PeerStreamer

/*

 * FFM (ffserver live feed) muxer

 * Copyright (c) 2001 Fabrice Bellard

 *

 * 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 "libavutil/intreadwrite.h"

#include "avformat.h"

#include "ffm.h"

static void flush_packet(AVFormatContext *s)

{

    FFMContext *ffm = s->priv_data;

    int fill_size, h;

    ByteIOContext *pb = s->pb;

    fill_size = ffm->packet_end - ffm->packet_ptr;

    memset(ffm->packet_ptr, 0, fill_size);

    if (url_ftell(pb) % ffm->packet_size)

        av_abort();

    /* put header */

    put_be16(pb, PACKET_ID);

    put_be16(pb, fill_size);

    put_be64(pb, ffm->dts);

    h = ffm->frame_offset;

    if (ffm->first_packet)

        h |= 0x8000;

    put_be16(pb, h);

    put_buffer(pb, ffm->packet, ffm->packet_end - ffm->packet);

    put_flush_packet(pb);

    /* prepare next packet */

    ffm->frame_offset = 0; /* no key frame */

    ffm->packet_ptr = ffm->packet;

    ffm->first_packet = 0;

}

/* 'first' is true if first data of a frame */

static void ffm_write_data(AVFormatContext *s,

                           const uint8_t *buf, int size,

                           int64_t dts, int header)

{

    FFMContext *ffm = s->priv_data;

    int len;

    if (header && ffm->frame_offset == 0) {

        ffm->frame_offset = ffm->packet_ptr - ffm->packet + FFM_HEADER_SIZE;

        ffm->dts = dts;

    }

    /* write as many packets as needed */

    while (size > 0) {

        len = ffm->packet_end - ffm->packet_ptr;

        if (len > size)

            len = size;

        memcpy(ffm->packet_ptr, buf, len);

        ffm->packet_ptr += len;

        buf += len;

        size -= len;

        if (ffm->packet_ptr >= ffm->packet_end)

            flush_packet(s);

    }

}

static int ffm_write_header(AVFormatContext *s)

{

    FFMContext *ffm = s->priv_data;

    AVStream *st;

    ByteIOContext *pb = s->pb;

    AVCodecContext *codec;

    int bit_rate, i;

    ffm->packet_size = FFM_PACKET_SIZE;

    /* header */

    put_le32(pb, MKTAG('F', 'F', 'M', '1'));

    put_be32(pb, ffm->packet_size);

    put_be64(pb, 0); /* current write position */

    put_be32(pb, s->nb_streams);

    bit_rate = 0;

    for(i=0;i<s->nb_streams;i++) {

        st = s->streams[i];

        bit_rate += st->codec->bit_rate;

    }

    put_be32(pb, bit_rate);

    /* list of streams */

    for(i=0;i<s->nb_streams;i++) {

        st = s->streams[i];

        av_set_pts_info(st, 64, 1, 1000000);

        codec = st->codec;

        /* generic info */

        put_be32(pb, codec->codec_id);

        put_byte(pb, codec->codec_type);

        put_be32(pb, codec->bit_rate);

        put_be32(pb, st->quality);

        put_be32(pb, codec->flags);

        put_be32(pb, codec->flags2);

        put_be32(pb, codec->debug);

        /* specific info */

        switch(codec->codec_type) {

        case AVMEDIA_TYPE_VIDEO:

            put_be32(pb, codec->time_base.num);

            put_be32(pb, codec->time_base.den);

            put_be16(pb, codec->width);

            put_be16(pb, codec->height);

            put_be16(pb, codec->gop_size);

            put_be32(pb, codec->pix_fmt);

            put_byte(pb, codec->qmin);

            put_byte(pb, codec->qmax);

            put_byte(pb, codec->max_qdiff);

            put_be16(pb, (int) (codec->qcompress * 10000.0));

            put_be16(pb, (int) (codec->qblur * 10000.0));

            put_be32(pb, codec->bit_rate_tolerance);

            put_strz(pb, codec->rc_eq ? codec->rc_eq : "tex^qComp");

            put_be32(pb, codec->rc_max_rate);

            put_be32(pb, codec->rc_min_rate);

            put_be32(pb, codec->rc_buffer_size);

            put_be64(pb, av_dbl2int(codec->i_quant_factor));

