If you ever find yourself in a situation where you have accidentally shot larger than 1920x1080 and want need to transcode it, Adobe Media Encoder provides users with the ability to transcode single clips or a bunch of clips all together.
Locate Adobe Media Encoder in the Applications the “Applications” folder.
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You will notice the panel layout as such:
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The easiest way to begin transcoding your incorrectly shot footage is to drag it from Finder into the Queue panel.
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Click Click on the underlined codec.
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You will then be taken to the Export Settings window where you will then go ahead and change
The Format to QuickTime
Video Codec to Apple ProRes 422
Resolution to 1920 x 1080
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Once you are happy click on Then change Output Name and save to desired location.
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Then click Then hit OK
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You’ll then be directed back to the Encoder where you will see the file now loaded up with the correct settings.
Go ahead and hit the green triangle at the top right hand corner to being processing.
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Wait for your footage to transcode and you're done.
If you need to add more footage to the queue, you can just do the same by dragging them all into the queue panel and repeating the process.