2 * "Real" compatible muxer.
3 * Copyright (c) 2000, 2001 Fabrice Bellard
5 * This file is part of FFmpeg.
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.
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.
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
22 #include "avio_internal.h"
25 #include "libavutil/dict.h"
27 typedef struct StreamInfo {
29 int packet_total_size;
31 /* codec related output */
33 AVRational frame_rate;
34 int nb_frames; /* current frame number */
35 int total_frames; /* total number of frames */
37 AVCodecParameters *par;
40 typedef struct RMMuxContext {
41 StreamInfo streams[2];
42 StreamInfo *audio_stream, *video_stream;
43 int data_pos; /* position of the data after the header */
47 #define BUFFER_DURATION 0
48 /* the header needs at most 7 + 4 + 12 B */
49 #define MAX_HEADER_SIZE (7 + 4 + 12)
50 /* UINT16_MAX is the maximal chunk size */
51 #define MAX_PACKET_SIZE (UINT16_MAX - MAX_HEADER_SIZE)
54 static void put_str(AVIOContext *s, const char *tag)
56 avio_wb16(s,strlen(tag));
62 static void put_str8(AVIOContext *s, const char *tag)
64 avio_w8(s, strlen(tag));
70 static int rv10_write_header(AVFormatContext *ctx,
71 int data_size, int index_pos)
73 RMMuxContext *rm = ctx->priv_data;
74 AVIOContext *s = ctx->pb;
76 const char *desc, *mimetype;
77 int nb_packets, packet_total_size, packet_max_size, size, packet_avg_size, i;
78 int bit_rate, v, duration, flags;
80 AVDictionaryEntry *tag;
82 ffio_wfourcc(s, ".RMF");
83 avio_wb32(s,18); /* header size */
86 avio_wb32(s,4 + ctx->nb_streams); /* num headers */
88 ffio_wfourcc(s,"PROP");
92 packet_total_size = 0;
96 for(i=0;i<ctx->nb_streams;i++) {
97 StreamInfo *stream = &rm->streams[i];
98 bit_rate += stream->bit_rate;
99 if (stream->packet_max_size > packet_max_size)
100 packet_max_size = stream->packet_max_size;
101 nb_packets += stream->nb_packets;
102 packet_total_size += stream->packet_total_size;
103 /* select maximum duration */
104 v = av_rescale_q_rnd(stream->total_frames, (AVRational){1000, 1}, stream->frame_rate, AV_ROUND_ZERO);
108 avio_wb32(s, bit_rate); /* max bit rate */
109 avio_wb32(s, bit_rate); /* avg bit rate */
110 avio_wb32(s, packet_max_size); /* max packet size */
112 packet_avg_size = packet_total_size / nb_packets;
115 avio_wb32(s, packet_avg_size); /* avg packet size */
116 avio_wb32(s, nb_packets); /* num packets */
117 avio_wb32(s, duration); /* duration */
118 avio_wb32(s, BUFFER_DURATION); /* preroll */
119 avio_wb32(s, index_pos); /* index offset */
120 /* computation of data the data offset */
121 data_offset = avio_tell(s);
122 avio_wb32(s, 0); /* data offset : will be patched after */
123 avio_wb16(s, ctx->nb_streams); /* num streams */
124 flags = 1 | 2; /* save allowed & perfect play */
125 if (!(s->seekable & AVIO_SEEKABLE_NORMAL))
126 flags |= 4; /* live broadcast */
131 ffio_wfourcc(s,"CONT");
133 for(i=0; i<FF_ARRAY_ELEMS(ff_rm_metadata); i++) {
134 tag = av_dict_get(ctx->metadata, ff_rm_metadata[i], NULL, 0);
135 if(tag) size += strlen(tag->value);
139 for(i=0; i<FF_ARRAY_ELEMS(ff_rm_metadata); i++) {
