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Video comes in two shapes, and AdCP models them as two asset types with opposite rules.
  • A hosted video file is a concrete file (an MP4) that gets served as is. Its resolution, duration and codec are baked in. Format kind video_hosted, asset type video.
  • A VAST tag isn’t a file. It’s a URL pointing at a video ad server’s decision at play time. The ad server can return several renditions at different sizes and bitrates, and the player picks one. Format kind video_vast, asset type vast.
The asset must match the format. An MP4 is a hosted video, not a VAST tag, and labeling it VAST doesn’t make it one. Use a VAST tag only when you have a real VAST URL.

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Dimensions belong to a file, not a tag

A hosted file has one native resolution, so Semicola sends its width, height and duration_ms with the asset when it syncs the creative to a seller. A VAST tag has no single size: each rendition inside the VAST response carries its own. So a vast asset carries only its url and, if you give one, its vast_version.

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Where size and duration rules live

Rules like “16:9, up to 30 seconds, MP4” are constraints on the format, not properties of the asset. An asset describes what you’re sending; a format describes what a placement accepts:
  • size (exact width and height, or an aspect ratio);
  • duration (a maximum, or an exact length);
  • containers the format accepts.
When Semicola matches a creative to a seller’s formats, a hosted file is checked against those constraints up front: A VAST tag is checked at serve time, when the player picks a rendition. For delivery, a hosted video should be MP4 (H.264 video, AAC audio). Editing formats like MOV are sources, not delivery files: convert them first.

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Add a VAST tag

Create a creative whose primary asset is a URL (urlAsset) with urlType: "vast", the tag url, and optionally vastVersion: 2.0, 3.0, 4.0, 4.1, 4.2 or 4.3. Pass it to save_creative, or POST /api/v2/buyer/advertisers/{id}/creatives/create. A tag sheet can also bring VAST URLs in; see Inspect a tag sheet. Upload a hosted video from the creative library (up to 2 GB); see Creatives.

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Not available yet

  • Inline VAST XML: a VAST creative is always a tag URL.
  • Automatic transcoding, trimming or letterboxing. The fit result names the adaptation; nothing converts the file for you.