Check an HLS compatibility version against used features

The useful distinctions

• EXT-X-VERSION declares a protocol compatibility version.
• Floating-point EXTINF durations require version 3 or later.
• The version declaration must agree with the features used.

Inventory features before choosing the number

The invented playlist uses decimal segment durations and ordinary media references. Start its review by listing those features, then compare that list with the documented minimum compatibility requirements. This is easier to audit than selecting a large version number and assuming it makes every possible feature valid. A declaration describes a contract that the playlist, associated media, and delivery behavior must satisfy.

Do not equate version with picture quality

Version three does not mean three quality levels, a resolution, or a bitrate. Increasing the number would not change the encoded samples in the two referenced files. Conversely, adding a feature can require a changed declaration even when the picture remains identical. For a more complex publication, preserve a small feature-to-requirement table alongside its authoring configuration. That table should identify which requirement caused a minimum, rather than merely recording the final number. The sample intentionally avoids newer features so the review can be followed from the visible text. It has not been checked with a platform player and makes no statement about any particular device's support. The feature inventory is the useful review artifact: list each used construct and its required compatibility floor, then compare the declared number. Do not raise the declaration merely to make an old playlist look current.

Worked example · synthetic

The decimal EXTINF values are the visible feature motivating version 3 here. The example declares 5.5 seconds in total, independently of the compatibility number.

Synthetic text example; no network operation has been performed.

#EXTM3U
#EXT-X-VERSION:3
#EXT-X-TARGETDURATION:3
#EXTINF:2.75,
one.ts
#EXTINF:2.75,
two.ts
#EXT-X-ENDLIST

Check the interpretation

• Inventory every used feature.
• Compare with the feature's minimum compatibility requirements.
• Do not report a version change as a media-quality upgrade.