140 tag = av_dict_get(ctx->metadata, ff_rm_metadata[i], NULL, 0);
141 put_str(s, tag ? tag->value : "");
144 for(i=0;i<ctx->nb_streams;i++) {
147 stream = &rm->streams[i];
149 if (stream->par->codec_type == AVMEDIA_TYPE_AUDIO) {
150 desc = "The Audio Stream";
151 mimetype = "audio/x-pn-realaudio";
152 codec_data_size = 73;
154 desc = "The Video Stream";
155 mimetype = "video/x-pn-realvideo";
156 codec_data_size = 34;
159 ffio_wfourcc(s,"MDPR");
160 size = 10 + 9 * 4 + strlen(desc) + strlen(mimetype) + codec_data_size;
164 avio_wb16(s, i); /* stream number */
165 avio_wb32(s, stream->bit_rate); /* max bit rate */
166 avio_wb32(s, stream->bit_rate); /* avg bit rate */
167 avio_wb32(s, stream->packet_max_size); /* max packet size */
168 if (stream->nb_packets > 0)
169 packet_avg_size = stream->packet_total_size /
173 avio_wb32(s, packet_avg_size); /* avg packet size */
174 avio_wb32(s, 0); /* start time */
175 avio_wb32(s, BUFFER_DURATION); /* preroll */
177 if (!(s->seekable & AVIO_SEEKABLE_NORMAL) || !stream->total_frames)
178 avio_wb32(s, (int)(3600 * 1000));
180 avio_wb32(s, av_rescale_q_rnd(stream->total_frames, (AVRational){1000, 1}, stream->frame_rate, AV_ROUND_ZERO));
182 put_str8(s, mimetype);
183 avio_wb32(s, codec_data_size);
185 if (stream->par->codec_type == AVMEDIA_TYPE_AUDIO) {
186 int coded_frame_size, fscode, sample_rate;
187 int frame_size = av_get_audio_frame_duration2(stream->par, 0);
188 sample_rate = stream->par->sample_rate;
189 coded_frame_size = (stream->par->bit_rate *
190 frame_size) / (8 * sample_rate);
191 /* audio codec info */
192 avio_write(s, ".ra", 3);
194 avio_wb32(s, 0x00040000); /* version */
195 ffio_wfourcc(s, ".ra4");
196 avio_wb32(s, 0x01b53530); /* stream length */
197 avio_wb16(s, 4); /* unknown */
198 avio_wb32(s, 0x39); /* header size */
200 switch(sample_rate) {
217 avio_wb16(s, fscode); /* codec additional info, for AC-3, seems
218 to be a frequency code */
219 /* special hack to compensate rounding errors... */
220 if (coded_frame_size == 557)
222 avio_wb32(s, coded_frame_size); /* frame length */
223 avio_wb32(s, 0x51540); /* unknown */
224 avio_wb32(s, stream->par->bit_rate / 8 * 60); /* bytes per minute */
225 avio_wb32(s, stream->par->bit_rate / 8 * 60); /* bytes per minute */
227 /* frame length : seems to be very important */
228 avio_wb16(s, coded_frame_size);
229 avio_wb32(s, 0); /* unknown */
230 avio_wb16(s, stream->par->sample_rate); /* sample rate */
231 avio_wb32(s, 0x10); /* unknown */
232 avio_wb16(s, stream->par->ch_layout.nb_channels);
233 put_str8(s, "Int0"); /* codec name */
234 if (stream->par->codec_tag) {
235 avio_w8(s, 4); /* tag length */
236 avio_wl32(s, stream->par->codec_tag);
238 av_log(ctx, AV_LOG_ERROR, "Invalid codec tag\n");
241 avio_wb16(s, 0); /* title length */
242 avio_wb16(s, 0); /* author length */
243 avio_wb16(s, 0); /* copyright length */
244 avio_w8(s, 0); /* end of header */
246 /* video codec info */
247 avio_wb32(s,34); /* size */
248 ffio_wfourcc(s, "VIDO");
249 if(stream->par->codec_id == AV_CODEC_ID_RV10)
