Despatch to Broadcast


The final step in the TV commercials production process, this is simply getting your TVC on air.

Once your TVC has received its CAD classification and CAD number, it needs to be ‘despatched’ via the likes of Adstream or Dubsat to the TV station.



The number of TV stations broadcasting in HD is growing however many still broadcast in Standard Definition (SD) which is 1024 x 576 pixels. It is important to know which stations will be running your ad before you despatch, because if it’s one of their HD channels, then you should supply your ad in HD to those stations so it looks much better. The visual quality will be around 5 times that of Standard Definition. Even if your ad will be on a SD channel, some actually recommend despatching an HD file to Adstream, which after it’s reduced to SD, might actually come out a bit better compared to supplying a SD file in the first place.



There are many technical requirements for a TVC to meet broadcast requirements such as:

  • The TVC must have a Key Number which is maximum of 13 characters (this is the unique identifier for your ad and ensures the right ad goes on air)
  • This Key Number must be shown on the Clapper Board during pre roll
  • The file must be named as the Key Number only
  • There must be 8 seconds of clapper and countdown combined with 1 second and 24 frames of black
  • There must be a first frame indicator
  • Your commercial needs to be in and the duration must be exact (e.g. a 30 second ad must be 30 seconds)
  • There must be 3 seconds of black at the end
  • It must be rendered to either upper or lower field

There are strict requirements relating to the audio aspect of your TVC, which must be OP48 compliant. This needs to be stated on the clapper board. In addition, it must comply with FreeTV OP59 which is a loudness check.



This is a still image that plays on the video file before the commercial itself and is essentially information to identify and place the ad in the right spot. Clapper Boards typically include the Key Number, the client, production, duration, aspect ratio, date of production and indication of OP48 compliance.



While this might be self explanatory, it’s important to note that the ad must maintain the same aspect ratio throughout its duration, that means it must be either 16:9 or 4:3 aspect ratio.

The TV spectrum has a certain range of ‘legal’ colours and luminance. For example, if the whites in your TVC looks too ‘hot’, it’ll most likely exceed the legal spectrum and the ad will need to have this adjusted so it meets the requirements, before it can be aired.



After meeting the various technical and other requirements, your TVC has to be delivered as a video file. Acceptable video formats are:

QuickTime MOV (H.264)  |  QuickTime MOV (ProRes LT)  |  QuickTime MOV (ProRes 422)  |  Mpeg2

All the above need to supplied at 25 frames per second.

In terms of audio requirements, except for the Mpeg 2, the codec must be PCM (uncompressed), channels must be stereo, the bitrate must be 16 bit, little endian and the sample rate must be 48kHz.

After producing your TVC, it’s important that you’ve got the right professionals guiding you through the rigorous despatch process as briefly outlined above. Rocket Productions handles all despatch services for our TVC clients, so you rest assured that the ad will play as planned.

To find out how we can handle production and dispatch of your TV commercial, get in touch with us today.