libavformat/dvenc.c
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00001 /*
00002  * General DV muxer/demuxer
00003  * Copyright (c) 2003 Roman Shaposhnik
00004  *
00005  * Many thanks to Dan Dennedy <dan@dennedy.org> for providing wealth
00006  * of DV technical info.
00007  *
00008  * Raw DV format
00009  * Copyright (c) 2002 Fabrice Bellard
00010  *
00011  * 50 Mbps (DVCPRO50) support
00012  * Copyright (c) 2006 Daniel Maas <dmaas@maasdigital.com>
00013  *
00014  * This file is part of FFmpeg.
00015  *
00016  * FFmpeg is free software; you can redistribute it and/or
00017  * modify it under the terms of the GNU Lesser General Public
00018  * License as published by the Free Software Foundation; either
00019  * version 2.1 of the License, or (at your option) any later version.
00020  *
00021  * FFmpeg is distributed in the hope that it will be useful,
00022  * but WITHOUT ANY WARRANTY; without even the implied warranty of
00023  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
00024  * Lesser General Public License for more details.
00025  *
00026  * You should have received a copy of the GNU Lesser General Public
00027  * License along with FFmpeg; if not, write to the Free Software
00028  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
00029  */
00030 #include <time.h>
00031 #include <stdarg.h>
00032 
00033 #include "avformat.h"
00034 #include "internal.h"
00035 #include "libavcodec/dvdata.h"
00036 #include "libavcodec/timecode.h"
00037 #include "dv.h"
00038 #include "libavutil/fifo.h"
00039 #include "libavutil/mathematics.h"
00040 #include "libavutil/intreadwrite.h"
00041 #include "libavutil/opt.h"
00042 
00043 struct DVMuxContext {
00044     AVClass          *av_class;
00045     const DVprofile*  sys;           /* current DV profile, e.g.: 525/60, 625/50 */
00046     int               n_ast;         /* number of stereo audio streams (up to 2) */
00047     AVStream         *ast[2];        /* stereo audio streams */
00048     AVFifoBuffer     *audio_data[2]; /* FIFO for storing excessive amounts of PCM */
00049     int               frames;        /* current frame number */
00050     int64_t           start_time;    /* recording start time */
00051     int               has_audio;     /* frame under contruction has audio */
00052     int               has_video;     /* frame under contruction has video */
00053     uint8_t           frame_buf[DV_MAX_FRAME_SIZE]; /* frame under contruction */
00054     struct ff_timecode tc;
00055 };
00056 
00057 static const int dv_aaux_packs_dist[12][9] = {
00058     { 0xff, 0xff, 0xff, 0x50, 0x51, 0x52, 0x53, 0xff, 0xff },
00059     { 0x50, 0x51, 0x52, 0x53, 0xff, 0xff, 0xff, 0xff, 0xff },
00060     { 0xff, 0xff, 0xff, 0x50, 0x51, 0x52, 0x53, 0xff, 0xff },
00061     { 0x50, 0x51, 0x52, 0x53, 0xff, 0xff, 0xff, 0xff, 0xff },
00062     { 0xff, 0xff, 0xff, 0x50, 0x51, 0x52, 0x53, 0xff, 0xff },
00063     { 0x50, 0x51, 0x52, 0x53, 0xff, 0xff, 0xff, 0xff, 0xff },
00064     { 0xff, 0xff, 0xff, 0x50, 0x51, 0x52, 0x53, 0xff, 0xff },
00065     { 0x50, 0x51, 0x52, 0x53, 0xff, 0xff, 0xff, 0xff, 0xff },
00066     { 0xff, 0xff, 0xff, 0x50, 0x51, 0x52, 0x53, 0xff, 0xff },
00067     { 0x50, 0x51, 0x52, 0x53, 0xff, 0xff, 0xff, 0xff, 0xff },
00068     { 0xff, 0xff, 0xff, 0x50, 0x51, 0x52, 0x53, 0xff, 0xff },
00069     { 0x50, 0x51, 0x52, 0x53, 0xff, 0xff, 0xff, 0xff, 0xff },
00070 };
00071 
00072 static int dv_audio_frame_size(const DVprofile* sys, int frame)
00073 {
00074     return sys->audio_samples_dist[frame % (sizeof(sys->audio_samples_dist) /
00075                                             sizeof(sys->audio_samples_dist[0]))];
00076 }
00077 
00078 static int dv_write_pack(enum dv_pack_type pack_id, DVMuxContext *c, uint8_t* buf, ...)
