/* * "Real" compatible muxer. * Copyright (c) 2000, 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 "avformat.h" #include "avio_internal.h" #include "rm.h" #include "libavutil/dict.h" typedef struct StreamInfo { int nb_packets; int packet_total_size; int packet_max_size; /* codec related output */ int bit_rate; AVRational frame_rate; int nb_frames; /* current frame number */ int total_frames; /* total number of frames */ int num; AVCodecContext *enc; } StreamInfo; typedef struct RMMuxContext { StreamInfo streams[2]; StreamInfo *audio_stream, *video_stream; int data_pos; /* position of the data after the header */ } RMMuxContext; /* in ms */ #define BUFFER_DURATION 0 /* the header needs at most 7 + 4 + 12 B */ #define MAX_HEADER_SIZE (7 + 4 + 12) /* UINT16_MAX is the maximal chunk size */ #define MAX_PACKET_SIZE (UINT16_MAX - MAX_HEADER_SIZE) static void put_str(AVIOContext *s, const char *tag) { avio_wb16(s,strlen(tag)); while (*tag) { avio_w8(s, *tag++); } } static void put_str8(AVIOContext *s, const char *tag) { avio_w8(s, strlen(tag)); while (*tag) { avio_w8(s, *tag++); } } static int rv10_write_header(AVFormatContext *ctx, int data_size, int index_pos) { RMMuxContext *rm = ctx->priv_data; AVIOContext *s = ctx->pb; StreamInfo *stream; unsigned char *data_offset_ptr, *start_ptr; const char *desc, *mimetype; int nb_packets, packet_total_size, packet_max_size, size, packet_avg_size, i; int bit_rate, v, duration, flags, data_pos; AVDictionaryEntry *tag; start_ptr = s->buf_ptr; ffio_wfourcc(s, ".RMF"); avio_wb32(s,18); /* header size */ avio_wb16(s,0); avio_wb32(s,0); avio_wb32(s,4 + ctx->nb_streams); /* num headers */ ffio_wfourcc(s,"PROP"); avio_wb32(s, 50); avio_wb16(s, 0); packet_max_size = 0; packet_total_size = 0; nb_packets = 0; bit_rate = 0; duration = 0; for(i=0;i<ctx->nb_streams;i++) { StreamInfo *stream = &rm->streams[i]; bit_rate += stream->bit_rate; if (stream->packet_max_size > packet_max_size) packet_max_size = stream->packet_max_size; nb_packets += stream->nb_packets; packet_total_size += stream->packet_total_size; /* select maximum duration */ v = av_rescale_q_rnd(stream->total_frames, (AVRational){1000, 1}, stream->frame_rate, AV_ROUND_ZERO); if (v > duration) duration = v; } avio_wb32(s, bit_rate); /* max bit rate */ avio_wb32(s, bit_rate); /* avg bit rate */ avio_wb32(s, packet_max_size); /* max packet size */ if (nb_packets > 0) packet_avg_size = packet_total_size / nb_packets; else packet_avg_size = 0; avio_wb32(s, packet_avg_size); /* avg packet size */ avio_wb32(s, nb_packets); /* num packets */ avio_wb32(s, duration); /* duration */ avio_wb32(s, BUFFER_DURATION); /* preroll */ avio_wb32(s, index_pos); /* index offset */ /* computation of data the data offset */ data_offset_ptr = s->buf_ptr; avio_wb32(s, 0); /* data offset : will be patched after */ avio_wb16(s, ctx->nb_streams); /* num streams */ flags = 1 | 2; /* save allowed & perfect play */ if (!s->seekable) flags |= 4; /* live broadcast */ avio_wb16(s, flags); /* comments */ ffio_wfourcc(s,"CONT"); size = 4 * 2 + 10; for(i=0; i<FF_ARRAY_ELEMS(ff_rm_metadata); i++) { tag = av_dict_get(ctx->metadata, ff_rm_metadata[i], NULL, 