Container and codec: the wrapper and the compression
A container is the wrapper, named by the file extension. A codec is the method used to compress the picture inside it. Ad specification pages usually publish a list of acceptable containers and say nothing about codecs at all. As of 2026-09-12.
| Layer | What it is | Usually published |
|---|---|---|
| Container | The file format and its extension | Yes, as a short list |
| Video codec | How the picture is compressed | Rarely |
| Audio codec | How the sound is compressed | Almost never |
| Colour handling | How values are tagged and interpreted | No |
Inclusion rule. Layers of a delivered video file, ranked by how often an ad specification page mentions them. A requirement enforced by an upload tool but absent from the page is not listed. Order. Outermost layer first.
1A container list is easy to satisfy and easy to get wrong
The lists are usually broad enough to include formats no current renderer produces, so clearing them is trivial. What catches people is that different routes into the same surface sometimes accept different lists.
So a checklist has to know which route an ad is going down before it can check the container. That is a workflow fact rather than a technical one, and a cheat sheet that merges the routes hides it.
2Codecs are where the silent failures live
Because specifications rarely name a codec, an unusual one can pass a written check and then be re-encoded badly, or refused by a tool further down the line. Nothing in the published rules warns about it.
The practical defence is to deliver in the ordinary combination for the surface rather than the ordinary combination for the renderer. Those are not always the same, and only one of them is being checked.
3Colour tagging is the quietest of the four
A file encoded one way and tagged another looks correct in one player and wrong in another, and no ad specification these sheets read mentions it. It is a common cause of a piece that looks washed out only after upload.
Like bitrate, it can only be found by inspecting the delivered file. It belongs on a checklist rather than in a register, because there is no published figure to record.
A vocabulary entry: the definition, plus how the specification pages on these sheets usually publish it. Table checked 2026-09-12. Nearby entries: Text and image paths, Reference image.
4Making the ad itself
For ad work around “Container and codec”, SceneMixer's pages explain how its ad projects are produced:
On the end card, yes, along with the product name, the tagline and the call to action, in the language of the ad.
SceneMixer, AI Ad Video Generator — “Will my brand name appear in the video?” (read 2026-10-13)
Character sheets are always portrait and scene images always widescreen, whatever ratio the videos use.
SceneMixer, Vertical 9:16 or Landscape 16:9 — “Will choosing 9:16 make my character images vertical?” (read 2026-10-13)