Read the proportions as well as the dimensions
A media report can list width and height while also carrying sample or display aspect-ratio information. FFmpeg’s project documentation distinguishes these concepts and relates display aspect ratio to width, height and sample aspect ratio. The stored pixel grid alone is therefore not always the intended shape of the displayed picture. Keep all relevant geometry fields when inspecting a legitimate source file.
Use a simple worked relationship
With square samples, 1920 divided by 1080 gives a 16:9 display ratio. If samples are not square, their aspect ratio also enters the calculation. This is a geometric relationship, not a recommendation to rewrite every older programme as widescreen. A correct presentation can include side bars or letterboxing when the content and screen have different shapes. Filling every screen pixel may crop or distort the original composition.
Distinguish stretching from cropping
If faces look wider, investigate proportion handling. If proportions look normal but picture edges are missing, inspect zoom, cropping or overscan instead. These are different transformations and can require different controls. Compare the same scene and record whether subtitles or on-screen graphics are cut off. A screenshot can also be resized after capture, so keep the display observation separate from how an image appears in a support attachment.
Preserve source intent during a test
Start from an automatic or documented aspect setting and note the original value. Avoid applying a permanent stretch merely to remove bars. If only one item is wrong, retain its geometry report and player details for the publisher; if every input is affected, inspect the television’s settings. Editing aspect metadata in a personal file should be deliberate and reversible, with an untouched original retained for comparison.
Questions, answered
Are black bars always a playback fault?
No. They can preserve the intended proportions when content and display shapes differ. Investigate distortion or missing edges rather than assuming the screen must always be filled.