1/*
2 * "Real" compatible muxer.
3 * Copyright (c) 2000, 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#include "avformat.h"
22#include "rm.h"
23
24typedef struct {
25    int nb_packets;
26    int packet_total_size;
27    int packet_max_size;
28    /* codec related output */
29    int bit_rate;
30    float frame_rate;
31    int nb_frames;    /* current frame number */
32    int total_frames; /* total number of frames */
33    int num;
34    AVCodecContext *enc;
35} StreamInfo;
36
37typedef struct {
38    StreamInfo streams[2];
39    StreamInfo *audio_stream, *video_stream;
40    int data_pos; /* position of the data after the header */
41} RMMuxContext;
42
43/* in ms */
44#define BUFFER_DURATION 0
45
46
47static void put_str(ByteIOContext *s, const char *tag)
48{
49    put_be16(s,strlen(tag));
50    while (*tag) {
51        put_byte(s, *tag++);
52    }
53}
54
55static void put_str8(ByteIOContext *s, const char *tag)
56{
57    put_byte(s, strlen(tag));
58    while (*tag) {
59        put_byte(s, *tag++);
60    }
61}
62
63static void rv10_write_header(AVFormatContext *ctx,
64                              int data_size, int index_pos)
65{
66    RMMuxContext *rm = ctx->priv_data;
67    ByteIOContext *s = ctx->pb;
68    StreamInfo *stream;
69    unsigned char *data_offset_ptr, *start_ptr;
70    const char *desc, *mimetype;
71    int nb_packets, packet_total_size, packet_max_size, size, packet_avg_size, i;
72    int bit_rate, v, duration, flags, data_pos;
73    AVMetadataTag *tag;
74
75    start_ptr = s->buf_ptr;
76
77    put_tag(s, ".RMF");
78    put_be32(s,18); /* header size */
79    put_be16(s,0);
80    put_be32(s,0);
81    put_be32(s,4 + ctx->nb_streams); /* num headers */
82
83    put_tag(s,"PROP");
84    put_be32(s, 50);
85    put_be16(s, 0);
86    packet_max_size = 0;
87    packet_total_size = 0;
88    nb_packets = 0;
89    bit_rate = 0;
90    duration = 0;
91    for(i=0;i<ctx->nb_streams;i++) {
92        StreamInfo *stream = &rm->streams[i];
93        bit_rate += stream->bit_rate;
94        if (stream->packet_max_size > packet_max_size)
95            packet_max_size = stream->packet_max_size;
96        nb_packets += stream->nb_packets;
97        packet_total_size += stream->packet_total_size;
98        /* select maximum duration */
99        v = (int) (1000.0 * (float)stream->total_frames / stream->frame_rate);
100        if (v > duration)
101            duration = v;
102    }
103    put_be32(s, bit_rate); /* max bit rate */
104    put_be32(s, bit_rate); /* avg bit rate */
105    put_be32(s, packet_max_size);        /* max packet size */
106    if (nb_packets > 0)
107        packet_avg_size = packet_total_size / nb_packets;
108    else
109        packet_avg_size = 0;
110    put_be32(s, packet_avg_size);        /* avg packet size */
111    put_be32(s, nb_packets);  /* num packets */
112    put_be32(s, duration); /* duration */
113    put_be32(s, BUFFER_DURATION);           /* preroll */
114    put_be32(s, index_pos);           /* index offset */
115    /* computation of data the data offset */
116    data_offset_ptr = s->buf_ptr;
117    put_be32(s, 0);           /* data offset : will be patched after */
118    put_be16(s, ctx->nb_streams);    /* num streams */
119    flags = 1 | 2; /* save allowed & perfect play */
120    if (url_is_streamed(s))
121        flags |= 4; /* live broadcast */
122    put_be16(s, flags);
123
124    /* comments */
125
126    put_tag(s,"CONT");
127    size =  4 * 2 + 10;
128    for(i=0; i<FF_ARRAY_ELEMS(ff_rm_metadata); i++) {
129        tag = av_metadata_get(ctx->metadata, ff_rm_metadata[i], NULL, 0);
130        if(tag) size += strlen(tag->value);
131    }
132    put_be32(s,size);
133    put_be16(s,0);
134    for(i=0; i<FF_ARRAY_ELEMS(ff_rm_metadata); i++) {
135        tag = av_metadata_get(ctx->metadata, ff_rm_metadata[i], NULL, 0);
136        put_str(s, tag ? tag->value : "");
137    }
138
139    for(i=0;i<ctx->nb_streams;i++) {
