/*

 * Alias PIX image demuxer

 * Copyright (c) 2014 Michael Niedermayer

 *

 * 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

 */

#include "demux.h"

#include "img2.h"

#include "libavcodec/bytestream.h"

static int alias_pix_read_probe(const AVProbeData *p)

{

    const uint8_t *b = p->buf;

    const uint8_t *end = b + p->buf_size;

    int width  = bytestream_get_be16(&b);

    int height = bytestream_get_be16(&b);

    av_unused int ox = bytestream_get_be16(&b);

    av_unused int oy = bytestream_get_be16(&b);

    int bpp    = bytestream_get_be16(&b);

    int x, y;

    if (!width || !height)

        return 0;

    if (bpp != 24 && bpp != 8)

        return 0;

    for (y=0; y<2 && y<height; y++) {

        for (x=0; x<width; ) {

            int count = *b++;

            if (count == 0 || x + count > width)

                return 0;

            if (b > end)

                return AVPROBE_SCORE_MAX / 8;

            b += bpp / 8;

            x += count;

        }

    }

    return AVPROBE_SCORE_EXTENSION + 1;

}

static const AVClass image2_alias_pix_class = {

    .class_name = "alias_pix demuxer",

    .item_name  = av_default_item_name,

    .option     = ff_img_options,

    .version    = LIBAVUTIL_VERSION_INT,

};

const FFInputFormat ff_image2_alias_pix_demuxer = {

    .p.name         = "alias_pix",

    .p.long_name    = NULL_IF_CONFIG_SMALL("Alias/Wavefront PIX image"),

    .p.priv_class   = &image2_alias_pix_class,

    .priv_data_size = sizeof(VideoDemuxData),

    .read_probe     = alias_pix_read_probe,

    .read_header    = ff_img_read_header,

    .read_packet    = ff_img_read_packet,

    .raw_codec_id   = AV_CODEC_ID_ALIAS_PIX,

};