| 
							- /* 
 -  * General DV muxer/demuxer 
 -  * Copyright (c) 2003 Roman Shaposhnick
 -  *
 -  * Many thanks to Dan Dennedy <dan@dennedy.org> 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];
 -     uint8_t          audio_buf[2][8192];
 -     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));
 -           brktimegm(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));
 -           brktimegm(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) << 4) |    /* Tens of month */
 - 		   (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));
 - 	  brktimegm(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 */
 -     buf[1] = (seq_num<<4) | /* DIF seq number 0-9 for 525/60; 0-11 for 625/50 */
 - 	     (0 << 3) |     /* FSC: for 50Mb/s 0 - first channel; 1 - second */
 - 	     7;             /* reserved -- always 1 */
 -     buf[2] = dif_num;       /* DIF block number Video: 0-134, Audio: 0-8 */
 -     return 3;
 - }
 - 
 - static inline int dv_write_ssyb_id(uint8_t syb_num, uint8_t fr, uint8_t* buf)
 - {
 -     if (syb_num == 0 || syb_num == 6) {
 - 	buf[0] = (fr<<7) | /* FR ID 1 - first half of each channel; 0 - second */
 - 		 (0<<4)  | /* AP3 (Subcode application ID) */
 - 		 0x0f;     /* reserved -- always 1 */
 -     } 
 -     else if (syb_num == 11) {
 - 	buf[0] = (fr<<7) | /* FR ID 1 - first half of each channel; 0 - second */
 -                  0x7f;     /* reserved -- always 1 */
 -     }
 -     else {
 - 	buf[0] = (fr<<7) | /* FR ID 1 - first half of each channel; 0 - second */
 -                  (0<<4)  | /* APT (Track application ID) */
 - 		 0x0f;     /* reserved -- always 1 */
 -     }
 -     buf[1] = 0xf0 |            /* reserved -- always 1 */
 -              (syb_num & 0x0f); /* SSYB number 0 - 11   */
 -     buf[2] = 0xff;             /* reserved -- always 1 */
 -     return 3;
 - }
 - 
 - static void dv_format_frame(DVMuxContext *c, uint8_t* buf)
 - {
 -     int i, j, k;
 -     
 -     for (i = 0; i < c->sys->difseg_size; i++) {
 -        memset(buf, 0xff, 80 * 6); /* First 6 DIF blocks are for control data */
 -        
 -        /* DV header: 1DIF */
 -        buf += dv_write_dif_id(dv_sect_header, i, 0, buf);
 -        buf += dv_write_pack((c->sys->dsf ? dv_header625 : dv_header525), c, buf);
 -        buf += 72; /* unused bytes */
 - 				   
 -        /* DV subcode: 2DIFs */
 -        for (j = 0; j < 2; j++) {
 -           buf += dv_write_dif_id( dv_sect_subcode, i, j, buf);
 - 	  for (k = 0; k < 6; k++) {
 - 	     buf += dv_write_ssyb_id(k, (i < c->sys->difseg_size/2), buf);
 - 	     buf += dv_write_pack(dv_ssyb_packs_dist[i][k], c, buf);
 - 	  }
 - 	  buf += 29; /* unused bytes */
 -        }
 -        
 -        /* DV VAUX: 3DIFs */
 -        for (j = 0; j < 3; j++) {
 - 	  buf += dv_write_dif_id(dv_sect_vaux, i, j, buf);
 - 	  for (k = 0; k < 15 ; k++)
 - 	     buf += dv_write_pack(dv_vaux_packs_dist[i][k], c, buf);
 - 	  buf += 2; /* unused bytes */
 -        } 
 -        
 -        /* DV Audio/Video: 135 Video DIFs + 9 Audio DIFs */
