Export & Formats

How export works

Exporting in Vlexor happens in two different places. The web app has a dedicated export screen where you choose a target platform, a quality tier, and whether to burn captions into the picture — it's a fast way to plan and confirm settings for a project before you sit down to actually render it. The encoding itself, though, always happens in the Vlexor desktop app, driven by the same bundled FFmpeg engine that powers every other render in Vlexor.

That split exists because Vlexor renders locally: your raw footage is never uploaded anywhere to be processed, so whatever machine does the actual work has to be the one holding the files, and today that's the desktop app rather than a server. The web export screen doesn't push its settings to your project automatically — after confirming your choices there, you open the same project in the desktop app and set the Platform and Quality controls to match, then render from there. Treat the web screen as a planning step: it lets you preview exactly what a given combination of platform, quality, and captions will produce before you commit to a render.

• Platform — the target aspect ratio your footage is scaled and cropped to fit
• Quality — the output resolution and encoder settings
• Burn in captions — whether caption cues get baked permanently into the picture

Platform presets

Vlexor ships four platform presets, each tied to a target aspect ratio. YouTube targets the classic 16:9 widescreen frame. Shorts/Reels and TikTok both target the 9:16 vertical frame used across short-form video — Vlexor lists them as two separate options even though they produce the same aspect ratio, since they're different destinations. Custom doesn't force any particular frame at all; it keeps your source footage's own dimensions, rounded down to the nearest even pixel count FFmpeg requires for encoding, so you get back the same frame shape you shot in.

When a preset with a fixed aspect ratio is selected, Vlexor doesn't letterbox or pad your footage to fit the target frame — it scales the video up until it fully covers the frame, then crops the overflow from the center. In practice, exporting 16:9 footage to a 9:16 preset crops in from the sides, and exporting a taller clip to 16:9 crops the top and bottom. There's no manual reframing or repositioning control yet, so if your subject sits close to one edge of the frame, it's worth checking the crop before committing to a long render.

On the desktop app, where rendering actually happens, the Platform control lists YouTube, Shorts, and TikTok directly against your open project, each using the same scale-and-crop behavior described above. The Custom / Any-size option lives on the web configurator's four-way selector, for previewing an export that keeps your footage's native framing untouched.

• YouTube — 16:9 widescreen
• Shorts/Reels — 9:16 vertical
• TikTok — 9:16 vertical
• Custom — keeps your source footage's own frame dimensions

Quality tiers and resolutions

Vlexor offers three quality tiers, and each one maps to a specific, real target resolution rather than a vague high/medium/low label. 1080p renders to a 1920×1080 frame (1080×1920 on a vertical platform preset) and is labeled "Fast" in both the web configurator and the desktop app, since it uses the lightest encoder settings of the three. 4K renders to a 3840×2160 frame (2160×3840 vertical) and is labeled "Recommended" — the tier Vlexor steers most exports toward by default. 4K HDR renders at the same 3840×2160 (or 2160×3840) resolution as 4K, but adds real high-dynamic-range color and a heavier encoder, which is why it's labeled "Slowest."

Quality tier doesn't just change the target resolution — it changes the encoder and its settings too. 1080p and 4K both encode with H.264 (libx264) at CRF 21 and CRF 19 respectively, with 4K also stepping up from FFmpeg's "medium" encoding preset to "slow" for better compression efficiency at the larger frame size. 4K HDR switches encoders entirely, to H.265/HEVC (libx265) at CRF 20 with the "slow" preset, and encodes in 10-bit color (yuv420p10le) instead of the 8-bit color the other two tiers use — real precision headroom for a wider dynamic range, not an 8-bit source resampled upward.

• 1080p — 1920×1080, H.264 (libx264), CRF 21, "medium" preset — Fast
• 4K — 3840×2160, H.264 (libx264), CRF 19, "slow" preset — Recommended
• 4K HDR — 3840×2160, H.265/HEVC (libx265), CRF 20, "slow" preset, 10-bit color — Slowest

HDR metadata, audio, and the output file

The "HDR" in 4K HDR isn't just a label — Vlexor writes real HDR10 color metadata into the file when you choose it: BT.2020 color primaries, the SMPTE 2084 (PQ) transfer characteristic, and a BT.2020 non-constant-luminance colorspace tag. Those three flags are what tell a TV, phone, or platform player to decode and display the file's color as HDR, rather than treating it as ordinary SDR footage. Because that combination only makes sense on genuinely graded HDR material, this tier is meant for finishing a project you've actually color-graded for HDR — not as a default "highest quality" checkbox for ordinary footage, since it's also the slowest tier to encode by a wide margin.

