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  1. Member
    Join Date
    Jan 2011
    Location
    poland
    Search Comp PM
    Hi,
    I have not noticed that before since I converted only short music videos recorded via HD PVR.
    This time I've been converting one long movie (more than 2hrs long) and what I see is not making me happy. When I started x264, the message (in cli window) was showing 25 fps, now - 7270 frames later it shows 10fps and still going down.

    Is there anything wrong with my laptop (there are no other programs running) or the syntax I'm using:

    Code:
    directShowSource("myMovie.ts", fps=25, audio=false, pixel_type="YV12")
    AssumeFrameBased()
    assumeTFF()
    crop(8,4,1904,1072)
    sharpen(0.2)
    fadeIn0(25).fadeIn0(25)
    fadeOut0(50).fadeOut0(50)
    and finally:
    Code:
    x264 --output outFile --crf 23 --preset slower --no-interlaced --direct auto script.avs"
    Thank you.
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  2. wild guess: beginning is easy to analyze and encoding is fast and as the scenes get more complex encoding slows down.
    (assuming cpu is not throttling because of overheating)
    Using LWLibavVideoSource instead of DirectShowSource might also help a bit if it's a decoding problem.
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  3. I'd agree. Re-encoding a studio logo or a bunch of frames with very little motion tends to be a lot faster than re-encoding the action in the middle of a movie. Often encoding speed will reduce relatively quickly, then settle down to something more consistent.
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  4. Banned
    Join Date
    Nov 2005
    Location
    United States
    Search Comp PM
    there is also this, filtering effects tend to propagate across frames, this applies to x264's built in deblocking filter as well as external filters like sharpen, depending on the size of the gop, reference frames used, b frames, et cetera it takes longer to perform the associated calculations.

    but i second looking at over-heating issues, a drop of that magnitude would raise red flags for me.
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  5. Member
    Join Date
    Jan 2011
    Location
    poland
    Search Comp PM
    Thanks all of you for your input.
    During encoding I was looking at Task Manager window (performance tab) to see if any clock speed / processor usage changes appeared - if that's the way I can check my cpu is not throttling. No such things happened (cpu 100% at 3.17 GHz; memory max 40%)
    Moreover I started temperature monitoring application where all the readings were almost steady:70 - 81 deg (average ~77)

    Now I understand the movie gets complicated, more and more calculations must be done but sooner or later fps settle down at some point:
    start ~ 25 fps,
    10000 - 9.9 fps,
    13000 - 9.6 fps,
    20000 - 10.5 fps

    I will check LWLibavVideoSource if there is any speed different.

    I also checked another approach (thought of it after deadrats post): I cut the movie on blank frames so I ended up with many shorter parts. I encoded 1st one but got very small speed gain.
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