fix: Large Video Uploads Can Freeze or Crash Browser During Waveform Generation

[Krishnx21]

Description

This PR fixes a performance and stability issue where large uploaded videos were fully loaded into memory and decoded immediately for waveform generation.

Problem

Previously, waveform generation started automatically whenever TrimControl mounted. Large video files (400–500 MB) were read entirely into memory using file.arrayBuffer() and decoded via decodeAudioData(), even if the user never opened the trim feature.

This behavior could lead to:

• High memory consumption
• UI freezing and poor responsiveness
• Browser tab crashes on lower-memory devices
• Unnecessary processing for users who never use trimming

Changes Made

• Deferred waveform generation until it is actually needed.
• Prevented unnecessary audio decoding during initial editor load.
• Reduced memory usage by avoiding automatic processing of large uploaded files.
• Improved overall editor responsiveness when handling large videos.
• Preserved existing trimming functionality and waveform rendering behavior.

Testing

Verified the following scenarios:

• Small video uploads continue to generate waveforms correctly.
• Large video uploads no longer trigger immediate heavy processing on editor load.
• Editor remains responsive when opening large files.
• Trim functionality continues to work as expected when waveform generation is required.
• No regressions observed in normal editing workflows.

Impact

This fix significantly improves the user experience when working with large video files by reducing unnecessary memory allocation and preventing browser freezes or crashes during project initialization.

Closes #1450

[vercel]

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[github-actions]

✅ PR Format Check Passed — @Krishnx21

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This does not mean the PR is approved — it just means the format is correct.

[github-actions]

👋 Thanks for your PR, @Krishnx21!

Welcome to Reframe — a browser-based video editor built for everyone 🎬

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Quick checklist

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• Linked the issue this PR closes (e.g. Closes #123)
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Useful links

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Happy coding! 🎉

[Krishnx21]

@magic-peach can you please check this and let me know what i have to enhance ?