PeerStreamer

/*

 * Delphine Software International CIN File Demuxer

 * Copyright (c) 2006 Gregory Montoir (cyx@users.sourceforge.net)

 *

 * 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

 */

/**

 * @file

 * Delphine Software International CIN file demuxer

 */

#include "libavutil/intreadwrite.h"

#include "avformat.h"

typedef struct CinFileHeader {

    int video_frame_size;

    int video_frame_width;

    int video_frame_height;

    int audio_frequency;

    int audio_bits;

    int audio_stereo;

    int audio_frame_size;

} CinFileHeader;

typedef struct CinFrameHeader {

    int audio_frame_type;

    int video_frame_type;

    int pal_colors_count;

    int audio_frame_size;

    int video_frame_size;

} CinFrameHeader;

typedef struct CinDemuxContext {

    int audio_stream_index;

    int video_stream_index;

    CinFileHeader file_header;

    int64_t audio_stream_pts;

    int64_t video_stream_pts;

    CinFrameHeader frame_header;

    int audio_buffer_size;

} CinDemuxContext;

static int cin_probe(AVProbeData *p)

{

    /* header starts with this special marker */

    if (AV_RL32(&p->buf[0]) != 0x55AA0000)

        return 0;

    /* for accuracy, check some header field values */

    if (AV_RL32(&p->buf[12]) != 22050 || p->buf[16] != 16 || p->buf[17] != 0)

        return 0;

    return AVPROBE_SCORE_MAX;

}

static int cin_read_file_header(CinDemuxContext *cin, AVIOContext *pb) {

    CinFileHeader *hdr = &cin->file_header;

    if (avio_rl32(pb) != 0x55AA0000)

        return AVERROR_INVALIDDATA;

    hdr->video_frame_size   = avio_rl32(pb);

    hdr->video_frame_width  = avio_rl16(pb);

    hdr->video_frame_height = avio_rl16(pb);

    hdr->audio_frequency    = avio_rl32(pb);

    hdr->audio_bits         = avio_r8(pb);

    hdr->audio_stereo       = avio_r8(pb);

    hdr->audio_frame_size   = avio_rl16(pb);

    if (hdr->audio_frequency != 22050 || hdr->audio_bits != 16 || hdr->audio_stereo != 0)

        return AVERROR_INVALIDDATA;

    return 0;

}

static int cin_read_header(AVFormatContext *s, AVFormatParameters *ap)

{

    int rc;

    CinDemuxContext *cin = s->priv_data;

    CinFileHeader *hdr = &cin->file_header;

    AVIOContext *pb = s->pb;

    AVStream *st;

    rc = cin_read_file_header(cin, pb);

    if (rc)

        return rc;

    cin->video_stream_pts = 0;

    cin->audio_stream_pts = 0;

    cin->audio_buffer_size = 0;

    /* initialize the video decoder stream */

    st = av_new_stream(s, 0);

    if (!st)

        return AVERROR(ENOMEM);

    av_set_pts_info(st, 32, 1, 12);

    cin->video_stream_index = st->index;

    st->codec->codec_type = AVMEDIA_TYPE_VIDEO;

    st->codec->codec_id = CODEC_ID_DSICINVIDEO;

    st->codec->codec_tag = 0;  /* no fourcc */

    st->codec->width = hdr->video_frame_width;

    st->codec->height = hdr->video_frame_height;

    /* initialize the audio decoder stream */

    st = av_new_stream(s, 0);

    if (!st)

        return AVERROR(ENOMEM);

    av_set_pts_info(st, 32, 1, 22050);

    cin->audio_stream_index = st->index;

    st->codec->codec_type = AVMEDIA_TYPE_AUDIO;

    st->codec->codec_id = CODEC_ID_DSICINAUDIO;

    st->codec->codec_tag = 0;  /* no tag */

    st->codec->channels = 1;

    st->codec->sample_rate = 22050;

    st->codec->bits_per_coded_sample = 16;

    st->codec->bit_rate = st->codec->sample_rate * st->codec->bits_per_coded_sample * st->codec->channels;

    st->codec->block_align = st->codec->channels * st->codec->bits_per_coded_sample;

    return 0;

}

static int cin_read_frame_header(CinDemuxContext *cin, AVIOContext *pb) {

    CinFrameHeader *hdr = &cin->frame_header;

    hdr->video_frame_type = avio_r8(pb);

    hdr->audio_frame_type = avio_r8(pb);

    hdr->pal_colors_count = avio_rl16(pb);

    hdr->video_frame_size = avio_rl32(pb);

    hdr->audio_frame_size = avio_rl32(pb);

    if (pb->eof_reached || pb->error)

        return AVERROR(EIO);

    if (avio_rl32(pb) != 0xAA55AA55)

        return AVERROR_INVALIDDATA;

    return 0;

}

static int cin_read_packet(AVFormatContext *s, AVPacket *pkt)

{

    CinDemuxContext *cin = s->priv_data;

    AVIOContext *pb = s->pb;

    CinFrameHeader *hdr = &cin->frame_header;

    int rc, palette_type, pkt_size;

    int ret;

    if (cin->audio_buffer_size == 0) {

        rc = cin_read_frame_header(cin, pb);

        if (rc)

            return rc;

        if ((int16_t)hdr->pal_colors_count < 0) {

            hdr->pal_colors_count = -(int16_t)hdr->pal_colors_count;

            palette_type = 1;

        } else {

            palette_type = 0;

        }

        /* palette and video packet */

        pkt_size = (palette_type + 3) * hdr->pal_colors_count + hdr->video_frame_size;

        ret = av_new_packet(pkt, 4 + pkt_size);

        if (ret < 0)

            return ret;

        pkt->stream_index = cin->video_stream_index;

        pkt->pts = cin->video_stream_pts++;

        pkt->data[0] = palette_type;

        pkt->data[1] = hdr->pal_colors_count & 0xFF;

        pkt->data[2] = hdr->pal_colors_count >> 8;

        pkt->data[3] = hdr->video_frame_type;

        ret = avio_read(pb, &pkt->data[4], pkt_size);

        if (ret < 0) {

            av_free_packet(pkt);

            return ret;

        }

        if (ret < pkt_size)

            av_shrink_packet(pkt, 4 + ret);

        /* sound buffer will be processed on next read_packet() call */

        cin->audio_buffer_size = hdr->audio_frame_size;

        return 0;

    }

    /* audio packet */

    ret = av_get_packet(pb, pkt, cin->audio_buffer_size);

    if (ret < 0)

        return ret;

    pkt->stream_index = cin->audio_stream_index;

    pkt->pts = cin->audio_stream_pts;

    cin->audio_stream_pts += cin->audio_buffer_size * 2 / cin->file_header.audio_frame_size;

    cin->audio_buffer_size = 0;

    return 0;

}

AVInputFormat ff_dsicin_demuxer = {

    "dsicin",

    NULL_IF_CONFIG_SMALL("Delphine Software International CIN format"),

    sizeof(CinDemuxContext),

    cin_probe,

    cin_read_header,

    cin_read_packet,

};