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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 #include "avformat.h"
00033 #include "libavcodec/dvdata.h"
00034 #include "dv.h"
00035 #include "libavutil/fifo.h"
00036 
00037 struct DVMuxContext {
00038     const DVprofile*  sys;           /* current DV profile, e.g.: 525/60, 625/50 */
00039     int               n_ast;         /* number of stereo audio streams (up to 2) */
00040     AVStream         *ast[2];        /* stereo audio streams */
00041     AVFifoBuffer      audio_data[2]; /* FIFO for storing excessive amounts of PCM */
00042     int               frames;        /* current frame number */
00043     time_t            start_time;    /* recording start time */
00044     int               has_audio;     /* frame under contruction has audio */
00045     int               has_video;     /* frame under contruction has video */
00046     uint8_t           frame_buf[DV_MAX_FRAME_SIZE]; /* frame under contruction */
00047 };
00048 
00049 static const int dv_aaux_packs_dist[12][9] = {
00050     { 0xff, 0xff, 0xff, 0x50, 0x51, 0x52, 0x53, 0xff, 0xff },
00051     { 0x50, 0x51, 0x52, 0x53, 0xff, 0xff, 0xff, 0xff, 0xff },
00052     { 0xff, 0xff, 0xff, 0x50, 0x51, 0x52, 0x53, 0xff, 0xff },
00053     { 0x50, 0x51, 0x52, 0x53, 0xff, 0xff, 0xff, 0xff, 0xff },
00054     { 0xff, 0xff, 0xff, 0x50, 0x51, 0x52, 0x53, 0xff, 0xff },
00055     { 0x50, 0x51, 0x52, 0x53, 0xff, 0xff, 0xff, 0xff, 0xff },
00056     { 0xff, 0xff, 0xff, 0x50, 0x51, 0x52, 0x53, 0xff, 0xff },
00057     { 0x50, 0x51, 0x52, 0x53, 0xff, 0xff, 0xff, 0xff, 0xff },
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 };
00063 
00064 static int dv_audio_frame_size(const DVprofile* sys, int frame)
00065 {
00066     return sys->audio_samples_dist[frame % (sizeof(sys->audio_samples_dist) /
00067                                             sizeof(sys->audio_samples_dist[0]))];
00068 }
00069 
00070 static int dv_write_pack(enum dv_pack_type pack_id, DVMuxContext *c, uint8_t* buf, ...)
00071 {
00072     struct tm tc;
00073     time_t ct;
00074     int ltc_frame;
00075     va_list ap;
00076 
00077     buf[0] = (uint8_t)pack_id;
00078     switch (pack_id) {
00079     case dv_timecode:
00080         ct = (time_t)av_rescale_rnd(c->frames, c->sys->time_base.num,
00081                                     c->sys->time_base.den, AV_ROUND_DOWN);
00082         brktimegm(ct, &tc);
00083         /*
00084          * LTC drop-frame frame counter drops two frames (0 and 1) every
00085          * minute, unless it is exactly divisible by 10
00086          */
00087         ltc_frame = (c->frames + 2 * ct / 60 - 2 * ct / 600) % c->sys->ltc_divisor;
00088         buf[1] = (0                 << 7) | /* color frame: 0 - unsync; 1 - sync mode */
00089                  (1                 << 6) | /* drop frame timecode: 0 - nondrop; 1 - drop */
00090                  ((ltc_frame / 10)  << 4) | /* tens of frames */
00091                  (ltc_frame % 10);          /* units of frames */
00092         buf[2] = (1                 << 7) | /* biphase mark polarity correction: 0 - even; 1 - odd */
00093                  ((tc.tm_sec / 10)  << 4) | /* tens of seconds */
00094                  (tc.tm_sec % 10);          /* units of seconds */
00095         buf[3] = (1                 << 7) | /* binary group flag BGF0 */
00096                  ((tc.tm_min / 10)  << 4) | /* tens of minutes */