140        int codec_data_size;
141
142        stream = &rm->streams[i];
143
144        if (stream->enc->codec_type == CODEC_TYPE_AUDIO) {
145            desc = "The Audio Stream";
146            mimetype = "audio/x-pn-realaudio";
147            codec_data_size = 73;
148        } else {
149            desc = "The Video Stream";
150            mimetype = "video/x-pn-realvideo";
151            codec_data_size = 34;
152        }
153
154        put_tag(s,"MDPR");
155        size = 10 + 9 * 4 + strlen(desc) + strlen(mimetype) + codec_data_size;
156        put_be32(s, size);
157        put_be16(s, 0);
158
159        put_be16(s, i); /* stream number */
160        put_be32(s, stream->bit_rate); /* max bit rate */
161        put_be32(s, stream->bit_rate); /* avg bit rate */
162        put_be32(s, stream->packet_max_size);        /* max packet size */
163        if (stream->nb_packets > 0)
164            packet_avg_size = stream->packet_total_size /
165                stream->nb_packets;
166        else
167            packet_avg_size = 0;
168        put_be32(s, packet_avg_size);        /* avg packet size */
169        put_be32(s, 0);           /* start time */
170        put_be32(s, BUFFER_DURATION);           /* preroll */
171        /* duration */
172        if (url_is_streamed(s) || !stream->total_frames)
173            put_be32(s, (int)(3600 * 1000));
174        else
175            put_be32(s, (int)(stream->total_frames * 1000 / stream->frame_rate));
176        put_str8(s, desc);
177        put_str8(s, mimetype);
178        put_be32(s, codec_data_size);
179
180        if (stream->enc->codec_type == CODEC_TYPE_AUDIO) {
181            int coded_frame_size, fscode, sample_rate;
182            sample_rate = stream->enc->sample_rate;
183            coded_frame_size = (stream->enc->bit_rate *
184                                stream->enc->frame_size) / (8 * sample_rate);
185            /* audio codec info */
186            put_tag(s, ".ra");
187            put_byte(s, 0xfd);
188            put_be32(s, 0x00040000); /* version */
189            put_tag(s, ".ra4");
190            put_be32(s, 0x01b53530); /* stream length */
191            put_be16(s, 4); /* unknown */
192            put_be32(s, 0x39); /* header size */
193
194            switch(sample_rate) {
195            case 48000:
196            case 24000:
197            case 12000:
198                fscode = 1;
199                break;
200            default:
201            case 44100:
202            case 22050:
203            case 11025:
204                fscode = 2;
205                break;
206            case 32000:
207            case 16000:
208            case 8000:
209                fscode = 3;
210            }
211            put_be16(s, fscode); /* codec additional info, for AC-3, seems
212                                     to be a frequency code */
213            /* special hack to compensate rounding errors... */
214            if (coded_frame_size == 557)
215                coded_frame_size--;
216            put_be32(s, coded_frame_size); /* frame length */
217            put_be32(s, 0x51540); /* unknown */
218            put_be32(s, 0x249f0); /* unknown */
219            put_be32(s, 0x249f0); /* unknown */
220            put_be16(s, 0x01);
221            /* frame length : seems to be very important */
222            put_be16(s, coded_frame_size);
223            put_be32(s, 0); /* unknown */
224            put_be16(s, stream->enc->sample_rate); /* sample rate */
225            put_be32(s, 0x10); /* unknown */
226            put_be16(s, stream->enc->channels);
227            put_str8(s, "Int0"); /* codec name */
228            put_str8(s, "dnet"); /* codec name */
229            put_be16(s, 0); /* title length */
230            put_be16(s, 0); /* author length */
231            put_be16(s, 0); /* copyright length */
232            put_byte(s, 0); /* end of header */
233        } else {
234            /* video codec info */