250 ffio_wfourcc(s,"RV10");
252 ffio_wfourcc(s,"RV20");
253 avio_wb16(s, stream->par->width);
254 avio_wb16(s, stream->par->height);
256 if (stream->frame_rate.num / stream->frame_rate.den > 65535) {
257 av_log(s, AV_LOG_ERROR, "Frame rate %d is too high\n", stream->frame_rate.num / stream->frame_rate.den);
258 return AVERROR(EINVAL);
261 avio_wb16(s, stream->frame_rate.num / stream->frame_rate.den); /* frames per seconds ? */
262 avio_wb32(s,0); /* unknown meaning */
263 avio_wb16(s, stream->frame_rate.num / stream->frame_rate.den); /* unknown meaning */
264 avio_wb32(s,0); /* unknown meaning */
265 avio_wb16(s, 8); /* unknown meaning */
266 /* Seems to be the codec version: only use basic H.263. The next
267 versions seems to add a differential DC coding as in
268 MPEG... nothing new under the sun. */
269 if(stream->par->codec_id == AV_CODEC_ID_RV10)
270 avio_wb32(s,0x10000000);
272 avio_wb32(s,0x20103001);
273 //avio_wb32(s,0x10003000);
277 /* patch data offset field */
278 rm->data_pos = avio_tell(s);
279 if (avio_seek(s, data_offset, SEEK_SET) >= 0) {
280 avio_wb32(s, rm->data_pos);
281 avio_seek(s, rm->data_pos, SEEK_SET);
285 ffio_wfourcc(s, "DATA");
286 avio_wb32(s,data_size + 10 + 8);
289 avio_wb32(s, nb_packets); /* number of packets */
290 avio_wb32(s,0); /* next data header */
294 static void write_packet_header(AVFormatContext *ctx, StreamInfo *stream,
295 int length, int key_frame)
298 AVIOContext *s = ctx->pb;
300 stream->nb_packets++;
301 stream->packet_total_size += length;
302 if (length > stream->packet_max_size)
303 stream->packet_max_size = length;
305 avio_wb16(s,0); /* version */
306 avio_wb16(s,length + 12);
307 avio_wb16(s, stream->num); /* stream number */
308 timestamp = av_rescale_q_rnd(stream->nb_frames, (AVRational){1000, 1}, stream->frame_rate, AV_ROUND_ZERO);
309 avio_wb32(s, timestamp); /* timestamp */
310 avio_w8(s, 0); /* reserved */
311 avio_w8(s, key_frame ? 2 : 0); /* flags */
314 static int rm_write_header(AVFormatContext *s)
316 RMMuxContext *rm = s->priv_data;
319 AVCodecParameters *par;
321 if (s->nb_streams > 2) {
322 av_log(s, AV_LOG_ERROR, "At most 2 streams are currently supported for muxing in RM\n");
323 return AVERROR_PATCHWELCOME;
326 for(n=0;n<s->nb_streams;n++) {
327 AVStream *st = s->streams[n];
330 s->streams[n]->id = n;
331 par = s->streams[n]->codecpar;
332 stream = &rm->streams[n];
333 memset(stream, 0, sizeof(StreamInfo));
335 stream->bit_rate = par->bit_rate;
338 switch (par->codec_type) {
339 case AVMEDIA_TYPE_AUDIO:
340 rm->audio_stream = stream;
341 frame_size = av_get_audio_frame_duration2(par, 0);
342 stream->frame_rate = (AVRational){par->sample_rate, frame_size};
343 /* XXX: dummy values */
344 stream->packet_max_size = 1024;
345 stream->nb_packets = 0;
346 stream->total_frames = stream->nb_packets;
348 case AVMEDIA_TYPE_VIDEO:
349 rm->video_stream = stream;
350 // TODO: should be avg_frame_rate
351 stream->frame_rate = av_inv_q(st->time_base);
352 /* XXX: dummy values */
353 stream->packet_max_size = 4096;
354 stream->nb_packets = 0;
