libltc  1.3.0
Linear/Logitudinal Time Code (LTC) Library
ltc.h
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1 
36 #ifndef LTC_H
37 #define LTC_H 1
38 
39 #ifdef __cplusplus
40 extern "C" {
41 #endif
42 
43 #if defined _WIN32 && !defined(__LITTLE_ENDIAN__)
44 #define __LITTLE_ENDIAN__
45 #endif
46 
47 #ifdef __BIG_ENDIAN__
48 # define LTC_BIG_ENDIAN
49 #elif defined _BIG_ENDIAN
50 # define LTC_BIG_ENDIAN
51 #elif defined __BYTE_ORDER__
52 # if __BYTE_ORDER__ == __ORDER_BIG_ENDIAN__
53 # define LTC_BIG_ENDIAN
54 # endif
55 #elif !defined __LITTLE_ENDIAN__
56 # include <endian.h> // machine/endian.h
57 # if (defined __BYTE_ORDER__ && defined __ORDER_BIG_ENDIAN__ && __BYTE_ORDER__ == __ORDER_BIG_ENDIAN__)
58 # define LTC_BIG_ENDIAN
59 # endif
60 #endif
61 
62 #include <stddef.h> /* size_t */
63 
64 #ifndef DOXYGEN_IGNORE
65 /* libltc version */
66 #define LIBLTC_VERSION "1.3.0"
67 #define LIBLTC_VERSION_MAJOR 1
68 #define LIBLTC_VERSION_MINOR 3
69 #define LIBLTC_VERSION_MICRO 0
70 
71 /* interface revision number
72  * http://www.gnu.org/software/libtool/manual/html_node/Updating-version-info.html
73  */
74 #define LIBLTC_CUR 11
75 #define LIBLTC_REV 5
76 #define LIBLTC_AGE 0
77 #endif /* end DOXYGEN_IGNORE */
78 
82 typedef unsigned char ltcsnd_sample_t;
83 
87 typedef long long int ltc_off_t;
88 
89 #define LTC_FRAME_BIT_COUNT 80
90 
181 #if (defined LTC_BIG_ENDIAN && !defined DOXYGEN_IGNORE)
182 // Big Endian version, bytes are "upside down"
183 struct LTCFrame {
184  unsigned int user1:4;
185  unsigned int frame_units:4;
186 
187  unsigned int user2:4;
188  unsigned int col_frame:1;
189  unsigned int dfbit:1;
190  unsigned int frame_tens:2;
191 
192  unsigned int user3:4;
193  unsigned int secs_units:4;
194 
195  unsigned int user4:4;
196  unsigned int biphase_mark_phase_correction:1;
197  unsigned int secs_tens:3;
198 
199  unsigned int user5:4;
200  unsigned int mins_units:4;
201 
202  unsigned int user6:4;
203  unsigned int binary_group_flag_bit0:1;
204  unsigned int mins_tens:3;
205 
206  unsigned int user7:4;
207  unsigned int hours_units:4;
208 
209  unsigned int user8:4;
210  unsigned int binary_group_flag_bit2:1;
211  unsigned int binary_group_flag_bit1:1;
212  unsigned int hours_tens:2;
213 
214  unsigned int sync_word:16;
215 };
216 #else
217 /* Little Endian version -- and doxygen doc */
218 struct LTCFrame {
219  unsigned int frame_units:4;
220  unsigned int user1:4;
221 
222  unsigned int frame_tens:2;
223  unsigned int dfbit:1;
224  unsigned int col_frame:1;
225  unsigned int user2:4;
226 
227  unsigned int secs_units:4;
228  unsigned int user3:4;
229 
230  unsigned int secs_tens:3;
232  unsigned int user4:4;
233 
234  unsigned int mins_units:4;
235  unsigned int user5:4;
236 
237  unsigned int mins_tens:3;
238  unsigned int binary_group_flag_bit0:1;
239  unsigned int user6:4;
240 
241  unsigned int hours_units:4;
242  unsigned int user7:4;
243 
244  unsigned int hours_tens:2;
245  unsigned int binary_group_flag_bit1:1;
246  unsigned int binary_group_flag_bit2:1;
247  unsigned int user8:4;
248 
249  unsigned int sync_word:16;
250 };
251 #endif
252 
262 };
263 
270 };
271 
275 typedef struct LTCFrame LTCFrame;
276 
293 struct LTCFrameExt {
295  ltc_off_t off_start;
296  ltc_off_t off_end;
297  int reverse;