00097                  (tc.tm_min % 10);          /* units of minutes */
00098         buf[4] = (1                 << 7) | /* binary group flag BGF2 */
00099                  (1                 << 6) | /* binary group flag BGF1 */
00100                  ((tc.tm_hour / 10) << 4) | /* tens of hours */
00101                  (tc.tm_hour % 10);         /* units of hours */
00102         break;
00103     case dv_audio_source:  /* AAUX source pack */
00104         va_start(ap, buf);
00105         buf[1] = (1 << 7) | /* locked mode -- SMPTE only supports locked mode */
00106                  (1 << 6) | /* reserved -- always 1 */
00107                  (dv_audio_frame_size(c->sys, c->frames) -
00108                   c->sys->audio_min_samples[0]);
00109                             /* # of samples      */
00110         buf[2] = (0 << 7) | /* multi-stereo      */
00111                  (0 << 5) | /* #of audio channels per block: 0 -- 1 channel */
00112                  (0 << 4) | /* pair bit: 0 -- one pair of channels */
00113                  !!va_arg(ap, int); /* audio mode        */
00114         buf[3] = (1 << 7) | /* res               */
00115                  (1 << 6) | /* multi-language flag */
00116                  (c->sys->dsf << 5) | /*  system: 60fields/50fields */
00117                  (c->sys->n_difchan & 2); /* definition: 0 -- 25Mbps, 2 -- 50Mbps */
00118         buf[4] = (1 << 7) | /* emphasis: 1 -- off */
00119                  (0 << 6) | /* emphasis time constant: 0 -- reserved */
00120                  (0 << 3) | /* frequency: 0 -- 48kHz, 1 -- 44,1kHz, 2 -- 32kHz */
00121                   0;        /* quantization: 0 -- 16bit linear, 1 -- 12bit nonlinear */
00122         va_end(ap);
00123         break;
00124     case dv_audio_control:
00125         buf[1] = (0 << 6) | /* copy protection: 0 -- unrestricted */
00126                  (1 << 4) | /* input source: 1 -- digital input */
00127                  (3 << 2) | /* compression: 3 -- no information */
00128                   0;        /* misc. info/SMPTE emphasis off */
00129         buf[2] = (1 << 7) | /* recording start point: 1 -- no */
00130                  (1 << 6) | /* recording end point: 1 -- no */
00131                  (1 << 3) | /* recording mode: 1 -- original */
00132                   7;
00133         buf[3] = (1 << 7) | /* direction: 1 -- forward */
00134                  (c->sys->pix_fmt == PIX_FMT_YUV420P ? 0x20 : /* speed */
00135                                                        c->sys->ltc_divisor * 4);
00136         buf[4] = (1 << 7) | /* reserved -- always 1 */
00137                   0x7f;     /* genre category */
00138         break;
00139     case dv_audio_recdate:
00140     case dv_video_recdate:  /* VAUX recording date */
00141         ct = c->start_time + av_rescale_rnd(c->frames, c->sys->time_base.num,
00142                                             c->sys->time_base.den, AV_ROUND_DOWN);
00143         brktimegm(ct, &tc);
00144         buf[1] = 0xff; /* ds, tm, tens of time zone, units of time zone */
00145                        /* 0xff is very likely to be "unknown" */
00146         buf[2] = (3 << 6) | /* reserved -- always 1 */
00147                  ((tc.tm_mday / 10) << 4) | /* Tens of day */
00148                  (tc.tm_mday % 10);         /* Units of day */
00149         buf[3] = /* we set high 4 bits to 0, shouldn't we set them to week? */
00150                  ((tc.tm_mon / 10) << 4) |    /* Tens of month */
