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FFmpeg/libavformat/dv.c

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  1. /* 

  2.  * General DV muxer/demuxer 

  3.  * Copyright (c) 2003 Roman Shaposhnick

  4.  *

  5.  * Many thanks to Dan Dennedy <dan@dennedy.org> for providing wealth

  6.  * of DV technical info.

  7.  *

  8.  * Raw DV format

  9.  * Copyright (c) 2002 Fabrice Bellard.

  10.  *

  11.  * This library is free software; you can redistribute it and/or

  12.  * modify it under the terms of the GNU Lesser General Public

  13.  * License as published by the Free Software Foundation; either

  14.  * version 2 of the License, or (at your option) any later version.

  15.  *

  16.  * This library is distributed in the hope that it will be useful,

  17.  * but WITHOUT ANY WARRANTY; without even the implied warranty of

  18.  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU

  19.  * Lesser General Public License for more details.

  20.  *

  21.  * You should have received a copy of the GNU Lesser General Public

  22.  * License along with this library; if not, write to the Free Software

  23.  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA

  24.  */

  25. #include <time.h>

  26. #include "avformat.h"

  27. #include "dvdata.h"

  28. #include "dv.h"

  29. 

  30. struct DVDemuxContext {

  31.     AVFormatContext* fctx;

  32.     AVStream*        vst;

  33.     AVStream*        ast[2];       

  34.     AVPacket         audio_pkt[2];

  35.     int              ach;

  36.     int              frames;

  37.     uint64_t         abytes;

  38. };

  39. 

  40. struct DVMuxContext {

  41.     const DVprofile*  sys;    /* Current DV profile. E.g.: 525/60, 625/50 */

  42.     uint8_t     frame_buf[144000]; /* frame under contruction */

  43.     FifoBuffer  audio_data;   /* Fifo for storing excessive amounts of PCM */

  44.     int         frames;       /* Number of a current frame */

  45.     time_t      start_time;   /* Start time of recording */

  46.     uint8_t     aspect;       /* Aspect ID 0 - 4:3, 7 - 16:9 */

  47.     int         has_audio;    /* frame under contruction has audio */

  48.     int         has_video;    /* frame under contruction has video */

  49. };

  50. 

  51. enum dv_section_type {

  52.      dv_sect_header  = 0x1f,

  53.      dv_sect_subcode = 0x3f,

  54.      dv_sect_vaux    = 0x56,

  55.      dv_sect_audio   = 0x76,

  56.      dv_sect_video   = 0x96,

  57. };

  58. 

  59. enum dv_pack_type {

  60.      dv_header525     = 0x3f, /* see dv_write_pack for important details on */ 

  61.      dv_header625     = 0xbf, /* these two packs */

  62.      dv_timecode      = 0x13,

  63.      dv_audio_source  = 0x50,

  64.      dv_audio_control = 0x51,

  65.      dv_audio_recdate = 0x52,

  66.      dv_audio_rectime = 0x53,

  67.      dv_video_source  = 0x60,

  68.      dv_video_control = 0x61,

  69.      dv_viedo_recdate = 0x62,

  70.      dv_video_rectime = 0x63,

  71.      dv_unknown_pack  = 0xff,

  72. };

  73. 

  74. 

  75. 

  76. /*

  77.  * The reason why the following three big ugly looking tables are

  78.  * here is my lack of DV spec IEC 61834. The tables were basically 

  79.  * constructed to make code that places packs in SSYB, VAUX and 

  80.  * AAUX blocks very simple and table-driven. They conform to the

  81.  * SMPTE 314M and the output of my personal DV camcorder, neither

  82.  * of which is sufficient for a reliable DV stream producing. Thus

  83.  * while code is still in development I'll be gathering input from

  84.  * people with different DV equipment and modifying the tables to

  85.  * accommodate all the quirks. Later on, if possible, some of them

  86.  * will be folded into smaller tables and/or switch-if logic. For 

  87.  * now, my only excuse is -- they don't eat up that much of a space.

  88.  */

  89. 

  90. static const int dv_ssyb_packs_dist[12][6] = {

  91.     { 0x13, 0x13, 0x13, 0x13, 0x13, 0x13 },

  92.     { 0x13, 0x13, 0x13, 0x13, 0x13, 0x13 },

  93.     { 0x13, 0x13, 0x13, 0x13, 0x13, 0x13 },

  94.     { 0x13, 0x13, 0x13, 0x13, 0x13, 0x13 },

  95.     { 0x13, 0x13, 0x13, 0x13, 0x13, 0x13 },

  96.     { 0x13, 0x13, 0x13, 0x13, 0x13, 0x13 },

  97.     { 0x13, 0x62, 0x63, 0x13, 0x62, 0x63 },

  98.     { 0x13, 0x62, 0x63, 0x13, 0x62, 0x63 },

  99.     { 0x13, 0x62, 0x63, 0x13, 0x62, 0x63 },

  100.     { 0x13, 0x62, 0x63, 0x13, 0x62, 0x63 },

  101.     { 0x13, 0x62, 0x63, 0x13, 0x62, 0x63 },

  102.     { 0x13, 0x62, 0x63, 0x13, 0x62, 0x63 },

  103. };

  104. 

