FFmpeg: libavformat/ffmenc.c Source File

00001 /*
00002  * FFM (ffserver live feed) muxer
00003  * Copyright (c) 2001 Fabrice Bellard
00004  *
00005  * This file is part of FFmpeg.
00006  *
00007  * FFmpeg is free software; you can redistribute it and/or
00008  * modify it under the terms of the GNU Lesser General Public
00009  * License as published by the Free Software Foundation; either
00010  * version 2.1 of the License, or (at your option) any later version.
00011  *
00012  * FFmpeg is distributed in the hope that it will be useful,
00013  * but WITHOUT ANY WARRANTY; without even the implied warranty of
00014  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
00015  * Lesser General Public License for more details.
00016  *
00017  * You should have received a copy of the GNU Lesser General Public
00018  * License along with FFmpeg; if not, write to the Free Software
00019  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
00020  */
00021 
00022 #include "libavutil/intreadwrite.h"
00023 #include "avformat.h"
00024 #include "ffm.h"
00025 
00026 static void flush_packet(AVFormatContext *s)
00027 {
00028     FFMContext *ffm = s->priv_data;
00029     int fill_size, h;
00030     ByteIOContext *pb = s->pb;
00031 
00032     fill_size = ffm->packet_end - ffm->packet_ptr;
00033     memset(ffm->packet_ptr, 0, fill_size);
00034 
00035     if (url_ftell(pb) % ffm->packet_size)
00036         av_abort();
00037 
00038     /* put header */
00039     put_be16(pb, PACKET_ID);
00040     put_be16(pb, fill_size);
00041     put_be64(pb, ffm->dts);
00042     h = ffm->frame_offset;
00043     if (ffm->first_packet)
00044         h |= 0x8000;
00045     put_be16(pb, h);
00046     put_buffer(pb, ffm->packet, ffm->packet_end - ffm->packet);
00047     put_flush_packet(pb);
00048 
00049     /* prepare next packet */
00050     ffm->frame_offset = 0; /* no key frame */
00051     ffm->packet_ptr = ffm->packet;
00052     ffm->first_packet = 0;
00053 }
00054 
00055 /* 'first' is true if first data of a frame */
00056 static void ffm_write_data(AVFormatContext *s,
00057                            const uint8_t *buf, int size,
00058                            int64_t dts, int header)
00059 {
00060     FFMContext *ffm = s->priv_data;
00061     int len;
00062 
00063     if (header && ffm->frame_offset == 0) {
00064         ffm->frame_offset = ffm->packet_ptr - ffm->packet + FFM_HEADER_SIZE;
00065         ffm->dts = dts;
00066     }
00067 
00068     /* write as many packets as needed */
00069     while (size > 0) {
00070         len = ffm->packet_end - ffm->packet_ptr;
00071         if (len > size)
00072             len = size;
00073         memcpy(ffm->packet_ptr, buf, len);
00074 
00075         ffm->packet_ptr += len;
00076         buf += len;
00077         size -= len;
00078         if (ffm->packet_ptr >= ffm->packet_end)
00079             flush_packet(s);
00080     }
00081 }
00082 
00083 static int ffm_write_header(AVFormatContext *s)
00084 {
00085     FFMContext *ffm = s->priv_data;
00086     AVStream *st;
00087     ByteIOContext *pb = s->pb;
00088     AVCodecContext *codec;
00089     int bit_rate, i;
00090 
00091     ffm->packet_size = FFM_PACKET_SIZE;
00092 
00093     /* header */
00094     put_le32(pb, MKTAG('F', 'F', 'M', '1'));
00095     put_be32(pb, ffm->packet_size);
00096     put_be64(pb, 0); /* current write position */
00097 
00098     put_be32(pb, s->nb_streams);
00099     bit_rate = 0;
00100     for(i=0;i<s->nb_streams;i++) {
00101         st = s->streams[i];
00102         bit_rate += st->codec->bit_rate;
00103     }
00104     put_be32(pb, bit_rate);
00105 
00106     /* list of streams */
00107     for(i=0;i<s->nb_streams;i++) {
00108         st = s->streams[i];
00109         av_set_pts_info(st, 64, 1, 1000000);
00110 
00111         codec = st->codec;
00112         /* generic info */
00113         put_be32(pb, codec->codec_id);
00114         put_byte(pb, codec->codec_type);
00115         put_be32(pb, codec->bit_rate);
00116         put_be32(pb, st->quality);
00117         put_be32(pb, codec->flags);
00118         put_be32(pb, codec->flags2);
00119         put_be32(pb, codec->debug);
00120         /* specific info */
00121         switch(codec->codec_type) {
00122         case AVMEDIA_TYPE_VIDEO:
00123             put_be32(pb, codec->time_base.num);
00124             put_be32(pb, codec->time_base.den);
00125             put_be16(pb, codec->width);
00126             put_be16(pb, codec->height);
00127             put_be16(pb, codec->gop_size);
00128             put_be32(pb, codec->pix_fmt);
00129             put_byte(pb, codec->qmin);
00130             put_byte(pb, codec->qmax);
00131             put_byte(pb, codec->max_qdiff);
00132             put_be16(pb, (int) (codec->qcompress * 10000.0));
