172:
294:. Syntonized video signals will be precisely frequency-locked, but because of delays caused by the unequal transmission path lengths, the synchronized signals will exhibit differing phases at various points in the television system. Modern video equipment such as production switchers that have multiple video inputs often include a variable delay on each input to compensate for the phase differences and time all the input signals to precise phase coincidence.
70:
29:
340:(production switcher)), or in a wider facility where all the video sources are locked to a single synchronizing pulse generator (e.g., a fast-paced sporting event featuring multiple cameras and recording devices). Generator locking can also be used to ensure that multiple CRT monitors that appear in a movie are flicker-free. Generator locking is also used to synchronize two cameras for
378:
pulse is a signal that initially goes from 0 volts DC to a negative voltage, then a positive voltage, before returning to zero volts DC again. The voltage excursions are typically 300 mV either side of zero volts, and the duration each of the two excursions is the same as a particular number of
297:
Where two or more video signals are combined or being switched between, the horizontal and vertical timing of the picture sources should be coincident with each other. If they are not, the picture will appear to jump when switching between the sources whilst the display device re-adjusts the
373:
Although some high-definition broadcast systems may use a standard-definition reference signal as a generator-locking reference signal, the use of tri-level synchronising pulses directly related to the frame and line rate is increasing within HD systems. A
257:) is used to synchronize other picture sources together. The aim in video applications is to ensure the coincidence of signals in time at a combining or switching point. When video instruments are synchronized in this way, they are said to be
399:
or optical fibre cable, the analog generator-locking signal is used to lock the camera control unit, which in turn locks the camera head by means of information carried within a data channel transmitted along the cable. If the camera is an
369:
is usually given to such a signal. A composite colour video signal inherently carries the same reference signals and can be used as a generator-locking signal, albeit at the risk of being disturbed by out-of-specification picture signals.
277:
347:
In broadcast systems, an analog generator-lock signal usually consists of vertical and horizontal synchronizing pulses together with chrominance phase reference in the form of
404:-type camera, one without a triax/fibre connection or without a dockable head, the generator-locking signal is carried through a separate cable from the video.
415:
is a picture-source synchronizing system using audio tone signals to describe the timing discrepancies between composite video signals, while
316:
of each source being combined or switched should also be coincident. This is to avoid changes in colour hue and/or saturation during a
457:
272:
554:
134:
233:
215:
193:
153:
56:
503:
186:
106:
564:
559:
113:
91:
522:
120:
432:
420:
401:
392:
253:) is a common technique where the video output of one source (or a specific reference signal from a
102:
549:
180:
87:
42:
351:. No picture information is usually carried to avoid disturbing the timing signals, and the name
80:
197:
8:
437:
395:
have dedicated generator-locking ports on the camera. If the camera is tethered with a
388:
329:
328:
Generator locking can be used to synchronize as few as two isolated sources (e.g., a
127:
461:
254:
290:
Video signals generated and output by generator-locked instruments are said to be
357:
317:
396:
375:
291:
543:
482:
306:
268:
337:
48:
507:
341:
310:
299:
348:
313:
333:
69:
17:
94:. Unsourced material may be challenged and removed.
532:(58): 11–12 – via americanradiohistory.com.
541:
57:Learn how and when to remove these messages
460:. MicroImage Video Systems. Archived from
523:"The Genlock for Improved TV Programming"
419:uses digital information conveyed in the
234:Learn how and when to remove this message
216:Learn how and when to remove this message
154:Learn how and when to remove this message
179:This article includes a list of general
542:
305:Where composite video is in use, the
285:
165:
92:adding citations to reliable sources
63:
22:
520:
13:
185:it lacks sufficient corresponding
14:
576:
521:Roe, John H. (March–April 1950).
38:This article has multiple issues.
16:For the animated web series, see
506:. ATIS Committee. Archived from
302:to correctly reframe the image.
170:
68:
27:
79:needs additional citations for
46:or discuss these issues on the
514:
496:
475:
450:
382:
1:
443:
423:of a composite video signal.
7:
426:
407:
298:horizontal and/or vertical
10:
581:
433:Frame synchronizer (video)
421:vertical blanking interval
393:professional video cameras
273:Excessive citations inline
15:
555:Film and video technology
379:digital picture samples.
458:"An Overview of Genlock"
323:
278:considered for deletion
200:more precise citations.