00151                  (tc.tm_mon  % 10);           /* Units of month */
00152         buf[4] = (((tc.tm_year % 100) / 10) << 4) | /* Tens of year */
00153                  (tc.tm_year % 10);                 /* Units of year */
00154         break;
00155     case dv_audio_rectime:  /* AAUX recording time */
00156     case dv_video_rectime:  /* VAUX recording time */
00157         ct = c->start_time + av_rescale_rnd(c->frames, c->sys->time_base.num,
00158                                                        c->sys->time_base.den, AV_ROUND_DOWN);
00159         brktimegm(ct, &tc);
00160         buf[1] = (3 << 6) | /* reserved -- always 1 */
00161                  0x3f; /* tens of frame, units of frame: 0x3f - "unknown" ? */
00162         buf[2] = (1 << 7) | /* reserved -- always 1 */
00163                  ((tc.tm_sec / 10) << 4) | /* Tens of seconds */
00164                  (tc.tm_sec % 10);         /* Units of seconds */
00165         buf[3] = (1 << 7) | /* reserved -- always 1 */
00166                  ((tc.tm_min / 10) << 4) | /* Tens of minutes */
00167                  (tc.tm_min % 10);         /* Units of minutes */
00168         buf[4] = (3 << 6) | /* reserved -- always 1 */
00169                  ((tc.tm_hour / 10) << 4) | /* Tens of hours */
00170                  (tc.tm_hour % 10);         /* Units of hours */
00171         break;
00172     default:
00173         buf[1] = buf[2] = buf[3] = buf[4] = 0xff;
00174     }
00175     return 5;
00176 }
00177 
00178 static void dv_inject_audio(DVMuxContext *c, int channel, uint8_t* frame_ptr)
00179 {
00180     int i, j, d, of, size;
00181     size = 4 * dv_audio_frame_size(c->sys, c->frames);
00182     frame_ptr += channel * c->sys->difseg_size * 150 * 80;
00183     for (i = 0; i < c->sys->difseg_size; i++) {
00184         frame_ptr += 6 * 80; /* skip DIF segment header */
00185         for (j = 0; j < 9; j++) {
00186             dv_write_pack(dv_aaux_packs_dist[i][j], c, &frame_ptr[3], i >= c->sys->difseg_size/2);
00187             for (d = 8; d < 80; d+=2) {
00188                 of = c->sys->audio_shuffle[i][j] + (d - 8)/2 * c->sys->audio_stride;
00189                 if (of*2 >= size)
00190                     continue;
00191 
00192                 frame_ptr[d]   = av_fifo_peek(&c->audio_data[channel], of*2+1); // FIXME: maybe we have to admit
00193                 frame_ptr[d+1] = av_fifo_peek(&c->audio_data[channel], of*2);   //        that DV is a big-endian PCM
00194             }
00195             frame_ptr += 16 * 80; /* 15 Video DIFs + 1 Audio DIF */
00196         }
00197     }
00198 }
00199 
00200 static void dv_inject_metadata(DVMuxContext *c, uint8_t* frame)
00201 {
00202     int j, k;
00203     uint8_t* buf;
00204 
00205     for (buf = frame; buf < frame + c->sys->frame_size; buf += 150 * 80) {
00206         /* DV subcode: 2nd and 3d DIFs */
00207         for (j = 80; j < 80 * 3; j += 80) {
00208             for (k = 6; k < 6 * 8; k += 8)
00209                 dv_write_pack(dv_timecode, c, &buf[j+k]);
00210 
00211             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 ? */
00212                 dv_write_pack(dv_video_recdate, c, &buf[j+14]);
00213                 dv_write_pack(dv_video_rectime, c, &buf[j+22]);
00214                 dv_write_pack(dv_video_recdate, c, &buf[j+38]);
00215                 dv_write_pack(dv_video_rectime, c, &buf[j+46]);
00216             }
00217         }
00218 
00219         /* DV VAUX: 4th, 5th and 6th 3DIFs */
