dv.c

FFmpeg is an audio/video conversion tool. It includes libavcodec, the leading open source codec libr

/* 
 * General DV muxer/demuxer 
 * Copyright (c) 2003 Roman Shaposhnick
 *
 * Many thanks to Dan Dennedy <[e-mail]> for providing wealth
 * of DV technical info.
 *
 * Raw DV format
 * Copyright (c) 2002 Fabrice Bellard.
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2 of the License, or (at your option) any later version.
 *
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 */
#include <time.h>
#include "avformat.h"
#include "dvdata.h"
#include "dv.h"

struct DVDemuxContext {
    AVFormatContext* fctx;
    AVStream*        vst;
    AVStream*        ast[2];       
    AVPacket         audio_pkt[2];
    int              ach;
    int              frames;
    uint64_t         abytes;
};

struct DVMuxContext {
    const DVprofile*  sys;    /* Current DV profile. E.g.: 525/60, 625/50 */
    uint8_t     frame_buf[144000]; /* frame under contruction */
    FifoBuffer  audio_data;   /* Fifo for storing excessive amounts of PCM */
    int         frames;       /* Number of a current frame */
    time_t      start_time;   /* Start time of recording */
    uint8_t     aspect;       /* Aspect ID 0 - 4:3, 7 - 16:9 */
    int         has_audio;    /* frame under contruction has audio */
    int         has_video;    /* frame under contruction has video */
};

enum dv_section_type {
     dv_sect_header  = 0x1f,
     dv_sect_subcode = 0x3f,
     dv_sect_vaux    = 0x56,
     dv_sect_audio   = 0x76,
     dv_sect_video   = 0x96,
};

enum dv_pack_type {
     dv_header525     = 0x3f, /* see dv_write_pack for important details on */ 
     dv_header625     = 0xbf, /* these two packs */
     dv_timecode      = 0x13,
     dv_audio_source  = 0x50,
     dv_audio_control = 0x51,
     dv_audio_recdate = 0x52,
     dv_audio_rectime = 0x53,
     dv_video_source  = 0x60,
     dv_video_control = 0x61,
     dv_viedo_recdate = 0x62,
     dv_video_rectime = 0x63,
     dv_unknown_pack  = 0xff,
};



/*
 * The reason why the following three big ugly looking tables are
 * here is my lack of DV spec IEC 61834. The tables were basically 
 * constructed to make code that places packs in SSYB, VAUX and 
 * AAUX blocks very simple and table-driven. They conform to the
 * SMPTE 314M and the output of my personal DV camcorder, neither
 * of which is sufficient for a reliable DV stream producing. Thus
 * while code is still in development I'll be gathering input from
 * people with different DV equipment and modifying the tables to
 * accommodate all the quirks. Later on, if possible, some of them
 * will be folded into smaller tables and/or switch-if logic. For 
 * now, my only excuse is -- they don't eat up that much of a space.
 */

static const int dv_ssyb_packs_dist[12][6] = {
    { 0x13, 0x13, 0x13, 0x13, 0x13, 0x13 },
    { 0x13, 0x13, 0x13, 0x13, 0x13, 0x13 },
    { 0x13, 0x13, 0x13, 0x13, 0x13, 0x13 },
    { 0x13, 0x13, 0x13, 0x13, 0x13, 0x13 },
    { 0x13, 0x13, 0x13, 0x13, 0x13, 0x13 },
    { 0x13, 0x13, 0x13, 0x13, 0x13, 0x13 },
    { 0x13, 0x62, 0x63, 0x13, 0x62, 0x63 },
    { 0x13, 0x62, 0x63, 0x13, 0x62, 0x63 },
    { 0x13, 0x62, 0x63, 0x13, 0x62, 0x63 },
    { 0x13, 0x62, 0x63, 0x13, 0x62, 0x63 },
    { 0x13, 0x62, 0x63, 0x13, 0x62, 0x63 },
    { 0x13, 0x62, 0x63, 0x13, 0x62, 0x63 },
};