Every quality tier, 4K HDR included, encodes audio identically: AAC at 192 kbps. All exports land in an MP4 container with the "faststart" flag set, which moves the file's index to the front so it starts playing immediately when uploaded to a platform or opened in a player, instead of needing the whole file downloaded first. The desktop app's save dialog defaults to a filename ending in .mp4 and only offers that extension — every Vlexor export, HEVC-encoded 4K HDR files included, comes out as a single .mp4 file.

Burning captions into the export

If your project has caption cues — whether you typed them yourself or they came from an AI-generated edit plan — the "Burn in captions" toggle on the export screen decides whether they end up in the final video at all. When it's on, Vlexor renders every caption cue as a real subtitle track and bakes it permanently into the picture at render time, using whatever caption style you set while editing. When it's off, captions are skipped entirely: there isn't currently a way to export captions as a separate file alongside the video, so turning burn-in off means an export with no visible captions, not an export with a sidecar subtitle file.

Captions are rendered through libass, the same subtitle engine used across the video industry, which handles Arabic (and other right-to-left scripts) shaping and text direction automatically. That means Arabic captions burn in correctly by default — there's no separate RTL mode to enable or extra configuration needed to get the text direction right.

Real render progress, not a stuck bar

When a render is running in the desktop app, the progress bar you see is tracking the actual encoder, not a fake animation timed to guess how long things usually take. Vlexor launches FFmpeg with `-progress pipe:1`, which makes it stream a continuous, machine-readable log of exactly how far into the output it currently is. The desktop app reads that stream line by line, pulls the `out_time_ms` value from each update, and divides it by the total duration of the clip being exported to compute a real percentage — so a 30-second export and a 3-minute export both report accurate, proportional progress rather than an arbitrary curve.

That percentage only ever moves forward: Vlexor discards any reported value that isn't strictly higher than the last one it showed, so the bar can't flicker backwards even if FFmpeg's own reporting jitters slightly. If you cancel a render partway through, Vlexor sends a real stop signal to the exact FFmpeg process that's running, not just to the UI — so the encode actually stops immediately rather than continuing in the background after the progress bar disappears.

Rendering from the desktop app

Rendering starts with a native Save dialog — you pick a destination and filename (Vlexor suggests velxor-export.mp4), with .mp4 as the only offered extension. Before you click "Render & export," you set the same Platform and Quality controls described above directly against the project open in the desktop app, along with the trim range for the portion of your source clip you actually want exported. That trimmed range is also what Vlexor uses as the total-duration denominator for the progress percentage described above, so the bar reflects the export you actually asked for rather than the length of your original footage.

Once you click "Render & export," the progress card takes over: a live percentage, a filled progress bar, and a "Cancel" button for as long as the render is running. When it finishes, that's replaced with an "Exported →" confirmation showing the filename you saved to. If FFmpeg exits with an error partway through, Vlexor surfaces the raw error message instead of a generic failure, so you can see exactly what went wrong — a codec issue, a full disk, and so on.

Choosing the right settings

For a quick check of how an edit plays before committing to a longer render, 1080p is the fastest tier and a reasonable default while you're still iterating on cuts, captions, or color. For nearly everything you intend to publish — YouTube, Shorts, Reels, TikTok — 4K is the tier Vlexor recommends by default: platforms re-compress whatever you upload anyway, and starting from a sharper 4K master gives that re-compression more to work with than a 1080p source would. Reach for 4K HDR only when your footage and grade were actually done with HDR in mind; since it's real 10-bit HEVC with HDR10 metadata rather than an upsampled version of the same footage, exporting ordinary SDR footage through it won't make the video look any better, and it's measurably the slowest of the three tiers to encode.

• 1080p — quick iteration and previews while you're still editing
• 4K — the recommended default for most published exports
• 4K HDR — only for footage that was actually shot and graded for HDR