00220         for (j = 80*3 + 3; j < 80*6; j += 80) {
00221             dv_write_pack(dv_video_recdate, c, &buf[j+5*2]);
00222             dv_write_pack(dv_video_rectime, c, &buf[j+5*3]);
00223             dv_write_pack(dv_video_recdate, c, &buf[j+5*11]);
00224             dv_write_pack(dv_video_rectime, c, &buf[j+5*12]);
00225         }
00226     }
00227 }
00228 
00229 /*
00230  * The following 3 functions constitute our interface to the world
00231  */
00232 
00233 int dv_assemble_frame(DVMuxContext *c, AVStream* st,
00234                       uint8_t* data, int data_size, uint8_t** frame)
00235 {
00236     int i, reqasize;
00237 
00238     *frame = &c->frame_buf[0];
00239     reqasize = 4 * dv_audio_frame_size(c->sys, c->frames);
00240 
00241     switch (st->codec->codec_type) {
00242     case CODEC_TYPE_VIDEO:
00243         /* FIXME: we have to have more sensible approach than this one */
00244         if (c->has_video)
00245             av_log(st->codec, AV_LOG_ERROR, "Can't process DV frame #%d. Insufficient audio data or severe sync problem.\n", c->frames);
00246 
00247         memcpy(*frame, data, c->sys->frame_size);
00248         c->has_video = 1;
00249         break;
00250     case CODEC_TYPE_AUDIO:
00251         for (i = 0; i < c->n_ast && st != c->ast[i]; i++);
00252 
00253           /* FIXME: we have to have more sensible approach than this one */
00254         if (av_fifo_size(&c->audio_data[i]) + data_size >= 100*AVCODEC_MAX_AUDIO_FRAME_SIZE)
00255             av_log(st->codec, AV_LOG_ERROR, "Can't process DV frame #%d. Insufficient video data or severe sync problem.\n", c->frames);
00256         av_fifo_generic_write(&c->audio_data[i], data, data_size, NULL);
00257 
00258         /* Let us see if we've got enough audio for one DV frame. */
00259         c->has_audio |= ((reqasize <= av_fifo_size(&c->audio_data[i])) << i);
00260 
00261         break;
00262     default:
00263         break;
00264     }
00265 
00266     /* Let us see if we have enough data to construct one DV frame. */
00267     if (c->has_video == 1 && c->has_audio + 1 == 1 << c->n_ast) {
00268         dv_inject_metadata(c, *frame);
00269         c->has_audio = 0;
00270         for (i=0; i < c->n_ast; i++) {
00271             dv_inject_audio(c, i, *frame);
00272             av_fifo_drain(&c->audio_data[i], reqasize);
00273             c->has_audio |= ((reqasize <= av_fifo_size(&c->audio_data[i])) << i);
00274         }
00275 
00276         c->has_video = 0;
00277 
00278         c->frames++;
00279 
00280         return c->sys->frame_size;
00281     }
00282 
00283     return 0;
00284 }
00285 
00286 DVMuxContext* dv_init_mux(AVFormatContext* s)
00287 {
00288     DVMuxContext *c = s->priv_data;
00289     AVStream *vst = NULL;
00290     int i;
00291 
00292     /* we support at most 1 video and 2 audio streams */
00293     if (s->nb_streams > 3)
00294         return NULL;
00295 
00296     c->n_ast  = 0;
00297     c->ast[0] = c->ast[1] = NULL;
00298 
00299     /* We have to sort out where audio and where video stream is */
00300     for (i=0; i<s->nb_streams; i++) {
00301         switch (s->streams[i]->codec->codec_type) {
00302         case CODEC_TYPE_VIDEO:
00303             if (vst) return NULL;
00304             vst = s->streams[i];
00305             break;
00306         case CODEC_TYPE_AUDIO:
00307             if (c->n_ast > 1) return NULL;
00308             c->ast[c->n_ast++] = s->streams[i];