235            put_be32(s,34); /* size */
236            if(stream->enc->codec_id == CODEC_ID_RV10)
237                put_tag(s,"VIDORV10");
238            else
239                put_tag(s,"VIDORV20");
240            put_be16(s, stream->enc->width);
241            put_be16(s, stream->enc->height);
242            put_be16(s, (int) stream->frame_rate); /* frames per seconds ? */
243            put_be32(s,0);     /* unknown meaning */
244            put_be16(s, (int) stream->frame_rate);  /* unknown meaning */
245            put_be32(s,0);     /* unknown meaning */
246            put_be16(s, 8);    /* unknown meaning */
247            /* Seems to be the codec version: only use basic H263. The next
248               versions seems to add a diffential DC coding as in
249               MPEG... nothing new under the sun */
250            if(stream->enc->codec_id == CODEC_ID_RV10)
251                put_be32(s,0x10000000);
252            else
253                put_be32(s,0x20103001);
254            //put_be32(s,0x10003000);
255        }
256    }
257
258    /* patch data offset field */
259    data_pos = s->buf_ptr - start_ptr;
260    rm->data_pos = data_pos;
261    data_offset_ptr[0] = data_pos >> 24;
262    data_offset_ptr[1] = data_pos >> 16;
263    data_offset_ptr[2] = data_pos >> 8;
264    data_offset_ptr[3] = data_pos;
265
266    /* data stream */
267    put_tag(s,"DATA");
268    put_be32(s,data_size + 10 + 8);
269    put_be16(s,0);
270
271    put_be32(s, nb_packets); /* number of packets */
272    put_be32(s,0); /* next data header */
273}
274
275static void write_packet_header(AVFormatContext *ctx, StreamInfo *stream,
276                                int length, int key_frame)
277{
278    int timestamp;
279    ByteIOContext *s = ctx->pb;
280
281    stream->nb_packets++;
282    stream->packet_total_size += length;
283    if (length > stream->packet_max_size)
284        stream->packet_max_size =  length;
285
286    put_be16(s,0); /* version */
287    put_be16(s,length + 12);
288    put_be16(s, stream->num); /* stream number */
289    timestamp = (1000 * (float)stream->nb_frames) / stream->frame_rate;
290    put_be32(s, timestamp); /* timestamp */
291    put_byte(s, 0); /* reserved */
292    put_byte(s, key_frame ? 2 : 0); /* flags */
293}
294
295static int rm_write_header(AVFormatContext *s)
296{
297    RMMuxContext *rm = s->priv_data;
298    StreamInfo *stream;
299    int n;
300    AVCodecContext *codec;
301
302    for(n=0;n<s->nb_streams;n++) {
303        s->streams[n]->id = n;
304        codec = s->streams[n]->codec;
305        stream = &rm->streams[n];
306        memset(stream, 0, sizeof(StreamInfo));
307        stream->num = n;
308        stream->bit_rate = codec->bit_rate;
309        stream->enc = codec;
310
311        switch(codec->codec_type) {
312        case CODEC_TYPE_AUDIO:
313            rm->audio_stream = stream;
314            stream->frame_rate = (float)codec->sample_rate / (float)codec->frame_size;
315            /* XXX: dummy values */
316            stream->packet_max_size = 1024;
317            stream->nb_packets = 0;
318            stream->total_frames = stream->nb_packets;
319            break;
320        case CODEC_TYPE_VIDEO:
321            rm->video_stream = stream;
322            stream->frame_rate = (float)codec->time_base.den / (float)codec->time_base.num;
323            /* XXX: dummy values */
324            stream->packet_max_size = 4096;
325            stream->nb_packets = 0;
326            stream->total_frames = stream->nb_packets;
327            break;
328        default:
329            return -1;
330        }
331    }
332
333    rv10_write_header(s, 0, 0);
334    put_flush_packet(s->pb);
335    return 0;
336}
337
338static int rm_write_audio(AVFormatContext *s, const uint8_t *buf, int size, int flags)
339{
340    uint8_t *buf1;
341    RMMuxContext *rm = s->priv_data;
342    ByteIOContext *pb = s->pb;
343    StreamInfo *stream = rm->audio_stream;