298  float biphase_tics[LTC_FRAME_BIT_COUNT];
299  ltcsnd_sample_t sample_min;
300  ltcsnd_sample_t sample_max;
301  double volume;
302 };
303 
307 typedef struct LTCFrameExt LTCFrameExt;
308 
313  char timezone[6];
314  unsigned char years;
315  unsigned char months;
316  unsigned char days;
317 
318  unsigned char hours;
319  unsigned char mins;
320  unsigned char secs;
321  unsigned char frame;
322 };
323 
328 
329 
334 typedef struct LTCDecoder LTCDecoder;
335 
340 typedef struct LTCEncoder LTCEncoder;
341 
351 void ltc_frame_to_time(SMPTETimecode* stime, LTCFrame* frame, int flags);
352 
365 void ltc_time_to_frame(LTCFrame* frame, SMPTETimecode* stime, enum LTC_TV_STANDARD standard, int flags);
366 
373 void ltc_frame_reset(LTCFrame* frame);
374 
389 int ltc_frame_increment(LTCFrame* frame, int fps, enum LTC_TV_STANDARD standard, int flags);
390 
406 int ltc_frame_decrement(LTCFrame* frame, int fps, enum LTC_TV_STANDARD standard, int flags);
407 
416 LTCDecoder * ltc_decoder_create(int apv, int queue_size);
417 
418 
424 
437  ltcsnd_sample_t *buf, size_t size,
438  ltc_off_t posinfo);
439 
449 void ltc_decoder_write_float(LTCDecoder *d, float *buf, size_t size, ltc_off_t posinfo);
450 
460 void ltc_decoder_write_s16(LTCDecoder *d, short *buf, size_t size, ltc_off_t posinfo);
461 
471 void ltc_decoder_write_u16(LTCDecoder *d, unsigned short *buf, size_t size, ltc_off_t posinfo);
472 
481 int ltc_decoder_read(LTCDecoder *d, LTCFrameExt *frame);
482 
488 
495 
496 
497 
508 LTCEncoder* ltc_encoder_create(double sample_rate, double fps, enum LTC_TV_STANDARD standard, int flags);
509 
515 
529 
541 
547 
554 
565 
573 
584 int ltc_encoder_get_buffer(LTCEncoder *e, ltcsnd_sample_t *buf);
585 
586 
595 ltcsnd_sample_t *ltc_encoder_get_bufptr(LTCEncoder *e, int *size, int flush);
596 
602 
615 
642 int ltc_encoder_reinit(LTCEncoder *e, double sample_rate, double fps, enum LTC_TV_STANDARD standard, int flags);
643 
651 
669 int ltc_encoder_set_bufsize(LTCEncoder *e, double sample_rate, double fps);
670 
687 int ltc_encoder_set_volume(LTCEncoder *e, double dBFS);
688 
705 void ltc_encoder_set_filter(LTCEncoder *e, double rise_time);
706 
729 int ltc_encoder_encode_byte(LTCEncoder *e, int byte, double speed);
730 
745 
763 void ltc_frame_set_parity(LTCFrame *frame, enum LTC_TV_STANDARD standard);
764 
775 int parse_bcg_flags(LTCFrame *f, enum LTC_TV_STANDARD standard);
776 
791 ltc_off_t ltc_frame_alignment(double samples_per_frame, enum LTC_TV_STANDARD standard);
792 
793 #ifdef __cplusplus
794 }
795 #endif
796 
797 #endif
ltc_off_t ltc_frame_alignment(double samples_per_frame, enum LTC_TV_STANDARD standard)
unsigned char secs
second 0..60
Definition: ltc.h:320
void ltc_encoder_buffer_flush(LTCEncoder *e)
int ltc_encoder_inc_timecode(LTCEncoder *e)
void ltc_frame_to_time(SMPTETimecode *stime, LTCFrame *frame, int flags)
unsigned char ltcsnd_sample_t
Definition: ltc.h:82
void ltc_encoder_set_timecode(LTCEncoder *e, SMPTETimecode *t)
int ltc_encoder_dec_timecode(LTCEncoder *e)
int reverse
if non-zero, a reverse played LTC frame was detected. Since the frame was reversed, it started at off_end and finishes as off_start (off_end > off_start). (Note: in reverse playback the (reversed) sync-word of the next/previous frame is detected, this offset is corrected).
