libavformat/anm.c

   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 "demux.h"
  30 #include "internal.h"
  31
  32 typedef struct Page {
  33     int base_record;
  34     unsigned int nb_records;
  35     int size;
  36 } Page;
  37
  38 typedef struct AnmDemuxContext {
  39     unsigned int nb_pages;    /**< total pages in file */
  40     unsigned int nb_records;  /**< total records in file */
  41     int page_table_offset;
  42 #define MAX_PAGES  256        /**< Deluxe Paint hardcoded value */
  43     Page pt[MAX_PAGES];       /**< page table */
  44     int page;                 /**< current page (or AVERROR_xxx code) */
  45     int record;               /**< current record (with in page) */
  46 } AnmDemuxContext;
  47
  48 #define LPF_TAG  MKTAG('L','P','F',' ')
  49 #define ANIM_TAG MKTAG('A','N','I','M')
  50
  51 static int probe(const AVProbeData *p)
  52 {
  53     /* verify tags and video dimensions */
  54     if (AV_RL32(&p->buf[0])  == LPF_TAG &&
  55         AV_RL32(&p->buf[16]) == ANIM_TAG &&
  56         AV_RL16(&p->buf[20]) && AV_RL16(&p->buf[22]))
  57         return AVPROBE_SCORE_MAX;
  58     return 0;
  59 }
  60
  61 /**
  62  * @return page containing the requested record or AVERROR_XXX
  63  */
  64 static int find_record(const AnmDemuxContext *anm, int record)
  65 {
  66     int i;
  67
  68     if (record >= anm->nb_records)
  69         return AVERROR_EOF;
  70
  71     for (i = 0; i < MAX_PAGES; i++) {
  72         const Page *p = &anm->pt[i];
  73         if (p->nb_records > 0 && record >= p->base_record && record < p->base_record + p->nb_records)
  74             return i;
  75     }
  76
  77     return AVERROR_INVALIDDATA;
  78 }
  79
  80 static int read_header(AVFormatContext *s)
  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         avpriv_request_sample(s, "max_pages != " AV_STRINGIFY(MAX_PAGES));
  90         return AVERROR_PATCHWELCOME;
  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);
 104     st->codecpar->codec_type = AVMEDIA_TYPE_VIDEO;
 105     st->codecpar->codec_id   = AV_CODEC_ID_ANM;
 106     st->codecpar->codec_tag  = 0; /* no fourcc */
 107     st->codecpar->width      = avio_rl16(pb);
 108     st->codecpar->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     ret = ff_get_extradata(s, st->codecpar, s->pb, 16*8 + 4*256);
 137     if (ret < 0)
 138         return ret;
 139
 140     /* read page table */
 141     ret = avio_seek(pb, anm->page_table_offset, SEEK_SET);
 142     if (ret < 0)
 143         return ret;
 144
 145     for (i = 0; i < MAX_PAGES; i++) {
 146         Page *p = &anm->pt[i];
 147         p->base_record = avio_rl16(pb);
 148         p->nb_records  = avio_rl16(pb);
 149         p->size        = avio_rl16(pb);
 150     }
 151
 152     /* find page of first frame */
 153     anm->page = find_record(anm, 0);
 154     if (anm->page < 0) {
 155         return anm->page;
 156     }
 157
 158     anm->record = -1;
 159     return 0;
 160
 161 invalid:
 162     avpriv_request_sample(s, "Invalid header element");
 163     return AVERROR_PATCHWELCOME;
 164 }
 165
 166 static int read_packet(AVFormatContext *s,
 167                        AVPacket *pkt)
 168 {
 169     AnmDemuxContext *anm = s->priv_data;
 170     AVIOContext *pb = s->pb;
 171     Page *p;
 172     int tmp, record_size;
 173
 174     if (avio_feof(s->pb))
 175         return AVERROR_EOF;
 176
 177     if (anm->page < 0)
 178         return anm->page;
 179
 180 repeat:
 181     p = &anm->pt[anm->page];
 182
 183     /* parse page header */
 184     if (anm->record < 0) {
 185         avio_seek(pb, anm->page_table_offset + MAX_PAGES*6 + (anm->page<<16), SEEK_SET);
 186         avio_skip(pb, 8 + 2*p->nb_records);
 187         anm->record = 0;
 188     }
 189
 190     /* if we have fetched all records in this page, then find the
 191        next page and repeat */
 192     if (anm->record >= p->nb_records) {
 193         anm->page = find_record(anm, p->base_record + p->nb_records);
 194         if (anm->page < 0)
 195             return anm->page;
 196         anm->record = -1;
 197         goto repeat;
 198     }
 199
 200     /* fetch record size */
 201     tmp = avio_tell(pb);
 202     avio_seek(pb, anm->page_table_offset + MAX_PAGES*6 + (anm->page<<16) +
 203               8 + anm->record * 2, SEEK_SET);
 204     record_size = avio_rl16(pb);
 205     avio_seek(pb, tmp, SEEK_SET);
 206
 207     /* fetch record */
 208     pkt->size = av_get_packet(s->pb, pkt, record_size);
 209     if (pkt->size < 0)
 210         return pkt->size;
 211     if (p->base_record + anm->record == 0)
 212         pkt->flags |= AV_PKT_FLAG_KEY;
 213
 214     anm->record++;
 215     return 0;
 216 }
 217
 218 const FFInputFormat ff_anm_demuxer = {
 219     .p.name         = "anm",
 220     .p.long_name    = NULL_IF_CONFIG_SMALL("Deluxe Paint Animation"),
 221     .priv_data_size = sizeof(AnmDemuxContext),
 222     .read_probe     = probe,
 223     .read_header    = read_header,
 224     .read_packet    = read_packet,
 225 };