anm.c
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1 /*
2  * Deluxe Paint Animation demuxer
3  * Copyright (c) 2009 Peter Ross
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 #include "libavutil/intreadwrite.h"
28 #include "avformat.h"
29 #include "internal.h"
30 
31 typedef struct {
33  unsigned int nb_records;
34  int size;
35 } Page;
36 
37 typedef struct {
38  unsigned int nb_pages;
39  unsigned int nb_records;
41 #define MAX_PAGES 256
42  Page pt[MAX_PAGES];
43  int page;
44  int record;
45 } AnmDemuxContext;
46 
47 #define LPF_TAG MKTAG('L','P','F',' ')
48 #define ANIM_TAG MKTAG('A','N','I','M')
49 
50 static int probe(AVProbeData *p)
51 {
52  /* verify tags and video dimensions */
53  if (AV_RL32(&p->buf[0]) == LPF_TAG &&
54  AV_RL32(&p->buf[16]) == ANIM_TAG &&
55  AV_RL16(&p->buf[20]) && AV_RL16(&p->buf[22]))
56  return AVPROBE_SCORE_MAX;
57  return 0;
58 }
59 
63 static int find_record(const AnmDemuxContext *anm, int record)
64 {
65  int i;
66 
67  if (record >= anm->nb_records)
68  return AVERROR_EOF;
69 
70  for (i = 0; i < MAX_PAGES; i++) {
71  const Page *p = &anm->pt[i];
72  if (p->nb_records > 0 && record >= p->base_record && record < p->base_record + p->nb_records)
73  return i;
74  }
75 
76  return AVERROR_INVALIDDATA;
77 }
78 
81 {
82  AnmDemuxContext *anm = s->priv_data;
83  AVIOContext *pb = s->pb;
84  AVStream *st;
85  int i, ret;
86 
87  avio_skip(pb, 4); /* magic number */
88  if (avio_rl16(pb) != MAX_PAGES) {
89  av_log_ask_for_sample(s, "max_pages != " AV_STRINGIFY(MAX_PAGES) "\n");
90  return AVERROR_INVALIDDATA;
91  }
92 
93  anm->nb_pages = avio_rl16(pb);
94  anm->nb_records = avio_rl32(pb);
95  avio_skip(pb, 2); /* max records per page */
96  anm->page_table_offset = avio_rl16(pb);
97  if (avio_rl32(pb) != ANIM_TAG)
98  return AVERROR_INVALIDDATA;
99 
100  /* video stream */
101  st = avformat_new_stream(s, NULL);
102  if (!st)
103  return AVERROR(ENOMEM);
105  st->codec->codec_id = CODEC_ID_ANM;
106  st->codec->codec_tag = 0; /* no fourcc */
107  st->codec->width = avio_rl16(pb);
108  st->codec->height = avio_rl16(pb);
109  if (avio_r8(pb) != 0)
110  goto invalid;
111  avio_skip(pb, 1); /* frame rate multiplier info */
112 
113  /* ignore last delta record (used for looping) */
114  if (avio_r8(pb)) /* has_last_delta */
115  anm->nb_records = FFMAX(anm->nb_records - 1, 0);
116 
117  avio_skip(pb, 1); /* last_delta_valid */
118 
119  if (avio_r8(pb) != 0)
120  goto invalid;
121 
122  if (avio_r8(pb) != 1)
123  goto invalid;
124 
125  avio_skip(pb, 1); /* other recs per frame */
126 
127  if (avio_r8(pb) != 1)
128  goto invalid;
129 
130  avio_skip(pb, 32); /* record_types */
131  st->nb_frames = avio_rl32(pb);
132  avpriv_set_pts_info(st, 64, 1, avio_rl16(pb));
133  avio_skip(pb, 58);
134 
135  /* color cycling and palette data */
136  st->codec->extradata_size = 16*8 + 4*256;
138  if (!st->codec->extradata) {
139  ret = AVERROR(ENOMEM);
140  goto fail;
141  }
142  ret = avio_read(pb, st->codec->extradata, st->codec->extradata_size);
143  if (ret < 0)
144  goto fail;
145 
146  /* read page table */
147  ret = avio_seek(pb, anm->page_table_offset, SEEK_SET);
148  if (ret < 0)
149  goto fail;
150 
151  for (i = 0; i < MAX_PAGES; i++) {
152  Page *p = &anm->pt[i];
153  p->base_record = avio_rl16(pb);
154  p->nb_records = avio_rl16(pb);
155  p->size = avio_rl16(pb);
156  }
157 
158  /* find page of first frame */
159  anm->page = find_record(anm, 0);
160  if (anm->page < 0) {
161  ret = anm->page;
162  goto fail;
163  }
164 
165  anm->record = -1;
166  return 0;
167 
168 invalid:
170  ret = AVERROR_INVALIDDATA;
171 
172 fail:
173  return ret;
174 }
175 
177  AVPacket *pkt)
178 {
179  AnmDemuxContext *anm = s->priv_data;
180  AVIOContext *pb = s->pb;
181  Page *p;
182  int tmp, record_size;
183 
184  if (s->pb->eof_reached)
185  return AVERROR(EIO);
186 
187  if (anm->page < 0)
188  return anm->page;
189 
190 repeat:
191  p = &anm->pt[anm->page];
192 
193  /* parse page header */
194  if (anm->record < 0) {
195  avio_seek(pb, anm->page_table_offset + MAX_PAGES*6 + (anm->page<<16), SEEK_SET);
196  avio_skip(pb, 8 + 2*p->nb_records);
197  anm->record = 0;
198  }
199 
200  /* if we have fetched all records in this page, then find the
201  next page and repeat */
202  if (anm->record >= p->nb_records) {
203  anm->page = find_record(anm, p->base_record + p->nb_records);
204  if (anm->page < 0)
205  return anm->page;
206  anm->record = -1;
207  goto repeat;
208  }
209 
210  /* fetch record size */
211  tmp = avio_tell(pb);
212  avio_seek(pb, anm->page_table_offset + MAX_PAGES*6 + (anm->page<<16) +
213  8 + anm->record * 2, SEEK_SET);
214  record_size = avio_rl16(pb);
215  avio_seek(pb, tmp, SEEK_SET);
216 
217  /* fetch record */
218  pkt->size = av_get_packet(s->pb, pkt, record_size);
219  if (pkt->size < 0)
220  return pkt->size;
221  if (p->base_record + anm->record == 0)
222  pkt->flags |= AV_PKT_FLAG_KEY;
223 
224  anm->record++;
225  return 0;
226 }
227 
229  .name = "anm",
230  .long_name = NULL_IF_CONFIG_SMALL("Deluxe Paint Animation"),
231  .priv_data_size = sizeof(AnmDemuxContext),
232  .read_probe = probe,
235 };