static const int dv_vaux_packs_dist[12][15] = {
    { 0x60, 0x61, 0x62, 0x63, 0xff, 0xff, 0xff, 0xff, 0xff, 
      0x60, 0x61, 0x62, 0x63, 0xff, 0xff },
    { 0x60, 0x61, 0x62, 0x63, 0xff, 0xff, 0xff, 0xff, 0xff, 
      0x60, 0x61, 0x62, 0x63, 0xff, 0xff },
    { 0x60, 0x61, 0x62, 0x63, 0xff, 0xff, 0xff, 0xff, 0xff, 
      0x60, 0x61, 0x62, 0x63, 0xff, 0xff },
    { 0x60, 0x61, 0x62, 0x63, 0xff, 0xff, 0xff, 0xff, 0xff, 
      0x60, 0x61, 0x62, 0x63, 0xff, 0xff },
    { 0x60, 0x61, 0x62, 0x63, 0xff, 0xff, 0xff, 0xff, 0xff, 
      0x60, 0x61, 0x62, 0x63, 0xff, 0xff },
    { 0x60, 0x61, 0x62, 0x63, 0xff, 0xff, 0xff, 0xff, 0xff, 
      0x60, 0x61, 0x62, 0x63, 0xff, 0xff },
    { 0x60, 0x61, 0x62, 0x63, 0xff, 0xff, 0xff, 0xff, 0xff, 
      0x60, 0x61, 0x62, 0x63, 0xff, 0xff },
    { 0x60, 0x61, 0x62, 0x63, 0xff, 0xff, 0xff, 0xff, 0xff, 
      0x60, 0x61, 0x62, 0x63, 0xff, 0xff },
    { 0x60, 0x61, 0x62, 0x63, 0xff, 0xff, 0xff, 0xff, 0xff, 
      0x60, 0x61, 0x62, 0x63, 0xff, 0xff },
    { 0x60, 0x61, 0x62, 0x63, 0xff, 0xff, 0xff, 0xff, 0xff, 
      0x60, 0x61, 0x62, 0x63, 0xff, 0xff },
    { 0x60, 0x61, 0x62, 0x63, 0xff, 0xff, 0xff, 0xff, 0xff, 
      0x60, 0x61, 0x62, 0x63, 0xff, 0xff },
    { 0x60, 0x61, 0x62, 0x63, 0xff, 0xff, 0xff, 0xff, 0xff, 
      0x60, 0x61, 0x62, 0x63, 0xff, 0xff },
};

static const int dv_aaux_packs_dist[12][9] = {
    { 0xff, 0xff, 0xff, 0x50, 0x51, 0x52, 0x53, 0xff, 0xff },
    { 0x50, 0x51, 0x52, 0x53, 0xff, 0xff, 0xff, 0xff, 0xff },
    { 0xff, 0xff, 0xff, 0x50, 0x51, 0x52, 0x53, 0xff, 0xff },
    { 0x50, 0x51, 0x52, 0x53, 0xff, 0xff, 0xff, 0xff, 0xff },
    { 0xff, 0xff, 0xff, 0x50, 0x51, 0x52, 0x53, 0xff, 0xff },
    { 0x50, 0x51, 0x52, 0x53, 0xff, 0xff, 0xff, 0xff, 0xff },
    { 0xff, 0xff, 0xff, 0x50, 0x51, 0x52, 0x53, 0xff, 0xff },
    { 0x50, 0x51, 0x52, 0x53, 0xff, 0xff, 0xff, 0xff, 0xff },
    { 0xff, 0xff, 0xff, 0x50, 0x51, 0x52, 0x53, 0xff, 0xff },
    { 0x50, 0x51, 0x52, 0x53, 0xff, 0xff, 0xff, 0xff, 0xff },
    { 0xff, 0xff, 0xff, 0x50, 0x51, 0x52, 0x53, 0xff, 0xff },
    { 0x50, 0x51, 0x52, 0x53, 0xff, 0xff, 0xff, 0xff, 0xff },
};

static inline uint16_t dv_audio_12to16(uint16_t sample)
{
    uint16_t shift, result;
    
    sample = (sample < 0x800) ? sample : sample | 0xf000;
    shift = (sample & 0xf00) >> 8;

    if (shift < 0x2 || shift > 0xd) {
	result = sample;
    } else if (shift < 0x8) {
        shift--;
	result = (sample - (256 * shift)) << shift;
    } else {
	shift = 0xe - shift;
	result = ((sample + ((256 * shift) + 1)) << shift) - 1;
    }

    return result;
}

static int dv_audio_frame_size(const DVprofile* sys, int frame)
{
    return sys->audio_samples_dist[frame % (sizeof(sys->audio_samples_dist)/
		                            sizeof(sys->audio_samples_dist[0]))];
}

