ffmpeg/libavformat/anm.c
Anton Khirnov e356fc57a2 lavf: replace all uses of url_fskip with avio_seek
Signed-off-by: Ronald S. Bultje <rsbultje@gmail.com>
2011-03-01 12:22:16 -05:00

236 lines
6.4 KiB
C

/*
* Deluxe Paint Animation demuxer
* Copyright (c) 2009 Peter Ross
*
* This file is part of FFmpeg.
*
* FFmpeg is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* FFmpeg is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with FFmpeg; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
/**
* @file
* Deluxe Paint Animation demuxer
*/
#include "libavutil/intreadwrite.h"
#include "avformat.h"
typedef struct {
int base_record;
unsigned int nb_records;
int size;
} Page;
typedef struct {
unsigned int nb_pages; /**< total pages in file */
unsigned int nb_records; /**< total records in file */
int page_table_offset;
#define MAX_PAGES 256 /**< Deluxe Paint hardcoded value */
Page pt[MAX_PAGES]; /**< page table */
int page; /**< current page (or AVERROR_xxx code) */
int record; /**< current record (with in page) */
} AnmDemuxContext;
#define LPF_TAG MKTAG('L','P','F',' ')
#define ANIM_TAG MKTAG('A','N','I','M')
static int probe(AVProbeData *p)
{
/* verify tags and video dimensions */
if (AV_RL32(&p->buf[0]) == LPF_TAG &&
AV_RL32(&p->buf[16]) == ANIM_TAG &&
AV_RL16(&p->buf[20]) && AV_RL16(&p->buf[22]))
return AVPROBE_SCORE_MAX;
return 0;
}
/**
* @return page containing the requested record or AVERROR_XXX
*/
static int find_record(const AnmDemuxContext *anm, int record)
{
int i;
if (record >= anm->nb_records)
return AVERROR_EOF;
for (i = 0; i < MAX_PAGES; i++) {
const Page *p = &anm->pt[i];
if (p->nb_records > 0 && record >= p->base_record && record < p->base_record + p->nb_records)
return i;
}
return AVERROR_INVALIDDATA;
}
static int read_header(AVFormatContext *s,
AVFormatParameters *ap)
{
AnmDemuxContext *anm = s->priv_data;
AVIOContext *pb = s->pb;
AVStream *st;
int i, ret;
avio_seek(pb, 4, SEEK_CUR); /* magic number */
if (avio_rl16(pb) != MAX_PAGES) {
av_log_ask_for_sample(s, "max_pages != " AV_STRINGIFY(MAX_PAGES) "\n");
return AVERROR_INVALIDDATA;
}
anm->nb_pages = avio_rl16(pb);
anm->nb_records = avio_rl32(pb);
avio_seek(pb, 2, SEEK_CUR); /* max records per page */
anm->page_table_offset = avio_rl16(pb);
if (avio_rl32(pb) != ANIM_TAG)
return AVERROR_INVALIDDATA;
/* video stream */
st = av_new_stream(s, 0);
if (!st)
return AVERROR(ENOMEM);
st->codec->codec_type = AVMEDIA_TYPE_VIDEO;
st->codec->codec_id = CODEC_ID_ANM;
st->codec->codec_tag = 0; /* no fourcc */
st->codec->width = avio_rl16(pb);
st->codec->height = avio_rl16(pb);
if (avio_r8(pb) != 0)
goto invalid;
avio_seek(pb, 1, SEEK_CUR); /* frame rate multiplier info */
/* ignore last delta record (used for looping) */
if (avio_r8(pb)) /* has_last_delta */
anm->nb_records = FFMAX(anm->nb_records - 1, 0);
avio_seek(pb, 1, SEEK_CUR); /* last_delta_valid */
if (avio_r8(pb) != 0)
goto invalid;
if (avio_r8(pb) != 1)
goto invalid;
avio_seek(pb, 1, SEEK_CUR); /* other recs per frame */
if (avio_r8(pb) != 1)
goto invalid;
avio_seek(pb, 32, SEEK_CUR); /* record_types */
st->nb_frames = avio_rl32(pb);
av_set_pts_info(st, 64, 1, avio_rl16(pb));
avio_seek(pb, 58, SEEK_CUR);
/* color cycling and palette data */
st->codec->extradata_size = 16*8 + 4*256;
st->codec->extradata = av_mallocz(st->codec->extradata_size + FF_INPUT_BUFFER_PADDING_SIZE);
if (!st->codec->extradata) {
ret = AVERROR(ENOMEM);
goto close_and_return;
}
ret = avio_read(pb, st->codec->extradata, st->codec->extradata_size);
if (ret < 0)
goto close_and_return;
/* read page table */
ret = avio_seek(pb, anm->page_table_offset, SEEK_SET);
if (ret < 0)
goto close_and_return;
for (i = 0; i < MAX_PAGES; i++) {
Page *p = &anm->pt[i];
p->base_record = avio_rl16(pb);
p->nb_records = avio_rl16(pb);
p->size = avio_rl16(pb);
}
/* find page of first frame */
anm->page = find_record(anm, 0);
if (anm->page < 0) {
ret = anm->page;
goto close_and_return;
}
anm->record = -1;
return 0;
invalid:
av_log_ask_for_sample(s, NULL);
ret = AVERROR_INVALIDDATA;
close_and_return:
av_close_input_stream(s);
return ret;
}
static int read_packet(AVFormatContext *s,
AVPacket *pkt)
{
AnmDemuxContext *anm = s->priv_data;
AVIOContext *pb = s->pb;
Page *p;
int tmp, record_size;
if (url_feof(s->pb))
return AVERROR(EIO);
if (anm->page < 0)
return anm->page;
repeat:
p = &anm->pt[anm->page];
/* parse page header */
if (anm->record < 0) {
avio_seek(pb, anm->page_table_offset + MAX_PAGES*6 + (anm->page<<16), SEEK_SET);
avio_seek(pb, 8 + 2*p->nb_records, SEEK_CUR);
anm->record = 0;
}
/* if we have fetched all records in this page, then find the
next page and repeat */
if (anm->record >= p->nb_records) {
anm->page = find_record(anm, p->base_record + p->nb_records);
if (anm->page < 0)
return anm->page;
anm->record = -1;
goto repeat;
}
/* fetch record size */
tmp = url_ftell(pb);
avio_seek(pb, anm->page_table_offset + MAX_PAGES*6 + (anm->page<<16) +
8 + anm->record * 2, SEEK_SET);
record_size = avio_rl16(pb);
avio_seek(pb, tmp, SEEK_SET);
/* fetch record */
pkt->size = av_get_packet(s->pb, pkt, record_size);
if (pkt->size < 0)
return pkt->size;
if (p->base_record + anm->record == 0)
pkt->flags |= AV_PKT_FLAG_KEY;
anm->record++;
return 0;
}
AVInputFormat ff_anm_demuxer = {
"anm",
NULL_IF_CONFIG_SMALL("Deluxe Paint Animation"),
sizeof(AnmDemuxContext),
probe,
read_header,
read_packet,
};