PeerStreamer

/*

 * IFF (.iff) file demuxer

 * Copyright (c) 2008 Jaikrishnan Menon <realityman@gmx.net>

 * Copyright (c) 2010 Peter Ross <pross@xvid.org>

 * Copyright (c) 2010 Sebastian Vater <cdgs.basty@googlemail.com>

 *

 * 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

 * IFF file demuxer

 * by Jaikrishnan Menon

 * for more information on the .iff file format, visit:

 * http://wiki.multimedia.cx/index.php?title=IFF

 */

#include "libavutil/intreadwrite.h"

#include "avformat.h"

#define ID_8SVX       MKTAG('8','S','V','X')

#define ID_VHDR       MKTAG('V','H','D','R')

#define ID_ATAK       MKTAG('A','T','A','K')

#define ID_RLSE       MKTAG('R','L','S','E')

#define ID_CHAN       MKTAG('C','H','A','N')

#define ID_PBM        MKTAG('P','B','M',' ')

#define ID_ILBM       MKTAG('I','L','B','M')

#define ID_BMHD       MKTAG('B','M','H','D')

#define ID_CMAP       MKTAG('C','M','A','P')

#define ID_FORM       MKTAG('F','O','R','M')

#define ID_ANNO       MKTAG('A','N','N','O')

#define ID_AUTH       MKTAG('A','U','T','H')

#define ID_CHRS       MKTAG('C','H','R','S')

#define ID_COPYRIGHT  MKTAG('(','c',')',' ')

#define ID_CSET       MKTAG('C','S','E','T')

#define ID_FVER       MKTAG('F','V','E','R')

#define ID_NAME       MKTAG('N','A','M','E')

#define ID_TEXT       MKTAG('T','E','X','T')

#define ID_BODY       MKTAG('B','O','D','Y')

#define ID_ANNO       MKTAG('A','N','N','O')

#define LEFT    2

#define RIGHT   4

#define STEREO  6

#define PACKET_SIZE 1024

typedef enum {

    COMP_NONE,

    COMP_FIB,

    COMP_EXP

} svx8_compression_type;

typedef enum {

    BITMAP_RAW,

    BITMAP_BYTERUN1

} bitmap_compression_type;

typedef struct {

    uint64_t  body_pos;

    uint32_t  body_size;

    uint32_t  sent_bytes;

    uint32_t  audio_frame_count;

} IffDemuxContext;

static void interleave_stereo(const uint8_t *src, uint8_t *dest, int size)

{

    uint8_t *end = dest + size;

    size = size>>1;

    while(dest < end) {

        *dest++ = *src;

        *dest++ = *(src+size);

        src++;

    }

}

/* Metadata string read */

static int get_metadata(AVFormatContext *s,

                        const char *const tag,

                        const unsigned data_size)

{

    uint8_t *buf = ((data_size + 1) == 0) ? NULL : av_malloc(data_size + 1);

    if (!buf)

        return AVERROR(ENOMEM);

    if (avio_read(s->pb, buf, data_size) < 0) {

        av_free(buf);

        return AVERROR(EIO);

    }

    buf[data_size] = 0;

    av_metadata_set2(&s->metadata, tag, buf, AV_METADATA_DONT_STRDUP_VAL);

    return 0;

}

static int iff_probe(AVProbeData *p)

{

    const uint8_t *d = p->buf;

    if ( AV_RL32(d)   == ID_FORM &&

         (AV_RL32(d+8) == ID_8SVX || AV_RL32(d+8) == ID_PBM || AV_RL32(d+8) == ID_ILBM) )

        return AVPROBE_SCORE_MAX;

    return 0;

}

static int iff_read_header(AVFormatContext *s,

                           AVFormatParameters *ap)

{

    IffDemuxContext *iff = s->priv_data;

    AVIOContext *pb = s->pb;

    AVStream *st;

    uint32_t chunk_id, data_size;

    int compression = -1;

    st = av_new_stream(s, 0);

    if (!st)

        return AVERROR(ENOMEM);

    st->codec->channels = 1;

    avio_seek(pb, 8, SEEK_CUR);

    // codec_tag used by ByteRun1 decoder to distinguish progressive (PBM) and interlaced (ILBM) content

    st->codec->codec_tag = avio_rl32(pb);

    while(!pb->eof_reached) {

        uint64_t orig_pos;

        int res;

        const char *metadata_tag = NULL;

        chunk_id = avio_rl32(pb);

        data_size = avio_rb32(pb);

        orig_pos = avio_tell(pb);

        switch(chunk_id) {

        case ID_VHDR:

            st->codec->codec_type = AVMEDIA_TYPE_AUDIO;

            if (data_size < 14)

                return AVERROR_INVALIDDATA;

            avio_seek(pb, 12, SEEK_CUR);

            st->codec->sample_rate = avio_rb16(pb);

            if (data_size >= 16) {

                avio_seek(pb, 1, SEEK_CUR);

                compression        = avio_r8(pb);