565:Television terminology
560:Broadcast engineering
88:improve this article
438:Time base corrector
530:RCA Broadcast News
336:machine feeding a
389:television studio
344:video recording.
330:television camera
320:between sources.
286:Possible problems
251:generator locking
244:
243:
236:
226:
225:
218:
164:
163:
156:
138:
61:
572:
534:
533:
527:
518:
512:
511:
500:
494:
493:
491:
490:
479:
473:
472:
470:
469:
454:
281:
259:generator-locked
255:signal generator
239:
232:
221:
214:
210:
207:
201:
196:this article by
187:inline citations
174:
173:
166:
159:
152:
148:
145:
139:
137:
96:
72:
64:
53:
31:
30:
23:
580:
579:
575:
574:
573:
571:
570:
569:
550:Synchronization
540:
539:
538:
537:
525:
519:
515:
502:
501:
497:
488:
486:
481:
480:
476:
467:
465:
456:
455:
451:
446:
429:
410:
385:
358:black and burst
342:Stereoscopic 3D
326:
288:
266:
240:
229:
228:
227:
222:
211:
205:
202:
192:Please help to
191:
175:
171:
160:
149:
143:
140:
97:
95:
85:
73:
32:
28:
21:
12:
11:
5:
578:
568:
567:
562:
557:
552:
536:
535:
513:
510:on 2007-12-27.
495:
474:
448:
447:
445:
442:
441:
440:
435:
428:
425:
409:
406:
397:triaxial cable
384:
381:
376:tri-level sync
325:
322:
287:
284:
242:
241:
224:
223:
178:
176:
169:
162:
161:
76:
74:
67:
62:
36:
35:
33:
26:
9:
6:
4:
3:
2:
577:
566:
563:
561:
558:
556:
553:
551:
548:
547:
545:
531:
524:
517:
509:
505:
499:
484:
478:
464:on 2015-04-03
463:
459:
453:
449:
439:
436:
434:
431:
430:
424:
422:
418:
414:
405:
403:
398:
394:
390:
380:
377:
371:
368:
364:
360:
359:
354:
350:
345:
343:
339:
335:
331:
321:
319:
315:
312:
308:
303:
301:
295:
293:
283:
279:
275:
274:
270:
264:
260:
256:
252:
248:
238:
235:
220:
217:
209:
206:February 2024
199:
195:
189:
188:
182:
177:
168:
167:
158:
155:
147:
136:
133:
129:
126:
122:
119:
115:
112:
108:
105: –
104:
100:
99:Find sources:
93:
89:
83:
82:
77:This article
75:
71:
66:
65:
60:
58:
51:
50:
45:
44:
39:
34:
25:
24:
19:
529:
516:
508:the original
498:
487:. Retrieved
477:
466:. Retrieved
462:the original
452:
416:
412:
411:
386:
372:
366:
362:
356:
352:
346:
338:vision mixer
327:
304:
296:
289:
271:
262:
258:
250:
246:
245:
230:
212:
203:
184:
150:
141:
131:
124:
117:
110:
98:
86:Please help
81:verification
78:
54:
47:
41:
40:Please help
37:
383:Connections
367:black burst
363:color black
311:chrominance
198:introducing
544:Categories
489:2012-02-23
468:2014-03-25
444:References
349:colorburst
318:transition
314:subcarrier
292:syntonized
181:references
114:newspapers
43:improve it
504:"genlock"
483:"Genlock"
353:reference
334:videotape
276:is being
263:genlocked
144:June 2011
103:"Genlock"
49:talk page
485:. NVIDIA
427:See also
408:Variants
269:template
18:Gen:Lock
417:Icelock
413:Natlock
309:of the
282:
247:Genlock
194:improve
128:scholar
332:and a
183:, but
130:
123:
116:
109:
101:
526:(PDF)
387:Most
365:, or
324:Scope
307:phase
267:‹The
261:, or
135:JSTOR
121:books
391:and
300:scan
107:news
402:ENG
90:by
546::
528:.
361:,
355:,
280:.›
52:.
492:.
471:.
265:.
249:(
237:)
231:(
219:)
213:(
208:)
204:(
190:.
157:)
151:(
146:)
142:(
132:·
125:·
118:·
111:·
84:.
59:)
55:(
20:.
Text is available under the Creative Commons Attribution-ShareAlike License. Additional terms may apply.