 -        for (j = 0; j < 135; j++) {
 -             if (j%15 == 0) {
 - 	        memset(buf, 0xff, 80);
 - 	        buf += dv_write_dif_id(dv_sect_audio, i, j/15, buf);
 -                 buf += 77; /* audio control & shuffled PCM audio */
 - 	    }
 - 	    buf += dv_write_dif_id(dv_sect_video, i, j, buf);
 - 	    buf += 77; /* 1 video macro block: 1 bytes control
 - 			                       4 * 14 bytes Y 8x8 data
 - 			                           10 bytes Cr 8x8 data
 - 						   10 bytes Cb 8x8 data */
 -        }
 -     }
 - }
 - 
 - static void dv_inject_audio(DVMuxContext *c, const uint8_t* pcm, uint8_t* frame_ptr)
 - {
 -     int i, j, d, of, size;
 -     size = 4 * dv_audio_frame_size(c->sys, c->frames);
 -     for (i = 0; i < c->sys->difseg_size; i++) {
 -        frame_ptr += 6 * 80; /* skip DIF segment header */
 -        for (j = 0; j < 9; j++) {
 - 	  dv_write_pack(dv_aaux_packs_dist[i][j], c, &frame_ptr[3]);
 -           for (d = 8; d < 80; d+=2) {
 - 	     of = c->sys->audio_shuffle[i][j] + (d - 8)/2 * c->sys->audio_stride;
 - 	     if (of*2 >= size)
 - 	         continue;
 - 	     
 - 	     frame_ptr[d] = pcm[of*2+1]; // FIXME: may be we have to admit
 - 	     frame_ptr[d+1] = pcm[of*2]; //        that DV is a big endian PCM       
 -           }
 -           frame_ptr += 16 * 80; /* 15 Video DIFs + 1 Audio DIF */
 -        }
 -     }
 - }
 - 
 - static void dv_inject_video(DVMuxContext *c, const uint8_t* video_data, uint8_t* frame_ptr)
 - {
 -     int i, j;
 -     int ptr = 0;
 - 
 -     for (i = 0; i < c->sys->difseg_size; i++) {
 -        ptr += 6 * 80; /* skip DIF segment header */
 -        for (j = 0; j < 135; j++) {
 -             if (j%15 == 0)
 - 	        ptr += 80; /* skip Audio DIF */
 - 	    ptr += 3;
 - 	    memcpy(frame_ptr + ptr, video_data + ptr, 77);
 - 	    ptr += 77;
 -        }
 -     }
 - }
 - 
 - /* 
 -  * This is the dumbest implementation of all -- it simply looks at
 -  * a fixed offset and if pack isn't there -- fails. We might want
 -  * to have a fallback mechanism for complete search of missing packs.
 -  */
 - static const uint8_t* dv_extract_pack(uint8_t* frame, enum dv_pack_type t)
 - {
 -     int offs;
 -     
 -     switch (t) {
 -     case dv_audio_source:
 -           offs = (80*6 + 80*16*3 + 3);
 - 	  break;
 -     case dv_audio_control:
 -           offs = (80*6 + 80*16*4 + 3);
 - 	  break;
 -     case dv_video_control:
 -           offs = (80*5 + 48 + 5);
 -           break;
 -     default:
 -           return NULL;
 -     }   
 - 
 -     return (frame[offs] == t ? &frame[offs] : NULL);
 - }
 - 
 - /* 
 -  * There's a couple of assumptions being made here:
 -  * 1. By default we silence erroneous (0x8000/16bit 0x800/12bit) audio samples.
 -  *    We can pass them upwards when ffmpeg will be ready to deal with them.
 -  * 2. We don't do software emphasis.
 -  * 3. Audio is always returned as 16bit linear samples: 12bit nonlinear samples
 -  *    are converted into 16bit linear ones.