00079 {
00080     struct tm tc;
00081     time_t ct;
00082     int ltc_frame;
00083     uint32_t timecode;
00084     va_list ap;
00085 
00086     buf[0] = (uint8_t)pack_id;
00087     switch (pack_id) {
00088     case dv_timecode:
00089         /*
00090          * LTC drop-frame frame counter drops two frames (0 and 1) every
00091          * minute, unless it is exactly divisible by 10
00092          */
00093         ltc_frame = c->tc.start + c->frames;
00094         if (c->tc.drop)
00095             ltc_frame = avpriv_framenum_to_drop_timecode(ltc_frame);
00096         timecode = avpriv_framenum_to_smpte_timecode(ltc_frame, c->sys->ltc_divisor,
00097                                                      c->tc.drop);
00098         timecode |= 1<<23 | 1<<15 | 1<<7 | 1<<6; // biphase and binary group flags
00099         AV_WB32(buf + 1, timecode);
00100         break;
00101     case dv_audio_source:  /* AAUX source pack */
00102         va_start(ap, buf);
00103         buf[1] = (1 << 7) | /* locked mode -- SMPTE only supports locked mode */
00104                  (1 << 6) | /* reserved -- always 1 */
00105                  (dv_audio_frame_size(c->sys, c->frames) -
00106                   c->sys->audio_min_samples[0]);
00107                             /* # of samples      */
00108         buf[2] = (0 << 7) | /* multi-stereo      */
00109                  (0 << 5) | /* #of audio channels per block: 0 -- 1 channel */
00110                  (0 << 4) | /* pair bit: 0 -- one pair of channels */
00111                  !!va_arg(ap, int); /* audio mode        */
00112         buf[3] = (1 << 7) | /* res               */
00113                  (1 << 6) | /* multi-language flag */
00114                  (c->sys->dsf << 5) | /*  system: 60fields/50fields */
00115                  (c->sys->n_difchan & 2); /* definition: 0 -- 25Mbps, 2 -- 50Mbps */
00116         buf[4] = (1 << 7) | /* emphasis: 1 -- off */
00117                  (0 << 6) | /* emphasis time constant: 0 -- reserved */
00118                  (0 << 3) | /* frequency: 0 -- 48kHz, 1 -- 44,1kHz, 2 -- 32kHz */
00119                   0;        /* quantization: 0 -- 16bit linear, 1 -- 12bit nonlinear */
00120         va_end(ap);
00121         break;
00122     case dv_audio_control:
00123         buf[1] = (0 << 6) | /* copy protection: 0 -- unrestricted */
00124                  (1 << 4) | /* input source: 1 -- digital input */
00125                  (3 << 2) | /* compression: 3 -- no information */
00126                   0;        /* misc. info/SMPTE emphasis off */
00127         buf[2] = (1 << 7) | /* recording start point: 1 -- no */
00128                  (1 << 6) | /* recording end point: 1 -- no */
00129                  (1 << 3) | /* recording mode: 1 -- original */
00130                   7;
00131         buf[3] = (1 << 7) | /* direction: 1 -- forward */
00132                  (c->sys->pix_fmt == PIX_FMT_YUV420P ? 0x20 : /* speed */
00133                                                        c->sys->ltc_divisor * 4);
00134         buf[4] = (1 << 7) | /* reserved -- always 1 */
00135                   0x7f;     /* genre category */
00136         break;
00137     case dv_audio_recdate:
00138     case dv_video_recdate:  /* VAUX recording date */
00139         ct = c->start_time + av_rescale_rnd(c->frames, c->sys->time_base.num,
00140                                             c->sys->time_base.den, AV_ROUND_DOWN);
00141         brktimegm(ct, &tc);
00142         buf[1] = 0xff; /* ds, tm, tens of time zone, units of time zone */
00143                        /* 0xff is very likely to be "unknown" */
00144         buf[2] = (3 << 6) | /* reserved -- always 1 */
00145                  ((tc.tm_mday / 10) << 4) | /* Tens of day */
00146                  (tc.tm_mday % 10);         /* Units of day */
00147         buf[3] = /* we set high 4 bits to 0, shouldn't we set them to week? */
