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 "internal.h"
  30
  31 typedef struct Page {
  32     int base_record;
  33     unsigned int nb_records;
  34     int size;
  35 } Page;
  36
  37 typedef struct AnmDemuxContext {
  38     unsigned int nb_pages;    /**< total pages in file */
  39     unsigned int nb_records;  /**< total records in file */
  40     int page_table_offset;
  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) */
  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(const 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
  79 static int read_header(AVFormatContext *s)
  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);
 103     st->codecpar->codec_type = AVMEDIA_TYPE_VIDEO;
 104     st->codecpar->codec_id   = AV_CODEC_ID_ANM;
 105     st->codecpar->codec_tag  = 0; /* no fourcc */
 106     st->codecpar->width      = avio_rl16(pb);
 107     st->codecpar->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     ret = ff_get_extradata(s, st->codecpar, s->pb, 16*8 + 4*256);
 136     if (ret < 0)
 137         return ret;
 138
 139     /* read page table */
 140     ret = avio_seek(pb, anm->page_table_offset, SEEK_SET);
 141     if (ret < 0)
 142         return ret;
 143
 144     for (i = 0; i < MAX_PAGES; i++) {
 145         Page *p = &anm->pt[i];
 146         p->base_record = avio_rl16(pb);
 147         p->nb_records  = avio_rl16(pb);
 148         p->size        = avio_rl16(pb);
 149     }
 150
 151     /* find page of first frame */
 152     anm->page = find_record(anm, 0);
 153     if (anm->page < 0) {
 154         return anm->page;
 155     }
 156
 157     anm->record = -1;
 158     return 0;
 159
 160 invalid:
 161     avpriv_request_sample(s, "Invalid header element");
 162     return AVERROR_PATCHWELCOME;
 163 }
 164
 165 static int read_packet(AVFormatContext *s,
 166                        AVPacket *pkt)
 167 {
 168     AnmDemuxContext *anm = s->priv_data;
 169     AVIOContext *pb = s->pb;
 170     Page *p;
 171     int tmp, record_size;
 172
 173     if (avio_feof(s->pb))
 174         return AVERROR(EIO);
 175
 176     if (anm->page < 0)
 177         return anm->page;
 178
 179 repeat:
 180     p = &anm->pt[anm->page];
 181
 182     /* parse page header */
 183     if (anm->record < 0) {
 184         avio_seek(pb, anm->page_table_offset + MAX_PAGES*6 + (anm->page<<16), SEEK_SET);
 185         avio_skip(pb, 8 + 2*p->nb_records);
 186         anm->record = 0;
 187     }
 188
 189     /* if we have fetched all records in this page, then find the
 190        next page and repeat */
 191     if (anm->record >= p->nb_records) {
 192         anm->page = find_record(anm, p->base_record + p->nb_records);
 193         if (anm->page < 0)
 194             return anm->page;
 195         anm->record = -1;
 196         goto repeat;
 197     }
 198
 199     /* fetch record size */
 200     tmp = avio_tell(pb);
 201     avio_seek(pb, anm->page_table_offset + MAX_PAGES*6 + (anm->page<<16) +
 202               8 + anm->record * 2, SEEK_SET);
 203     record_size = avio_rl16(pb);
 204     avio_seek(pb, tmp, SEEK_SET);
 205
 206     /* fetch record */
 207     pkt->size = av_get_packet(s->pb, pkt, record_size);
 208     if (pkt->size < 0)
 209         return pkt->size;
 210     if (p->base_record + anm->record == 0)
 211         pkt->flags |= AV_PKT_FLAG_KEY;
 212
 213     anm->record++;
 214     return 0;
 215 }
 216
 217 AVInputFormat ff_anm_demuxer = {
 218     .name           = "anm",
 219     .long_name      = NULL_IF_CONFIG_SMALL("Deluxe Paint Animation"),
 220     .priv_data_size = sizeof(AnmDemuxContext),
 221     .read_probe     = probe,
 222     .read_header    = read_header,
 223     .read_packet    = read_packet,
 224 };