  105. static const int dv_vaux_packs_dist[12][15] = {

  106.     { 0x60, 0x61, 0x62, 0x63, 0xff, 0xff, 0xff, 0xff, 0xff, 

  107.       0x60, 0x61, 0x62, 0x63, 0xff, 0xff },

  108.     { 0x60, 0x61, 0x62, 0x63, 0xff, 0xff, 0xff, 0xff, 0xff, 

  109.       0x60, 0x61, 0x62, 0x63, 0xff, 0xff },

  110.     { 0x60, 0x61, 0x62, 0x63, 0xff, 0xff, 0xff, 0xff, 0xff, 

  111.       0x60, 0x61, 0x62, 0x63, 0xff, 0xff },

  112.     { 0x60, 0x61, 0x62, 0x63, 0xff, 0xff, 0xff, 0xff, 0xff, 

  113.       0x60, 0x61, 0x62, 0x63, 0xff, 0xff },

  114.     { 0x60, 0x61, 0x62, 0x63, 0xff, 0xff, 0xff, 0xff, 0xff, 

  115.       0x60, 0x61, 0x62, 0x63, 0xff, 0xff },

  116.     { 0x60, 0x61, 0x62, 0x63, 0xff, 0xff, 0xff, 0xff, 0xff, 

  117.       0x60, 0x61, 0x62, 0x63, 0xff, 0xff },

  118.     { 0x60, 0x61, 0x62, 0x63, 0xff, 0xff, 0xff, 0xff, 0xff, 

  119.       0x60, 0x61, 0x62, 0x63, 0xff, 0xff },

  120.     { 0x60, 0x61, 0x62, 0x63, 0xff, 0xff, 0xff, 0xff, 0xff, 

  121.       0x60, 0x61, 0x62, 0x63, 0xff, 0xff },

  122.     { 0x60, 0x61, 0x62, 0x63, 0xff, 0xff, 0xff, 0xff, 0xff, 

  123.       0x60, 0x61, 0x62, 0x63, 0xff, 0xff },

  124.     { 0x60, 0x61, 0x62, 0x63, 0xff, 0xff, 0xff, 0xff, 0xff, 

  125.       0x60, 0x61, 0x62, 0x63, 0xff, 0xff },

  126.     { 0x60, 0x61, 0x62, 0x63, 0xff, 0xff, 0xff, 0xff, 0xff, 

  127.       0x60, 0x61, 0x62, 0x63, 0xff, 0xff },

  128.     { 0x60, 0x61, 0x62, 0x63, 0xff, 0xff, 0xff, 0xff, 0xff, 

  129.       0x60, 0x61, 0x62, 0x63, 0xff, 0xff },

  130. };

  131. 

  132. static const int dv_aaux_packs_dist[12][9] = {

  133.     { 0xff, 0xff, 0xff, 0x50, 0x51, 0x52, 0x53, 0xff, 0xff },

  134.     { 0x50, 0x51, 0x52, 0x53, 0xff, 0xff, 0xff, 0xff, 0xff },

  135.     { 0xff, 0xff, 0xff, 0x50, 0x51, 0x52, 0x53, 0xff, 0xff },

  136.     { 0x50, 0x51, 0x52, 0x53, 0xff, 0xff, 0xff, 0xff, 0xff },

  137.     { 0xff, 0xff, 0xff, 0x50, 0x51, 0x52, 0x53, 0xff, 0xff },

  138.     { 0x50, 0x51, 0x52, 0x53, 0xff, 0xff, 0xff, 0xff, 0xff },

  139.     { 0xff, 0xff, 0xff, 0x50, 0x51, 0x52, 0x53, 0xff, 0xff },

  140.     { 0x50, 0x51, 0x52, 0x53, 0xff, 0xff, 0xff, 0xff, 0xff },

  141.     { 0xff, 0xff, 0xff, 0x50, 0x51, 0x52, 0x53, 0xff, 0xff },

  142.     { 0x50, 0x51, 0x52, 0x53, 0xff, 0xff, 0xff, 0xff, 0xff },

  143.     { 0xff, 0xff, 0xff, 0x50, 0x51, 0x52, 0x53, 0xff, 0xff },

  144.     { 0x50, 0x51, 0x52, 0x53, 0xff, 0xff, 0xff, 0xff, 0xff },

  145. };

  146. 

  147. static inline uint16_t dv_audio_12to16(uint16_t sample)

  148. {

  149.     uint16_t shift, result;

  150.     

  151.     sample = (sample < 0x800) ? sample : sample | 0xf000;

  152.     shift = (sample & 0xf00) >> 8;

  153. 

  154.     if (shift < 0x2 || shift > 0xd) {

  155. 	result = sample;

  156.     } else if (shift < 0x8) {

  157.         shift--;

  158. 	result = (sample - (256 * shift)) << shift;

  159.     } else {

  160. 	shift = 0xe - shift;

  161. 	result = ((sample + ((256 * shift) + 1)) << shift) - 1;

  162.     }

  163. 

  164.     return result;

  165. }

  166. 

  167. static int dv_audio_frame_size(const DVprofile* sys, int frame)

  168. {

  169.     return sys->audio_samples_dist[frame % (sizeof(sys->audio_samples_dist)/

  170. 		                            sizeof(sys->audio_samples_dist[0]))];

  171. }

  172. 

  173. static int dv_write_pack(enum dv_pack_type pack_id, DVMuxContext *c, uint8_t* buf)

  174. {

  175.     struct tm tc;

  176.     time_t ct;

  177.     int ltc_frame;

  178. 

  179.     buf[0] = (uint8_t)pack_id;

  180.     switch (pack_id) {

  181.     case dv_header525: /* I can't imagine why these two weren't defined as real */

  182.     case dv_header625: /* packs in SMPTE314M -- they definitely look like ones */

  183.           buf[1] = 0xf8 |               /* reserved -- always 1 */

  184. 	           (0 & 0x07);          /* APT: Track application ID */

  185.           buf[2] = (0 << 7)    | /* TF1: audio data is 0 - valid; 1 - invalid */

  186. 	           (0x0f << 3) | /* reserved -- always 1 */

  187. 		   (0 & 0x07);   /* AP1: Audio application ID */

  188.           buf[3] = (0 << 7)    | /* TF2: video data is 0 - valid; 1 - invalid */  

  189. 	           (0x0f << 3) | /* reserved -- always 1 */

  190. 		   (0 & 0x07);   /* AP2: Video application ID */

  191.           buf[4] = (0 << 7)    | /* TF3: subcode(SSYB) is 0 - valid; 1 - invalid */ 

  192. 	           (0x0f << 3) | /* reserved -- always 1 */

  193. 		   (0 & 0x07);   /* AP3: Subcode application ID */

  194. 	  break;

  195.     case dv_timecode:

  196.           ct = (time_t)(c->frames / ((float)c->sys->frame_rate / 

  197.                                      (float)c->sys->frame_rate_base));

  198.           brktimegm(ct, &tc);

  199.           /* 

  200.            * LTC drop-frame frame counter drops two frames (0 and 1) every 

  201.            * minute, unless it is exactly divisible by 10

  202.            */

  203.           ltc_frame = (c->frames + 2*ct/60 - 2*ct/600) % c->sys->ltc_divisor;