00309             break;
00310         default:
00311             goto bail_out;
00312         }
00313     }
00314 
00315     /* Some checks -- DV format is very picky about its incoming streams */
00316     if (!vst || vst->codec->codec_id != CODEC_ID_DVVIDEO)
00317         goto bail_out;
00318     for (i=0; i<c->n_ast; i++) {
00319         if (c->ast[i] && (c->ast[i]->codec->codec_id    != CODEC_ID_PCM_S16LE ||
00320                           c->ast[i]->codec->sample_rate != 48000 ||
00321                           c->ast[i]->codec->channels    != 2))
00322             goto bail_out;
00323     }
00324     c->sys = dv_codec_profile(vst->codec);
00325     if (!c->sys)
00326         goto bail_out;
00327 
00328     if ((c->n_ast > 1) && (c->sys->n_difchan < 2)) {
00329         /* only 1 stereo pair is allowed in 25Mbps mode */
00330         goto bail_out;
00331     }
00332 
00333     /* Ok, everything seems to be in working order */
00334     c->frames     = 0;
00335     c->has_audio  = 0;
00336     c->has_video  = 0;
00337     c->start_time = (time_t)s->timestamp;
00338 
00339     for (i=0; i < c->n_ast; i++) {
00340         if (c->ast[i] && av_fifo_init(&c->audio_data[i], 100*AVCODEC_MAX_AUDIO_FRAME_SIZE) < 0) {
00341             while (i > 0) {
00342                 i--;
00343                 av_fifo_free(&c->audio_data[i]);
00344             }
00345             goto bail_out;
00346         }
00347     }
00348 
00349     return c;
00350 
00351 bail_out:
00352     return NULL;
00353 }
00354 
00355 void dv_delete_mux(DVMuxContext *c)
00356 {
00357     int i;
00358     for (i=0; i < c->n_ast; i++)
00359         av_fifo_free(&c->audio_data[i]);
00360 }
00361 
00362 #if CONFIG_DV_MUXER
00363 static int dv_write_header(AVFormatContext *s)
00364 {
00365     if (!dv_init_mux(s)) {
00366         av_log(s, AV_LOG_ERROR, "Can't initialize DV format!\n"
00367                     "Make sure that you supply exactly two streams:\n"
00368                     "     video: 25fps or 29.97fps, audio: 2ch/48kHz/PCM\n"
00369                     "     (50Mbps allows an optional second audio stream)\n");
00370         return -1;
00371     }
00372     return 0;
00373 }
00374 
00375 static int dv_write_packet(struct AVFormatContext *s, AVPacket *pkt)
00376 {
00377     uint8_t* frame;
00378     int fsize;
00379 
00380     fsize = dv_assemble_frame(s->priv_data, s->streams[pkt->stream_index],
00381                               pkt->data, pkt->size, &frame);
00382     if (fsize > 0) {
00383         put_buffer(s->pb, frame, fsize);
00384         put_flush_packet(s->pb);
00385     }
00386     return 0;
00387 }
00388 
00389 /*
00390  * We might end up with some extra A/V data without matching counterpart.
00391  * E.g. video data without enough audio to write the complete frame.
00392  * Currently we simply drop the last frame. I don't know whether this
00393  * is the best strategy of all
00394  */
00395 static int dv_write_trailer(struct AVFormatContext *s)
00396 {
00397     dv_delete_mux(s->priv_data);
00398     return 0;
00399 }
00400 
00401 AVOutputFormat dv_muxer = {
00402     "dv",
00403     NULL_IF_CONFIG_SMALL("DV video format"),
00404     NULL,
00405     "dv",
00406     sizeof(DVMuxContext),
00407     CODEC_ID_PCM_S16LE,
00408     CODEC_ID_DVVIDEO,
00409     dv_write_header,
00410     dv_write_packet,
00411     dv_write_trailer,
00412 };
00413 #endif /* CONFIG_DV_MUXER */

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