Method and device for synchronizing the displacements of two moving bodies

Claim 1

A method for recording and reproducing in synchronism pictures and sounds of a filmed scene, said method comprising a first step which consists in simultaneously recording the pictures and sounds, respectively, on a photographic film and on a magnetic tape, each being driven independently of the other by independent drive means, while generating recurrent pulses, in synchronism with the driving of said film, and recording said pulses on a separate track of said magnetic tape, and thereafter developing said film, said tape being provided with a blank sound track - a second step which consists in projecting the scenes of the developed film and playing back said tape for simultaneously reproducing the pictures and the sound characteristic of said scene in proximate time correspondence, generating control pulses in synchronism with said film drive while reading said recurrent pulses recorded on said tape, counting said control pulses and recorded recurrent pulses and automatically controlling one of the drive means for adjusting the respective counts of said control pulses and recorded pulses so as to be substantially equal whereby to improve the picture synchronization with sound, ideal synchronization of the picture and sound being achieved by selectively and momentarily manually discontinuing either of said counts, - a third step which consists in reversely driving said film and tape to the beginning of said scene while preserving said ideal synchronization by counting said control pulses and recorded pulses and automatically controlling one of said drive means as in said second step, - and a fourth step which consists in again driving said film and tape in the normal forward direction for simultaneously reproducing said pictures and said sound from the beginning to the end of said scene while preserving said ideal synchronization as in said third step, and transferring the sound recorded on the tape in the first step to the blank sound track on the tape.

Claim 2

A method for recording and reproducing in synchronism pictures and sounds of a filmed scene, said method comprising a first step which consists in simultaneously recording the pictures and sounds, respectively, on a photographic film and on a magnetic tape, each being driven independently of the other by independent drive means, while generating recurrent pulses, in synchronism with the driving of said film, and recording said pulses on a separate track of said magnetic tape, and thereafter developing said film, said tape being provided with a blank sound track - a second step which consists in projecting the scenes of the developed film and playing back said tape for simultaneously reproducing the pictures and the sound characteristic of said scene in proximate time correspondence, generating control pulses in synchronism with said film drive while reading said recurrent pulses recorded on said tape, counting said control pulses and recorded recurrent pulses and automatically controlling one of the drive means for adjusting the respective counts of said control pulses and recorded pulses so as to be substantially equal whereby to improve the picture synchronization with sound, ideal synchronization of the picture and sound being achieved by selectively and momentarily manually discontinuing either of said counts, - a third step which consists in reversely driving said film and tape to the beginning of said scene while preserving said ideal synchronization by counting said control pulses and recorded pulses and automatically controlling one of said drive means as in said second step, - and a fourth step which consists in again driving said film and tape in the normal forward direction for simultaneously reproducing said pictures and said sound from the beginning to the end of said scene while preserving said ideal synchronization as in said third step, and transferring the sound recorded on the tape in the first step to the blank sound track on the tape.

Claim 4

A device for recording and reproducing in synchronism pictures and sound corresponding to a filmed scene, comprising - a camera for taking pictures adapted for development as a photographic film, a projector for reproducing said pictures on said film, said camera and projector each being provided with respective drive means for driving said film at a predetermined speed and with associated generating means for respectively generating recurrent pulses and control pulses in synchronism with the driving of said film, - a sound recorder for recording sound associated with said scene on a magnetic tape and for playing back said sound recorded on said tape, said recorder being provided with means for driving said tape at a controllable speed and with means for recording said recurrent pulses on a separate track of the said tape and then playing back said recorded pulses, - first coupling means for connecting said camera to said recorder when said camera is taking pictures and for recording said sound associated with said scene, said coupling means being operative for transmitting said recurrent pulses from said generating means to said recording means, - and second coupling means for connecting said projector to said sound recorder, when projecting said pictures, for playing back said sound, said second coupling means including counting means connected on the one hand to said generating means of said projector for counting said control pulses and on the other hand to said play back means of said recorder for counting said recorded pulses, said counting means supplying an output signal representative of the difference between the respective counts of said control pulses and recorded pulses, automatic control means operatively coupled to said counting means and to said driving means of said recorder for changing in response to said output signal the driving speed of said tape to reduce said difference between said counts, and thereby to improve the synchronization betweEn said sound and said pictures, manually operated control means operatively associated with said counting means for selectively and momentarily discontinuing the count of one of said control and recorded pulses to perfect said synchronization, said means for counting said control pulses and recorded pulses including second circuit means operative for converting said pulses into identical calibrated pulses having a characteristic signal indicating its origin, and third circuit means including a single counter having a single data input receiving said calibrated pulses and also a pair of control inputs respectively receiving said characteristic signals indicative of either pulse origin, whereby said counter counts each of said calibrated.

Claim 5

A device for recording and reproducing in synchronism pictures and sound corresponding to a filmed scene, comprising - a camera for taking pictures adapted for development as a photographic film, a projector for reproducing said pictures on said film, said camera and projector each being provided with respective drive means for driving said film at a predetermined speed and with associated generating means for respectively generating recurrent pulses and control pulses in synchronism with the driving of said film, - a sound recorder for recording sound associated with said scene on a magnetic tape and for playing back said sound recorded on said tape, said recorder being provided with means for driving said tape at a controllable speed and with means for recording said recurrent pulses on a separate track of the said tape and then playing back said recorded pulses, - first coupling means for connecting said camera to said recorder when said camera is taking pictures and for recording said sound associated with said scene, said coupling means being operative for transmitting said recurrent pulses from said generating means to said recording means, - and second coupling means for connecting said projector to said sound recorder, when projecting said pictures, for playing back said sound, said second coupling means including counting means connected on the one hand to said generating means of said projector for counting said control pulses and on the other hand to said play back means of said recorder for counting said recorded pulses, said counting means supplying an output signal representative of the difference between the respective counts of said control pulses and recorded pulses, automatic control means operatively coupled to said counting means and to said driving means of said recorder for changing in response to said output signal the driving speed of said tape to reduce said difference between said counts, and thereby to improve the synchronization betweEn said sound and said pictures, manually operated control means operatively associated with said counting means for selectively and momentarily discontinuing the count of one of said control and recorded pulses to perfect said synchronization, said means for counting said control pulses and recorded pulses including second circuit means operative for converting said pulses into identical calibrated pulses having a characteristic signal indicating its origin, and third circuit means including a single counter having a single data input receiving said calibrated pulses and also a pair of control inputs respectively receiving said characteristic signals indicative of either pulse origin, whereby said counter counts each of said calibrated.