Following up with an observation today. I'm finding that when I'm using Adobe Media Encoder to crop to 16:9 my 4096x2160 True 4K ProRes HQ file to make an HD 1920x1080 HD ProResHQ file with 8 channels of audio it is taking the 90 minute program 24 hours to process whereas when I did the same thing but had it Scale to Fit so there is a slight letter box that only took 3 hours. When I look at Activity monitor it's only showing AME using 90 percent or less of CPU %. That's less than one of the 12 cores but the system today while processing in the background is really sluggish like AME is taxing the computer. This is a 12 core MacPro mid2012 upgraded to 3.33GHz with 64 gig or ram and OS 10.8.5 running AME CC 2014.
Given the sluggish performance while doing the cropping file conversion and little CPU usage does that mean that AME is taxing my GPU a Radeon 5770 to do the cropping math? That would explain why everything is updating slowly. Just trying to see what the processing hog is when CPU usage is low for AME and everything else. If I pause AME the system does respond more normally. I'm even finding exporting a QT Ref from avid that is making an audio mixdown in the process is taking a crazy long time. Given Avid is all CPU why is it's internal processes being so hindered. Does whacking the GPU with AME really explain what I'm experiencing? Is there a way to monitor GPU usage similar to how you can monitor CPU usage in Activity monitor or some other app? Still wondering why scale to fit is sooooo much faster the cropping.
---In avid-l2@yahoogroups.com, <bigfish@...> wrote :
We have delivered the first 4K project to the facility that is making an IMF file from our 4096x2160 ProResHQ .mov with 8 channels of audio. All is well yesterday I took the 550GB file into Adobe Media Encoder to make an HD version. Using no cropping but set to scale to fit and a target raster size of 1920x1080 there is a small letter box top and bottom, which is to be expected given the true 4K is 1.89 not 1.77 aspect ratio. AME baked out the file in about 2.75 hours. I then set the same process only cropping the original file to file correctly into 16:9 with no letter box, cropping off the wings left and right. Left this cooking over night only to find today it will take 24 hours or so. I had other elements in the batch that had finished but when I cam in this file was about half done after 10 hours. I shut it down then restarted ame after clearing all but the 4K file with the cropping from the Que. I restarted and it then said the whole thing would take 12 hours and the preview monitor appeared to be moving faster. This was a new encode not a pickup of the one I aborted overnight. I stopped the process again and did a full system restart thinking that might make things go even faster but now it says 24 hours for the bake time again and I've tried several restarts.
I'm wondering why when I did the first restart it seemed to be working about twice as fast as all the other restarts. Is that just computer voodoo and it was probably just miscalculating the estimated time and would have crept up the estimated time as it baked? Just curious what others think.
The real question is why is there such a discrepancy between scaling to fit with a Letter Box and cropping? I would think scaling to fit would take more time than just cropping but clearly that is not the case. By cropping I would think it's just ignoring the edge pixels and doing in essence a .25 scale down of the pixels to fit into a normal HD raster 1920x1080. I would think that would be similar math to the scale to fit so why such a big diffenece that takes 8 times as long to crop than to scale. I must be oversimplifying the actual algorithms that are being used or something in the overall process. Any insight would be welcome.
John Moore Barking Trout Productions Studio City, CA bigfish@...
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