 -  */
 - static int dv_extract_audio(uint8_t* frame, uint8_t* pcm, uint8_t* pcm2)
 - {
 -     int size, i, j, d, of, smpls, freq, quant, half_ch;
 -     uint16_t lc, rc;
 -     const DVprofile* sys;
 -     const uint8_t* as_pack;
 -     
 -     as_pack = dv_extract_pack(frame, dv_audio_source);
 -     if (!as_pack)    /* No audio ? */
 - 	return 0;
 -    
 -     sys = dv_frame_profile(frame);
 -     smpls = as_pack[1] & 0x3f; /* samples in this frame - min. samples */
 -     freq = (as_pack[4] >> 3) & 0x07; /* 0 - 48KHz, 1 - 44,1kHz, 2 - 32 kHz */
 -     quant = as_pack[4] & 0x07; /* 0 - 16bit linear, 1 - 12bit nonlinear */
 -     
 -     if (quant > 1)
 - 	return -1; /* Unsupported quantization */
 - 
 -     size = (sys->audio_min_samples[freq] + smpls) * 4; /* 2ch, 2bytes */
 -     half_ch = sys->difseg_size/2;
 - 
 -     /* for each DIF segment */
 -     for (i = 0; i < sys->difseg_size; i++) {
 -        frame += 6 * 80; /* skip DIF segment header */
 -        if (quant == 1 && i == half_ch) {
 -            if (!pcm2)
 -                break;
 -            else
 -                pcm = pcm2;
 -        }
 - 
 -        for (j = 0; j < 9; j++) {
 -           for (d = 8; d < 80; d += 2) {
 - 	     if (quant == 0) {  /* 16bit quantization */
 - 		 of = sys->audio_shuffle[i][j] + (d - 8)/2 * sys->audio_stride;
 -                  if (of*2 >= size)
 - 		     continue;
 - 		 
 - 		 pcm[of*2] = frame[d+1]; // FIXME: may be we have to admit
 - 		 pcm[of*2+1] = frame[d]; //        that DV is a big endian PCM
 - 		 if (pcm[of*2+1] == 0x80 && pcm[of*2] == 0x00)
 - 		     pcm[of*2+1] = 0;
 - 	      } else {           /* 12bit quantization */
 - 		 lc = ((uint16_t)frame[d] << 4) | 
 - 		      ((uint16_t)frame[d+2] >> 4);
 - 		 rc = ((uint16_t)frame[d+1] << 4) |
 - 	              ((uint16_t)frame[d+2] & 0x0f);
 - 		 lc = (lc == 0x800 ? 0 : dv_audio_12to16(lc));
 - 		 rc = (rc == 0x800 ? 0 : dv_audio_12to16(rc));
 - 
 - 		 of = sys->audio_shuffle[i%half_ch][j] + (d - 8)/3 * sys->audio_stride;
 -                  if (of*2 >= size)
 - 		     continue;
 - 
 - 		 pcm[of*2] = lc & 0xff; // FIXME: may be we have to admit
 - 		 pcm[of*2+1] = lc >> 8; //        that DV is a big endian PCM
 - 		 of = sys->audio_shuffle[i%half_ch+half_ch][j] + 
 - 		      (d - 8)/3 * sys->audio_stride;
 - 		 pcm[of*2] = rc & 0xff; // FIXME: may be we have to admit
 - 		 pcm[of*2+1] = rc >> 8; //        that DV is a big endian PCM
 - 		 ++d;
 - 	      }
 - 	  }
 - 		
 - 	  frame += 16 * 80; /* 15 Video DIFs + 1 Audio DIF */
 -         }
 -     }
 - 
 -     return size;
 - }
 - 
 - static int dv_extract_audio_info(DVDemuxContext* c, uint8_t* frame)
 - {
 -     const uint8_t* as_pack;
 -     const DVprofile* sys;
 -     int freq, smpls, quant, i, ach;
 - 
 -     sys = dv_frame_profile(frame);
 -     as_pack = dv_extract_pack(frame, dv_audio_source);
 -     if (!as_pack || !sys) {    /* No audio ? */
 -         c->ach = 0;
 - 	return 0;
 -     }
 -     
 -     smpls = as_pack[1] & 0x3f; /* samples in this frame - min. samples */
