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Delivering broadcast compliant commercials for UK TV.  



UK broadcasters aren’t allowed to show ads that are misleading, harmful or offensive and so must comply with either the BCAP or CAP codes. Ads seen in normal airtime (‘Linear’ ads) must comply with the BCAP code and ads shown on the ‘On Demand’ platforms (‘VOD’ ads) must comply with the CAP code. To this end, Clearcast is in place to check and clear UK ads prior to broadcast.



Clearcast is a non-governmental organization owned by six UK commercial broadcasters: ITV, ITV Breakfast Ltd, Channel 4, Channel Five (UK), British Sky Broadcasting and Turner. They clear TV ads for broadcast on more than 250 UK commercial channels and services.

Although it is mostly advertising agencies that deal with Clearcast in fact, anyone can register with them, whether ad agency, client, post production house, freelancer or PR company. All clearances are free if the ad is being transmitted on a channel that they clear for. The only time a cost is incurred is if you supply a late submission that requires fast tracking. To avoid this you should allow up to three weeks for the entire process.

If all goes well, clearance is usually a three stage process which all happens via 'CopyCentral', Clearcasts new online submissions portal which has replaced their previous system, 'Adway".


Stage 1. Submit the script.

You firstly need to submit a script ( even if the ad has already been made ) via CopyCentral using a template downloadable from the website. This is a written breakdown of your ad that if supplied during pre-production, allows any initial issues and concerns to be addressed before any significant costs have been incurred. This stage is the longest as it requires a good deal of due diligence. Here any claims you make during the ad such as "Our company is the best in the world' or 'Our product will make you more attractive to the opposite sex" will need to be checked and substantiated. So beware of wild claims and false promises!

There are a number of key areas that always require substantiation including but not limited to: Testimonials and endorsements, claims, price reductions and special offers, credit offers, food products and gambling/gaming services.


After the script has been approved you can go away and produce your ad with a reasonable degree of confidence so long as you stick to script, 


Stage 2. Submit a rough cut. 

It is a good idea to submit a rough cut so Clearcast can check you’re in line with the approved script. This stage is voluntary but highly recommended. Typically you might want to do this after the edit but before colour grading and sound mixing to save on the cost of possibly having to do this twice. During this process the ad will be checked for flashing images and regular patterns using HFPA-X, the HardingFPA analysis software. This is to protect members of the viewing public who suffer from photosensitive epilepsy. On completion, you will receive via email a certificate which states 'passed’, ‘passed with caution’ or ‘failed’. The certificate includes frame by frame analysis of failed submissions together with an indication of what caused it to fail.


Stage 3. Submit the finished ad.

When you submit the finished ad, it will again be checked for flashing images and regular patterns as a matter of course. "Supers" the legal or     regulatory 'small print' superimposed onto ads to provide additional information must adhere to rules regarding the minimum height of the text                                                                                                    onscreen. Text size is the vertical height of the text measured in terms of the                                                                                                          number of television lines it occupies. Clearcast have made a special minimum text                                                                                                height test card to check this. The minimum height of text required is dependant on                                                                                                the resolution of the file.




Resolution                    Lines w Solid Background                    Lines w non-solid background


720X576                        14                                                                  16

1024X576                      14                                                                  16

1280X720                      Unsupported                                                ---- 

1920X1080                    26                                                                  30

It is a requirement that "Supers" are on screen long enough for them to actually be read which can be a massive pain if there is a lot of text and there usually is. For this reason, Clearcast provide a duration of hold calculator to enable you to work out how long each word and caption need to be held on screen for but you can roughly work it out using the following formula: ‘ Short’ (9 words or less) captions: 0.2 seconds per word +2 seconds recognition time. ‘Long’ (10 words or more) captions: 0.2 seconds per word plus 3 seconds recognition time.


Clock Number/Material I.D

Every ad is required to have a unique clock number. The final version of each commercial must begin with a full countdown clock, the name of the product, the commercial unique identification number and the commercial length. This unique identification number will be used to identify your ad by ourselves and the broadcasters airing it throughout the compliance process, through to transmission and post- transmission reporting. The clock number should be 15 characters long and follows the following formats: Product name Identifier, ( 3 letters ) agency copy number, ( 4 letters plus 3 numbers ) and the commercial item duration ( 3 numbers ). For example, CTS/HXFA321/030

Filenames should follow the unique Clock Number assigned to it, in UPPERCASE, with the extension “.mxf” in lowercase. Allowable characters are ‘A-Z’, ‘0-9’, & ‘_’ The underscore is used in place of a forward slash. Forward slashes are not acceptable. Here is an example: • CTS/HXFA321/030 Becomes: CTS_HXFA321_030.mxf (Please note the use of underscores, not hyphens). The filename of the associated metadata xml shall have the same naming convention e.g. CTS_HXFA321_030.xml

Timeline Layout.

Annoyingly there seems to be some differences in the timeline specifications between Clearcast and the Digital Production Partnership.

Although minor it would mean having to generate a completely different version of the file. How did this happen? The whole idea of the DPP was to standardise and simplify the process. The DPP spec lists a 7 sec clock or ident. The Clearcast spec lists a full 30 sec clock.

The DPP requires 3 secs of black starting at 09:59:57:00 while the Clearcast spec requires black to start at 09:59:57:06, 6 frames later.       There are an optional 2 frames peak white and 1 frame of tone that can be added at the 09:59:57:06. 


The DPP documentation is below... 

"All Commercial or Sponsorship material delivered on file must be laid out so that the start of message (SOM) is at timecode 10:00:00:00 as specified in the MXF Material Package timecode track. The SOM at 10:00:00:00 is defined as the first frame of vision that will go to air. Please note that it is usual for sound and vision to be automatically cut to air on transmission, so early vision or sound is not normally required. Vision may fade up from black starting at 10:00:00:00 if desired. There should be 6 frames of audio silence at the start and end of the item and the duration should not exceed the stated length. At the end of the item there should be a 5-second hold on vision, completely still (No ‘Living Freezes’ or animations). A single commercial or Sponsorship asset will always be played out from the start of message (SOM) to the end point without interruption. The IN-point (SOM) and DURATION for the continuous playback section must be included with the delivery metadata. As per the diagram “Duration of Essence” does not include the clock or black prior to the essence or the five-second vision hold after the essence."



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