00133             put_be16(pb, (int) (codec->qblur * 10000.0));
00134             put_be32(pb, codec->bit_rate_tolerance);
00135             put_strz(pb, codec->rc_eq ? codec->rc_eq : "tex^qComp");
00136             put_be32(pb, codec->rc_max_rate);
00137             put_be32(pb, codec->rc_min_rate);
00138             put_be32(pb, codec->rc_buffer_size);
00139             put_be64(pb, av_dbl2int(codec->i_quant_factor));
00140             put_be64(pb, av_dbl2int(codec->b_quant_factor));
00141             put_be64(pb, av_dbl2int(codec->i_quant_offset));
00142             put_be64(pb, av_dbl2int(codec->b_quant_offset));
00143             put_be32(pb, codec->dct_algo);
00144             put_be32(pb, codec->strict_std_compliance);
00145             put_be32(pb, codec->max_b_frames);
00146             put_be32(pb, codec->luma_elim_threshold);
00147             put_be32(pb, codec->chroma_elim_threshold);
00148             put_be32(pb, codec->mpeg_quant);
00149             put_be32(pb, codec->intra_dc_precision);
00150             put_be32(pb, codec->me_method);
00151             put_be32(pb, codec->mb_decision);
00152             put_be32(pb, codec->nsse_weight);
00153             put_be32(pb, codec->frame_skip_cmp);
00154             put_be64(pb, av_dbl2int(codec->rc_buffer_aggressivity));
00155             put_be32(pb, codec->codec_tag);
00156             put_byte(pb, codec->thread_count);
00157             put_be32(pb, codec->coder_type);
00158             put_be32(pb, codec->me_cmp);
00159             put_be32(pb, codec->partitions);
00160             put_be32(pb, codec->me_subpel_quality);
00161             put_be32(pb, codec->me_range);
00162             put_be32(pb, codec->keyint_min);
00163             put_be32(pb, codec->scenechange_threshold);
00164             put_be32(pb, codec->b_frame_strategy);
00165             put_be64(pb, av_dbl2int(codec->qcompress));
00166             put_be64(pb, av_dbl2int(codec->qblur));
00167             put_be32(pb, codec->max_qdiff);
00168             put_be32(pb, codec->refs);
00169             put_be32(pb, codec->directpred);
00170             break;
00171         case AVMEDIA_TYPE_AUDIO:
00172             put_be32(pb, codec->sample_rate);
00173             put_le16(pb, codec->channels);
00174             put_le16(pb, codec->frame_size);
00175             put_le16(pb, codec->sample_fmt);
00176             break;
00177         default:
00178             return -1;
00179         }
00180         if (codec->flags & CODEC_FLAG_GLOBAL_HEADER) {
00181             put_be32(pb, codec->extradata_size);
00182             put_buffer(pb, codec->extradata, codec->extradata_size);
00183         }
00184     }
00185 
00186     /* flush until end of block reached */
00187     while ((url_ftell(pb) % ffm->packet_size) != 0)
00188         put_byte(pb, 0);
00189 
00190     put_flush_packet(pb);
00191 
00192     /* init packet mux */
00193     ffm->packet_ptr = ffm->packet;
00194     ffm->packet_end = ffm->packet + ffm->packet_size - FFM_HEADER_SIZE;
00195     assert(ffm->packet_end >= ffm->packet);
00196     ffm->frame_offset = 0;
00197     ffm->dts = 0;
00198     ffm->first_packet = 1;
00199 
00200     return 0;
00201 }
00202 
00203 static int ffm_write_packet(AVFormatContext *s, AVPacket *pkt)
00204 {
00205     int64_t dts;
00206     uint8_t header[FRAME_HEADER_SIZE+4];
00207     int header_size = FRAME_HEADER_SIZE;
00208 
00209     dts = s->timestamp + pkt->dts;
00210     /* packet size & key_frame */
00211     header[0] = pkt->stream_index;
00212     header[1] = 0;
00213     if (pkt->flags & AV_PKT_FLAG_KEY)
00214         header[1] |= FLAG_KEY_FRAME;
00215     AV_WB24(header+2, pkt->size);
00216     AV_WB24(header+5, pkt->duration);
00217     AV_WB64(header+8, s->timestamp + pkt->pts);
00218     if (pkt->pts != pkt->dts) {
00219         header[1] |= FLAG_DTS;
00220         AV_WB32(header+16, pkt->pts - pkt->dts);
00221         header_size += 4;
00222     }
00223     ffm_write_data(s, header, header_size, dts, 1);
00224     ffm_write_data(s, pkt->data, pkt->size, dts, 0);
00225 
00226     return 0;
00227 }
00228 
00229 static int ffm_write_trailer(AVFormatContext *s)
00230 {
00231     ByteIOContext *pb = s->pb;
00232     FFMContext *ffm = s->priv_data;
00233 
00234     /* flush packets */
00235     if (ffm->packet_ptr > ffm->packet)
00236         flush_packet(s);
00237 
00238     put_flush_packet(pb);
00239 
00240     return 0;
00241 }
00242 
00243 AVOutputFormat ffm_muxer = {
00244     "ffm",
00245     NULL_IF_CONFIG_SMALL("FFM (FFserver live feed) format"),
00246     "",
00247     "ffm",
00248     sizeof(FFMContext),
00249     /* not really used */
00250     CODEC_ID_MP2,
00251     CODEC_ID_MPEG1VIDEO,
00252     ffm_write_header,
00253     ffm_write_packet,
00254     ffm_write_trailer,
00255 };