00148                  ((tc.tm_mon / 10) << 4) |    /* Tens of month */
00149                  (tc.tm_mon  % 10);           /* Units of month */
00150         buf[4] = (((tc.tm_year % 100) / 10) << 4) | /* Tens of year */
00151                  (tc.tm_year % 10);                 /* Units of year */
00152         break;
00153     case dv_audio_rectime:  /* AAUX recording time */
00154     case dv_video_rectime:  /* VAUX recording time */
00155         ct = c->start_time + av_rescale_rnd(c->frames, c->sys->time_base.num,
00156                                                        c->sys->time_base.den, AV_ROUND_DOWN);
00157         brktimegm(ct, &tc);
00158         buf[1] = (3 << 6) | /* reserved -- always 1 */
00159                  0x3f; /* tens of frame, units of frame: 0x3f - "unknown" ? */
00160         buf[2] = (1 << 7) | /* reserved -- always 1 */
00161                  ((tc.tm_sec / 10) << 4) | /* Tens of seconds */
00162                  (tc.tm_sec % 10);         /* Units of seconds */
00163         buf[3] = (1 << 7) | /* reserved -- always 1 */
00164                  ((tc.tm_min / 10) << 4) | /* Tens of minutes */
00165                  (tc.tm_min % 10);         /* Units of minutes */
00166         buf[4] = (3 << 6) | /* reserved -- always 1 */
00167                  ((tc.tm_hour / 10) << 4) | /* Tens of hours */
00168                  (tc.tm_hour % 10);         /* Units of hours */
00169         break;
00170     default:
00171         buf[1] = buf[2] = buf[3] = buf[4] = 0xff;
00172     }
00173     return 5;
00174 }
00175 
00176 static void dv_inject_audio(DVMuxContext *c, int channel, uint8_t* frame_ptr)
00177 {
00178     int i, j, d, of, size;
00179     size = 4 * dv_audio_frame_size(c->sys, c->frames);
00180     frame_ptr += channel * c->sys->difseg_size * 150 * 80;
00181     for (i = 0; i < c->sys->difseg_size; i++) {
00182         frame_ptr += 6 * 80; /* skip DIF segment header */
00183         for (j = 0; j < 9; j++) {
00184             dv_write_pack(dv_aaux_packs_dist[i][j], c, &frame_ptr[3], i >= c->sys->difseg_size/2);
00185             for (d = 8; d < 80; d+=2) {
00186                 of = c->sys->audio_shuffle[i][j] + (d - 8)/2 * c->sys->audio_stride;
00187                 if (of*2 >= size)
00188                     continue;
00189 
00190                 frame_ptr[d]   = *av_fifo_peek2(c->audio_data[channel], of*2+1); // FIXME: maybe we have to admit
00191                 frame_ptr[d+1] = *av_fifo_peek2(c->audio_data[channel], of*2);   //        that DV is a big-endian PCM
00192             }
00193             frame_ptr += 16 * 80; /* 15 Video DIFs + 1 Audio DIF */
00194         }
00195     }
00196 }
00197 
00198 static void dv_inject_metadata(DVMuxContext *c, uint8_t* frame)
00199 {
00200     int j, k;
00201     uint8_t* buf;
00202 
00203     for (buf = frame; buf < frame + c->sys->frame_size; buf += 150 * 80) {
00204         /* DV subcode: 2nd and 3d DIFs */
00205         for (j = 80; j < 80 * 3; j += 80) {
00206             for (k = 6; k < 6 * 8; k += 8)
00207                 dv_write_pack(dv_timecode, c, &buf[j+k]);
00208 
00209             if (((long)(buf-frame)/(c->sys->frame_size/(c->sys->difseg_size*c->sys->n_difchan))%c->sys->difseg_size) > 5) { /* FIXME: is this really needed ? */
00210                 dv_write_pack(dv_video_recdate, c, &buf[j+14]);
00211                 dv_write_pack(dv_video_rectime, c, &buf[j+22]);
00212                 dv_write_pack(dv_video_recdate, c, &buf[j+38]);
00213                 dv_write_pack(dv_video_rectime, c, &buf[j+46]);
00214             }
00215         }
00216 
00217         /* DV VAUX: 4th, 5th and 6th 3DIFs */
00218         for (j = 80*3 + 3; j < 80*6; j += 80) {
00219             dv_write_pack(dv_video_recdate, c, &buf[j+5*2]);
00220             dv_write_pack(dv_video_rectime, c, &buf[j+5*3]);
