libavformat/ffmenc.c

   1 /*
   2  * FFM (ffserver live feed) muxer
   3  * Copyright (c) 2001 Fabrice Bellard
   4  *
   5  * This file is part of FFmpeg.
   6  *
   7  * FFmpeg is free software; you can redistribute it and/or
   8  * modify it under the terms of the GNU Lesser General Public
   9  * License as published by the Free Software Foundation; either
  10  * version 2.1 of the License, or (at your option) any later version.
  11  *
  12  * FFmpeg is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  15  * Lesser General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU Lesser General Public
  18  * License along with FFmpeg; if not, write to the Free Software
  19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  20  */
  21
  22 #include "libavutil/intreadwrite.h"
  23 #include "avformat.h"
  24 #include "ffm.h"
  25
  26 static void flush_packet(AVFormatContext *s)
  27 {
  28     FFMContext *ffm = s->priv_data;
  29     int fill_size, h;
  30     ByteIOContext *pb = s->pb;
  31
  32     fill_size = ffm->packet_end - ffm->packet_ptr;
  33     memset(ffm->packet_ptr, 0, fill_size);
  34
  35     if (url_ftell(pb) % ffm->packet_size)
  36         av_abort();
  37
  38     /* put header */
  39     put_be16(pb, PACKET_ID);
  40     put_be16(pb, fill_size);
  41     put_be64(pb, ffm->dts);
  42     h = ffm->frame_offset;
  43     if (ffm->first_packet)
  44         h |= 0x8000;
  45     put_be16(pb, h);
  46     put_buffer(pb, ffm->packet, ffm->packet_end - ffm->packet);
  47     put_flush_packet(pb);
  48
  49     /* prepare next packet */
  50     ffm->frame_offset = 0; /* no key frame */
  51     ffm->packet_ptr = ffm->packet;
  52     ffm->first_packet = 0;
  53 }
  54
  55 /* 'first' is true if first data of a frame */
  56 static void ffm_write_data(AVFormatContext *s,
  57                            const uint8_t *buf, int size,
  58                            int64_t dts, int header)
  59 {
  60     FFMContext *ffm = s->priv_data;
  61     int len;
  62
  63     if (header && ffm->frame_offset == 0) {
  64         ffm->frame_offset = ffm->packet_ptr - ffm->packet + FFM_HEADER_SIZE;
  65         ffm->dts = dts;
  66     }
  67
  68     /* write as many packets as needed */
  69     while (size > 0) {
  70         len = ffm->packet_end - ffm->packet_ptr;
  71         if (len > size)
  72             len = size;
  73         memcpy(ffm->packet_ptr, buf, len);
  74
  75         ffm->packet_ptr += len;
  76         buf += len;
  77         size -= len;
  78         if (ffm->packet_ptr >= ffm->packet_end)
  79             flush_packet(s);
  80     }
  81 }
  82
  83 static int ffm_write_header(AVFormatContext *s)
  84 {
  85     FFMContext *ffm = s->priv_data;
  86     AVStream *st;
  87     ByteIOContext *pb = s->pb;
  88     AVCodecContext *codec;
  89     int bit_rate, i;
  90
  91     ffm->packet_size = FFM_PACKET_SIZE;
  92
  93     /* header */
  94     put_le32(pb, MKTAG('F', 'F', 'M', '1'));
  95     put_be32(pb, ffm->packet_size);
  96     /* XXX: store write position in other file ? */
  97     put_be64(pb, ffm->packet_size); /* current write position */
  98
  99     put_be32(pb, s->nb_streams);
 100     bit_rate = 0;
 101     for(i=0;i<s->nb_streams;i++) {
 102         st = s->streams[i];
 103         bit_rate += st->codec->bit_rate;
 104     }
 105     put_be32(pb, bit_rate);
 106
 107     /* list of streams */
 108     for(i=0;i<s->nb_streams;i++) {
 109         st = s->streams[i];
 110         av_set_pts_info(st, 64, 1, 1000000);
 111
 112         codec = st->codec;
 113         /* generic info */
 114         put_be32(pb, codec->codec_id);
 115         put_byte(pb, codec->codec_type);
 116         put_be32(pb, codec->bit_rate);
 117         put_be32(pb, st->quality);
 118         put_be32(pb, codec->flags);
 119         put_be32(pb, codec->flags2);
 120         put_be32(pb, codec->debug);
 121         /* specific info */
 122         switch(codec->codec_type) {
 123         case CODEC_TYPE_VIDEO:
 124             put_be32(pb, codec->time_base.num);
 125             put_be32(pb, codec->time_base.den);
 126             put_be16(pb, codec->width);
 127             put_be16(pb, codec->height);
 128             put_be16(pb, codec->gop_size);
 129             put_be32(pb, codec->pix_fmt);
 130             put_byte(pb, codec->qmin);