static int dv_write_pack(enum dv_pack_type pack_id, DVMuxContext *c, uint8_t* buf)
{
    struct tm tc;
    time_t ct;
    int ltc_frame;

    buf[0] = (uint8_t)pack_id;
    switch (pack_id) {
    case dv_header525: /* I can't imagine why these two weren't defined as real */
    case dv_header625: /* packs in SMPTE314M -- they definitely look like ones */
          buf[1] = 0xf8 |               /* reserved -- always 1 */
	           (0 & 0x07);          /* APT: Track application ID */
          buf[2] = (0 << 7)    | /* TF1: audio data is 0 - valid; 1 - invalid */
	           (0x0f << 3) | /* reserved -- always 1 */
		   (0 & 0x07);   /* AP1: Audio application ID */
          buf[3] = (0 << 7)    | /* TF2: video data is 0 - valid; 1 - invalid */  
	           (0x0f << 3) | /* reserved -- always 1 */
		   (0 & 0x07);   /* AP2: Video application ID */
          buf[4] = (0 << 7)    | /* TF3: subcode(SSYB) is 0 - valid; 1 - invalid */ 
	           (0x0f << 3) | /* reserved -- always 1 */
		   (0 & 0x07);   /* AP3: Subcode application ID */
	  break;
    case dv_timecode:
          ct = (time_t)(c->frames / ((float)c->sys->frame_rate / 
                                     (float)c->sys->frame_rate_base));
          localtime_r(&ct, &tc);
          /* 
           * LTC drop-frame frame counter drops two frames (0 and 1) every 
           * minute, unless it is exactly divisible by 10
           */
          ltc_frame = (c->frames + 2*ct/60 - 2*ct/600) % c->sys->ltc_divisor;
	  buf[1] = (0 << 7) | /* Color fame: 0 - unsync; 1 - sync mode */
		   (1 << 6) | /* Drop frame timecode: 0 - nondrop; 1 - drop */
		   ((ltc_frame / 10) << 4) | /* Tens of frames */
		   (ltc_frame % 10);         /* Units of frames */
	  buf[2] = (1 << 7) | /* Biphase mark polarity correction: 0 - even; 1 - odd */
		   ((tc.tm_sec / 10) << 4) | /* Tens of seconds */
		   (tc.tm_sec % 10);         /* Units of seconds */
	  buf[3] = (1 << 7) | /* Binary group flag BGF0 */
		   ((tc.tm_min / 10) << 4) | /* Tens of minutes */
		   (tc.tm_min % 10);         /* Units of minutes */
	  buf[4] = (1 << 7) | /* Binary group flag BGF2 */
		   (1 << 6) | /* Binary group flag BGF1 */
	           ((tc.tm_hour / 10) << 4) | /* Tens of hours */
		   (tc.tm_hour % 10);         /* Units of hours */
          break;
    case dv_audio_source:  /* AAUX source pack */
          buf[1] = (0 << 7) | /* locked mode       */
                   (1 << 6) | /* reserved -- always 1 */
	           (dv_audio_frame_size(c->sys, c->frames) -
		    c->sys->audio_min_samples[0]);
	                      /* # of samples      */
          buf[2] = (0 << 7) | /* multi-stereo      */
                   (0 << 5) | /* #of audio channels per block: 0 -- 1 channel */
                   (0 << 4) | /* pair bit: 0 -- one pair of channels */
	            0;        /* audio mode        */
          buf[3] = (1 << 7) | /* res               */
                   (1 << 6) | /* multi-language flag */
	           (c->sys->dsf << 5) | /*  system: 60fields/50fields */
	            0;        /* definition: 0 -- SD (525/625) */
          buf[4] = (1 << 7) | /* emphasis: 1 -- off */
                   (0 << 6) | /* emphasis time constant: 0 -- reserved */
	           (0 << 3) | /* frequency: 0 -- 48Khz, 1 -- 44,1Khz, 2 -- 32Khz */
                    0;        /* quantization: 0 -- 16bit linear, 1 -- 12bit nonlinear */			    
          break;
    case dv_audio_control:
          buf[1] = (0 << 6) | /* copy protection: 0 -- unrestricted */
                   (1 << 4) | /* input source: 1 -- digital input */
