EL-Benjo

Q: Very slow even with instances.

Hi all, I am trying to compress a bunch of my own videos to save space. I have Compressor 4.2.2 on El Capitan 10.11.5, all latest software. My specs are:

iMac 5K Late 2015

4Ghz Quad Core i7, hyper threaded to 8 logical cores

32 Gigs RAM

AMD Radeon R9 M395X 4096 MB

 

I am exporting from H.264 source into MPEG-4 with H.264. I'm getting very slow times, and it gets even slower when I add one instance. I also edited the preference .plist file for compressor and added more instances than I was allowed by default as it was not maxing my CPU. Whether I have 1 instance (as compressor allows me) or 4 instances (which uses 90% of my CPU in activity monitor) it seems much slower than single instance. Why? My iMac is the highest end model, and has 8 logical cores, how can it be that its so slow in exporting when I use more instances? Its already really slow with just one instance. How can I speed this up?

iMac with Retina 5K display, OS X El Capitan (10.11.5)

Posted on Jul 3, 2016 3:18 AM

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Q: Very slow even with instances.

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  • by BenB,Helpful

    BenB BenB Jul 3, 2016 6:08 AM in response to EL-Benjo
    Level 6 (9,816 points)
    Video
    Jul 3, 2016 6:08 AM in response to EL-Benjo

    The Mac Pro is the highest end model.  When transcoding to H.264, do not use any instances.  The CPU has a built-in H.264 encoder that Compressor uses.  So instances tells Compressor to ignore that, and just do it via software encoding only.  The speed you get is the speed you get.  No knowing the duration of your videos, what their original format and codex are, nor how long they're taking, I've no way to tell if your Mac is slow, or if you're expecting too much from it.  That information would be helpful.

  • by EL-Benjo,

    EL-Benjo EL-Benjo Jul 3, 2016 6:08 AM in response to BenB
    Level 1 (12 points)
    Video
    Jul 3, 2016 6:08 AM in response to BenB

    1. I didn't know about the built in encoder, does that mean that all other codecs would benefit from multiple instances except for H.264?

     

    2. Never mind the setting I'm using, I'm not very good at this. What settings would you recommend for the following requirements:

    Up to 1080p video

    Small and standard video size for uploading and streaming

    Little as possible quality reduction

    As fast as possible encoding time considering the above

     

    I know it can be done because, well we all watch game of thrones and those video files go for an hour each and they're only like 500 Megabytes each or something. I just don't know how to compress my videos with the right settings for this situation.

     

    Thanks

  • by BenB,Helpful

    BenB BenB Jul 3, 2016 7:01 AM in response to EL-Benjo
    Level 6 (9,816 points)
    Video
    Jul 3, 2016 7:01 AM in response to EL-Benjo

    GOT uses proprietary compression tools the rest of us will never see, so you can't use that as a comparison. 

    The built-in encoder is H.264 only, it's something Intel put there.

    I'd just export ProRes 422 files and upload those.  Let the hosting site do the H.264 encoding for you.  They're going to re-encode anyway.  If you do export H.264, look in the Video Sharing Services group, for the HD 1080p preset.  That works pretty well.

     

    What codec/format/duration are the originals you're starting with?  Otherwise I have no clue what your "situation" is.

  • by EL-Benjo,

    EL-Benjo EL-Benjo Jul 3, 2016 7:05 AM in response to BenB
    Level 1 (12 points)
    Video
    Jul 3, 2016 7:05 AM in response to BenB

    Lemme give you the detes for one of the videos (the only thing that changes between my videos is their duration):

     

    File Size: 16.67 GB

    Duration: 1 hour and 16 minutes

    Type: MPEG-4 File

    Dimensions: 1920 x 1080

    Frame Rate: 29.97

    Video Codec: H.264

    Audio Codec: AAC

     

    As you can see, that file size is way too insane for storage, and I have like 20 of these videos I need to store. So I want to bring down the file size and not lose too much quality. Just to be clear, uploading them is not the main concern. Thats secondary. The main problem is storage on my hard drives. The videos are too big. They are all around an hour. I already had a look at the video sharing presets, they are still too big, if there are ways to further optimise the videos that would be good to know. My final concern is the amount of compression time. Thats basically the whole situation. Thanks

  • by BenB,

    BenB BenB Jul 3, 2016 7:45 AM in response to EL-Benjo
    Level 6 (9,816 points)
    Video
    Jul 3, 2016 7:45 AM in response to EL-Benjo

    OK, so you're starting off with H.264 files, which are already very highly compressed.  What we call a Long-GOP.  Means to read any single frame, all frames in the GOP (group of pictures, usually 8-12 frames), must be read.  So to read and re-encode each frame, the computer has to read 8-12 frames.  That eats up tons of time.  So going from H.264 to H.264 is not going to do anything but waste time.  You're not going to get much smaller for HD video.

     

    Not to mention Long-GOP formats don't hold their image quality through multiple generational transcoding.

     

    Now, if you formatted them to MPEG-2, standard definition, for DVD playback, you could get them under 3 or 4 GB.  But then you don't have HD video anymore, you lose image quality and resolution.

     

    I think you may be looking at more drive space.  But in the mean time, I'll find me an hour long H.264 file to play with, see what settings I can come up with.

  • by EL-Benjo,

    EL-Benjo EL-Benjo Jul 3, 2016 8:02 AM in response to BenB
    Level 1 (12 points)
    Video
    Jul 3, 2016 8:02 AM in response to BenB

    Thanks a lot my friend!

    PS don't be afraid to get technical, I do a lot of programming and development. I'm just uninformed about video compression.