Introduction Of Timecode
While playing a video there should be accurate lips synchronization for better user experience. A little bit variation in lips synchronization affect the users too much. A video editor synchronizes audio with video in editing room when both of these two things were recorded from two different device.
Sometimes in headend we gets bad lips synchronization at the output of a encoder. Then sometimes this problem get resolved just by hard booting the encoder. But after sometime it comes back again there may be many reasons behind this for this kind of behavior of a encoder. Which result very bad user experience.
Thus while playing a video lips synchronization plays a very important role. So today in this article we are going to cover What Is Timecode ? and How Does It Works ?
What Is Timecode
Timecode is the 8 digit numeric number allotted to each frame of video. In this 8 digit numeric numbers first two digit represents Hours, Second two digit represents Minutes, third two digits represents Seconds and last two digit represents Frames.
As shown above in the figure 10 represents number of hours, 18 represents minutes, 45 represents seconds and 24 represents number of frames.
Where sometime first two digits are used to represent the days. In the above case there will be 10 days. While first two digits sometimes also represented as tape number. So in this case 18 minutes 24 seconds and 24 frames video will be in tape number 10.
This clock runs on Military Timing of 24 hours.
Working Of Timecode
SMPTE stands for Society Of Motion Picture and Television Engineers. SMPTE is a Standard for Timecode.
At large media industry where video and audio files are recorded separately by using two different devices. After the recording of audio and video they needs to do the editing of the video for final output of video.
So in the editing room both part of this content audio and video is synchronized together to produce final output. Professional software are used to do this. So at the time of editing this Timecode is used from video editor person.
So this is done to establish a synchronization between two different files audio and video by using professional software. Timecode are now also used in audio encoding too.
So timecode is a kind of stamp on every frame of video which makes easy for us to do the editing. Where we can identify a particular frame of video. Thus video editor will easily track a single frame of a video and can do editing in that particular frame. So a video editor can manipulate the video frames very easily just by tracking it with timecode.
At the time of recording a video al the recording devices have its own time in it. But that time do not suit to system. So a external timecode generator is used to manage this. So this external timecode generator is connected to each and every recording device.
External Timecode Generator is connected in Master and Slave format. Which means slave recording device also synchronize with master device to manage the timecode. The slave recording device is connected with master device in wireless manner.
Now at the time of recording if slave recording device camera goes out of range for master device. Then at that period of time the slave device will use its own internal time clock. After sometime if slave device gets again in range of master device then again it synchronizes with master device.
There are two types of SMPTE Time Code available named as ,
(1) LTC
(2) VITC
Where LTC Stands for Longitudinal Time Code. While VITC stands for Vertical Interval Time Code.
Conclusion
Timecodes are the 8 digit numeric format allotted to each frame in video for frame tracking purpose. So it is kind of identification of every frame of video. It is widely used where more than one different recording devices are used. External timecode generators are widely used in large scale recording system to manage the timecode.
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