00221             dv_write_pack(dv_video_recdate, c, &buf[j+5*11]);
00222             dv_write_pack(dv_video_rectime, c, &buf[j+5*12]);
00223         }
00224     }
00225 }
00226 
00227 /*
00228  * The following 3 functions constitute our interface to the world
00229  */
00230 
00231 static int dv_assemble_frame(DVMuxContext *c, AVStream* st,
00232                              uint8_t* data, int data_size, uint8_t** frame)
00233 {
00234     int i, reqasize;
00235 
00236     *frame = &c->frame_buf[0];
00237     reqasize = 4 * dv_audio_frame_size(c->sys, c->frames);
00238 
00239     switch (st->codec->codec_type) {
00240     case AVMEDIA_TYPE_VIDEO:
00241         /* FIXME: we have to have more sensible approach than this one */
00242         if (c->has_video)
00243             av_log(st->codec, AV_LOG_ERROR, "Can't process DV frame #%d. Insufficient audio data or severe sync problem.\n", c->frames);
00244 
00245         memcpy(*frame, data, c->sys->frame_size);
00246         c->has_video = 1;
00247         break;
00248     case AVMEDIA_TYPE_AUDIO:
00249         for (i = 0; i < c->n_ast && st != c->ast[i]; i++);
00250 
00251           /* FIXME: we have to have more sensible approach than this one */
00252         if (av_fifo_size(c->audio_data[i]) + data_size >= 100*AVCODEC_MAX_AUDIO_FRAME_SIZE)
00253             av_log(st->codec, AV_LOG_ERROR, "Can't process DV frame #%d. Insufficient video data or severe sync problem.\n", c->frames);
00254         av_fifo_generic_write(c->audio_data[i], data, data_size, NULL);
00255 
00256         /* Let us see if we've got enough audio for one DV frame. */
00257         c->has_audio |= ((reqasize <= av_fifo_size(c->audio_data[i])) << i);
00258 
00259         break;
00260     default:
00261         break;
00262     }
00263 
00264     /* Let us see if we have enough data to construct one DV frame. */
00265     if (c->has_video == 1 && c->has_audio + 1 == 1 << c->n_ast) {
00266         dv_inject_metadata(c, *frame);
00267         c->has_audio = 0;
00268         for (i=0; i < c->n_ast; i++) {
00269             dv_inject_audio(c, i, *frame);
00270             av_fifo_drain(c->audio_data[i], reqasize);
00271             c->has_audio |= ((reqasize <= av_fifo_size(c->audio_data[i])) << i);
00272         }
00273 
00274         c->has_video = 0;
00275 
00276         c->frames++;
00277 
00278         return c->sys->frame_size;
00279     }
00280 
00281     return 0;
00282 }
00283 
00284 static DVMuxContext* dv_init_mux(AVFormatContext* s)
00285 {
00286     DVMuxContext *c = s->priv_data;
00287     AVStream *vst = NULL;
00288     AVDictionaryEntry *t;
00289     int i;
00290 
00291     /* we support at most 1 video and 2 audio streams */
00292     if (s->nb_streams > 3)
00293         return NULL;
00294 
00295     c->n_ast  = 0;
00296     c->ast[0] = c->ast[1] = NULL;
00297 
00298     /* We have to sort out where audio and where video stream is */
00299     for (i=0; i<s->nb_streams; i++) {
00300         switch (s->streams[i]->codec->codec_type) {
00301         case AVMEDIA_TYPE_VIDEO:
00302             if (vst) return NULL;
00303             vst = s->streams[i];
00304             break;
00305         case AVMEDIA_TYPE_AUDIO:
00306             if (c->n_ast > 1) return NULL;
00307             c->ast[c->n_ast++] = s->streams[i];
00308             break;
00309         default:
00310             goto bail_out;
00311         }
00312     }
00313 
00314     /* Some checks -- DV format is very picky about its incoming streams */
00315     if (!vst || vst->codec->codec_id != CODEC_ID_DVVIDEO)
00316         goto bail_out;
00317     for (i=0; i<c->n_ast; i++) {
00318         if (c->ast[i] && (c->ast[i]->codec->codec_id    != CODEC_ID_PCM_S16LE ||
00319                           c->ast[i]->codec->sample_rate != 48000 ||
00320                           c->ast[i]->codec->channels    != 2))
