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"
24 #include "libavutil/dict.h"
26 typedef struct StreamInfo {
28 int packet_total_size;
30 /* codec related output */
33 int nb_frames; /* current frame number */
34 int total_frames; /* total number of frames */
39 typedef struct RMMuxContext {
40 StreamInfo streams[2];
41 StreamInfo *audio_stream, *video_stream;
42 int data_pos; /* position of the data after the header */
46 #define BUFFER_DURATION 0
47 /* the header needs at most 7 + 4 + 12 B */
48 #define MAX_HEADER_SIZE (7 + 4 + 12)
49 /* UINT16_MAX is the maximal chunk size */
50 #define MAX_PACKET_SIZE (UINT16_MAX - MAX_HEADER_SIZE)
53 static void put_str(AVIOContext *s, const char *tag)
55 avio_wb16(s,strlen(tag));
61 static void put_str8(AVIOContext *s, const char *tag)
63 avio_w8(s, strlen(tag));
69 static int rv10_write_header(AVFormatContext *ctx,
70 int data_size, int index_pos)
72 RMMuxContext *rm = ctx->priv_data;
73 AVIOContext *s = ctx->pb;
75 unsigned char *data_offset_ptr, *start_ptr;
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, data_pos;
79 AVDictionaryEntry *tag;
81 start_ptr = s->buf_ptr;
83 ffio_wfourcc(s, ".RMF");
84 avio_wb32(s,18); /* header size */
87 avio_wb32(s,4 + ctx->nb_streams); /* num headers */
89 ffio_wfourcc(s,"PROP");
93 packet_total_size = 0;
97 for(i=0;i<ctx->nb_streams;i++) {
98 StreamInfo *stream = &rm->streams[i];
99 bit_rate += stream->bit_rate;
100 if (stream->packet_max_size > packet_max_size)
101 packet_max_size = stream->packet_max_size;
102 nb_packets += stream->nb_packets;
103 packet_total_size += stream->packet_total_size;
104 /* select maximum duration */
105 v = (int) (1000.0 * (float)stream->total_frames / stream->frame_rate);
109 avio_wb32(s, bit_rate); /* max bit rate */
110 avio_wb32(s, bit_rate); /* avg bit rate */
111 avio_wb32(s, packet_max_size); /* max packet size */
113 packet_avg_size = packet_total_size / nb_packets;
116 avio_wb32(s, packet_avg_size); /* avg packet size */
117 avio_wb32(s, nb_packets); /* num packets */
118 avio_wb32(s, duration); /* duration */
119 avio_wb32(s, BUFFER_DURATION); /* preroll */
120 avio_wb32(s, index_pos); /* index offset */
121 /* computation of data the data offset */
122 data_offset_ptr = s->buf_ptr;
123 avio_wb32(s, 0); /* data offset : will be patched after */
124 avio_wb16(s, ctx->nb_streams); /* num streams */
125 flags = 1 | 2; /* save allowed & perfect play */
127 flags |= 4; /* live broadcast */
132 ffio_wfourcc(s,"CONT");
134 for(i=0; i<FF_ARRAY_ELEMS(ff_rm_metadata); i++) {
135 tag = av_dict_get(ctx->metadata, ff_rm_metadata[i], NULL, 0);
136 if(tag) size += strlen(tag->value);
140 for(i=0; i<FF_ARRAY_ELEMS(ff_rm_metadata); i++) {
141 tag = av_dict_get(ctx->metadata, ff_rm_metadata[i], NULL, 0);
142 put_str(s, tag ? tag->value : "");
145 for(i=0;i<ctx->nb_streams;i++) {
148 stream = &rm->streams[i];
150 if (stream->enc->codec_type == AVMEDIA_TYPE_AUDIO) {
151 desc = "The Audio Stream";
152 mimetype = "audio/x-pn-realaudio";
153 codec_data_size = 73;
155 desc = "The Video Stream";
156 mimetype = "video/x-pn-realvideo";
157 codec_data_size = 34;
160 ffio_wfourcc(s,"MDPR");
161 size = 10 + 9 * 4 + strlen(desc) + strlen(mimetype) + codec_data_size;
165 avio_wb16(s, i); /* stream number */
166 avio_wb32(s, stream->bit_rate); /* max bit rate */
167 avio_wb32(s, stream->bit_rate); /* avg bit rate */
168 avio_wb32(s, stream->packet_max_size); /* max packet size */
169 if (stream->nb_packets > 0)
170 packet_avg_size = stream->packet_total_size /
174 avio_wb32(s, packet_avg_size); /* avg packet size */