            put_be64(pb, av_dbl2int(codec->b_quant_factor));

            put_be64(pb, av_dbl2int(codec->i_quant_offset));

            put_be64(pb, av_dbl2int(codec->b_quant_offset));

            put_be32(pb, codec->dct_algo);

            put_be32(pb, codec->strict_std_compliance);

            put_be32(pb, codec->max_b_frames);

            put_be32(pb, codec->luma_elim_threshold);

            put_be32(pb, codec->chroma_elim_threshold);

            put_be32(pb, codec->mpeg_quant);

            put_be32(pb, codec->intra_dc_precision);

            put_be32(pb, codec->me_method);

            put_be32(pb, codec->mb_decision);

            put_be32(pb, codec->nsse_weight);

            put_be32(pb, codec->frame_skip_cmp);

            put_be64(pb, av_dbl2int(codec->rc_buffer_aggressivity));

            put_be32(pb, codec->codec_tag);

            put_byte(pb, codec->thread_count);

            put_be32(pb, codec->coder_type);

            put_be32(pb, codec->me_cmp);

            put_be32(pb, codec->partitions);

            put_be32(pb, codec->me_subpel_quality);

            put_be32(pb, codec->me_range);

            put_be32(pb, codec->keyint_min);

            put_be32(pb, codec->scenechange_threshold);

            put_be32(pb, codec->b_frame_strategy);

            put_be64(pb, av_dbl2int(codec->qcompress));

            put_be64(pb, av_dbl2int(codec->qblur));

            put_be32(pb, codec->max_qdiff);

            put_be32(pb, codec->refs);

            put_be32(pb, codec->directpred);

            break;

        case AVMEDIA_TYPE_AUDIO:

            put_be32(pb, codec->sample_rate);

            put_le16(pb, codec->channels);

            put_le16(pb, codec->frame_size);

            put_le16(pb, codec->sample_fmt);

            break;

        default:

            return -1;

        }

        if (codec->flags & CODEC_FLAG_GLOBAL_HEADER) {

            put_be32(pb, codec->extradata_size);

            put_buffer(pb, codec->extradata, codec->extradata_size);

        }

    }

    /* flush until end of block reached */

    while ((url_ftell(pb) % ffm->packet_size) != 0)

        put_byte(pb, 0);

    put_flush_packet(pb);

    /* init packet mux */

    ffm->packet_ptr = ffm->packet;

    ffm->packet_end = ffm->packet + ffm->packet_size - FFM_HEADER_SIZE;

    assert(ffm->packet_end >= ffm->packet);

    ffm->frame_offset = 0;

    ffm->dts = 0;

    ffm->first_packet = 1;

    return 0;

}

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

{

    int64_t dts;

    uint8_t header[FRAME_HEADER_SIZE+4];

    int header_size = FRAME_HEADER_SIZE;

    dts = s->timestamp + pkt->dts;

    /* packet size & key_frame */

    header[0] = pkt->stream_index;

    header[1] = 0;

    if (pkt->flags & PKT_FLAG_KEY)

        header[1] |= FLAG_KEY_FRAME;

    AV_WB24(header+2, pkt->size);

    AV_WB24(header+5, pkt->duration);

    AV_WB64(header+8, s->timestamp + pkt->pts);

    if (pkt->pts != pkt->dts) {

        header[1] |= FLAG_DTS;

        AV_WB32(header+16, pkt->pts - pkt->dts);

        header_size += 4;

    }

    ffm_write_data(s, header, header_size, dts, 1);

    ffm_write_data(s, pkt->data, pkt->size, dts, 0);

    return 0;

}

static int ffm_write_trailer(AVFormatContext *s)

{

    ByteIOContext *pb = s->pb;

    FFMContext *ffm = s->priv_data;

    /* flush packets */

    if (ffm->packet_ptr > ffm->packet)

        flush_packet(s);

    put_flush_packet(pb);

    return 0;

}

AVOutputFormat ffm_muxer = {

    "ffm",

    NULL_IF_CONFIG_SMALL("FFM (FFserver live feed) format"),

    "",

    "ffm",

    sizeof(FFMContext),

    /* not really used */

    CODEC_ID_MP2,

    CODEC_ID_MPEG1VIDEO,

    ffm_write_header,

    ffm_write_packet,

    ffm_write_trailer,

};