Adobe Premiere Pro Forum
Premiere Pro lagging with H.264
Premiere Pro lagging with H.264
by James Agro on Mar 24, 2017 at 10:50:54 am

Hello everyone, I've found a problem, in which Premiere Pro (preview) lags and skips around when attempting to edit H.264 directly, and I was told to just re-encode to something like utvideo, which works, but I'm working with around 100GB of H.264, and re-encoding this is going to take many times as much space and time. So, something that I've noticed is that Aftereffects seems to preview the video fine, however, Premiere Pro seems to lag, and not like the files at all, unless they are re-encoded, then they work flawlessly.
My system specs are:
AMD Ryzen 7 1800x @ 3.8GHz,
32GB DDR4 @ 2113MHz
GTX 1080 GPU

Which should be fine for editing, correct? So, I'm not quite sure if this can be solved, as i previously edited H.264 directly with my i7 system, which I no-longer have.
Any ideas or suggestions would be greatly appreciated.

Edit: I have tried enabling/disabling CUDA and yes, PP and AE both have access to 28GB's of system memory. Also, CPU utilization is extremely low >2%. I'm working with 20Mbps H.264 in 1080P.

Re: Premiere Pro lagging with H.264
by Jud Archer on Mar 24, 2017 at 11:53:27 am


The advice you were given is the correct answer. H.264 is an extremely processor intensive codec and is not generally considered good for editing. Basically it is so compressed that your computer's cpu is having to decode it on the fly, which is a big burden. Choose a DNX or ProRes variety proxy file.

The latest version of Premier will automatically convert to a proxy on import if you set it up that way. Have you experimented with this? If your computer has trouble playing the DNX or ProRes then there are bigger problems going on. Perhaps drive speed?

Good luck.

Jud Archer
Apple / Adobe Systems

Re: Premiere Pro lagging with H.264
by Lorenzo Ciuciat on Jul 23, 2017 at 8:26:17 pm

Hi, I hope to reply clearly to your question.
Following topics need to be know to understand the cause of the problem & the solution: stream, containter, index, transcode.

Adobe Premiere Pro cannot create a "transparent" index of raw H264 stream, so EVERY reposition in the timeline need a WHOLE reload the entire file (it doesn't matter if you go at the beginning, in the middle or at the end of the clip in the timeline). I have just verified this problem with APPRO 2017.1 using a raw 264 stream (without any container).

The simplest and faster solution is NOT TO TRANSCODE (any re-encoding of a stream modify the original stream: it can only become worste in quality) but to MUX the stream in a proper container. I usually use "FFMpeg" to do this task, with you HW specs you will be able to mux at OVER 1000 FPS (with a decent SSD).

You can use the following command to mux the single raw streams into a single muxed file:
ffmpeg -i video.264 -i audio.ac3 -vcodec copy -acodec copy muxed.mp4

Once muxed in the mp4 container via ffmpeg you can put it in the timeline in Premiere Pro and "VOIT LA" everything will be over 1'000x faster! (value based on a 13 GB raw h264 file: the bigger the file, the faster the index in the container will result).

Hope this will be useful for you. This cause can be self-checked using Microsoft (ex Sysinternals) "procmon" (Process Monitor) utility.

Lorenzo Ciuciat

Useful Links:

Re: Premiere Pro lagging with H.264
by Chris Wright on Jul 24, 2017 at 1:08:01 am

does the file size change with muxing? any quality loss? 10 bit support? if this works, then adobe should implement muxing instead of transcoding proxies.

Re: Premiere Pro lagging with H.264
by Duke Sweden on Jul 24, 2017 at 2:50:06 pm

I have ffmpeg properly installed. Still figuring out how to mux a file named, say "hello.mp4" (or, for that matter). I typed in your command ffmpeg -i video.264 -i audio.ac3 -vcodec copy -acodec copy muxed.mp4 and I get, in red, video.264: No such file or directory.

What would be the proper syntax? Also, if I have a folder with to, how would I mux the entire folder?

Re: Premiere Pro lagging with H.264
by Lorenzo Ciuciat on Jul 24, 2017 at 6:05:38 pm

but "mov" files are already muxed... they have VIDEO and AUDIO in the same files... 'right?

Re: Premiere Pro lagging with H.264
by Duke Sweden on Jul 24, 2017 at 7:13:42 pm

So does an mp4 file. I thought mux was a totally uncompressed file which, if I misunderstood you properly takes no time to transcode. So your "muxing" method is only to combine audio and video into one file?

Re: Premiere Pro lagging with H.264
by Lorenzo Ciuciat on Jul 25, 2017 at 12:06:26 am

exact: muxing with the 2 parameters I wrote before (-vcodec copy -acodec copy) simply put the same streams in the container so there is NO transcoding (and no quality loss... and max speed!)

Re: Premiere Pro lagging with H.264
by Sunderland Green on Nov 7, 2017 at 10:01:10 am

H.264 is an outstanding distribution format, But it is not a good editing format when you care about image quality, render speeds, or lots of effects work. Why Premiere Pro CC lags and skips when playing H.264 is that H.264 is mathematically intense. It takes some serious computer horsepower to decode its compression.