00321             goto bail_out;
00322     }
00323     c->sys = avpriv_dv_codec_profile(vst->codec);
00324     if (!c->sys)
00325         goto bail_out;
00326 
00327     if ((c->n_ast > 1) && (c->sys->n_difchan < 2)) {
00328         /* only 1 stereo pair is allowed in 25Mbps mode */
00329         goto bail_out;
00330     }
00331 
00332     /* Ok, everything seems to be in working order */
00333     c->frames     = 0;
00334     c->has_audio  = 0;
00335     c->has_video  = 0;
00336 #if FF_API_TIMESTAMP
00337     if (s->timestamp)
00338         c->start_time = s->timestamp;
00339     else
00340 #endif
00341     if (t = av_dict_get(s->metadata, "creation_time", NULL, 0))
00342         c->start_time = ff_iso8601_to_unix_time(t->value);
00343 
00344     for (i=0; i < c->n_ast; i++) {
00345         if (c->ast[i] && !(c->audio_data[i]=av_fifo_alloc(100*AVCODEC_MAX_AUDIO_FRAME_SIZE))) {
00346             while (i > 0) {
00347                 i--;
00348                 av_fifo_free(c->audio_data[i]);
00349             }
00350             goto bail_out;
00351         }
00352     }
00353 
00354     return c;
00355 
00356 bail_out:
00357     return NULL;
00358 }
00359 
00360 static void dv_delete_mux(DVMuxContext *c)
00361 {
00362     int i;
00363     for (i=0; i < c->n_ast; i++)
00364         av_fifo_free(c->audio_data[i]);
00365 }
00366 
00367 static int dv_write_header(AVFormatContext *s)
00368 {
00369     DVMuxContext *dvc = s->priv_data;
00370 
00371     if (!dv_init_mux(s)) {
00372         av_log(s, AV_LOG_ERROR, "Can't initialize DV format!\n"
00373                     "Make sure that you supply exactly two streams:\n"
00374                     "     video: 25fps or 29.97fps, audio: 2ch/48kHz/PCM\n"
00375                     "     (50Mbps allows an optional second audio stream)\n");
00376         return -1;
00377     }
00378     if (dvc->tc.str) {
00379         dvc->tc.rate.num = dvc->sys->time_base.den;
00380         dvc->tc.rate.den = dvc->sys->time_base.num;
00381         if (avpriv_init_smpte_timecode(s, &dvc->tc) < 0)
00382             return -1;
00383     }
00384     return 0;
00385 }
00386 
00387 static int dv_write_packet(struct AVFormatContext *s, AVPacket *pkt)
00388 {
00389     uint8_t* frame;
00390     int fsize;
00391 
00392     fsize = dv_assemble_frame(s->priv_data, s->streams[pkt->stream_index],
00393                               pkt->data, pkt->size, &frame);
00394     if (fsize > 0) {
00395         avio_write(s->pb, frame, fsize);
00396         avio_flush(s->pb);
00397     }
00398     return 0;
00399 }
00400 
00401 /*
00402  * We might end up with some extra A/V data without matching counterpart.
00403  * E.g. video data without enough audio to write the complete frame.
00404  * Currently we simply drop the last frame. I don't know whether this
00405  * is the best strategy of all
00406  */
00407 static int dv_write_trailer(struct AVFormatContext *s)
00408 {
00409     dv_delete_mux(s->priv_data);
00410     return 0;
00411 }
00412 
00413 static const AVClass class = {
00414     .class_name = "dv",
00415     .item_name  = av_default_item_name,
00416     .version    = LIBAVUTIL_VERSION_INT,
00417     .option     = (const AVOption[]){
00418         {TIMECODE_OPT(DVMuxContext, AV_OPT_FLAG_ENCODING_PARAM)},
00419         {NULL},
00420     },
00421 };
00422 
00423 AVOutputFormat ff_dv_muxer = {
00424     .name              = "dv",
00425     .long_name         = NULL_IF_CONFIG_SMALL("DV video format"),
00426     .extensions        = "dv",
00427     .priv_data_size    = sizeof(DVMuxContext),
00428     .audio_codec       = CODEC_ID_PCM_S16LE,
00429     .video_codec       = CODEC_ID_DVVIDEO,
00430     .write_header      = dv_write_header,
00431     .write_packet      = dv_write_packet,
00432     .write_trailer     = dv_write_trailer,
00433     .priv_class        = &class,
00434 };