            }

            break;

        case ID_BODY:

            iff->body_pos = avio_tell(pb);

            iff->body_size = data_size;

            break;

        case ID_CHAN:

            if (data_size < 4)

                return AVERROR_INVALIDDATA;

            st->codec->channels = (avio_rb32(pb) < 6) ? 1 : 2;

            break;

        case ID_CMAP:

            st->codec->extradata_size = data_size;

            st->codec->extradata      = av_malloc(data_size);

            if (!st->codec->extradata)

                return AVERROR(ENOMEM);

            if (avio_read(pb, st->codec->extradata, data_size) < 0)

                return AVERROR(EIO);

            break;

        case ID_BMHD:

            st->codec->codec_type            = AVMEDIA_TYPE_VIDEO;

            if (data_size <= 8)

                return AVERROR_INVALIDDATA;

            st->codec->width                 = avio_rb16(pb);

            st->codec->height                = avio_rb16(pb);

            avio_seek(pb, 4, SEEK_CUR); // x, y offset

            st->codec->bits_per_coded_sample = avio_r8(pb);

            if (data_size >= 11) {

                avio_seek(pb, 1, SEEK_CUR); // masking

                compression                  = avio_r8(pb);

            }

            if (data_size >= 16) {

                avio_seek(pb, 3, SEEK_CUR); // paddding, transparent

                st->sample_aspect_ratio.num  = avio_r8(pb);

                st->sample_aspect_ratio.den  = avio_r8(pb);

            }

            break;

        case ID_ANNO:

        case ID_TEXT:

            metadata_tag = "comment";

            break;

        case ID_AUTH:

            metadata_tag = "artist";

            break;

        case ID_COPYRIGHT:

            metadata_tag = "copyright";

            break;

        case ID_NAME:

            metadata_tag = "title";

            break;

        }

        if (metadata_tag) {

            if ((res = get_metadata(s, metadata_tag, data_size)) < 0) {

                av_log(s, AV_LOG_ERROR, "cannot allocate metadata tag %s!", metadata_tag);

                return res;

            }

        }

        avio_seek(pb, data_size - (avio_tell(pb) - orig_pos) + (data_size & 1), SEEK_CUR);

    }

    avio_seek(pb, iff->body_pos, SEEK_SET);

    switch(st->codec->codec_type) {

    case AVMEDIA_TYPE_AUDIO:

        av_set_pts_info(st, 32, 1, st->codec->sample_rate);

        switch(compression) {

        case COMP_NONE:

            st->codec->codec_id = CODEC_ID_PCM_S8;

            break;

        case COMP_FIB:

            st->codec->codec_id = CODEC_ID_8SVX_FIB;

            break;

        case COMP_EXP:

            st->codec->codec_id = CODEC_ID_8SVX_EXP;

            break;

        default:

            av_log(s, AV_LOG_ERROR, "unknown compression method\n");

            return -1;

        }

        st->codec->bits_per_coded_sample = 8;

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

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

        break;

    case AVMEDIA_TYPE_VIDEO:

        switch (compression) {

        case BITMAP_RAW:

            st->codec->codec_id = CODEC_ID_IFF_ILBM;

            break;

        case BITMAP_BYTERUN1:

            st->codec->codec_id = CODEC_ID_IFF_BYTERUN1;

            break;

        default:

            av_log(s, AV_LOG_ERROR, "unknown compression method\n");

            return AVERROR_INVALIDDATA;

        }

        break;

    default:

        return -1;

    }

    return 0;

}

static int iff_read_packet(AVFormatContext *s,

                           AVPacket *pkt)

{

    IffDemuxContext *iff = s->priv_data;

    AVIOContext *pb = s->pb;

    AVStream *st = s->streams[0];

    int ret;

    if(iff->sent_bytes >= iff->body_size)

        return AVERROR(EIO);

    if(st->codec->channels == 2) {

        uint8_t sample_buffer[PACKET_SIZE];

        ret = avio_read(pb, sample_buffer, PACKET_SIZE);

        if(av_new_packet(pkt, PACKET_SIZE) < 0) {

            av_log(s, AV_LOG_ERROR, "cannot allocate packet\n");

            return AVERROR(ENOMEM);

        }

        interleave_stereo(sample_buffer, pkt->data, PACKET_SIZE);

    } else if (st->codec->codec_type == AVMEDIA_TYPE_VIDEO) {

        ret = av_get_packet(pb, pkt, iff->body_size);

    } else {

        ret = av_get_packet(pb, pkt, PACKET_SIZE);

    }

    if(iff->sent_bytes == 0)

        pkt->flags |= AV_PKT_FLAG_KEY;

    if(st->codec->codec_type == AVMEDIA_TYPE_AUDIO) {

        iff->sent_bytes += PACKET_SIZE;

    } else {

        iff->sent_bytes = iff->body_size;

    }

    pkt->stream_index = 0;

    if(st->codec->codec_type == AVMEDIA_TYPE_AUDIO) {

        pkt->pts = iff->audio_frame_count;

        iff->audio_frame_count += ret / st->codec->channels;

    }

    return ret;

}

AVInputFormat ff_iff_demuxer = {

    "IFF",

    NULL_IF_CONFIG_SMALL("IFF format"),

    sizeof(IffDemuxContext),

    iff_probe,

    iff_read_header,

    iff_read_packet,

};