175 avio_wb32(s, 0); /* start time */
176 avio_wb32(s, BUFFER_DURATION); /* preroll */
178 if (!s->seekable || !stream->total_frames)
179 avio_wb32(s, (int)(3600 * 1000));
181 avio_wb32(s, (int)(stream->total_frames * 1000 / stream->frame_rate));
183 put_str8(s, mimetype);
184 avio_wb32(s, codec_data_size);
186 if (stream->enc->codec_type == AVMEDIA_TYPE_AUDIO) {
187 int coded_frame_size, fscode, sample_rate;
188 sample_rate = stream->enc->sample_rate;
189 coded_frame_size = (stream->enc->bit_rate *
190 stream->enc->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->enc->bit_rate / 8 * 60); /* bytes per minute */
225 avio_wb32(s, stream->enc->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->enc->sample_rate); /* sample rate */
231 avio_wb32(s, 0x10); /* unknown */
232 avio_wb16(s, stream->enc->channels);
233 put_str8(s, "Int0"); /* codec name */
234 if (stream->enc->codec_tag) {
235 avio_w8(s, 4); /* tag length */
236 avio_wl32(s, stream->enc->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->enc->codec_id == AV_CODEC_ID_RV10)
250 ffio_wfourcc(s,"RV10");
252 ffio_wfourcc(s,"RV20");
253 avio_wb16(s, stream->enc->width);
254 avio_wb16(s, stream->enc->height);
255 avio_wb16(s, (int) stream->frame_rate); /* frames per seconds ? */
256 avio_wb32(s,0); /* unknown meaning */
257 avio_wb16(s, (int) stream->frame_rate); /* unknown meaning */
258 avio_wb32(s,0); /* unknown meaning */
259 avio_wb16(s, 8); /* unknown meaning */
260 /* Seems to be the codec version: only use basic H263. The next
261 versions seems to add a diffential DC coding as in
262 MPEG... nothing new under the sun */
263 if(stream->enc->codec_id == AV_CODEC_ID_RV10)
264 avio_wb32(s,0x10000000);
266 avio_wb32(s,0x20103001);
267 //avio_wb32(s,0x10003000);
271 /* patch data offset field */
272 data_pos = s->buf_ptr - start_ptr;
273 rm->data_pos = data_pos;
274 data_offset_ptr[0] = data_pos >> 24;
275 data_offset_ptr[1] = data_pos >> 16;
276 data_offset_ptr[2] = data_pos >> 8;
277 data_offset_ptr[3] = data_pos;
280 ffio_wfourcc(s, "DATA");
281 avio_wb32(s,data_size + 10 + 8);
284 avio_wb32(s, nb_packets); /* number of packets */
285 avio_wb32(s,0); /* next data header */
289 static void write_packet_header(AVFormatContext *ctx, StreamInfo *stream,
290 int length, int key_frame)
293 AVIOContext *s = ctx->pb;
295 stream->nb_packets++;
296 stream->packet_total_size += length;
297 if (length > stream->packet_max_size)
298 stream->packet_max_size = length;
300 avio_wb16(s,0); /* version */
301 avio_wb16(s,length + 12);
302 avio_wb16(s, stream->num); /* stream number */
303 timestamp = (1000 * (float)stream->nb_frames) / stream->frame_rate;
304 avio_wb32(s, timestamp); /* timestamp */
305 avio_w8(s, 0); /* reserved */
306 avio_w8(s, key_frame ? 2 : 0); /* flags */
309 static int rm_write_header(AVFormatContext *s)
311 RMMuxContext *rm = s->priv_data;
314 AVCodecContext *codec;
316 if (s->nb_streams > 2) {
317 av_log(s, AV_LOG_ERROR, "At most 2 streams are currently supported for muxing in RM\n");
318 return AVERROR_PATCHWELCOME;
321 for(n=0;n<s->nb_streams;n++) {
322 AVStream *st = s->streams[n];
324 s->streams[n]->id = n;
325 codec = s->streams[n]->codec;
326 stream = &rm->streams[n];
327 memset(stream, 0, sizeof(StreamInfo));
329 stream->bit_rate = codec->bit_rate;
332 switch(codec->codec_type) {
333 case AVMEDIA_TYPE_AUDIO:
334 rm->audio_stream = stream;
335 stream->frame_rate = (float)codec->sample_rate / (float)codec->frame_size;
336 /* XXX: dummy values */
337 stream->packet_max_size = 1024;
338 stream->nb_packets = 0;
339 stream->total_frames = stream->nb_packets;