344    int i;
345
346    /* XXX: suppress this malloc */
347    buf1= (uint8_t*) av_malloc( size * sizeof(uint8_t) );
348
349    write_packet_header(s, stream, size, !!(flags & PKT_FLAG_KEY));
350
351    /* for AC-3, the words seem to be reversed */
352    for(i=0;i<size;i+=2) {
353        buf1[i] = buf[i+1];
354        buf1[i+1] = buf[i];
355    }
356    put_buffer(pb, buf1, size);
357    put_flush_packet(pb);
358    stream->nb_frames++;
359    av_free(buf1);
360    return 0;
361}
362
363static int rm_write_video(AVFormatContext *s, const uint8_t *buf, int size, int flags)
364{
365    RMMuxContext *rm = s->priv_data;
366    ByteIOContext *pb = s->pb;
367    StreamInfo *stream = rm->video_stream;
368    int key_frame = !!(flags & PKT_FLAG_KEY);
369
370    /* XXX: this is incorrect: should be a parameter */
371
372    /* Well, I spent some time finding the meaning of these bits. I am
373       not sure I understood everything, but it works !! */
374#if 1
375    write_packet_header(s, stream, size + 7 + (size >= 0x4000)*4, key_frame);
376    /* bit 7: '1' if final packet of a frame converted in several packets */
377    put_byte(pb, 0x81);
378    /* bit 7: '1' if I frame. bits 6..0 : sequence number in current
379       frame starting from 1 */
380    if (key_frame) {
381        put_byte(pb, 0x81);
382    } else {
383        put_byte(pb, 0x01);
384    }
385    if(size >= 0x4000){
386        put_be32(pb, size); /* total frame size */
387        put_be32(pb, size); /* offset from the start or the end */
388    }else{
389        put_be16(pb, 0x4000 | size); /* total frame size */
390        put_be16(pb, 0x4000 | size); /* offset from the start or the end */
391    }
392#else
393    /* full frame */
394    write_packet_header(s, size + 6);
395    put_byte(pb, 0xc0);
396    put_be16(pb, 0x4000 + size); /* total frame size */
397    put_be16(pb, 0x4000 + packet_number * 126); /* position in stream */
398#endif
399    put_byte(pb, stream->nb_frames & 0xff);
400
401    put_buffer(pb, buf, size);
402    put_flush_packet(pb);
403
404    stream->nb_frames++;
405    return 0;
406}
407
408static int rm_write_packet(AVFormatContext *s, AVPacket *pkt)
409{
410    if (s->streams[pkt->stream_index]->codec->codec_type ==
411        CODEC_TYPE_AUDIO)
412        return rm_write_audio(s, pkt->data, pkt->size, pkt->flags);
413    else
414        return rm_write_video(s, pkt->data, pkt->size, pkt->flags);
415}
416
417static int rm_write_trailer(AVFormatContext *s)
418{
419    RMMuxContext *rm = s->priv_data;
420    int data_size, index_pos, i;
421    ByteIOContext *pb = s->pb;
422
423    if (!url_is_streamed(s->pb)) {
424        /* end of file: finish to write header */
425        index_pos = url_fseek(pb, 0, SEEK_CUR);
426        data_size = index_pos - rm->data_pos;
427
428        /* index */
429        put_tag(pb, "INDX");
430        put_be32(pb, 10 + 10 * s->nb_streams);
431        put_be16(pb, 0);
432
433        for(i=0;i<s->nb_streams;i++) {
434            put_be32(pb, 0); /* zero indexes */
435            put_be16(pb, i); /* stream number */
436            put_be32(pb, 0); /* next index */
437        }
438        /* undocumented end header */
439        put_be32(pb, 0);
440        put_be32(pb, 0);
441
442        url_fseek(pb, 0, SEEK_SET);
443        for(i=0;i<s->nb_streams;i++)
444            rm->streams[i].total_frames = rm->streams[i].nb_frames;
445        rv10_write_header(s, data_size, index_pos);
446    } else {
447        /* undocumented end header */
448        put_be32(pb, 0);
449        put_be32(pb, 0);
450    }
451    put_flush_packet(pb);
452    return 0;
453}
454
455
456AVOutputFormat rm_muxer = {
457    "rm",
458    NULL_IF_CONFIG_SMALL("RealMedia format"),
459    "application/vnd.rn-realmedia",
460    "rm,ra",
461    sizeof(RMMuxContext),
462    CODEC_ID_AC3,
463    CODEC_ID_RV10,
464    rm_write_header,
465    rm_write_packet,
466    rm_write_trailer,
467};
468