	           (3 << 2) | /* compression: 3 -- no information */
	            0;        /* misc. info/SMPTE emphasis off */
          buf[2] = (1 << 7) | /* recording start point: 1 -- no */
                   (1 << 6) | /* recording end point: 1 -- no */
	           (1 << 3) | /* recording mode: 1 -- original */
	            7;         
          buf[3] = (1 << 7) | /* direction: 1 -- forward */
                    0x20;     /* speed */
          buf[4] = (1 << 7) | /* reserved -- always 1 */
                    0x7f;     /* genre category */
	  break;
    case dv_audio_recdate:
    case dv_viedo_recdate:  /* VAUX recording date */
          ct = c->start_time + (time_t)(c->frames / 
	       ((float)c->sys->frame_rate / (float)c->sys->frame_rate_base));
          localtime_r(&ct, &tc);
	  buf[1] = 0xff; /* ds, tm, tens of time zone, units of time zone */
	                 /* 0xff is very likely to be "unknown" */
	  buf[2] = (3 << 6) | /* reserved -- always 1 */
		   ((tc.tm_mday / 10) << 4) | /* Tens of day */
		   (tc.tm_mday % 10);         /* Units of day */
	  buf[3] = /* we set high 4 bits to 0, shouldn't we set them to week? */
		   (tc.tm_mon % 10);         /* Units of month */
	  buf[4] = (((tc.tm_year % 100) / 10) << 4) | /* Tens of year */
		   (tc.tm_year % 10);                 /* Units of year */
          break;
    case dv_audio_rectime:  /* AAUX recording time */
    case dv_video_rectime:  /* VAUX recording time */
          ct = c->start_time + (time_t)(c->frames / 
	       ((float)c->sys->frame_rate / (float)c->sys->frame_rate_base));
          localtime_r(&ct, &tc);
	  buf[1] = (3 << 6) | /* reserved -- always 1 */
		   0x3f; /* tens of frame, units of frame: 0x3f - "unknown" ? */
	  buf[2] = (1 << 7) | /* reserved -- always 1 */ 
		   ((tc.tm_sec / 10) << 4) | /* Tens of seconds */
		   (tc.tm_sec % 10);         /* Units of seconds */
	  buf[3] = (1 << 7) | /* reserved -- always 1 */
		   ((tc.tm_min / 10) << 4) | /* Tens of minutes */
		   (tc.tm_min % 10);         /* Units of minutes */
	  buf[4] = (3 << 6) | /* reserved -- always 1 */ 
	           ((tc.tm_hour / 10) << 4) | /* Tens of hours */
		   (tc.tm_hour % 10);         /* Units of hours */
	  break;
    case dv_video_source:
	  buf[1] = 0xff; /* reserved -- always 1 */
	  buf[2] = (1 << 7) | /* B/W: 0 - b/w, 1 - color */
		   (1 << 6) | /* following CLF is valid - 0, invalid - 1 */
		   (3 << 4) | /* CLF: color frames id (see ITU-R BT.470-4) */
		   0xf; /* reserved -- always 1 */
	  buf[3] = (3 << 6) | /* reserved -- always 1 */
		   (c->sys->dsf << 5) | /*  system: 60fields/50fields */
		   0; /* signal type video compression */
	  buf[4] = 0xff; /* VISC: 0xff -- no information */
          break;
    case dv_video_control:
	  buf[1] = (0 << 6) | /* Copy generation management (CGMS) 0 -- free */
		   0x3f; /* reserved -- always 1 */
	  buf[2] = 0xc8 | /* reserved -- always b11001xxx */
		   c->aspect;
	  buf[3] = (1 << 7) | /* Frame/field flag 1 -- frame, 0 -- field */
		   (1 << 6) | /* First/second field flag 0 -- field 2, 1 -- field 1 */
		   (1 << 5) | /* Frame change flag 0 -- same picture as before, 1 -- different */
		   (1 << 4) | /* 1 - interlaced, 0 - noninterlaced */
		   0xc; /* reserved -- always b1100 */
	  buf[4] = 0xff; /* reserved -- always 1 */
          break;
    default:
          buf[1] = buf[2] = buf[3] = buf[4] = 0xff;
    }
    return 5;
}

static inline int dv_write_dif_id(enum dv_section_type t, uint8_t seq_num, 
                                  uint8_t dif_num, uint8_t* buf)
{
    buf[0] = (uint8_t)t;    /* Section type */