<p>The reason your exported file is huge is likely to be due to the Export settings chosen when you exported. The resolution you're planning to export at (3840 x 4320) is larger than 4K which is realistically the largest format most people use for viewing videos.</p>
<p>I would try re-exporting your final video as an mp4 video with an h264 codec at 3840x2160 resolution with a bitrate of 12Mb/s, and see how the exported video looks in terms of quality and file size.</p>
<p>Quality and file size are a trade-off. For a given codec and resolution &amp; frame rate, larger files (higher bit rate) will result in higher quality files.</p>
<p>I don't know the OpenShot software, but from the look of the <a href="https://www.openshot.org/user-guide/" rel="nofollow noreferrer">manual</a>, you can manually adjust the export settings in this window:</p>
<p><a href="https://i.sstatic.net/I1ftdJWk.png" rel="nofollow noreferrer"><img src="https://i.sstatic.net/I1ftdJWk.png" alt="enter image description here" /></a></p>
<p>YouTube has a guide to bitrates etc here which is useful for working out export formats even if you don't want to publish to youtube:</p>
<p><a href="https://support.google.com/youtube/answer/1722171?hl=en#zippy=%2Cbitrate" rel="nofollow noreferrer">https://support.google.com/youtube/answer/1722171?hl=en#zippy=%2Cbitrate</a></p>

CC BY-SA 4.0
2024-07-11T18:15:45.450Z
So there's no easy way to just use their existing bitrates and file sizes to infer a reasonable bitrate for the combined video? That's the frustrating part for me. I don't understand why the file sizes aren't marginally additive (obviously somewhat bigger for the upscaling of the 1080p video)
cma0014
CC BY-SA 4.0
2024-05-21T08:22:42.163Z
2024-05-21T08:22:42.163Z
tomh
<p>I have a three camera dash cam (front, rear, cabin). The front is 2160p and the rear is 1080p. I would like to combine two simultaneous videos (front and rear) into one 3840 x 4320 video (stacked vertically, 1080p  upscaled) without producing a gigantic file.</p>
<p>I tried to do this in OpenShot with a custom profile, and it was &quot;successful&quot; in that the video was formatted correctly... but it was 17GB and took 5 hours to render on my 5950x. The source files are 2:00 long and 240MB and 80MB respectively. I would like a video similar in size to the combined size of the source videos.</p>
<p>Any tips on how to combine them without a bloated, rendered vid?</p>

<video-editor>
How to combine front and rear dash cam video in split screen without gigantic file size?
cma0014
# How to combine front and rear dash cam video in split screen without gigantic file size?

(Asked by: username_0 on 2024-05-16)

I have a three camera dash cam (front, rear, cabin). The front is 2160p and the rear is 1080p. I would like to combine two simultaneous videos (front and rear) into one 3840 x 4320 video (stacked vertically, 1080p upscaled) without producing a gigantic file.

I tried to do this in OpenShot with a custom profile, and it was "successful" in that the video was formatted correctly... but it was 17GB and took 5 hours to render on my 5950x. The source files are 2:00 long and 240MB and 80MB respectively. I would like a video similar in size to the combined size of the source videos.

Any tips on how to combine them without a bloated, rendered vid?

**Tags:** video-editor


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## 1 answers

### Answer by username_1 on 2024-05-21. Score: 1

The reason your exported file is huge is likely to be due to the Export settings chosen when you exported. The resolution you're planning to export at (3840 x 4320) is larger than 4K which is realistically the largest format most people use for viewing videos.

I would try re-exporting your final video as an mp4 video with an h264 codec at 3840x2160 resolution with a bitrate of 12Mb/s, and see how the exported video looks in terms of quality and file size.

Quality and file size are a trade-off. For a given codec and resolution & frame rate, larger files (higher bit rate) will result in higher quality files.

I don't know the OpenShot software, but from the look of the [manual](https://www.openshot.org/user-guide/), you can manually adjust the export settings in this window:

[![enter image description here](https://i.sstatic.net/I1ftdJWk.png)](https://i.sstatic.net/I1ftdJWk.png)

YouTube has a guide to bitrates etc here which is useful for working out export formats even if you don't want to publish to youtube:

<https://support.google.com/youtube/answer/1722171?hl=en#zippy=%2Cbitrate>

> **Comments:**
> **username_0**: So there's no easy way to just use their existing bitrates and file sizes to infer a reasonable bitrate for the combined video? That's the frustrating part for me. I don't understand why the file sizes aren't marginally additive (obviously somewhat bigger for the upscaling of the 1080p video)  

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