Definition: ltc.h:297
int ltc_decoder_free(LTCDecoder *d)
int ltc_decoder_queue_length(LTCDecoder *d)
unsigned int sync_word
Definition: ltc.h:249
LTCEncoder * ltc_encoder_create(double sample_rate, double fps, enum LTC_TV_STANDARD standard, int flags)
unsigned int user8
Definition: ltc.h:247
struct LTCEncoder LTCEncoder
Definition: ltc.h:340
unsigned char months
valid months are 1..12
Definition: ltc.h:315
ltcsnd_sample_t * ltc_encoder_get_bufptr(LTCEncoder *e, int *size, int flush)
unsigned int user3
Definition: ltc.h:228
void ltc_encoder_get_timecode(LTCEncoder *e, SMPTETimecode *t)
unsigned char days
day of month 1..31
Definition: ltc.h:316
void ltc_encoder_set_filter(LTCEncoder *e, double rise_time)
LTC_BG_FLAGS
Definition: ltc.h:265
25fps
Definition: ltc.h:259
the Timecode is wall-clock aka freerun. This also sets BGF1 (unless LTC_BGF_DONT_TOUCH is given) ...
Definition: ltc.h:267
unsigned int frame_tens
SMPTE framenumber BCD tens 0..3.
Definition: ltc.h:222
unsigned int mins_tens
SMPTE minutes BCD tens 0..6.
Definition: ltc.h:237
int ltc_encoder_set_volume(LTCEncoder *e, double dBFS)
int ltc_frame_decrement(LTCFrame *frame, int fps, enum LTC_TV_STANDARD standard, int flags)
unsigned int binary_group_flag_bit1
indicate timecode is local time wall-clock, see table above - bit 58
Definition: ltc.h:245
unsigned int user4
Definition: ltc.h:232
unsigned int frame_units
SMPTE framenumber BCD unit 0..9.
Definition: ltc.h:219
#define LTC_FRAME_BIT_COUNT
Definition: ltc.h:89
unsigned int user2
Definition: ltc.h:225
void ltc_frame_reset(LTCFrame *frame)
void ltc_encoder_reset(LTCEncoder *e)
24fps
Definition: ltc.h:261
void ltc_decoder_write_s16(LTCDecoder *d, short *buf, size_t size, ltc_off_t posinfo)
unsigned char frame
sub-second frame 0..(FPS - 1)
Definition: ltc.h:321
ltc_off_t off_end
Definition: ltc.h:296
void ltc_decoder_write_u16(LTCDecoder *d, unsigned short *buf, size_t size, ltc_off_t posinfo)
30fps
Definition: ltc.h:260
void ltc_decoder_queue_flush(LTCDecoder *d)
unsigned int biphase_mark_phase_correction
see note on Bit 27 in description and ltc_frame_set_parity .