 -     freq = (as_pack[4] >> 3) & 0x07; /* 0 - 48KHz, 1 - 44,1kHz, 2 - 32 kHz */
 -     quant = as_pack[4] & 0x07; /* 0 - 16bit linear, 1 - 12bit nonlinear */
 -     ach = (quant && freq == 2) ? 2 : 1;
 - 
 -     /* Dynamic handling of the audio streams in DV */
 -     for (i=0; i<ach; i++) {
 -        if (!c->ast[i]) {
 -            c->ast[i] = av_new_stream(c->fctx, 0);
 - 	   if (!c->ast[i])
 - 	       break;
 - 	   av_set_pts_info(c->ast[i], 64, 1, 30000);
 - 	   c->ast[i]->codec->codec_type = CODEC_TYPE_AUDIO;
 - 	   c->ast[i]->codec->codec_id = CODEC_ID_PCM_S16LE;
 - 
 -            av_init_packet(&c->audio_pkt[i]);
 -            c->audio_pkt[i].size     = 0;
 -            c->audio_pkt[i].data     = c->audio_buf[i];
 -            c->audio_pkt[i].stream_index = c->ast[i]->index;
 -            c->audio_pkt[i].flags |= PKT_FLAG_KEY;
 -        }
 -        c->ast[i]->codec->sample_rate = dv_audio_frequency[freq];
 -        c->ast[i]->codec->channels = 2;
 -        c->ast[i]->codec->bit_rate = 2 * dv_audio_frequency[freq] * 16;
 -        c->ast[i]->start_time = 0;
 -     }
 -     c->ach = i;
 -     
 -     return (sys->audio_min_samples[freq] + smpls) * 4; /* 2ch, 2bytes */;
 - }
 - 
 - static int dv_extract_video_info(DVDemuxContext *c, uint8_t* frame)
 - {
 -     const DVprofile* sys; 
 -     const uint8_t* vsc_pack;
 -     AVCodecContext* avctx;
 -     int apt, is16_9;
 -     int size = 0;
 -     
 -     sys = dv_frame_profile(frame);
 -     if (sys) {
 -         avctx = c->vst->codec;
 - 	
 -         av_set_pts_info(c->vst, 64, sys->frame_rate_base, sys->frame_rate);
 -         avctx->time_base= (AVRational){sys->frame_rate_base, sys->frame_rate};
 -         avctx->width = sys->width;
 -         avctx->height = sys->height;
 -         avctx->pix_fmt = sys->pix_fmt;
 -         
 - 	/* finding out SAR is a little bit messy */
 - 	vsc_pack = dv_extract_pack(frame, dv_video_control);
 -         apt = frame[4] & 0x07;
 - 	is16_9 = (vsc_pack && ((vsc_pack[2] & 0x07) == 0x02 ||
 - 	                       (!apt && (vsc_pack[2] & 0x07) == 0x07)));
 - 	avctx->sample_aspect_ratio = sys->sar[is16_9];
 - 	
 - 	size = sys->frame_size;
 -     }
 -     return size;
 - }
 - 
 - /* 
 -  * The following 6 functions constitute our interface to the world
 -  */
 - 
 - int dv_assemble_frame(DVMuxContext *c, AVStream* st,
 -                       const uint8_t* data, int data_size, uint8_t** frame)
 - {
 -     uint8_t pcm[8192];
 -     int fsize, reqasize;
 -    
 -     *frame = &c->frame_buf[0];
 -     if (c->has_audio && c->has_video) {  /* must be a stale frame */
 -         dv_format_frame(c, *frame);
 - 	c->frames++;
 - 	if (c->has_audio > 0)
 - 	    c->has_audio = 0;
 - 	c->has_video = 0;
 -     }
 -     
 -     if (st->codec->codec_type == CODEC_TYPE_VIDEO) {
 -         /* FIXME: we have to have more sensible approach than this one */
 - 	if (c->has_video)
 - 	    av_log(st->codec, AV_LOG_ERROR, "Can't process DV frame #%d. Insufficient audio data or severe sync problem.\n", c->frames);
 - 	    
 -         dv_inject_video(c, data, *frame);
 - 	c->has_video = 1;
