Video thumbnails - suggest taking a capture at 1s rather than 0s

[rayearth2162-ship-it]

Enhancement

Sometimes the 0s thumbnail produces a blank / black thumbnail - If the video starts with a black frame, a fade-in, or container delays, the thumbnail will end up entirely black.

adding the below in app/Image/Handlers/VideoHandler.php seems to have solved the issue:

    public function extractFrame(float $frame_position = 0.0): ImageHandlerInterface
    {
            // Force a 1-second delay if the position defaults to 0.0
            if ($frame_position === 0.0) {
                    $frame_position = 1.0;
            }
            try {

[MLuc24]

Worth knowing before this gets patched: Lychee isn't actually aiming at 0s. Both callers of extractFrame compute a position first, and they target the middle of the video:

$position = is_numeric($state->photo->aperture) ? floatval($state->photo->aperture) / 2 : 0.0;
$state->source_image = $video_handler->extractFrame($position);

Same line in SizeVariantDefaultFactory.php. The /2 only makes sense because that field holds the video's duration rather than a camera aperture — a leftover of the old schema, which a migration describes as "updating structure of photo table from focal/aperture to fps/duration".

So 0.0 isn't the intended behaviour, it's the fallback when that value isn't numeric. Which means the black thumbnails you're seeing are telling you something more specific than "0s is a bad default" — for those particular videos the duration wasn't available, so the midpoint couldn't be computed and it fell back to the first frame.

That makes your fix work, but it sits a layer below where the decision is made. Forcing 1.0 inside extractFrame also overrides any caller that deliberately asks for frame 0, and it hides which path was taken. Changing the fallback instead targets exactly the failing case and states the intent:

$position = is_numeric($state->photo->aperture) ? floatval($state->photo->aperture) / 2 : 1.0;

One caveat either way — 1s is still a guess against a container that might have a longer fade. If the duration is known the midpoint is strictly better, so it may be worth checking whether duration is being populated for the videos that misbehave. If it isn't, that's the more useful bug, and the thumbnail is just the visible symptom of it.

(Minor thing on the patch as written: $frame_position === 0.0 is a strict float comparison. It happens to work for the literal default, but it's the kind of check that silently stops matching if the value ever arrives via a computation.)

[ildyria]

I think having this value configurable would be a better approach: user can chose to have either the first frame (or 1s frame) or the middle frame.

[ildyria]

Here we go: #4624