Resolved poor 4K performance on my 6-core trashcan

[seenew]

Hey guys,

I recently purchased a new Mac Pro at work as a long overdue upgrade to my aging iMac from 2011. The project that pushed me over the edge is a series of time lapses I shot a couple of weeks ago which will be compiled into five 4K video files. Each time lapse is about 4000 10MP raw images, so it's got a lot of data to crunch.
I expected even with this power (see attached specs), the machine would still chug along to export 4000 raw files, but I did not expect issues with playback once everything is compiled.

I exported the sequence in 4K, 3K, and 1080P. The 4K plays smoothly for few seconds and then starts to skip and then falls apart altogether. 3K is a bit better, but still struggles. 1K plays all the way through, but won't scrub very well. I don't get that, especially the last part.

The file specs for the 1K and 4K file are also attached.

I'm not even playing them on a 4K monitor.

Any ideas what the issue could be?

(PS: I'm using Lightroom 5 and LR TimeLapse 4 to compile the shots)

 

[Inutopia]

LOL DAT BITRATE

Edit: Sorry, I don't know what came over me there! I think your bit rate might be a bit high there my man. Try lowering it when you make the 4k file and it should play swimmingly

 

[h9826790]

Same suggestion. Over 200Mbit/s is too much.

With proper encoding, even 20Mbit/s can produce very good image already (tested on my 84" 4K TV).

You may try to set the bit rate to 80, I personally believe which is already more than enough. In fact, I can hardly tell the difference once over 30.

If still have problem. It seems 60 is a good number for you.

For 1080P, 20 should be more than enough.

 

[seenew]

As soon as I posted the screenshots, the bitrate occurred to me.
Thanks for confirming the suspicions! I'll give it a shot.
(and maybe post the results when all is said and done!)

Cheers guys!

 

[rkuo]

What are you testing playback in?

 

[seenew]

What are you testing playback in?

quicktime and VLC

 

[larrylaffer]

LOL DAT BITRATE

Edit: Sorry, I don't know what came over me there! I think your bit rate might be a bit high there my man. Try lowering it when you make the 4k file and it should play swimmingly

Same suggestion. Over 200Mbit/s is too much.

With proper encoding, even 20Mbit/s can produce very good image already (tested on my 84" 4K TV).

You may try to set the bit rate to 80, I personally believe which is already more than enough. In fact, I can hardly tell the difference once over 30.

If still have problem. It seems 60 is a good number for you.

For 1080P, 20 should be more than enough.

You people are nuts. A Mac Pro, or pretty much any SSD-based Mac should have no problem playing back up to 400+ Mbps H.264. How do I know this? I regularly edit AVC-Ultra footage on a Mac Pro, which is (da da da) 440Mbps H.264

440Mbps translates to about 55MB/sec (not including audio, which adds about 2MB/sec). That's megaBYTES per second, not megaBITS. For reference, the Blackmagic Disk Speed Test on a new Mac Pro will read/write to a Mac Pro's SSD at over 700MB/sec.

So, the data rate is NOT the problem. Perhaps it's the encoding itself? Do you know what your H.264 parameters were, such as the number of b-frames, etc.?

 

[ProjectManager101]

I may be a little ignorant here but what kind of drive if he using? And I believe no every playback software or codec uses all the ram or resources equally, probably allocating more memory. I do not know, just a wild guess.

 

[seenew]

So, the data rate is NOT the problem. Perhaps it's the encoding itself? Do you know what your H.264 parameters were, such as the number of b-frames, etc.?

I don't know the specific H264 parameters-- LR TimeLapse doesn't really let you mess around much with the settings. It doesn't actually let you specify bitrate, even-- just quality settings like low, medium, high, very high, and ultra high. Very high is where I got my results from for the 4K export.

I could figure out how to render the video using AfterEffects but I don't have the time to learn that right now.

I may be a little ignorant here but what kind of drive if he using? And I believe no every playback software or codec uses all the ram or resources equally, probably allocating more memory. I do not know, just a wild guess.

I'm reading the file off the internal flash drive.

 

[radiotamarillo]

Yes, it's those unknown H.264 encoding parameters.

Try rendering/exporting the sequence to ProRes 4444 or 422 HQ.

 

[larrylaffer]

Yes, it's those unknown H.264 encoding parameters.

Try rendering/exporting the sequence to ProRes 4444 or 422 HQ.

This is good advice. ProRes 4444 will provide stunning image quality. The bitrate will be high, but your system should have no problem playing it back in realtime.

 

[rkuo]

VLC is very poor at hi res accelerated playback. Quicktime is more representative. ProRes is also good if your IO can keep up (sounds like it should be able to).

 

[seenew]

Thanks everyone, ProRes worked like a charm!