 - 	data_size = 0;
 - 	if (c->has_audio < 0)
 - 	    goto out;
 -     } 
 -     
 -     reqasize = 4 * dv_audio_frame_size(c->sys, c->frames);
 -     fsize = fifo_size(&c->audio_data, c->audio_data.rptr);
 -     if (st->codec->codec_type == CODEC_TYPE_AUDIO || (c->has_video && fsize >= reqasize)) { 
 - 	if (fsize + data_size >= reqasize && !c->has_audio) {
 -             if (fsize >= reqasize) {
 - 	        fifo_read(&c->audio_data, &pcm[0], reqasize, &c->audio_data.rptr);
 -             } else {
 - 	        fifo_read(&c->audio_data, &pcm[0], fsize, &c->audio_data.rptr);
 -                 memcpy(&pcm[fsize], &data[0], reqasize - fsize);
 - 		data += reqasize - fsize;
 - 		data_size -= reqasize - fsize;
 - 	    }
 - 	    dv_inject_audio(c, &pcm[0], *frame);
 - 	    c->has_audio = 1;
 - 	}
 -     
 -         /* FIXME: we have to have more sensible approach than this one */
 -         if (fifo_size(&c->audio_data, c->audio_data.rptr) + data_size >= 100*AVCODEC_MAX_AUDIO_FRAME_SIZE)
 - 	    av_log(st->codec, AV_LOG_ERROR, "Can't process DV frame #%d. Insufficient video data or severe sync problem.\n", c->frames);
 - 	fifo_write(&c->audio_data, (uint8_t *)data, data_size, &c->audio_data.wptr);
 -     }
 - 
 - out:
 -     return (c->has_audio && c->has_video) ? c->sys->frame_size : 0;
 - }
 - 
 - DVMuxContext* dv_init_mux(AVFormatContext* s)
 - {
 -     DVMuxContext *c;
 -     AVStream *vst = NULL;
 -     AVStream *ast = NULL;
 -     int i;
 - 
 -     if (s->nb_streams > 2)
 -         return NULL;
 - 
 -     c = av_mallocz(sizeof(DVMuxContext));
 -     if (!c)
 -         return NULL;
 - 
 -     /* We have to sort out where audio and where video stream is */
 -     for (i=0; i<s->nb_streams; i++) {
 -          switch (s->streams[i]->codec->codec_type) {
 - 	 case CODEC_TYPE_VIDEO:
 - 	       vst = s->streams[i];
 - 	       break;
 - 	 case CODEC_TYPE_AUDIO:
 - 	       ast = s->streams[i];
 - 	       break;
 - 	 default:
 - 	       goto bail_out;
 - 	 }
 -     }
 -     
 -     /* Some checks -- DV format is very picky about its incoming streams */
 -     if (!vst || vst->codec->codec_id != CODEC_ID_DVVIDEO)
 -         goto bail_out;
 -     if (ast  && (ast->codec->codec_id != CODEC_ID_PCM_S16LE ||
 - 	         ast->codec->sample_rate != 48000 ||
 - 	         ast->codec->channels != 2))
 - 	goto bail_out;
 -     c->sys = dv_codec_profile(vst->codec);
 -     if (!c->sys)
 - 	goto bail_out;
 -     
 -     /* Ok, everything seems to be in working order */
 -     c->frames = 0;
 -     c->has_audio = ast ? 0 : -1;
 -     c->has_video = 0;
 -     c->start_time = (time_t)s->timestamp;
 -     c->aspect = 0; /* 4:3 is the default */
 -     if ((int)(av_q2d(vst->codec->sample_aspect_ratio) * vst->codec->width / vst->codec->height * 10) == 17) /* 16:9 */ 
 -         c->aspect = 0x07;
 - 
 -     if (ast && fifo_init(&c->audio_data, 100*AVCODEC_MAX_AUDIO_FRAME_SIZE) < 0)
 -         goto bail_out;
 - 
 -     dv_format_frame(c, &c->frame_buf[0]);
 - 
 -     return c;
 -     
 - bail_out:
 -     av_free(c);
 -     return NULL;