  204. 	  buf[1] = (0 << 7) | /* Color fame: 0 - unsync; 1 - sync mode */

  205. 		   (1 << 6) | /* Drop frame timecode: 0 - nondrop; 1 - drop */

  206. 		   ((ltc_frame / 10) << 4) | /* Tens of frames */

  207. 		   (ltc_frame % 10);         /* Units of frames */

  208. 	  buf[2] = (1 << 7) | /* Biphase mark polarity correction: 0 - even; 1 - odd */

  209. 		   ((tc.tm_sec / 10) << 4) | /* Tens of seconds */

  210. 		   (tc.tm_sec % 10);         /* Units of seconds */

  211. 	  buf[3] = (1 << 7) | /* Binary group flag BGF0 */

  212. 		   ((tc.tm_min / 10) << 4) | /* Tens of minutes */

  213. 		   (tc.tm_min % 10);         /* Units of minutes */

  214. 	  buf[4] = (1 << 7) | /* Binary group flag BGF2 */

  215. 		   (1 << 6) | /* Binary group flag BGF1 */

  216. 	           ((tc.tm_hour / 10) << 4) | /* Tens of hours */

  217. 		   (tc.tm_hour % 10);         /* Units of hours */

  218.           break;

  219.     case dv_audio_source:  /* AAUX source pack */

  220.           buf[1] = (0 << 7) | /* locked mode       */

  221.                    (1 << 6) | /* reserved -- always 1 */

  222. 	           (dv_audio_frame_size(c->sys, c->frames) -

  223. 		    c->sys->audio_min_samples[0]);

  224. 	                      /* # of samples      */

  225.           buf[2] = (0 << 7) | /* multi-stereo      */

  226.                    (0 << 5) | /* #of audio channels per block: 0 -- 1 channel */

  227.                    (0 << 4) | /* pair bit: 0 -- one pair of channels */

  228. 	            0;        /* audio mode        */

  229.           buf[3] = (1 << 7) | /* res               */

  230.                    (1 << 6) | /* multi-language flag */

  231. 	           (c->sys->dsf << 5) | /*  system: 60fields/50fields */

  232. 	            0;        /* definition: 0 -- SD (525/625) */

  233.           buf[4] = (1 << 7) | /* emphasis: 1 -- off */

  234.                    (0 << 6) | /* emphasis time constant: 0 -- reserved */

  235. 	           (0 << 3) | /* frequency: 0 -- 48Khz, 1 -- 44,1Khz, 2 -- 32Khz */

  236.                     0;        /* quantization: 0 -- 16bit linear, 1 -- 12bit nonlinear */			    

  237.           break;

  238.     case dv_audio_control:

  239.           buf[1] = (0 << 6) | /* copy protection: 0 -- unrestricted */

  240.                    (1 << 4) | /* input source: 1 -- digital input */

  241. 	           (3 << 2) | /* compression: 3 -- no information */

  242. 	            0;        /* misc. info/SMPTE emphasis off */

  243.           buf[2] = (1 << 7) | /* recording start point: 1 -- no */

  244.                    (1 << 6) | /* recording end point: 1 -- no */

  245. 	           (1 << 3) | /* recording mode: 1 -- original */

  246. 	            7;         

  247.           buf[3] = (1 << 7) | /* direction: 1 -- forward */

  248.                     0x20;     /* speed */

  249.           buf[4] = (1 << 7) | /* reserved -- always 1 */

  250.                     0x7f;     /* genre category */

  251. 	  break;

  252.     case dv_audio_recdate:

  253.     case dv_viedo_recdate:  /* VAUX recording date */

  254.           ct = c->start_time + (time_t)(c->frames / 

  255. 	       ((float)c->sys->frame_rate / (float)c->sys->frame_rate_base));

  256.           brktimegm(ct, &tc);

  257. 	  buf[1] = 0xff; /* ds, tm, tens of time zone, units of time zone */

  258. 	                 /* 0xff is very likely to be "unknown" */

  259. 	  buf[2] = (3 << 6) | /* reserved -- always 1 */

  260. 		   ((tc.tm_mday / 10) << 4) | /* Tens of day */

  261. 		   (tc.tm_mday % 10);         /* Units of day */

  262. 	  buf[3] = /* we set high 4 bits to 0, shouldn't we set them to week? */

  263. 	           ((tc.tm_mon / 10) << 4) |    /* Tens of month */

  264. 		   (tc.tm_mon  % 10);           /* Units of month */

  265. 	  buf[4] = (((tc.tm_year % 100) / 10) << 4) | /* Tens of year */

  266. 		   (tc.tm_year % 10);                 /* Units of year */

  267.           break;

  268.     case dv_audio_rectime:  /* AAUX recording time */

  269.     case dv_video_rectime:  /* VAUX recording time */

  270.           ct = c->start_time + (time_t)(c->frames / 

  271. 	       ((float)c->sys->frame_rate / (float)c->sys->frame_rate_base));

  272. 	  brktimegm(ct, &tc);

  273. 	  buf[1] = (3 << 6) | /* reserved -- always 1 */

  274. 		   0x3f; /* tens of frame, units of frame: 0x3f - "unknown" ? */

  275. 	  buf[2] = (1 << 7) | /* reserved -- always 1 */ 

  276. 		   ((tc.tm_sec / 10) << 4) | /* Tens of seconds */

  277. 		   (tc.tm_sec % 10);         /* Units of seconds */

  278. 	  buf[3] = (1 << 7) | /* reserved -- always 1 */

  279. 		   ((tc.tm_min / 10) << 4) | /* Tens of minutes */

  280. 		   (tc.tm_min % 10);         /* Units of minutes */

  281. 	  buf[4] = (3 << 6) | /* reserved -- always 1 */ 

  282. 	           ((tc.tm_hour / 10) << 4) | /* Tens of hours */

  283. 		   (tc.tm_hour % 10);         /* Units of hours */

  284. 	  break;

  285.     case dv_video_source:

  286. 	  buf[1] = 0xff; /* reserved -- always 1 */

  287. 	  buf[2] = (1 << 7) | /* B/W: 0 - b/w, 1 - color */

  288. 		   (1 << 6) | /* following CLF is valid - 0, invalid - 1 */

  289. 		   (3 << 4) | /* CLF: color frames id (see ITU-R BT.470-4) */

  290. 		   0xf; /* reserved -- always 1 */

  291. 	  buf[3] = (3 << 6) | /* reserved -- always 1 */

  292. 		   (c->sys->dsf << 5) | /*  system: 60fields/50fields */

  293. 		   0; /* signal type video compression */

  294. 	  buf[4] = 0xff; /* VISC: 0xff -- no information */

  295.           break;