0); if(tag) size += strlen(tag->value); } avio_wb32(s,size); avio_wb16(s,0); for(i=0; i<FF_ARRAY_ELEMS(ff_rm_metadata); i++) { tag = av_dict_get(ctx->metadata, ff_rm_metadata[i], NULL, 0); put_str(s, tag ? tag->value : ""); } for(i=0;i<ctx->nb_streams;i++) { int codec_data_size; stream = &rm->streams[i]; if (stream->enc->codec_type == AVMEDIA_TYPE_AUDIO) { desc = "The Audio Stream"; mimetype = "audio/x-pn-realaudio"; codec_data_size = 73; } else { desc = "The Video Stream"; mimetype = "video/x-pn-realvideo"; codec_data_size = 34; } ffio_wfourcc(s,"MDPR"); size = 10 + 9 * 4 + strlen(desc) + strlen(mimetype) + codec_data_size; avio_wb32(s, size); avio_wb16(s, 0); avio_wb16(s, i); /* stream number */ avio_wb32(s, stream->bit_rate); /* max bit rate */ avio_wb32(s, stream->bit_rate); /* avg bit rate */ avio_wb32(s, stream->packet_max_size); /* max packet size */ if (stream->nb_packets > 0) packet_avg_size = stream->packet_total_size / stream->nb_packets; else packet_avg_size = 0; avio_wb32(s, packet_avg_size); /* avg packet size */ avio_wb32(s, 0); /* start time */ avio_wb32(s, BUFFER_DURATION); /* preroll */ /* duration */ if (!s->seekable || !stream->total_frames) avio_wb32(s, (int)(3600 * 1000)); else avio_wb32(s, av_rescale_q_rnd(stream->total_frames, (AVRational){1000, 1}, stream->frame_rate, AV_ROUND_ZERO)); put_str8(s, desc); put_str8(s, mimetype); avio_wb32(s, codec_data_size); if (stream->enc->codec_type == AVMEDIA_TYPE_AUDIO) { int coded_frame_size, fscode, sample_rate; sample_rate = stream->enc->sample_rate; coded_frame_size = (stream->enc->bit_rate * stream->enc->frame_size) / (8 * sample_rate); /* audio codec info */ avio_write(s, ".ra", 3); avio_w8(s, 0xfd); avio_wb32(s, 0x00040000); /* version */ ffio_wfourcc(s, ".ra4"); avio_wb32(s, 0x01b53530); /* stream length */ avio_wb16(s, 4); /* unknown */ avio_wb32(s, 0x39); /* header size */ switch(sample_rate) { case 48000: case 24000: case 12000: fscode = 1; break; default: case 44100: case 22050: case 11025: fscode = 2; break; case 32000: case 16000: case 8000: fscode = 3; } avio_wb16(s, fscode); /* codec additional info, for AC-3, seems to be a frequency code */ /* special hack to compensate rounding errors... */ if (coded_frame_size == 557) coded_frame_size--; avio_wb32(s, coded_frame_size); /* frame length */ avio_wb32(s, 0x51540); /* unknown */ avio_wb32(s, stream->enc->bit_rate / 8 * 60); /* bytes per minute */ avio_wb32(s, stream->enc->bit_rate / 8 * 60); /* bytes per minute */ avio_wb16(s, 0x01); /* frame length : seems to be very important */ avio_wb16(s, coded_frame_size); avio_wb32(s, 0); /* unknown */ avio_wb16(s, stream->enc->sample_rate); /* sample rate */ avio_wb32(s, 0x10); /* unknown */ avio_wb16(s, stream->enc->channels); put_str8(s, "Int0"); /* codec name */ if (stream->enc->codec_tag) { avio_w8(s, 4); /* tag length */ avio_wl32(s, stream->enc->codec_tag); } else { av_log(ctx, AV_LOG_ERROR, "Invalid codec tag\n"); return -1; } avio_wb16(s, 0); /* title length */ avio_wb16(s, 0); /* author length */ avio_wb16(s, 0); /* copyright length */ avio_w8(s, 0); /* end of header */ } else { /* video codec info */ avio_wb32(s,34); /* size */ ffio_wfourcc(s, "VIDO"); if(stream->enc->codec_id == AV_CODEC_ID_RV10) ffio_wfourcc(s,"RV10"); else ffio_wfourcc(s,"RV20"); avio_wb16(s, stream->enc->width); avio_wb16(s, stream->enc->height); avio_wb16(s, stream->frame_rate.num / stream->frame_rate.den); /* frames per seconds ? */ avio_wb32(s,0); /* unknown meaning */ avio_wb16(s, stream->frame_rate.num / stream->frame_rate.den); /* unknown meaning */ avio_wb32(s,0); /* unknown meaning */ avio_wb16(s, 8); /* unknown meaning */ /* Seems to be the codec version: only use basic H263. The next versions seems to add a diffential DC coding as in MPEG... nothing new under the sun */ if(stream->enc->codec_id == AV_CODEC_ID_RV10) avio_wb32(s,0x10000000); else avio_wb32(s,0x20103001); //avio_wb32(s,0x10003000); } } /* patch data offset field */ data_pos = s->buf_ptr - start_ptr; rm->data_pos = data_pos; data_offset_ptr[0] = data_pos >> 24; data_offset_ptr[1] = data_pos >> 16; data_offset_ptr[2] = data_pos >> 8; data_offset_ptr[3] = data_pos; /* data stream */ ffio_wfourcc(s, "DATA"); avio_wb32(s,data_size + 10 + 8); avio_wb16(s,0); avio_wb32(s, nb_packets); /* number of packets */ avio_wb32(s,0); /* next data header */ return 0; } static void write_packet_header(AVFormatContext *ctx, StreamInfo *stream, int length, int key_frame) { int timestamp; AVIOContext *s = ctx->pb; stream->nb_packets++; stream->packet_total_size += length; if (length > stream->packet_max_size) stream->packet_max_size = length; avio_wb16(s,0); /* version */ avio_wb16(s,length + 12); avio_wb16(s, stream->num); /* stream number */ timestamp = av_rescale_q_rnd(stream->nb_frames, (AVRational){1000, 1}, stream->frame_rate, AV_ROUND_ZERO); avio_wb32(s, timestamp); /* timestamp */ avio_w8(s, 0); /* reserved */ avio_w8(s, key_frame ? 2 : 0); /* flags */ } static int rm_write_header(AVFormatContext *s) { RMMuxContext *rm = s->priv_data; StreamInfo *stream; int n; AVCodecContext *codec; if (s->nb_streams > 2) { av_log(s, AV_LOG_ERROR, "At most 2 streams are currently supported for muxing in RM\n"); return AVERROR_PATCHWELCOME; } for(n=0;n<s->nb_streams;n++) { AVStream *st = s->streams[n]; s->streams[n]->id = n; codec = s->streams[n]->codec; stream = &rm->streams[n]; memset(stream, 0, sizeof(StreamInfo)); stream->num = n; stream->bit_rate = codec->bit_rate; stream->enc = codec; switch(codec->codec_type) { case AVMEDIA_TYPE_AUDIO: rm->audio_stream = stream; stream->frame_rate = (AVRational){codec->sample_rate, codec->frame_size}; /* XXX: dummy values */ stream->packet_max_size = 1024; stream->nb_packets = 0; stream->total_frames = stream->nb_packets; break; case AVMEDIA_TYPE_VIDEO: rm->video_stream = stream; // TODO: should be avg_frame_rate stream->frame_rate = av_inv_q(st->time_base); /* XXX: dummy values */ stream->packet_max_size = 4096; stream->nb_packets = 0; stream->total_frames = stream->nb_packets; break; default: return -1; } } if (rv10_write_header(s, 0, 0)) return AVERROR_INVALIDDATA; avio_flush(s->pb); return 0; } static int rm_write_audio(AVFormatContext *s, const uint8_t *buf, int size, int flags) { RMMuxContext *rm = s->priv_data; AVIOContext *pb = s->pb; StreamInfo *stream = rm->audio_stream; int i; write_packet_header(s, stream, size, !!