Time code and word clock
Download
1 / 16

Time Code and Word Clock - PowerPoint PPT Presentation

Time Code and Word Clock Syncing Audio with Video and MIDI And syncing digital devices What is Time Code? It is a way of SYNCRONIZATION It allows different kinds of devices to communicate and sync together This can be useful with: Audio for Video MIDI systems Various digital devices

loader
I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.
capcha

Download Presentationdownload

Time Code and Word Clock

An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.


- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -

Presentation Transcript


Time code and word clock l.jpg

Time Code and Word Clock

Syncing Audio with Video and MIDI

And syncing digital devices


What is time code l.jpg

What is Time Code?

  • It is a way of SYNCRONIZATION

  • It allows different kinds of devices to communicate and sync together

  • This can be useful with:

    • Audio for Video

    • MIDI systems

    • Various digital devices


Smpte time code l.jpg

SMPTE Time Code

  • When audio is added to video, they need a way to be perfectly in SYNC

  • VIDEO is made up of individual frames

  • DIGITAL AUDIO is made up of SAMPLES


What is smpte l.jpg

What is SMPTE?

  • The Society of Motion Picture and Television Engineers

  • They decided on a UNIVERSAL standard.


Frame rates l.jpg

Frame Rates

  • The time codes depend on the frame rate of the video

  • It is usually one of the following:

    • 24 FPS (Common for film)

    • 25 FPS (PAL European format)

    • 29.97 FPS (NTSC American)

    • 30 FPS (HDTV)


Audio video communication l.jpg

Audio/Video Communication

  • The audio and video streams are generally produces from different devices

  • Using a universal SMPTE format allows for the audio to stay perfectly in place with the frames

  • For example:

    • Take 24 video FPS and 48k audio

    • That’s 2,000 audio samples for every frame of video!


Telecine and 3 2 pulldown l.jpg

Telecine and 3:2 Pulldown

  • TELECINE is the process of converting motion picture film to a video format

  • 3:2 pulldown makes 24 FPS film look proper on a TV broadcasting NTSC 29.97 FPS.

  • Luckily, audio is not affected by this process


Midi time code mtc l.jpg

MIDI Time Code (MTC)

  • Remember that MIDI is simply data information

  • MTC is simply another form of syncing audio and video

  • These are called ‘Quarter-frame’ messages


Word clock l.jpg

Word Clock

  • Word Clock is DIFFERENT than timecode

  • It is for syncing digital devices to avoid data errors

  • This can also be useful with:

    • Tape machines

    • CD Players

    • Multiple digital devices


Master word clock l.jpg

Master Word Clock

  • These devices are used to sync it all perfectly

    • Antelope

    • Drawmer

    • Lucid

    • Digidesign


Jitter l.jpg

Jitter

  • Jitter is distortion of high-frequency signal

  • It is caused during transmission between digital devices

  • This is often caused by clock errors and can be avoided by:

    • Using a Master Word Clock

    • Using quality A/D converters with Jitter reduction

    • Jitter reduction built in to digital units


Syncing in the modern studio l.jpg

Syncing in the modern studio

  • Syncing is often now done “In the Box”

  • Software is designed to sync internally

  • Modern digital devices have technology to sync properly and avoid jitter


Surround sound l.jpg

Surround Sound

  • Most common format is 5.1

  • 7.1 is also supported on Blu-Ray

  • The ‘.1’ refers to the LFE channel (Low-Frequency emmissions)

  • Generally, this is a crossover for the subwoofer, incorporated by the engineers


Uncompressed audio for video l.jpg

Uncompressed Audio for Video

  • PCM: Pulse Code Modulation

  • This is a completely uncompressed file, just like we would save from Pro Tools

  • Blu-Ray TrueHD: Linear PCM 8 Channels fully uncompressed! Wow.


Dts and dolby digital l.jpg

DTS and Dolby Digital

  • Support surround sound, but are compressed audio formats

  • They are considered a ‘CODEC’ almost always found on DVD discs

  • About 640 kbps compression rate


Some other formats l.jpg

Some Other Formats

  • DVD Audio

    • Up to 192k stereo, 96k full surround

    • 24-bit audio

  • SACD

    • Sampling rate up to 2822 khz! (CD is 44.1)

    • 120dB Dynamic Range (CD is 96)

    • Nearly 8GB capacity


ad
  • Login