  296.     case dv_video_control:

  297. 	  buf[1] = (0 << 6) | /* Copy generation management (CGMS) 0 -- free */

  298. 		   0x3f; /* reserved -- always 1 */

  299. 	  buf[2] = 0xc8 | /* reserved -- always b11001xxx */

  300. 		   c->aspect;

  301. 	  buf[3] = (1 << 7) | /* Frame/field flag 1 -- frame, 0 -- field */

  302. 		   (1 << 6) | /* First/second field flag 0 -- field 2, 1 -- field 1 */

  303. 		   (1 << 5) | /* Frame change flag 0 -- same picture as before, 1 -- different */

  304. 		   (1 << 4) | /* 1 - interlaced, 0 - noninterlaced */

  305. 		   0xc; /* reserved -- always b1100 */

  306. 	  buf[4] = 0xff; /* reserved -- always 1 */

  307.           break;

  308.     default:

  309.           buf[1] = buf[2] = buf[3] = buf[4] = 0xff;

  310.     }

  311.     return 5;

  312. }

  313. 

  314. static inline int dv_write_dif_id(enum dv_section_type t, uint8_t seq_num, 

  315.                                   uint8_t dif_num, uint8_t* buf)

  316. {

  317.     buf[0] = (uint8_t)t;    /* Section type */

  318.     buf[1] = (seq_num<<4) | /* DIF seq number 0-9 for 525/60; 0-11 for 625/50 */

  319. 	     (0 << 3) |     /* FSC: for 50Mb/s 0 - first channel; 1 - second */

  320. 	     7;             /* reserved -- always 1 */

  321.     buf[2] = dif_num;       /* DIF block number Video: 0-134, Audio: 0-8 */

  322.     return 3;

  323. }

  324. 

  325. static inline int dv_write_ssyb_id(uint8_t syb_num, uint8_t fr, uint8_t* buf)

  326. {

  327.     if (syb_num == 0 || syb_num == 6) {

  328. 	buf[0] = (fr<<7) | /* FR ID 1 - first half of each channel; 0 - second */

  329. 		 (0<<4)  | /* AP3 (Subcode application ID) */

  330. 		 0x0f;     /* reserved -- always 1 */

  331.     } 

  332.     else if (syb_num == 11) {

  333. 	buf[0] = (fr<<7) | /* FR ID 1 - first half of each channel; 0 - second */

  334.                  0x7f;     /* reserved -- always 1 */

  335.     }

  336.     else {

  337. 	buf[0] = (fr<<7) | /* FR ID 1 - first half of each channel; 0 - second */

  338.                  (0<<4)  | /* APT (Track application ID) */

  339. 		 0x0f;     /* reserved -- always 1 */

  340.     }

  341.     buf[1] = 0xf0 |            /* reserved -- always 1 */

  342.              (syb_num & 0x0f); /* SSYB number 0 - 11   */

  343.     buf[2] = 0xff;             /* reserved -- always 1 */

  344.     return 3;

  345. }

  346. 

  347. static void dv_format_frame(DVMuxContext *c, uint8_t* buf)

  348. {

  349.     int i, j, k;

  350.     

  351.     for (i = 0; i < c->sys->difseg_size; i++) {

  352.        memset(buf, 0xff, 80 * 6); /* First 6 DIF blocks are for control data */

  353.        

  354.        /* DV header: 1DIF */

  355.        buf += dv_write_dif_id(dv_sect_header, i, 0, buf);

  356.        buf += dv_write_pack((c->sys->dsf ? dv_header625 : dv_header525), c, buf);

  357.        buf += 72; /* unused bytes */

  358. 				   

  359.        /* DV subcode: 2DIFs */

  360.        for (j = 0; j < 2; j++) {

  361.           buf += dv_write_dif_id( dv_sect_subcode, i, j, buf);

  362. 	  for (k = 0; k < 6; k++) {

  363. 	     buf += dv_write_ssyb_id(k, (i < c->sys->difseg_size/2), buf);

  364. 	     buf += dv_write_pack(dv_ssyb_packs_dist[i][k], c, buf);

  365. 	  }

  366. 	  buf += 29; /* unused bytes */

  367.        }

  368.        

  369.        /* DV VAUX: 3DIFs */

  370.        for (j = 0; j < 3; j++) {

  371. 	  buf += dv_write_dif_id(dv_sect_vaux, i, j, buf);

  372. 	  for (k = 0; k < 15 ; k++)

  373. 	     buf += dv_write_pack(dv_vaux_packs_dist[i][k], c, buf);

  374. 	  buf += 2; /* unused bytes */

  375.        } 

  376.        

  377.        /* DV Audio/Video: 135 Video DIFs + 9 Audio DIFs */

  378.        for (j = 0; j < 135; j++) {

  379.             if (j%15 == 0) {

  380. 	        buf += dv_write_dif_id(dv_sect_audio, i, j/15, buf);

  381. 	        buf += dv_write_pack(dv_aaux_packs_dist[i][j/15], c, buf);

  382. 		buf += 72; /* shuffled PCM audio */

  383. 	    }

  384. 	    buf += dv_write_dif_id(dv_sect_video, i, j, buf);

  385. 	    buf += 77; /* 1 video macro block: 1 bytes control

  386. 			                       4 * 14 bytes Y 8x8 data

  387. 			                           10 bytes Cr 8x8 data

  388. 						   10 bytes Cb 8x8 data */

  389.        }

  390.     }

  391. }

  392. 

  393. static void dv_inject_audio(DVMuxContext *c, const uint8_t* pcm, uint8_t* frame_ptr)

  394. {

  395.     int i, j, d, of, size;

  396.     size = 4 * dv_audio_frame_size(c->sys, c->frames);

  397.     for (i = 0; i < c->sys->difseg_size; i++) {

  398.        frame_ptr += 6 * 80; /* skip DIF segment header */

  399.        for (j = 0; j < 9; j++) {

  400.           for (d = 8; d < 80; d+=2) {

  401. 	     of = c->sys->audio_shuffle[i][j] + (d - 8)/2 * c->sys->audio_stride;

  402. 	     if (of*2 >= size)

  403. 	         continue;

  404. 	     

