1/*
2 * Alias PIX image demuxer
3 * Copyright (c) 2014 Michael Niedermayer
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#include "img2.h"
23#include "libavcodec/bytestream.h"
24
25static int alias_pix_read_probe(const AVProbeData *p)
26{
27    const uint8_t *b = p->buf;
28    const uint8_t *end = b + p->buf_size;
29    int width  = bytestream_get_be16(&b);
30    int height = bytestream_get_be16(&b);
31    av_unused int ox = bytestream_get_be16(&b);
32    av_unused int oy = bytestream_get_be16(&b);
33    int bpp    = bytestream_get_be16(&b);
34    int x, y;
35
36    if (!width || !height)
37        return 0;
38
39    if (bpp != 24 && bpp != 8)
40        return 0;
41
42    for (y=0; y<2 && y<height; y++) {
43        for (x=0; x<width; ) {
44            int count = *b++;
45            if (count == 0 || x + count > width)
46                return 0;
47            if (b > end)
48                return AVPROBE_SCORE_MAX / 8;
49            b += bpp / 8;
50            x += count;
51        }
52    }
53
54    return AVPROBE_SCORE_EXTENSION + 1;
55}
56
57static const AVClass image2_alias_pix_class = {
58    .class_name = "alias_pix demuxer",
59    .item_name  = av_default_item_name,
60    .option     = ff_img_options,
61    .version    = LIBAVUTIL_VERSION_INT,
62};
63
64const AVInputFormat ff_image2_alias_pix_demuxer = {
65    .name           = "alias_pix",
66    .long_name      = NULL_IF_CONFIG_SMALL("Alias/Wavefront PIX image"),
67    .priv_data_size = sizeof(VideoDemuxData),
68    .read_probe     = alias_pix_read_probe,
69    .read_header    = ff_img_read_header,
70    .read_packet    = ff_img_read_packet,
71    .raw_codec_id   = AV_CODEC_ID_ALIAS_PIX,
72    .priv_class     = &image2_alias_pix_class,
73};
74