hnm.c 5.45 KB
Newer Older
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204
/*
 * Cryo Interactive Entertainment HNM4 demuxer
 *
 * Copyright (c) 2012 David Kment
 *
 * This file is part of Libav.
 *
 * Libav 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.
 *
 * Libav 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 Libav; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
 */

#include "libavutil/intreadwrite.h"
#include "avformat.h"
#include "internal.h"

#define HNM4_TAG MKTAG('H', 'N', 'M', '4')

#define HNM4_SAMPLE_RATE 22050
#define HNM4_FRAME_FPS 24

#define HNM4_CHUNK_ID_PL 19536
#define HNM4_CHUNK_ID_IZ 23113
#define HNM4_CHUNK_ID_IU 21833
#define HNM4_CHUNK_ID_SD 17491

typedef struct Hnm4DemuxContext {
    uint8_t version;
    uint16_t width;
    uint16_t height;
    uint32_t filesize;
    uint32_t frames;
    uint32_t taboffset;
    uint16_t bits;
    uint16_t channels;
    uint32_t framesize;
    uint32_t currentframe;
    int64_t pts;
    uint32_t superchunk_remaining;
    AVPacket vpkt;
} Hnm4DemuxContext;

static int hnm_probe(AVProbeData *p)
{
    if (p->buf_size < 4)
        return 0;

    // check for HNM4 header.
    // currently only HNM v4/v4A is supported
    if (AV_RL32(&p->buf[0]) == HNM4_TAG)
        return AVPROBE_SCORE_MAX;

    return 0;
}

static int hnm_read_header(AVFormatContext *s)
{
    Hnm4DemuxContext *hnm = s->priv_data;
    AVIOContext *pb = s->pb;
    AVStream *vst;

    /* default context members */
    hnm->pts = 0;
    av_init_packet(&hnm->vpkt);
    hnm->vpkt.data = NULL;
    hnm->vpkt.size = 0;

    hnm->superchunk_remaining = 0;

    avio_skip(pb, 8);
    hnm->width     = avio_rl16(pb);
    hnm->height    = avio_rl16(pb);
    hnm->filesize  = avio_rl32(pb);
    hnm->frames    = avio_rl32(pb);
    hnm->taboffset = avio_rl32(pb);
    hnm->bits      = avio_rl16(pb);
    hnm->channels  = avio_rl16(pb);
    hnm->framesize = avio_rl32(pb);
    avio_skip(pb, 32);

    hnm->currentframe = 0;

    if (hnm->width  < 320 || hnm->width  > 640 ||
        hnm->height < 150 || hnm->height > 480) {
        av_log(s, AV_LOG_ERROR,
               "invalid resolution: %ux%u\n", hnm->width, hnm->height);
        return AVERROR_INVALIDDATA;
    }

    // TODO: find a better way to detect HNM4A
    if (hnm->width == 640)
        hnm->version = 0x4a;
    else
        hnm->version = 0x40;

    if (!(vst = avformat_new_stream(s, NULL)))
        return AVERROR(ENOMEM);

    vst->codec->codec_type = AVMEDIA_TYPE_VIDEO;
    vst->codec->codec_id   = AV_CODEC_ID_HNM4_VIDEO;
    vst->codec->codec_tag  = 0;
    vst->codec->width      = hnm->width;
    vst->codec->height     = hnm->height;
    vst->codec->extradata  = av_mallocz(1);

    vst->codec->extradata_size = 1;
    memcpy(vst->codec->extradata, &hnm->version, 1);

    vst->start_time = 0;

    avpriv_set_pts_info(vst, 33, 1, HNM4_FRAME_FPS);

    return 0;
}

static int hnm_read_packet(AVFormatContext *s, AVPacket *pkt)
{
    Hnm4DemuxContext *hnm = s->priv_data;
    AVIOContext *pb = s->pb;
    int ret = 0;

    uint32_t superchunk_size, chunk_size;
    uint16_t chunk_id;

    if (hnm->currentframe == hnm->frames || pb->eof_reached)
        return AVERROR_EOF;

    if (hnm->superchunk_remaining == 0) {
        /* parse next superchunk */
        superchunk_size = avio_rl24(pb);
        avio_skip(pb, 1);

        hnm->superchunk_remaining = superchunk_size - 4;
    }

    chunk_size = avio_rl24(pb);
    avio_skip(pb, 1);
    chunk_id = avio_rl16(pb);
    avio_skip(pb, 2);

    if (chunk_size > hnm->superchunk_remaining) {
        av_log(s, AV_LOG_ERROR, "invalid chunk size: %u, offset: %u\n",
               chunk_size, (int) avio_tell(pb));
        avio_skip(pb, hnm->superchunk_remaining - 8);
        hnm->superchunk_remaining = 0;
    }

    switch (chunk_id) {
    case HNM4_CHUNK_ID_PL:
    case HNM4_CHUNK_ID_IZ:
    case HNM4_CHUNK_ID_IU:
        avio_seek(pb, -8, SEEK_CUR);
        ret += av_get_packet(pb, pkt, chunk_size);
        hnm->superchunk_remaining -= chunk_size;
        if (chunk_id == HNM4_CHUNK_ID_IZ || chunk_id == HNM4_CHUNK_ID_IU)
            hnm->currentframe++;
        break;

    case HNM4_CHUNK_ID_SD:
        avio_skip(pb, chunk_size - 8);
        hnm->superchunk_remaining -= chunk_size;
        break;

    default:
        av_log(s, AV_LOG_WARNING, "unknown chunk found: %d, offset: %d\n",
               chunk_id, (int) avio_tell(pb));
        avio_skip(pb, chunk_size - 8);
        hnm->superchunk_remaining -= chunk_size;
        break;
    }

    return ret;
}

static int hnm_read_close(AVFormatContext *s)
{
    Hnm4DemuxContext *hnm = s->priv_data;

    if (hnm->vpkt.size > 0)
        av_free_packet(&hnm->vpkt);

    return 0;
}

AVInputFormat ff_hnm_demuxer = {
    .name           = "hnm",
    .long_name      = NULL_IF_CONFIG_SMALL("Cryo HNM v4"),
    .priv_data_size = sizeof(Hnm4DemuxContext),
    .read_probe     = hnm_probe,
    .read_header    = hnm_read_header,
    .read_packet    = hnm_read_packet,
    .read_close     = hnm_read_close,
    .flags          = AVFMT_NO_BYTE_SEEK | AVFMT_NOGENSEARCH | AVFMT_NOBINSEARCH
};