(flags & AV_PKT_FLAG_KEY)); if (stream->enc->codec_id == AV_CODEC_ID_AC3) { /* for AC-3, the words seem to be reversed */ for (i = 0; i < size; i += 2) { avio_w8(pb, buf[i + 1]); avio_w8(pb, buf[i]); } } else { avio_write(pb, buf, size); } stream->nb_frames++; return 0; } static int rm_write_video(AVFormatContext *s, const uint8_t *buf, int size, int flags) { RMMuxContext *rm = s->priv_data; AVIOContext *pb = s->pb; StreamInfo *stream = rm->video_stream; int key_frame = !!(flags & AV_PKT_FLAG_KEY); /* XXX: this is incorrect: should be a parameter */ /* Well, I spent some time finding the meaning of these bits. I am not sure I understood everything, but it works !! */ #if 1 if (size > MAX_PACKET_SIZE) { av_log(s, AV_LOG_ERROR, "Muxing packets larger than 64 kB (%d) is not supported\n", size); return AVERROR_PATCHWELCOME; } write_packet_header(s, stream, size + 7 + (size >= 0x4000)*4, key_frame); /* bit 7: '1' if final packet of a frame converted in several packets */ avio_w8(pb, 0x81); /* bit 7: '1' if I frame. bits 6..0 : sequence number in current frame starting from 1 */ if (key_frame) { avio_w8(pb, 0x81); } else { avio_w8(pb, 0x01); } if(size >= 0x4000){ avio_wb32(pb, size); /* total frame size */ avio_wb32(pb, size); /* offset from the start or the end */ }else{ avio_wb16(pb, 0x4000 | size); /* total frame size */ avio_wb16(pb, 0x4000 | size); /* offset from the start or the end */ } #else /* full frame */ write_packet_header(s, size + 6); avio_w8(pb, 0xc0); avio_wb16(pb, 0x4000 + size); /* total frame size */ avio_wb16(pb, 0x4000 + packet_number * 126); /* position in stream */ #endif avio_w8(pb, stream->nb_frames & 0xff); avio_write(pb, buf, size); stream->nb_frames++; return 0; } static int rm_write_packet(AVFormatContext *s, AVPacket *pkt) { if (s->streams[pkt->stream_index]->codec->codec_type == AVMEDIA_TYPE_AUDIO) return rm_write_audio(s, pkt->data, pkt->size, pkt->flags); else return rm_write_video(s, pkt->data, pkt->size, pkt->flags); } static int rm_write_trailer(AVFormatContext *s) { RMMuxContext *rm = s->priv_data; int data_size, index_pos, i; AVIOContext *pb = s->pb; if (s->pb->seekable) { /* end of file: finish to write header */ index_pos = avio_tell(pb); data_size = index_pos - rm->data_pos; /* FIXME: write index */ /* undocumented end header */ avio_wb32(pb, 0); avio_wb32(pb, 0); avio_seek(pb, 0, SEEK_SET); for(i=0;i<s->nb_streams;i++) rm->streams[i].total_frames = rm->streams[i].nb_frames; rv10_write_header(s, data_size, 0); } else { /* undocumented end header */ avio_wb32(pb, 0); avio_wb32(pb, 0); } return 0; } AVOutputFormat ff_rm_muxer = { .name = "rm", .long_name = NULL_IF_CONFIG_SMALL("RealMedia"), .mime_type = "application/vnd.rn-realmedia", .extensions = "rm,ra", .priv_data_size = sizeof(RMMuxContext), .audio_codec = AV_CODEC_ID_AC3, .video_codec = AV_CODEC_ID_RV10, .write_header = rm_write_header, .write_packet = rm_write_packet, .write_trailer = rm_write_trailer, .codec_tag = (const AVCodecTag* const []){ ff_rm_codec_tags, 0 }, };