341 case AVMEDIA_TYPE_VIDEO:
342 rm->video_stream = stream;
343 // TODO: should be avg_frame_rate
344 stream->frame_rate = (float)st->time_base.den / (float)st->time_base.num;
345 /* XXX: dummy values */
346 stream->packet_max_size = 4096;
347 stream->nb_packets = 0;
348 stream->total_frames = stream->nb_packets;
355 if (rv10_write_header(s, 0, 0))
356 return AVERROR_INVALIDDATA;
361 static int rm_write_audio(AVFormatContext *s, const uint8_t *buf, int size, int flags)
364 RMMuxContext *rm = s->priv_data;
365 AVIOContext *pb = s->pb;
366 StreamInfo *stream = rm->audio_stream;
369 /* XXX: suppress this malloc */
370 buf1 = av_malloc(size * sizeof(uint8_t));
372 return AVERROR(ENOMEM);
374 write_packet_header(s, stream, size, !!(flags & AV_PKT_FLAG_KEY));
376 if (stream->enc->codec_id == AV_CODEC_ID_AC3) {
377 /* for AC-3, the words seem to be reversed */
378 for(i=0;i<size;i+=2) {
382 avio_write(pb, buf1, size);
384 avio_write(pb, buf, size);
391 static int rm_write_video(AVFormatContext *s, const uint8_t *buf, int size, int flags)
393 RMMuxContext *rm = s->priv_data;
394 AVIOContext *pb = s->pb;
395 StreamInfo *stream = rm->video_stream;
396 int key_frame = !!(flags & AV_PKT_FLAG_KEY);
398 /* XXX: this is incorrect: should be a parameter */
400 /* Well, I spent some time finding the meaning of these bits. I am
401 not sure I understood everything, but it works !! */
403 if (size > MAX_PACKET_SIZE) {
404 av_log(s, AV_LOG_ERROR, "Muxing packets larger than 64 kB (%d) is not supported\n", size);
405 return AVERROR_PATCHWELCOME;
407 write_packet_header(s, stream, size + 7 + (size >= 0x4000)*4, key_frame);
408 /* bit 7: '1' if final packet of a frame converted in several packets */
410 /* bit 7: '1' if I frame. bits 6..0 : sequence number in current
411 frame starting from 1 */
418 avio_wb32(pb, size); /* total frame size */
419 avio_wb32(pb, size); /* offset from the start or the end */
421 avio_wb16(pb, 0x4000 | size); /* total frame size */
422 avio_wb16(pb, 0x4000 | size); /* offset from the start or the end */
426 write_packet_header(s, size + 6);
428 avio_wb16(pb, 0x4000 + size); /* total frame size */
429 avio_wb16(pb, 0x4000 + packet_number * 126); /* position in stream */
431 avio_w8(pb, stream->nb_frames & 0xff);
433 avio_write(pb, buf, size);
439 static int rm_write_packet(AVFormatContext *s, AVPacket *pkt)
441 if (s->streams[pkt->stream_index]->codec->codec_type ==
443 return rm_write_audio(s, pkt->data, pkt->size, pkt->flags);
445 return rm_write_video(s, pkt->data, pkt->size, pkt->flags);
448 static int rm_write_trailer(AVFormatContext *s)
450 RMMuxContext *rm = s->priv_data;
451 int data_size, index_pos, i;
452 AVIOContext *pb = s->pb;
454 if (s->pb->seekable) {
455 /* end of file: finish to write header */
456 index_pos = avio_tell(pb);
457 data_size = index_pos - rm->data_pos;
459 /* FIXME: write index */
461 /* undocumented end header */
465 avio_seek(pb, 0, SEEK_SET);
466 for(i=0;i<s->nb_streams;i++)
467 rm->streams[i].total_frames = rm->streams[i].nb_frames;
468 rv10_write_header(s, data_size, 0);
470 /* undocumented end header */
479 AVOutputFormat ff_rm_muxer = {
481 .long_name = NULL_IF_CONFIG_SMALL("RealMedia"),
482 .mime_type = "application/vnd.rn-realmedia",
483 .extensions = "rm,ra",
484 .priv_data_size = sizeof(RMMuxContext),
485 .audio_codec = AV_CODEC_ID_AC3,
486 .video_codec = AV_CODEC_ID_RV10,
487 .write_header = rm_write_header,
488 .write_packet = rm_write_packet,
489 .write_trailer = rm_write_trailer,
490 .codec_tag = (const AVCodecTag* const []){ ff_rm_codec_tags, 0 },