  405. 	     frame_ptr[d] = pcm[of*2+1]; // FIXME: may be we have to admit

  406. 	     frame_ptr[d+1] = pcm[of*2]; //        that DV is a big endian PCM       

  407.           }

  408.           frame_ptr += 16 * 80; /* 15 Video DIFs + 1 Audio DIF */

  409.        }

  410.     }

  411. }

  412. 

  413. static void dv_inject_video(DVMuxContext *c, const uint8_t* video_data, uint8_t* frame_ptr)

  414. {

  415.     int i, j;

  416.     int ptr = 0;

  417. 

  418.     for (i = 0; i < c->sys->difseg_size; i++) {

  419.        ptr += 6 * 80; /* skip DIF segment header */

  420.        for (j = 0; j < 135; j++) {

  421.             if (j%15 == 0)

  422. 	        ptr += 80; /* skip Audio DIF */

  423. 	    ptr += 3;

  424. 	    memcpy(frame_ptr + ptr, video_data + ptr, 77);

  425. 	    ptr += 77;

  426.        }

  427.     }

  428. }

  429. 

  430. /* 

  431.  * This is the dumbest implementation of all -- it simply looks at

  432.  * a fixed offset and if pack isn't there -- fails. We might want

  433.  * to have a fallback mechanism for complete search of missing packs.

  434.  */

  435. static const uint8_t* dv_extract_pack(uint8_t* frame, enum dv_pack_type t)

  436. {

  437.     int offs;

  438.     

  439.     switch (t) {

  440.     case dv_audio_source:

  441.           offs = (80*6 + 80*16*3 + 3);

  442. 	  break;

  443.     case dv_audio_control:

  444.           offs = (80*6 + 80*16*4 + 3);

  445. 	  break;

  446.     case dv_video_control:

  447.           offs = (80*5 + 48 + 5);

  448.           break;

  449.     default:

  450.           return NULL;

  451.     }   

  452. 

  453.     return (frame[offs] == t ? &frame[offs] : NULL);

  454. }

  455. 

  456. /* 

  457.  * There's a couple of assumptions being made here:

  458.  * 1. By default we silence erroneous (0x8000/16bit 0x800/12bit) audio samples.

  459.  *    We can pass them upwards when ffmpeg will be ready to deal with them.

  460.  * 2. We don't do software emphasis.

  461.  * 3. Audio is always returned as 16bit linear samples: 12bit nonlinear samples

  462.  *    are converted into 16bit linear ones.

  463.  */

  464. static int dv_extract_audio(uint8_t* frame, uint8_t* pcm, uint8_t* pcm2)

  465. {

  466.     int size, i, j, d, of, smpls, freq, quant, half_ch;

  467.     uint16_t lc, rc;

  468.     const DVprofile* sys;

  469.     const uint8_t* as_pack;

  470.     

  471.     as_pack = dv_extract_pack(frame, dv_audio_source);

  472.     if (!as_pack)    /* No audio ? */

  473. 	return 0;

  474.    

  475.     sys = dv_frame_profile(frame);

  476.     smpls = as_pack[1] & 0x3f; /* samples in this frame - min. samples */

  477.     freq = (as_pack[4] >> 3) & 0x07; /* 0 - 48KHz, 1 - 44,1kHz, 2 - 32 kHz */

  478.     quant = as_pack[4] & 0x07; /* 0 - 16bit linear, 1 - 12bit nonlinear */

  479.     

  480.     if (quant > 1)

  481. 	return -1; /* Unsupported quantization */

  482. 

  483.     size = (sys->audio_min_samples[freq] + smpls) * 4; /* 2ch, 2bytes */

  484.     half_ch = sys->difseg_size/2;

  485. 

  486.     /* for each DIF segment */

  487.     for (i = 0; i < sys->difseg_size; i++) {

  488.        frame += 6 * 80; /* skip DIF segment header */

  489.        if (quant == 1 && i == half_ch) {

  490.            if (!pcm2)

  491.                break;

  492.            else

  493.                pcm = pcm2;

  494.        }

  495. 

  496.        for (j = 0; j < 9; j++) {

  497.           for (d = 8; d < 80; d += 2) {

  498. 	     if (quant == 0) {  /* 16bit quantization */

  499. 		 of = sys->audio_shuffle[i][j] + (d - 8)/2 * sys->audio_stride;

  500.                  if (of*2 >= size)

  501. 		     continue;

  502. 		 

  503. 		 pcm[of*2] = frame[d+1]; // FIXME: may be we have to admit

  504. 		 pcm[of*2+1] = frame[d]; //        that DV is a big endian PCM

  505. 		 if (pcm[of*2+1] == 0x80 && pcm[of*2] == 0x00)

  506. 		     pcm[of*2+1] = 0;

  507. 	      } else {           /* 12bit quantization */

  508. 		 lc = ((uint16_t)frame[d] << 4) | 

  509. 		      ((uint16_t)frame[d+2] >> 4);

  510. 		 rc = ((uint16_t)frame[d+1] << 4) |

  511. 	              ((uint16_t)frame[d+2] & 0x0f);

  512. 		 lc = (lc == 0x800 ? 0 : dv_audio_12to16(lc));

  513. 		 rc = (rc == 0x800 ? 0 : dv_audio_12to16(rc));

  514. 

  515. 		 of = sys->audio_shuffle[i%half_ch][j] + (d - 8)/3 * sys->audio_stride;

  516.                  if (of*2 >= size)

  517. 		     continue;

  518. 

  519. 		 pcm[of*2] = lc & 0xff; // FIXME: may be we have to admit

  520. 		 pcm[of*2+1] = lc >> 8; //        that DV is a big endian PCM

  521. 		 of = sys->audio_shuffle[i%half_ch+half_ch][j] + 

  522. 		      (d - 8)/3 * sys->audio_stride;

  523. 		 pcm[of*2] = rc & 0xff; // FIXME: may be we have to admit

  524. 		 pcm[of*2+1] = rc >> 8; //        that DV is a big endian PCM

  525. 		 ++d;

  526. 	      }

  527. 	  }

  528. 		

  529. 	  frame += 16 * 80; /* 15 Video DIFs + 1 Audio DIF */

  530.         }

  531.     }

  532. 

  533.     return size;

  534. }

  535. 

