endif
171 
172  init_get_bits(&s->gb, buf + start, (buf_size - start) * 8);
173 
174  if (s->decode_delta) { /* intraframe */
175  if ((ret = ir2_decode_plane(s, avctx->width, avctx->height,
176  p->data[0], p->linesize[0],
177  ir2_luma_table)) < 0)
178  return ret;
179 
180  /* swapped U and V */
181  if ((ret = ir2_decode_plane(s, avctx->width >> 2, avctx->height >> 2,
182  p->data[2], p->linesize[2],
183  ir2_luma_table)) < 0)
184  return ret;
185  if ((ret = ir2_decode_plane(s, avctx->width >> 2, avctx->height >> 2,
186  p->data[1], p->linesize[1],
187  ir2_luma_table)) < 0)
188  return ret;
189  } else { /* interframe */
190  if ((ret = ir2_decode_plane_inter(s, avctx->width, avctx->height,
191  p->data[0], p->linesize[0],
192  ir2_luma_table)) < 0)
193  return ret;
194  /* swapped U and V */
195  if ((ret = ir2_decode_plane_inter(s, avctx->width >> 2, avctx->height >> 2,
196  p->data[2], p->linesize[2],
197  ir2_luma_table)) < 0)
198  return ret;
199  if ((ret = ir2_decode_plane_inter(s, avctx->width >> 2, avctx->height >> 2,
200  p->data[1], p->linesize[1],
201  ir2_luma_table)) < 0)
202  return ret;
203  }
204 
205  if ((ret = av_frame_ref(picture, p)) < 0)
206  return ret;
207 
208  *got_frame = 1;
209 
210  return buf_size;
211 }
212 
214 {
215  Ir2Context * const ic = avctx->priv_data;
216  static VLC_TYPE vlc_tables[1 << CODE_VLC_BITS][2];
217 
218  ic->avctx = avctx;
219 
220  avctx->pix_fmt= AV_PIX_FMT_YUV410P;
221 
222  ic->picture = av_frame_alloc();
223  if (!ic->picture)
224  return AVERROR(ENOMEM);
225 
226  ir2_vlc.table = vlc_tables;
227  ir2_vlc.table_allocated = 1 << CODE_VLC_BITS;
228 #ifdef BITSTREAM_READER_LE
229  init_vlc(&ir2_vlc, CODE_VLC_BITS, IR2_CODES,
230  &ir2_codes[0][1], 4, 2,
232 #else
233  init_vlc(&ir2_vlc, CODE_VLC_BITS, IR2_CODES,
234  &ir2_codes[0][1], 4, 2,
235  &ir2_codes[0][0], 4, 2, INIT_VLC_USE_NEW_STATIC);
236 #endif
237 
238  return 0;
239 }
240 
242 {
243  Ir2Context * const ic = avctx->priv_data;
244 
245  av_frame_free(&ic->picture);
246 
247  return 0;
248 }
249 
251  .name = "indeo2",
252  .long_name = NULL_IF_CONFIG_SMALL("Intel Indeo 2"),
253  .type = AVMEDIA_TYPE_VIDEO,
254  .id = AV_CODEC_ID_INDEO2,
255  .priv_data_size = sizeof(Ir2Context),
259  .capabilities = CODEC_CAP_DR1,
260 };