 - }
 - 
 - void dv_delete_mux(DVMuxContext *c)
 - {    
 -     fifo_free(&c->audio_data);
 - }
 - 
 - DVDemuxContext* dv_init_demux(AVFormatContext *s)
 - {
 -     DVDemuxContext *c;
 - 
 -     c = av_mallocz(sizeof(DVDemuxContext));
 -     if (!c)
 -         return NULL;
 - 
 -     c->vst = av_new_stream(s, 0);
 -     if (!c->vst) {
 -         av_free(c);        
 -         return NULL;
 -     }
 - 
 -     c->fctx = s;
 -     c->ast[0] = c->ast[1] = NULL;
 -     c->ach = 0;
 -     c->frames = 0;
 -     c->abytes = 0;
 - 
 -     c->vst->codec->codec_type = CODEC_TYPE_VIDEO;
 -     c->vst->codec->codec_id = CODEC_ID_DVVIDEO;
 -     c->vst->codec->bit_rate = 25000000;
 -     c->vst->start_time = 0;
 -     
 -     return c;
 - }
 - 
 - int dv_get_packet(DVDemuxContext *c, AVPacket *pkt)
 - {
 -     int size = -1;
 -     int i;
 - 
 -     for (i=0; i<c->ach; i++) {
 -        if (c->ast[i] && c->audio_pkt[i].size) {
 -            *pkt = c->audio_pkt[i];
 - 	   c->audio_pkt[i].size = 0;
 - 	   size = pkt->size;
 - 	   break;
 -        }
 -     }
 - 
 -     return size;
 - }
 - 
 - int dv_produce_packet(DVDemuxContext *c, AVPacket *pkt, 
 -                       uint8_t* buf, int buf_size)
 - {
 -     int size, i;
 -     const DVprofile* sys = dv_frame_profile(buf);
 -    
 -     if (buf_size < 4 || buf_size < sys->frame_size)
 -         return -1;   /* Broken frame, or not enough data */
 - 
 -     /* Queueing audio packet */
 -     /* FIXME: in case of no audio/bad audio we have to do something */
 -     size = dv_extract_audio_info(c, buf);
 -     for (i=0; i<c->ach; i++) {
 -        c->audio_pkt[i].size = size;
 -        c->audio_pkt[i].pts  = c->abytes * 30000*8 / c->ast[i]->codec->bit_rate;
 -     }
 -     dv_extract_audio(buf, c->audio_buf[0], c->audio_buf[1]);
 -     c->abytes += size;
 -     
 -     /* Now it's time to return video packet */
 -     size = dv_extract_video_info(c, buf);
 -     av_init_packet(pkt);
 -     pkt->data     = buf;
 -     pkt->size     = size; 
 -     pkt->flags   |= PKT_FLAG_KEY;
 -     pkt->stream_index = c->vst->id;
 -     pkt->pts      = c->frames;
 -     
 -     c->frames++;
 - 
 -     return size;
 - }
 -                            
 - static int64_t dv_frame_offset(AVFormatContext *s, DVDemuxContext *c,
 -                               int64_t timestamp, int flags)
 - {
 -     // FIXME: sys may be wrong if last dv_read_packet() failed (buffer is junk)
 -     const DVprofile* sys = dv_codec_profile(c->vst->codec);
 -     int64_t offset;
 -     int64_t size = url_fsize(&s->pb);
 -     int64_t max_offset = ((size-1) / sys->frame_size) * sys->frame_size;
 - 
 -     offset = sys->frame_size * timestamp;
 -     
 -     if (offset > max_offset) offset = max_offset;
 -     else if (offset < 0) offset = 0;
 - 
 -     return offset;
 - }
 - 
 - void dv_flush_audio_packets(DVDemuxContext *c)
 - {
 -     c->audio_pkt[0].size = c->audio_pkt[1].size = 0;
 - }
 - 
 - /************************************************************
 -  * Implementation of the easiest DV storage of all -- raw DV.