  536. static int dv_extract_audio_info(DVDemuxContext* c, uint8_t* frame)

  537. {

  538.     const uint8_t* as_pack;

  539.     const DVprofile* sys;

  540.     int freq, smpls, quant, i;

  541. 

  542.     sys = dv_frame_profile(frame);

  543.     as_pack = dv_extract_pack(frame, dv_audio_source);

  544.     if (!as_pack || !sys) {    /* No audio ? */

  545.         c->ach = 0;

  546. 	return -1;

  547.     }

  548.     

  549.     smpls = as_pack[1] & 0x3f; /* samples in this frame - min. samples */

  550.     freq = (as_pack[4] >> 3) & 0x07; /* 0 - 48KHz, 1 - 44,1kHz, 2 - 32 kHz */

  551.     quant = as_pack[4] & 0x07; /* 0 - 16bit linear, 1 - 12bit nonlinear */

  552.     c->ach = (quant && freq == 2) ? 2 : 1;

  553. 

  554.     /* The second stereo channel could appear in IEC 61834 stream only */

  555.     if (c->ach == 2 && !c->ast[1]) {

  556.         c->ast[1] = av_new_stream(c->fctx, 0);

  557. 	if (c->ast[1]) {

  558.             av_set_pts_info(c->ast[1], 64, 1, 30000);

  559. 	    c->ast[1]->codec.codec_type = CODEC_TYPE_AUDIO;

  560. 	    c->ast[1]->codec.codec_id = CODEC_ID_PCM_S16LE;

  561. 	} else

  562. 	    c->ach = 1;

  563.     }

  564.     for (i=0; i<c->ach; i++) {

  565.        c->ast[i]->codec.sample_rate = dv_audio_frequency[freq];

  566.        c->ast[i]->codec.channels = 2;

  567.        c->ast[i]->codec.bit_rate = 2 * dv_audio_frequency[freq] * 16;

  568.     }

  569.     

  570.     return (sys->audio_min_samples[freq] + smpls) * 4; /* 2ch, 2bytes */;

  571. }

  572. 

  573. static int dv_extract_video_info(DVDemuxContext *c, uint8_t* frame)

  574. {

  575.     const DVprofile* sys; 

  576.     const uint8_t* vsc_pack;

  577.     AVCodecContext* avctx;

  578.     int apt, is16_9;

  579.     int size = 0;

  580.     

  581.     sys = dv_frame_profile(frame);

  582.     if (sys) {

  583.         avctx = &c->vst->codec;

  584. 	

  585. 	avctx->frame_rate = sys->frame_rate;

  586.         avctx->frame_rate_base = sys->frame_rate_base;

  587.         avctx->width = sys->width;

  588.         avctx->height = sys->height;

  589.         avctx->pix_fmt = sys->pix_fmt;

  590.         

  591. 	/* finding out SAR is a little bit messy */

  592. 	vsc_pack = dv_extract_pack(frame, dv_video_control);

  593.         apt = frame[4] & 0x07;

  594. 	is16_9 = (vsc_pack && ((vsc_pack[2] & 0x07) == 0x02 ||

  595. 	                       (!apt && (vsc_pack[2] & 0x07) == 0x07)));

  596. 	avctx->sample_aspect_ratio = sys->sar[is16_9];

  597. 	

  598. 	size = sys->frame_size;

  599.     }

  600.     return size;

  601. }

  602. 

  603. /* 

  604.  * The following 6 functions constitute our interface to the world

  605.  */

  606. 

  607. int dv_assemble_frame(DVMuxContext *c, AVStream* st,

  608.                       const uint8_t* data, int data_size, uint8_t** frame)

  609. {

  610.     uint8_t pcm[8192];

  611.     int fsize, reqasize;

  612.    

  613.     *frame = &c->frame_buf[0];

  614.     if (c->has_audio && c->has_video) {  /* must be a stale frame */

  615.         dv_format_frame(c, *frame);

  616. 	c->frames++;

  617. 	c->has_audio = c->has_video = 0;

  618.     }

  619.     

  620.     if (st->codec.codec_type == CODEC_TYPE_VIDEO) {

  621.         /* FIXME: we have to have more sensible approach than this one */

  622. 	if (c->has_video)

  623. 	    av_log(&st->codec, AV_LOG_ERROR, "Can't process DV frame #%d. Insufficient audio data or severe sync problem.\n", c->frames);

  624. 	    

  625.         dv_inject_video(c, data, *frame);

  626. 	c->has_video = 1;

  627. 	data_size = 0;

  628.     } 

  629.     

  630.     reqasize = 4 * dv_audio_frame_size(c->sys, c->frames);

  631.     fsize = fifo_size(&c->audio_data, c->audio_data.rptr);

  632.     if (st->codec.codec_type == CODEC_TYPE_AUDIO || (c->has_video && fsize >= reqasize)) { 

  633. 	if (fsize + data_size >= reqasize && !c->has_audio) {

  634.             if (fsize >= reqasize) {

  635. 	        fifo_read(&c->audio_data, &pcm[0], reqasize, &c->audio_data.rptr);

  636.             } else {

  637. 	        fifo_read(&c->audio_data, &pcm[0], fsize, &c->audio_data.rptr);

  638.                 memcpy(&pcm[fsize], &data[0], reqasize - fsize);

  639. 		data += reqasize - fsize;

  640. 		data_size -= reqasize - fsize;

  641. 	    }

  642. 	    dv_inject_audio(c, &pcm[0], *frame);

  643. 	    c->has_audio = 1;

  644. 	}

  645.     

  646.         /* FIXME: we have to have more sensible approach than this one */

  647.         if (fifo_size(&c->audio_data, c->audio_data.rptr) + data_size >= 100*AVCODEC_MAX_AUDIO_FRAME_SIZE)

  648. 	    av_log(&st->codec, AV_LOG_ERROR, "Can't process DV frame #%d. Insufficient video data or severe sync problem.\n", c->frames);

  649. 	fifo_write(&c->audio_data, (uint8_t *)data, data_size, &c->audio_data.wptr);

  650.     }

  651. 

  652.     return (c->has_audio && c->has_video) ? c->sys->frame_size : 0;

  653. }

  654. 

  655. DVMuxContext* dv_init_mux(AVFormatContext* s)

  656. {

  657.     DVMuxContext *c;

  658.     AVStream *vst;

  659.     AVStream *ast;

  660. 

