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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 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  * Deluxe Paint Animation demuxer
25  */
26 
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; /**< total pages in file */
39  unsigned int nb_records; /**< total records in file */
41 #define MAX_PAGES 256 /**< Deluxe Paint hardcoded value */
42  Page pt[MAX_PAGES]; /**< page table */
43  int page; /**< current page (or AVERROR_xxx code) */
44  int record; /**< current record (with in page) */
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 
60 /**
61  * @return page containing the requested record or AVERROR_XXX
62  */
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 
80 {
81  AnmDemuxContext *anm = s->priv_data;
82  AVIOContext *pb = s->pb;
83  AVStream *st;
84  int i, ret;
85 
86  avio_skip(pb, 4); /* magic number */
87  if (avio_rl16(pb) != MAX_PAGES) {
88  avpriv_request_sample(s, "max_pages != " AV_STRINGIFY(MAX_PAGES));
89  return AVERROR_PATCHWELCOME;
90  }
91 
92  anm->nb_pages = avio_rl16(pb);
93  anm->nb_records = avio_rl32(pb);
94  avio_skip(pb, 2); /* max records per page */
95  anm->page_table_offset = avio_rl16(pb);
96  if (avio_rl32(pb) != ANIM_TAG)
97  return AVERROR_INVALIDDATA;
98 
99  /* video stream */
100  st = avformat_new_stream(s, NULL);
101  if (!st)
102  return AVERROR(ENOMEM);
105  st->codec->codec_tag = 0; /* no fourcc */
106  st->codec->width = avio_rl16(pb);
107  st->codec->height = avio_rl16(pb);
108  if (avio_r8(pb) != 0)
109  goto invalid;
110  avio_skip(pb, 1); /* frame rate multiplier info */
111 
112  /* ignore last delta record (used for looping) */
113  if (avio_r8(pb)) /* has_last_delta */
114  anm->nb_records = FFMAX(anm->nb_records - 1, 0);
115 
116  avio_skip(pb, 1); /* last_delta_valid */
117 
118  if (avio_r8(pb) != 0)
119  goto invalid;
120 
121  if (avio_r8(pb) != 1)
122  goto invalid;
123 
124  avio_skip(pb, 1); /* other recs per frame */
125 
126  if (avio_r8(pb) != 1)
127  goto invalid;
128 
129  avio_skip(pb, 32); /* record_types */
130  st->nb_frames = avio_rl32(pb);
131  avpriv_set_pts_info(st, 64, 1, avio_rl16(pb));
132  avio_skip(pb, 58);
133 
134  /* color cycling and palette data */
135  st->codec->extradata_size = 16*8 + 4*256;
137  if (!st->codec->extradata) {
138  return AVERROR(ENOMEM);
139  }
140  ret = avio_read(pb, st->codec->extradata, st->codec->extradata_size);
141  if (ret < 0)
142  return ret;
143 
144  /* read page table */
145  ret = avio_seek(pb, anm->page_table_offset, SEEK_SET);
146  if (ret < 0)
147  return ret;
148 
149  for (i = 0; i < MAX_PAGES; i++) {
150  Page *p = &anm->pt[i];
151  p->base_record = avio_rl16(pb);
152  p->nb_records = avio_rl16(pb);
153  p->size = avio_rl16(pb);
154  }
155 
156  /* find page of first frame */
157  anm->page = find_record(anm, 0);
158  if (anm->page < 0) {
159  return anm->page;
160  }
161 
162  anm->record = -1;
163  return 0;
164 
165 invalid:
166  avpriv_request_sample(s, "Invalid header element");
167  return AVERROR_PATCHWELCOME;
168 }
169 
171  AVPacket *pkt)
172 {
173  AnmDemuxContext *anm = s->priv_data;
174  AVIOContext *pb = s->pb;
175  Page *p;
176  int tmp, record_size;
177 
178  if (url_feof(s->pb))
179  return AVERROR(EIO);
180 
181  if (anm->page < 0)
182  return anm->page;
183 
184 repeat:
185  p = &anm->pt[anm->page];
186 
187  /* parse page header */
188  if (anm->record < 0) {
189  avio_seek(pb, anm->page_table_offset + MAX_PAGES*6 + (anm->page<<16), SEEK_SET);
190  avio_skip(pb, 8 + 2*p->nb_records);
191  anm->record = 0;
192  }
193 
194  /* if we have fetched all records in this page, then find the
195  next page and repeat */
196  if (anm->record >= p->nb_records) {
197  anm->page = find_record(anm, p->base_record + p->nb_records);
198  if (anm->page < 0)
199  return anm->page;
200  anm->record = -1;
201  goto repeat;
202  }
203 
204  /* fetch record size */
205  tmp = avio_tell(pb);
206  avio_seek(pb, anm->page_table_offset + MAX_PAGES*6 + (anm->page<<16) +
207  8 + anm->record * 2, SEEK_SET);
208  record_size = avio_rl16(pb);
209  avio_seek(pb, tmp, SEEK_SET);
210 
211  /* fetch record */
212  pkt->size = av_get_packet(s->pb, pkt, record_size);
213  if (pkt->size < 0)
214  return pkt->size;
215  if (p->base_record + anm->record == 0)
216  pkt->flags |= AV_PKT_FLAG_KEY;
217 
218  anm->record++;
219  return 0;
220 }
221 
223  .name = "anm",
224  .long_name = NULL_IF_CONFIG_SMALL("Deluxe Paint Animation"),
225  .priv_data_size = sizeof(AnmDemuxContext),
226  .read_probe = probe,
229 };