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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 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 Street, Fifth Floor, Boston, MA 02110-1301 USA
20  */
21 
22 /**
23  * @file
24  * Intel Indeo 2 decoder.
25  */
26 
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 pitch, const uint8_t *table)
53 {
54  int i;
55  int j;
56  int out = 0;
57 
58  if (width & 1)
59  return AVERROR_INVALIDDATA;
60 
61  /* first line contain absolute values, other lines contain deltas */
62  while (out < width) {
63  int c = ir2_get_code(&ctx->gb);
64  if (c >= 0x80) { /* we have a run */
65  c -= 0x7F;
66  if (out + c*2 > width)
67  return AVERROR_INVALIDDATA;
68  for (i = 0; i < c * 2; i++)
69  dst[out++] = 0x80;
70  } else { /* copy two values from table */
71  dst[out++] = table[c * 2];
72  dst[out++] = table[(c * 2) + 1];
73  }
74  }
75  dst += pitch;
76 
77  for (j = 1; j < height; j++) {
78  out = 0;
79  while (out < width) {
80  int c = ir2_get_code(&ctx->gb);
81  if (c >= 0x80) { /* we have a skip */
82  c -= 0x7F;
83  if (out + c*2 > width)
84  return AVERROR_INVALIDDATA;
85  for (i = 0; i < c * 2; i++) {
86  dst[out] = dst[out - pitch];
87  out++;
88  }
89  } else { /* add two deltas from table */
90  int t = dst[out - pitch] + (table[c * 2] - 128);
91  t = av_clip_uint8(t);
92  dst[out] = t;
93  out++;
94  t = dst[out - pitch] + (table[(c * 2) + 1] - 128);
95  t = av_clip_uint8(t);
96  dst[out] = t;
97  out++;
98  }
99  }
100  dst += pitch;
101  }
102  return 0;
103 }
104 
105 static int ir2_decode_plane_inter(Ir2Context *ctx, int width, int height, uint8_t *dst,
106  int pitch, const uint8_t *table)
107 {
108  int j;
109  int out = 0;
110  int c;
111  int t;
112 
113  if (width & 1)
114  return AVERROR_INVALIDDATA;
115 
116  for (j = 0; j < height; j++) {
117  out = 0;
118  while (out < width) {
119  c = ir2_get_code(&ctx->gb);
120  if (c >= 0x80) { /* we have a skip */
121  c -= 0x7F;
122  out += c * 2;
123  } else { /* add two deltas from table */
124  t = dst[out] + (((table[c * 2] - 128)*3) >> 2);
125  t = av_clip_uint8(t);
126  dst[out] = t;
127  out++;
128  t = dst[out] + (((table[(c * 2) + 1] - 128)*3) >> 2);
129  t = av_clip_uint8(t);
130  dst[out] = t;
131  out++;
132  }
133  }
134  dst += pitch;
135  }
136  return 0;
137 }
138 
140  void *data, int *got_frame,
141  AVPacket *avpkt)
142 {
143  Ir2Context * const s = avctx->priv_data;
144  const uint8_t *buf = avpkt->data;
145  int buf_size = avpkt->size;
146  AVFrame *picture = data;
147  AVFrame * const p = s->picture;
148  int start, ret;
149 
150  if ((ret = ff_reget_buffer(avctx, p)) < 0)
151  return ret;
152 
153  start = 48; /* hardcoded for now */
154 
155  if (start >= buf_size) {
156  av_log(s->avctx, AV_LOG_ERROR, "input buffer size too small (%d)\n", buf_size);
157  return AVERROR_INVALIDDATA;
158  }
159 
160  s->decode_delta = buf[18];
161 
162  /* decide whether frame uses deltas or not */
163 #ifndef BITSTREAM_READER_LE
164  for (i = 0; i < buf_size; i++)
165  buf[i] = ff_reverse[buf[i]];
166 #endif
167 
168  init_get_bits(&s->gb, buf + start, (buf_size - start) * 8);
169 
170  if (s->decode_delta) { /* intraframe */
171  if ((ret = ir2_decode_plane(s, avctx->width, avctx->height,
172  p->data[0], p->linesize[0],
173  ir2_luma_table)) < 0)
174  return ret;
175 
176  /* swapped U and V */
177  if ((ret = ir2_decode_plane(s, avctx->width >> 2, avctx->height >> 2,
178  p->data[2], p->linesize[2],
179  ir2_luma_table)) < 0)
180  return ret;
181  if ((ret = ir2_decode_plane(s, avctx->width >> 2, avctx->height >> 2,
182  p->data[1], p->linesize[1],
183  ir2_luma_table)) < 0)
184  return ret;
185  } else { /* interframe */
186  if ((ret = ir2_decode_plane_inter(s, avctx->width, avctx->height,
187  p->data[0], p->linesize[0],
188  ir2_luma_table)) < 0)
189  return ret;
190  /* swapped U and V */
191  if ((ret = ir2_decode_plane_inter(s, avctx->width >> 2, avctx->height >> 2,
192  p->data[2], p->linesize[2],
193  ir2_luma_table)) < 0)
194  return ret;
195  if ((ret = ir2_decode_plane_inter(s, avctx->width >> 2, avctx->height >> 2,
196  p->data[1], p->linesize[1],
197  ir2_luma_table)) < 0)
198  return ret;
199  }
200 
201  if ((ret = av_frame_ref(picture, p)) < 0)
202  return ret;
203 
204  *got_frame = 1;
205 
206  return buf_size;
207 }
208 
210 {
211  Ir2Context * const ic = avctx->priv_data;
212  static VLC_TYPE vlc_tables[1 << CODE_VLC_BITS][2];
213 
214  ic->avctx = avctx;
215 
216  avctx->pix_fmt= AV_PIX_FMT_YUV410P;
217 
218  ic->picture = av_frame_alloc();
219  if (!ic->picture)
220  return AVERROR(ENOMEM);
221 
222  ir2_vlc.table = vlc_tables;
223  ir2_vlc.table_allocated = 1 << CODE_VLC_BITS;
224 #ifdef BITSTREAM_READER_LE
225  init_vlc(&ir2_vlc, CODE_VLC_BITS, IR2_CODES,
226  &ir2_codes[0][1], 4, 2,
228 #else
229  init_vlc(&ir2_vlc, CODE_VLC_BITS, IR2_CODES,
230  &ir2_codes[0][1], 4, 2,
231  &ir2_codes[0][0], 4, 2, INIT_VLC_USE_NEW_STATIC);
232 #endif
233 
234  return 0;
235 }
236 
238 {
239  Ir2Context * const ic = avctx->priv_data;
240 
241  av_frame_free(&ic->picture);
242 
243  return 0;
244 }
245 
247  .name = "indeo2",
248  .long_name = NULL_IF_CONFIG_SMALL("Intel Indeo 2"),
249  .type = AVMEDIA_TYPE_VIDEO,
250  .id = AV_CODEC_ID_INDEO2,
251  .priv_data_size = sizeof(Ir2Context),
253  .close = ir2_decode_end,
255  .capabilities = CODEC_CAP_DR1,
256 };