  661.     c = av_mallocz(sizeof(DVMuxContext));

  662.     if (!c)

  663.         return NULL;

  664. 

  665.     if (s->nb_streams != 2)

  666.         goto bail_out;

  667. 

  668.     /* We have to sort out where audio and where video stream is */

  669.     if (s->streams[0]->codec.codec_type == CODEC_TYPE_VIDEO &&

  670.         s->streams[1]->codec.codec_type == CODEC_TYPE_AUDIO) {

  671.        vst = s->streams[0];

  672.        ast = s->streams[1];

  673.     }

  674.     else if (s->streams[1]->codec.codec_type == CODEC_TYPE_VIDEO &&

  675.              s->streams[0]->codec.codec_type == CODEC_TYPE_AUDIO) {

  676.            vst = s->streams[1];

  677.            ast = s->streams[0];

  678.     } else

  679.         goto bail_out;

  680.   

  681.     /* Some checks -- DV format is very picky about its incoming streams */

  682.     if (vst->codec.codec_id != CODEC_ID_DVVIDEO ||

  683. 	ast->codec.codec_id != CODEC_ID_PCM_S16LE)

  684.        goto bail_out;

  685.     if (ast->codec.sample_rate != 48000 ||

  686. 	ast->codec.channels != 2)

  687.        goto bail_out;

  688. 

  689.     c->sys = dv_codec_profile(&vst->codec);

  690.     if (!c->sys)

  691. 	goto bail_out;

  692.     

  693.     /* Ok, everything seems to be in working order */

  694.     c->frames = 0;

  695.     c->has_audio = c->has_video = 0;

  696.     c->start_time = (time_t)s->timestamp;

  697.     c->aspect = 0; /* 4:3 is the default */

  698.     if ((int)(av_q2d(vst->codec.sample_aspect_ratio) * vst->codec.width / vst->codec.height * 10) == 17) /* 16:9 */ 

  699.         c->aspect = 0x07;

  700. 

  701.     if (fifo_init(&c->audio_data, 100*AVCODEC_MAX_AUDIO_FRAME_SIZE) < 0)

  702.         goto bail_out;

  703. 

  704.     dv_format_frame(c, &c->frame_buf[0]);

  705. 

  706.     return c;

  707.     

  708. bail_out:

  709.     av_free(c);

  710.     return NULL;

  711. }

  712. 

  713. void dv_delete_mux(DVMuxContext *c)

  714. {    

  715.     fifo_free(&c->audio_data);

  716. }

  717. 

  718. DVDemuxContext* dv_init_demux(AVFormatContext *s)

  719. {

  720.     DVDemuxContext *c;

  721. 

  722.     c = av_mallocz(sizeof(DVDemuxContext));

  723.     if (!c)

  724.         return NULL;

  725. 

  726.     c->vst = av_new_stream(s, 0);

  727.     c->ast[0] = av_new_stream(s, 0);

  728.     if (!c->vst || !c->ast[0])

  729.         goto fail;

  730.     av_set_pts_info(c->vst, 64, 1, 30000);

  731.     av_set_pts_info(c->ast[0], 64, 1, 30000);

  732. 

  733.     c->fctx = s;

  734.     c->ast[1] = NULL;

  735.     c->ach = 0;

  736.     c->frames = 0;

  737.     c->abytes = 0;

  738.     c->audio_pkt[0].size = 0;

  739.     c->audio_pkt[1].size = 0;

  740.     

  741.     c->vst->codec.codec_type = CODEC_TYPE_VIDEO;

  742.     c->vst->codec.codec_id = CODEC_ID_DVVIDEO;

  743.     c->vst->codec.bit_rate = 25000000;

  744.     c->vst->start_time = 0;

  745.     

  746.     c->ast[0]->codec.codec_type = CODEC_TYPE_AUDIO;

  747.     c->ast[0]->codec.codec_id = CODEC_ID_PCM_S16LE;

  748.     c->ast[0]->codec.sample_rate = 48000;

  749.     c->ast[0]->codec.channels = 2;

  750.     c->ast[0]->start_time = 0;

  751.     

  752.     return c;

  753.     

  754. fail:

  755.     if (c->vst)

  756.         av_free(c->vst);

  757.     if (c->ast[0])

  758.         av_free(c->ast[0]);

  759.     av_free(c);

  760.     return NULL;

  761. }

  762. 

  763. static void __destruct_pkt(struct AVPacket *pkt)

  764. {

  765.     pkt->data = NULL; pkt->size = 0;

  766.     return;

  767. }

  768. 

  769. int dv_get_packet(DVDemuxContext *c, AVPacket *pkt)

  770. {

  771.     int size = -1;

  772.     int i;

  773. 

  774.     for (i=0; i<c->ach; i++) {

  775.        if (c->ast[i] && c->audio_pkt[i].size) {

  776.            *pkt = c->audio_pkt[i];

  777. 	   c->audio_pkt[i].size = 0;

  778. 	   size = pkt->size;

  779. 	   break;

  780.        }

  781.     }

  782. 

  783.     return size;

  784. }

  785. 

  786. int dv_produce_packet(DVDemuxContext *c, AVPacket *pkt, 

  787.                       uint8_t* buf, int buf_size)

  788. {

  789.     int size, i;

  790.     const DVprofile* sys = dv_frame_profile(buf);

  791.    

  792.     if (buf_size < 4 || buf_size < sys->frame_size)

  793.         return -1;   /* Broken frame, or not enough data */

  794. 

  795.     /* Queueing audio packet */

  796.     /* FIXME: in case of no audio/bad audio we have to do something */

  797.     size = dv_extract_audio_info(c, buf);

  798.     c->audio_pkt[0].data = c->audio_pkt[1].data = NULL;

  799.     for (i=0; i<c->ach; i++) {

  800.        if (av_new_packet(&c->audio_pkt[i], size) < 0)

  801.            return AVERROR_NOMEM;

  802.        c->audio_pkt[i].stream_index = c->ast[i]->index;

  803.        c->audio_pkt[i].pts = c->abytes * 30000*8 / c->ast[i]->codec.bit_rate;

  804.        c->audio_pkt[i].flags |= PKT_FLAG_KEY;

  805.     }

  806.     dv_extract_audio(buf, c->audio_pkt[0].data, c->audio_pkt[1].data);

  807.     c->abytes += size;

  808.     