 131             put_byte(pb, codec->qmax);
 132             put_byte(pb, codec->max_qdiff);
 133             put_be16(pb, (int) (codec->qcompress * 10000.0));
 134             put_be16(pb, (int) (codec->qblur * 10000.0));
 135             put_be32(pb, codec->bit_rate_tolerance);
 136             put_strz(pb, codec->rc_eq ? codec->rc_eq : "tex^qComp");
 137             put_be32(pb, codec->rc_max_rate);
 138             put_be32(pb, codec->rc_min_rate);
 139             put_be32(pb, codec->rc_buffer_size);
 140             put_be64(pb, av_dbl2int(codec->i_quant_factor));
 141             put_be64(pb, av_dbl2int(codec->b_quant_factor));
 142             put_be64(pb, av_dbl2int(codec->i_quant_offset));
 143             put_be64(pb, av_dbl2int(codec->b_quant_offset));
 144             put_be32(pb, codec->dct_algo);
 145             put_be32(pb, codec->strict_std_compliance);
 146             put_be32(pb, codec->max_b_frames);
 147             put_be32(pb, codec->luma_elim_threshold);
 148             put_be32(pb, codec->chroma_elim_threshold);
 149             put_be32(pb, codec->mpeg_quant);
 150             put_be32(pb, codec->intra_dc_precision);
 151             put_be32(pb, codec->me_method);
 152             put_be32(pb, codec->mb_decision);
 153             put_be32(pb, codec->nsse_weight);
 154             put_be32(pb, codec->frame_skip_cmp);
 155             put_be64(pb, av_dbl2int(codec->rc_buffer_aggressivity));
 156             put_be32(pb, codec->codec_tag);
 157             put_byte(pb, codec->thread_count);
 158             break;
 159         case CODEC_TYPE_AUDIO:
 160             put_be32(pb, codec->sample_rate);
 161             put_le16(pb, codec->channels);
 162             put_le16(pb, codec->frame_size);
 163             break;
 164         default:
 165             return -1;
 166         }
 167         if (codec->flags & CODEC_FLAG_GLOBAL_HEADER) {
 168             put_be32(pb, codec->extradata_size);
 169             put_buffer(pb, codec->extradata, codec->extradata_size);
 170         }
 171     }
 172
 173     /* flush until end of block reached */
 174     while ((url_ftell(pb) % ffm->packet_size) != 0)
 175         put_byte(pb, 0);
 176
 177     put_flush_packet(pb);
 178
 179     /* init packet mux */
 180     ffm->packet_ptr = ffm->packet;
 181     ffm->packet_end = ffm->packet + ffm->packet_size - FFM_HEADER_SIZE;
 182     assert(ffm->packet_end >= ffm->packet);
 183     ffm->frame_offset = 0;
 184     ffm->dts = 0;
 185     ffm->first_packet = 1;
 186
 187     return 0;
 188 }
 189
 190 static int ffm_write_packet(AVFormatContext *s, AVPacket *pkt)
 191 {
 192     int64_t dts;
 193     uint8_t header[FRAME_HEADER_SIZE+4];
 194     int header_size = FRAME_HEADER_SIZE;
 195
 196     dts = s->timestamp + pkt->dts;
 197     /* packet size & key_frame */
 198     header[0] = pkt->stream_index;
 199     header[1] = 0;
 200     if (pkt->flags & PKT_FLAG_KEY)
 201         header[1] |= FLAG_KEY_FRAME;
 202     AV_WB24(header+2, pkt->size);
 203     AV_WB24(header+5, pkt->duration);
 204     AV_WB64(header+8, s->timestamp + pkt->pts);
 205     if (pkt->pts != pkt->dts) {
 206         header[1] |= FLAG_DTS;
 207         AV_WB32(header+16, pkt->pts - pkt->dts);
 208         header_size += 4;
 209     }
 210     ffm_write_data(s, header, header_size, dts, 1);
 211     ffm_write_data(s, pkt->data, pkt->size, dts, 0);
 212
 213     return 0;
 214 }
 215
 216 static int ffm_write_trailer(AVFormatContext *s)
 217 {
 218     ByteIOContext *pb = s->pb;
 219     FFMContext *ffm = s->priv_data;
 220
 221     /* flush packets */
 222     if (ffm->packet_ptr > ffm->packet)
 223         flush_packet(s);
 224
 225     put_flush_packet(pb);
 226
 227     if (!url_is_streamed(pb)) {
 228         int64_t size;
 229         /* update the write offset */
 230         size = url_ftell(pb);
 231         url_fseek(pb, 8, SEEK_SET);
 232         put_be64(pb, size);
 233         put_flush_packet(pb);
 234     }
 235
 236     return 0;
 237 }
 238
 239 AVOutputFormat ffm_muxer = {
 240     "ffm",
 241     NULL_IF_CONFIG_SMALL("FFM (FFserver live feed) format"),
 242     "",
 243     "ffm",
 244     sizeof(FFMContext),
 245     /* not really used */
 246     CODEC_ID_MP2,
 247     CODEC_ID_MPEG1VIDEO,
 248     ffm_write_header,
 249     ffm_write_packet,
 250     ffm_write_trailer,
 251 };