An attached cover can fool your video-dimension check

https://seedancecheap.com

A video-delivery check can report the dimensions of cover art instead of the moving picture. Reading the first stream is the mistake: a stream marked as video can be an attached image.

Here is a small, reproducible developer note using an invented metadata report. It contains no customer footage or records, makes no generation request, and uploads nothing.

A quick local check

With an existing ffprobe installation, run this against your downloaded file:

ffprobe -v error -select_streams V:0 -show_entries stream=index,width,height -of json "delivered.mp4"

The uppercase V is deliberate. The official ffprobe stream-specifier documentation distinguishes all video streams (v) from video streams excluding attached pictures, thumbnails and cover art (V). The :0 selects the first matching stream; it does not prove that this is the intended main picture in a multi-angle file. Use V without :0 to list the matching picture streams and choose the right one.

This command reads metadata and prints selected fields. It does not edit or decode-review the complete video. An empty stream list should not be treated as a passing picture check.

Reproduce the first-stream mistake

Get our frozen Python inspection example. Save the code below as cover_case.py next to inspect_video.py, then run python cover_case.py (or python3 on your system). Only Python's standard library is needed for this synthetic case.

from inspect_video import summarize

report = {
    "streams": [
        {"index": 0, "codec_type": "video", "width": 300, "height": 300,
         "disposition": {"attached_pic": 1}},
        {"index": 1, "codec_type": "video", "width": 1280, "height": 720},
        {"index": 2, "codec_type": "audio"}
    ],
    "format": {"duration": "30.08"}
}
first = report["streams"][0]
print("Naive:", first["width"], first["height"])
result = summarize(report)
print("Selected stream:", result["selected_video_stream"])
print("Moving video streams:", result["moving_video_streams"])
print("Encoded pixels:", result["encoded_pixels"])

The exact local run printed:

Naive: 300 300
Selected stream: 1
Moving video streams: 1
Encoded pixels: [1280, 720]

The naive lookup reports the invented 300 × 300 cover. The inspected report selects stream 1 and reports the 1280 × 720 moving picture. This specifically exercises the Python example's attached_pic exclusion. It is not a claim that this fixture covers every thumbnail disposition or every multimedia container.

Keep the units and limits clear

We also ran the ffprobe command on our existing public portrait sample; it reported a 720 × 1280 stream. That was a separate command smoke check, not a real-file reproduction of the invented attached-cover case.

Encoded dimensions describe an export. Rotation metadata and non-square pixels can affect display. A large export may have been upscaled. An audio stream does not establish usable or synchronized sound. Watch and listen to the whole delivered clip before accepting it; this note makes no creative-quality, native-generation-resolution or delivery-success-rate claim.

For the broader workflow, our complete delivered-video inspection guide covers duration, audio presence and the limits of metadata checks.

From the SeedanceCheap team, with Codex. We are an independent studio. The synthetic example above was run locally with the linked script. Prompt planning is free; video generation is separate. Check live Studio availability and funding terms before submitting or buying.

 

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