  809.     /* Now it's time to return video packet */

  810.     size = dv_extract_video_info(c, buf);

  811.     av_init_packet(pkt);

  812.     pkt->destruct = __destruct_pkt;

  813.     pkt->data     = buf;

  814.     pkt->size     = size; 

  815.     pkt->flags   |= PKT_FLAG_KEY;

  816.     pkt->stream_index = c->vst->id;

  817.     pkt->pts      = c->frames * sys->frame_rate_base * (30000/sys->frame_rate);

  818.     

  819.     c->frames++;

  820. 

  821.     return size;

  822. }

  823.                            

  824. int64_t dv_frame_offset(DVDemuxContext *c, int64_t timestamp)

  825. {

  826.     const DVprofile* sys;

  827.     int64_t frame_number, offset;

  828.     

  829.     // FIXME: sys may be wrong if last dv_read_packet() failed (buffer is junk)

  830.     sys = dv_codec_profile(&c->vst->codec);

  831. 

  832.     // timestamp was scaled by time_base/AV_BASE_RATE by av_seek_frame()

  833.     frame_number = (timestamp * sys->frame_rate) / 

  834.                    ((int64_t) 30000 * sys->frame_rate_base);

  835. 

  836.     // offset must be a multiple of frame_size else dv_read_packet() will fail

  837.     offset = (int64_t) sys->frame_size * frame_number;

  838. 

  839.     return offset;

  840. }

  841. 

  842. /************************************************************

  843.  * Implementation of the easiest DV storage of all -- raw DV.

  844.  ************************************************************/

  845.  

  846. typedef struct RawDVContext {

  847.     uint8_t         buf[144000];

  848.     DVDemuxContext* dv_demux;

  849. } RawDVContext;

  850. 

  851. static int dv_read_header(AVFormatContext *s,

  852.                           AVFormatParameters *ap)

  853. {

  854.     RawDVContext *c = s->priv_data;

  855.     const DVprofile* sys;

  856.     c->dv_demux = dv_init_demux(s);

  857.     if (!c->dv_demux)

  858.         return -1;

  859.    

  860.     if (get_buffer(&s->pb, c->buf, 4) <= 0 || url_fseek(&s->pb, -4, SEEK_CUR) < 0)

  861.         return AVERROR_IO;

  862. 

  863.     sys = dv_frame_profile(c->buf);

  864.     s->bit_rate = av_rescale(sys->frame_size * 8, sys->frame_rate, sys->frame_rate_base);

  865.    

  866.     return 0;

  867. }

  868. 

  869. 

  870. static int dv_read_packet(AVFormatContext *s, AVPacket *pkt)

  871. {

  872.     int size;

  873.     RawDVContext *c = s->priv_data; 

  874.   

  875.     size = dv_get_packet(c->dv_demux, pkt);

  876.     

  877.     if (size < 0) {

  878.         if (get_buffer(&s->pb, c->buf, 4) <= 0) 

  879.             return AVERROR_IO;

  880.     

  881.         size = dv_frame_profile(c->buf)->frame_size;

  882.         if (get_buffer(&s->pb, c->buf + 4, size - 4) <= 0)

  883. 	    return AVERROR_IO;

  884. 

  885. 	size = dv_produce_packet(c->dv_demux, pkt, c->buf, size);

  886.     } 

  887.     

  888.     return size;

  889. }

  890. 

  891. static int dv_read_seek(AVFormatContext *s, int stream_index, int64_t timestamp)

  892. {

  893.     RawDVContext *c = s->priv_data;

  894. 

  895.     return url_fseek(&s->pb, dv_frame_offset(c->dv_demux, timestamp), SEEK_SET);

  896. }

  897. 

  898. static int dv_read_close(AVFormatContext *s)

  899. {

  900.     RawDVContext *c = s->priv_data;

  901.     av_free(c->dv_demux);

  902.     return 0;

  903. }

  904. 

  905. static int dv_write_header(AVFormatContext *s)

  906. {

  907.     s->priv_data = dv_init_mux(s);

  908.     if (!s->priv_data) {

  909.         av_log(s, AV_LOG_ERROR, "Can't initialize DV format!\n"

  910. 		    "Make sure that you supply exactly two streams:\n"

  911. 		    "     video: 25fps or 29.97fps, audio: 2ch/48Khz/PCM\n");

  912. 	return -1;

  913.     }

  914.     return 0;

  915. }

  916. 

  917. static int dv_write_packet(struct AVFormatContext *s, AVPacket *pkt)

  918. {

  919.     uint8_t* frame;

  920.     int fsize;

  921.    

  922.     fsize = dv_assemble_frame((DVMuxContext *)s->priv_data, s->streams[pkt->stream_index],

  923.                               pkt->data, pkt->size, &frame);

  924.     if (fsize > 0) {

  925.         put_buffer(&s->pb, frame, fsize); 

  926.         put_flush_packet(&s->pb);

  927.     } 

  928.     return 0;

  929. }

  930. 

  931. /* 

  932.  * We might end up with some extra A/V data without matching counterpart.

  933.  * E.g. video data without enough audio to write the complete frame.

  934.  * Currently we simply drop the last frame. I don't know whether this 

  935.  * is the best strategy of all

  936.  */

  937. static int dv_write_trailer(struct AVFormatContext *s)

  938. {

  939.     dv_delete_mux((DVMuxContext *)s->priv_data);

  940.     return 0;

  941. }

  942. 

  943. static AVInputFormat dv_iformat = {

  944.     "dv",

  945.     "DV video format",

  946.     sizeof(RawDVContext),

  947.     NULL,

  948.     dv_read_header,

  949.     dv_read_packet,

  950.     dv_read_close,

  951.     dv_read_seek,

  952.     .extensions = "dv,dif",

  953. };

  954. 

  955. static AVOutputFormat dv_oformat = {

  956.     "dv",

  957.     "DV video format",

  958.     NULL,

  959.     "dv",

  960.     sizeof(DVMuxContext),

  961.     CODEC_ID_PCM_S16LE,

  962.     CODEC_ID_DVVIDEO,

  963.     dv_write_header,

  964.     dv_write_packet,

  965.     dv_write_trailer,

  966. };

  967. 

  968. int ff_dv_init(void)

  969. {

  970.     av_register_input_format(&dv_iformat);

  971.     av_register_output_format(&dv_oformat);

  972.     return 0;

  973. }