355 stream->total_frames = stream->nb_packets;
362 if (rv10_write_header(s, 0, 0))
363 return AVERROR_INVALIDDATA;
367 static int rm_write_audio(AVFormatContext *s, const uint8_t *buf, int size, int flags)
369 RMMuxContext *rm = s->priv_data;
370 AVIOContext *pb = s->pb;
371 StreamInfo *stream = rm->audio_stream;
374 write_packet_header(s, stream, size, !!(flags & AV_PKT_FLAG_KEY));
376 if (stream->par->codec_id == AV_CODEC_ID_AC3) {
377 /* for AC-3, the words seem to be reversed */
378 for (i = 0; i < size; i += 2) {
379 avio_w8(pb, buf[i + 1]);
383 avio_write(pb, buf, size);
389 static int rm_write_video(AVFormatContext *s, const uint8_t *buf, int size, int flags)
391 RMMuxContext *rm = s->priv_data;
392 AVIOContext *pb = s->pb;
393 StreamInfo *stream = rm->video_stream;
394 int key_frame = !!(flags & AV_PKT_FLAG_KEY);
396 /* XXX: this is incorrect: should be a parameter */
398 /* Well, I spent some time finding the meaning of these bits. I am
399 not sure I understood everything, but it works !! */
400 if (size > MAX_PACKET_SIZE) {
401 av_log(s, AV_LOG_ERROR, "Muxing packets larger than 64 kB (%d) is not supported\n", size);
402 return AVERROR_PATCHWELCOME;
404 write_packet_header(s, stream, size + 7 + (size >= 0x4000)*4, key_frame);
405 /* bit 7: '1' if final packet of a frame converted in several packets */
407 /* bit 7: '1' if I-frame. bits 6..0 : sequence number in current
408 frame starting from 1 */
415 avio_wb32(pb, size); /* total frame size */
416 avio_wb32(pb, size); /* offset from the start or the end */
418 avio_wb16(pb, 0x4000 | size); /* total frame size */
419 avio_wb16(pb, 0x4000 | size); /* offset from the start or the end */
421 avio_w8(pb, stream->nb_frames & 0xff);
423 avio_write(pb, buf, size);
429 static int rm_write_packet(AVFormatContext *s, AVPacket *pkt)
431 if (s->streams[pkt->stream_index]->codecpar->codec_type ==
433 return rm_write_audio(s, pkt->data, pkt->size, pkt->flags);
435 return rm_write_video(s, pkt->data, pkt->size, pkt->flags);
438 static int rm_write_trailer(AVFormatContext *s)
440 RMMuxContext *rm = s->priv_data;
441 int data_size, index_pos, i;
442 AVIOContext *pb = s->pb;
444 if (s->pb->seekable & AVIO_SEEKABLE_NORMAL) {
445 /* end of file: finish to write header */
446 index_pos = avio_tell(pb);
447 data_size = index_pos - rm->data_pos;
449 /* FIXME: write index */
451 /* undocumented end header */
455 avio_seek(pb, 0, SEEK_SET);
456 for(i=0;i<s->nb_streams;i++)
457 rm->streams[i].total_frames = rm->streams[i].nb_frames;
458 rv10_write_header(s, data_size, 0);
460 /* undocumented end header */
469 const FFOutputFormat ff_rm_muxer = {
471 .p.long_name = NULL_IF_CONFIG_SMALL("RealMedia"),
472 .p.mime_type = "application/vnd.rn-realmedia",
473 .p.extensions = "rm,ra",
474 .priv_data_size = sizeof(RMMuxContext),
475 .p.audio_codec = AV_CODEC_ID_AC3,
476 .p.video_codec = AV_CODEC_ID_RV10,
477 .write_header = rm_write_header,
478 .write_packet = rm_write_packet,
479 .write_trailer = rm_write_trailer,
480 .p.codec_tag = (const AVCodecTag* const []){ ff_rm_codec_tags, 0 },