Definition: ltc.h:231
int parse_bcg_flags(LTCFrame *f, enum LTC_TV_STANDARD standard)
unsigned int col_frame
colour-frame: timecode intentionally synchronized to a colour TV field sequence
Definition: ltc.h:224
int ltc_encoder_get_buffer(LTCEncoder *e, ltcsnd_sample_t *buf)
int ltc_encoder_set_bufsize(LTCEncoder *e, double sample_rate, double fps)
int ltc_encoder_reinit(LTCEncoder *e, double sample_rate, double fps, enum LTC_TV_STANDARD standard, int flags)
unsigned int binary_group_flag_bit2
indicate user-data char encoding (or parity with 25fps), see table above - bit 59 ...
Definition: ltc.h:246
void ltc_decoder_write(LTCDecoder *d, ltcsnd_sample_t *buf, size_t size, ltc_off_t posinfo)
parity bit is left untouched when setting or in/decrementing the encoder frame-number ...
Definition: ltc.h:269
LTCFrame ltc
the actual LTC frame. see LTCFrame
Definition: ltc.h:294
Definition: ltc.h:293
void ltc_encoder_get_frame(LTCEncoder *e, LTCFrame *f)
void ltc_time_to_frame(LTCFrame *frame, SMPTETimecode *stime, enum LTC_TV_STANDARD standard, int flags)
void ltc_encoder_encode_frame(LTCEncoder *e)
void ltc_frame_set_parity(LTCFrame *frame, enum LTC_TV_STANDARD standard)
unsigned int user6
Definition: ltc.h:239
ltc_off_t off_start
Definition: ltc.h:295
unsigned char mins
minute 0..60
Definition: ltc.h:319
unsigned int dfbit
indicated drop-frame timecode
Definition: ltc.h:223
Definition: ltc.h:218
unsigned int hours_tens
SMPTE hours BCD tens 0..2.
Definition: ltc.h:244
unsigned int binary_group_flag_bit0
indicate user-data char encoding, see table above - bit 43
Definition: ltc.h:238
int ltc_frame_increment(LTCFrame *frame, int fps, enum LTC_TV_STANDARD standard, int flags)
encoder init or re-init does not touch the BGF bits (initial values after initialization is zero) ...
Definition: ltc.h:268
struct LTCDecoder LTCDecoder
Definition: ltc.h:334
int ltc_encoder_encode_byte(LTCEncoder *e, int byte, double speed)
ltcsnd_sample_t sample_max
the maximum input sample signal for this frame (0..255)
Definition: ltc.h:300
Definition: ltc.h:312
unsigned int mins_units
SMPTE minutes BCD unit 0..9.
Definition: ltc.h:234
double volume
the volume of the input signal in dbFS
Definition: ltc.h:301
unsigned char years
LTC-date uses 2-digit year 00.99.
Definition: ltc.h:314
void ltc_decoder_write_float(LTCDecoder *d, float *buf, size_t size, ltc_off_t posinfo)
unsigned int user1
Definition: ltc.h:220
void ltc_encoder_free(LTCEncoder *e)
unsigned int secs_units
SMPTE seconds BCD unit 0..9.
Definition: ltc.h:227
LTCFrame <> SMPTETimecode converter and LTCFrame increment/decrement use date, also set BGF2 to &#39;1&#39; w...
Definition: ltc.h:266
unsigned int hours_units
SMPTE hours BCD unit 0..9.
Definition: ltc.h:241
unsigned int secs_tens
SMPTE seconds BCD tens 0..6.
Definition: ltc.h:230
LTCDecoder * ltc_decoder_create(int apv, int queue_size)
30fps
Definition: ltc.h:258
unsigned char hours
hour 0..23
Definition: ltc.h:318
void ltc_encoder_set_frame(LTCEncoder *e, LTCFrame *f)
ltcsnd_sample_t sample_min
the minimum input sample signal for this frame (0..255)
Definition: ltc.h:299
LTC_TV_STANDARD
Definition: ltc.h:257
unsigned int user5
Definition: ltc.h:235
int ltc_decoder_read(LTCDecoder *d, LTCFrameExt *frame)
long long int ltc_off_t
Definition: ltc.h:87
size_t ltc_encoder_get_buffersize(LTCEncoder *e)
unsigned int user7
Definition: ltc.h:242