# Low-CPU Video Preview Generator

Create a preview montage from 5-10 evenly spaced video clips without re-encoding.

> Canonical page: https://elysiatools.com/en/tools/video-preview-generator

- **Category:** Video Processing

- **Keywords:** video, preview, montage, clips, stream copy, low cpu, ffmpeg

## Overview

Choose 5-10 clips and 2-5 seconds per clip. The tool checks that non-overlapping boundaries fit the source, then uses FFmpeg input seeking with -ss and -t before -i and -c copy. Clips are concatenated with the concat demuxer, so this is a low-CPU stream-copy operation rather than a precision timeline edit. The output is MP4 and keeps audio only when requested.

## Inputs

- **Video File** (file)
- **Number of Segments (5-10)** (number)
- **Duration per Segment (2-5 seconds)** (number)
- **Preserve Audio** (checkbox)

## When to use

- Create a quick preview of a long video using evenly spaced clips.
- Review or share a lightweight video montage without a high-CPU re-encoding step.
- Show a short sample of recorded footage while keeping the source audio when needed.

## How it works

- Upload one video file.
- Choose 5 to 10 segments and set the duration of each segment from 2 to 5 seconds.
- The tool checks that the selected, non-overlapping clip boundaries fit within the source video.
- The clips are trimmed with stream copy, concatenated, and returned as an MP4 file with optional audio.

## Use cases

- Generate a quick overview of a long recording for review.
- Create a short montage for sharing or internal video selection.
- Sample evenly spaced footage from source videos with low CPU usage.

## Frequently asked questions

### What video files can I upload?

Upload one file accepted by the video input, which supports video/* files.

### How many clips can the preview contain?

You can select between 5 and 10 segments.

### How long is each segment?

Each segment can be 2 to 5 seconds long, using 0.5-second increments.

### Does the tool re-encode the video?

No. It uses stream copy, making the operation lower in CPU usage than re-encoding.

### Can I keep the video's audio?

Yes. Audio is preserved by default and can be disabled with the Preserve Audio option.

## Related tools

- [Audio Spectrogram Generator](https://elysiatools.com/en/tools/audio-spectrogram-generator): Generate a spectrogram image from an audio file or a video audio track
- [Audio to Spectrogram Video](https://elysiatools.com/en/tools/audio-to-spectrogram-video): Create a video from audio with a spectrogram visualization
- [Audio to Waveform Video](https://elysiatools.com/en/tools/audio-to-waveform-video): Create a video from audio with a waveform visualization
- [Image Sequence to Video](https://elysiatools.com/en/tools/image-sequence-to-video): Convert uploaded image files or a ZIP archive of frames into a video, sorted naturally by filename
- [Batch Rewrap](https://elysiatools.com/en/tools/batch-rewrap): Batch remux media files with stream copy.
- [Stream Smart Remux](https://elysiatools.com/en/tools/stream-smart-remux): Rewrap media containers with stream copy.
- [Video Audio Remove](https://elysiatools.com/en/tools/video-audio-remove): Remove the audio track from a video file, keeping only the video stream
- [Video Dual Audio Merger](https://elysiatools.com/en/tools/video-dual-audio-merger): Mux two audio tracks into one video in copy mode.

## Samples

- [Video Samples](https://elysiatools.com/en/samples/video-samples): Sample video files in different formats and orientations
- [Video AV1 Samples](https://elysiatools.com/en/samples/video-av1-samples): Sample video files encoded in AV1 format
- [Video H.264 Samples](https://elysiatools.com/en/samples/video-h264-samples): Sample video files encoded in H.264 (AVC) format
- [Video H.265 Samples](https://elysiatools.com/en/samples/video-h265-samples): Sample video files encoded in H.265 (HEVC) format