 -  ************************************************************/
 -  
 - typedef struct RawDVContext {
 -     uint8_t         buf[144000];
 -     DVDemuxContext* dv_demux;
 - } RawDVContext;
 - 
 - static int dv_read_header(AVFormatContext *s,
 -                           AVFormatParameters *ap)
 - {
 -     RawDVContext *c = s->priv_data;
 -     const DVprofile* sys;
 -     c->dv_demux = dv_init_demux(s);
 -     if (!c->dv_demux)
 -         return -1;
 -    
 -     if (get_buffer(&s->pb, c->buf, 4) <= 0 || url_fseek(&s->pb, -4, SEEK_CUR) < 0)
 -         return AVERROR_IO;
 - 
 -     sys = dv_frame_profile(c->buf);
 -     s->bit_rate = av_rescale(sys->frame_size * 8, sys->frame_rate, sys->frame_rate_base);
 -    
 -     return 0;
 - }
 - 
 - 
 - static int dv_read_packet(AVFormatContext *s, AVPacket *pkt)
 - {
 -     int size;
 -     RawDVContext *c = s->priv_data; 
 -   
 -     size = dv_get_packet(c->dv_demux, pkt);
 -     
 -     if (size < 0) {
 -         if (get_buffer(&s->pb, c->buf, 4) <= 0) 
 -             return AVERROR_IO;
 -     
 -         size = dv_frame_profile(c->buf)->frame_size;
 -         if (get_buffer(&s->pb, c->buf + 4, size - 4) <= 0)
 - 	    return AVERROR_IO;
 - 
 - 	size = dv_produce_packet(c->dv_demux, pkt, c->buf, size);
 -     } 
 -     
 -     return size;
 - }
 - 
 - static int dv_read_seek(AVFormatContext *s, int stream_index, 
 -                        int64_t timestamp, int flags)
 - {
 -     RawDVContext *r = s->priv_data;
 -     DVDemuxContext *c = r->dv_demux;
 -     int64_t offset= dv_frame_offset(s, c, timestamp, flags);
 -     const DVprofile* sys = dv_codec_profile(c->vst->codec);
 - 
 -     c->frames= offset / sys->frame_size;
 -     if (c->ach)
 -         c->abytes= av_rescale(c->frames,
 -                           c->ast[0]->codec->bit_rate * (int64_t)sys->frame_rate_base,
 -                           8*sys->frame_rate);
 - 			  
 -     dv_flush_audio_packets(c);
 -     return url_fseek(&s->pb, offset, SEEK_SET);
 - }
 - 
 - static int dv_read_close(AVFormatContext *s)
 - {
 -     RawDVContext *c = s->priv_data;
 -     av_free(c->dv_demux);
 -     return 0;
 - }
 - 
 - static int dv_write_header(AVFormatContext *s)
 - {
 -     s->priv_data = dv_init_mux(s);
 -     if (!s->priv_data) {
 -         av_log(s, AV_LOG_ERROR, "Can't initialize DV format!\n"
 - 		    "Make sure that you supply exactly two streams:\n"
 - 		    "     video: 25fps or 29.97fps, audio: 2ch/48Khz/PCM\n");
 - 	return -1;
 -     }
 -     return 0;
 - }
 - 
 - static int dv_write_packet(struct AVFormatContext *s, AVPacket *pkt)
 - {
 -     uint8_t* frame;
 -     int fsize;
 -    
 -     fsize = dv_assemble_frame((DVMuxContext *)s->priv_data, s->streams[pkt->stream_index],
 -                               pkt->data, pkt->size, &frame);
 -     if (fsize > 0) {
 -         put_buffer(&s->pb, frame, fsize); 
 -         put_flush_packet(&s->pb);
 -     } 
 -     return 0;
 - }
 - 
 - /* 
 -  * We might end up with some extra A/V data without matching counterpart.
 -  * E.g. video data without enough audio to write the complete frame.
 -  * Currently we simply drop the last frame. I don't know whether this 
 -  * is the best strategy of all
 -  */
 - static int dv_write_trailer(struct AVFormatContext *s)
 - {
 -     dv_delete_mux((DVMuxContext *)s->priv_data);
 -     return 0;
 - }
 - 
 - static AVInputFormat dv_iformat = {
 -     "dv",
 -     "DV video format",
 -     sizeof(RawDVContext),
 -     NULL,
 -     dv_read_header,
 -     dv_read_packet,
 -     dv_read_close,
 -     dv_read_seek,
 -     .extensions = "dv,dif",
 - };
 - 
 - static AVOutputFormat dv_oformat = {
 -     "dv",
 -     "DV video format",
 -     NULL,
 -     "dv",
 -     sizeof(DVMuxContext),
 -     CODEC_ID_PCM_S16LE,
 -     CODEC_ID_DVVIDEO,
 -     dv_write_header,
 -     dv_write_packet,
 -     dv_write_trailer,
 - };
 - 
 - int ff_dv_init(void)
 - {
 -     av_register_input_format(&dv_iformat);
 -     av_register_output_format(&dv_oformat);
 -     return 0;
 - }
 
 
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