Variable frame rate clips and Premiere Pro proxies

Variable Frame Rate video clips may import ok into modern video editors, but they often cause issues when you try to perform tasks like creating proxies and sync with out clips. To ensure these clips give you the most flexibility in your editing, it’s best to convert them to constant frame rate clips. This is very easy as you can see in this video. Handbrake can be downloaded from –

Video Transcript

Hi guys Simon here. In this video we’re going to look at converting variable frame rate clips into constant frame rate. While most editors like Davinci resolve or premiere pro handle variable frame rate files without an issue, there are some features like creating proxy files in premiere pro that just don’t work very nicely when using variable frame rate files.

I’ve got a 4K screen recording clip that I recorded a little while ago using Camtasia. Now it was set to 30 frames per second, but I was doing some fairly CPU intensive tasks and it looks like my PC couldn’t keep up with what I was trying to record, so it started dropping some frames which I didn’t realize until I went to bring the clip into premiere pro and it showed that rather than 30 frames per second it was a 26. 47 frames per second clip.

If I try to create a proxy file from this variable frame rate file, Media encoder just sits there chewing through all my free ram and then starts paging all my free hard disk space into its page file. So eventually just crashes and doesn’t create the proxy file. So in order to use the variable frame rate file in premiere for creating proxies, the solution is to transcode that variable framerate file into a constant frame rate file using a tool called Handbreak. Then we can re import it back into premiere pro and create our proxies without any problem.

Let’s jump over to the PC and have a look OK. So to show you what I was talking about with the media encoder were in premiere pro and if we look down of imported in my MP4 clip and we can see that the frame rate is 26. 47 frames per second. If we right click and click proxy and create proxies. Will select just one of the standard built-in proxy presets for media encoder and then click on OK. That will start up media encoder and start trying to create the proxy file.

Now if we switch over to my task manager on my PC, you can see here that I’ve currently got 18. 5 gig of free ram and you can see immediately that the ram starts to be used up. So if we go back to media encoder. We can see that it has started to encode the file. Now if we keep an eye on the task manager. And look at the memory, we can see that it immediately starts just chewing up any available memory. Now on a standard constant frame rate file, while media encoder will use up some ram, it won’t just completely chew up any available round that’s leftover.

So if we keep monitoring this for a little while and I’ll let it run for a few minutes, we can come back and have a quick look and see what it’s done. OK, so we’re now about 5 minutes into media encoder trying to create the proxy and you can see that the memories now down to about 3 gig free sites at about running about 90% ram usage. So once it swallows up the rest of that ram, it’ll start creating a page file. You can see it started to already chew up free disk space if we keep refreshing on the C Drive. It’s just paging more and more data to disk.

So what will happen is in about four or five minutes. This will completely fail. And come up with an error, so will shut this off for now. And no, we don’t want to finish the current file, we just want it to stop. So we close this back down. And refresh we can see we’re getting all our free disk space back. That was pay that went to the paging file and our Rams drop drop right back down to 26 gig free.

So now in order to do this another way we use a tool called handbrake which is a free tool and I’ll put a link to in the description to the to the website to download handbrake. OK so to transcode a file using handbrake we just click on the left menu to open a file. Select our file path, select the file that we want to transcode. It’ll then scan the file and show a preview.

Now there are a number of presets that we can follow so we can go in and select the closest one to what you want to do I have a couple of custom presets, so if we went in and said, well, let’s go very fast 1080. And we can see we want to keep it as MP4 format. We want to align the audio and video. We don’t necessarily need to make it web optimized at this point. It’s currently a 4K file, so you can either leave it at 4K or drop it down to 1080, which will do because we only need a 1080 file. Filters I don’t typically change video. We want to leave as H264.

Now this is where we want to set our frame rate to our desired frame rate. Now I’m in Australia, so we want we want to set this to 25 frames per second and set constant frame rate now under our encoder profile we want to set that to high and for a 1080 file we can set this to 4. 2 for encoder level. That will give us the best quality file that we can get. I don’t typically change anything in the audio because it’s picked up the correct codec and everything.

Now we can save this preset if we like. I don’t want to say that at this point, because I’ve already got some presets. So now we just click on start in code and the video will start encoding. It shows us down the bottom here where it’s being saved. We could have changed that if we wanted to, but that’s perfectly fine folder for it to saving too. And you can see down the bottom where what it’s actually doing with its encoding.

It’s now 1% of the way through, and it tells you the frames per second that it’s that it’s transcoding at, and gives you an estimate of the time remaining, so will pause the video here and come back when the transcoding is complete. OK, so now our transcoding has completed.

We can seek you finished, and if we switch back to the output folder, we can see we’ve got our MP4 file. It’s considerably smaller because we’ve changed it from a 4K file to a 1080P. And if we look at the details, we can see it is in 25 frames per second. So if we copy this into the folder for our project. And then drag it into premieres project folder.

We can now see it reports as 25 frames per second. So now if we right click go to proxy an create proxies, select their same preset as last time click on OK. And running a meteor encoder. This will go through and quite easily in quite happily create the proxy file for this file. So once the transcoding of the proxy starts on the constant frame rate file, you can see that the memory stays level and it’s happily and quite quickly creating the proxy file.

Thanks for watching if you enjoy this clip, Please remember to like the video and subscribe to the channel for more videos. Just like this one. Thank you.

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I’m the Technical Director at Expeed Technology in Adelaide, South Australia. In my day job I work on both Windows and Linux web hosting technologies and Windows and Web .NET development. In my spare time I tinker with video production, photograpy, and all things Azure, including IAAS, PAAS and Serverless. You can find me on Twitter over at @simonholman 





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