====== ffmpeg - Video - Resize - Convert to 4K (3840x2160) ======

<code bash>
ffmpeg -i input.mp4 -vf "scale=3840:2160" -c:v libx264 -crf 23 -c:a copy output.mp4
</code>

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===== For enhanced quality =====

<code bash>
ffmpeg -i input.mp4 -vf "scale=3840:2160:flags=lanczos" -c:v libx264 -crf 23 -c:a copy output.mp4
</code>

<WRAP info>
**NOTE:**  This uses the **Lanczos** scaling algorithm, which can provide better results for upscaling.
</WRAP>

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