[FFmpeg-user] Need help; willing to pay

Steve Boyer steveboyer85 at gmail.com
Wed Jan 6 05:50:18 CET 2016

On Tue, Jan 5, 2016 at 10:15 PM, Matthew Adams <matthew at matthewadams.me> wrote:
> Moritz & Steve,
> Thanks for your ffmpeg commands.  On my MacBook Pro Retina 15", I ran them
> (took less than 30 secs or so) and then viewed the resulting files in both
> VLC & QuickTime.
> Both of the resulting videos did *exactly* what I was trying to get rid of:
>  a second or so of real-time action at the beginning, then a long super
> slow-motion middle, then a second or so of real-time action at the end.

One quick sanity-check -- are you running the commands on
"variable-bitrate-sample.mov" or on the raw
"Jan22016-150PM-b6cs7K.mov"? I downloaded all three files and here are
the commands used (jumped back to the linux side with an older version
of FFmpeg compiled [built on Nov 16 2014 15:41:37 with gcc 4.8 (Ubuntu
4.8.2-19ubuntu1], but should still work in newest version):

ffmpeg -i Jan22016-150PM-b6cs7K.mov -c:a copy -c:v libx264 -vf
fps=fps=30 -crf 20 -preset slow Jan22016-150PM-b6cs7K.mp4
ffmpeg -i Jan22016-151PM-g8drtF.mov -c:a copy -c:v libx264 -vf
fps=fps=30 -crf 20 -preset slow Jan22016-151PM-g8drtF.mp4
ffmpeg -i variable-bitrate-sample.mov -c:a copy -c:v libx264 -vf
fps=fps=30 -crf 20 -preset slow variable-bitrate-sample.mov

Running the FFmpeg commands, I get:
...150PM... filesizes: MOV: 61M, MP4: 8.9M
...151PM... filesizes: MOV: 27M, MP4: 3.9M
variable... filesizes: MOV: 11M, MP4: 14M

"150PM" and "151PM" are both in real-time, audio preserved, in 30fps
wonder (easy to change this to 60 fps if you desire by mucking around
in the commands above). The "variable" file does not have audio and
plays for a few seconds in realtime, then goes into slow-motion.

> I just want the whole video to be in real time.  Size is of secondary
> concern.  Interestingly, QuickTime actually *shows *where the three
> sections are with two delimiters -- I wish I could show you the screen
> shot, but I can't get a screen shot of the QuickTime controls overlay (it
> keeps disappearing).  Even more interestingly, VLC plays some of the videos
> choppily but in real time with no slow motion; QuickTime shows the
> different frame rates, but lets me speed things up to real-time.  I admin
> to being at a bit of a loss to determine why VLC is in choppy real-time &
> QuickTime always honors the recorded frame rates.
> Any more suggestions/sample commands?  Will I need to cut the real-time
> portions out, then convert the middle slo-mo to match the real-time
> portions' frame rates, then concatenate the three parts all back together?
> If so, how do I (1) find the 2 spots to cut at, (2) actually cut the file
> into 3 parts, (3) convert the slo-mo to real-time, then (4) concatenate
> them all back together again?
> -matthew
> PS: FWIW, with a 10.7 Mb original video, Steve's command resulted in a 13.7
> Mb video, Moritz's, 9.3 Mb.
> On Tue, Jan 5, 2016 at 8:52 PM, Steve Boyer <steveboyer85 at gmail.com> wrote:
>> On Tue, Jan 5, 2016 at 6:56 PM, Andy Furniss <adf.lists at gmail.com> wrote:
>> > Matthew Adams wrote:
>> >>
>> >> On Tue, Jan 5, 2016 at 3:07 PM, Moritz Barsnick <barsnick at gmx.net>
>> >> wrote:
>> >>
>> >>> Anyway, it should be possible to convert those to something sane.
>> >>> As Carl Eugen mentions: What's your goal?
>> >>>
>> >>
>> >> My goal is to convert these videos a fixed, relatively standard (30
>> >> fps? 60 fps?) frame rate while retaining the highest image quality
>> >> possible so that pretty much any playback hardware & software can
>> >> play them normally. Bonus for preserving audio as well in the
>> >> converted videos.
>> >
>> >
>> > Well I am impressed that a phone can record 240fps.
>> >
>> > Personally I would go for 60 fps, fast paced stuff looks terrible @30fps.
>> >
>> > I suppose it depends on what you intend to play it on.
>> >
>> > If the quality is too low for you you can always get higher bitrates
>> > with eg. -crf 20.
>> >
>> > FWIW testing the master direct mpv by default does a good job playing it
>> > on my PC.
>> >
>> > _______________________________________________
>> > ffmpeg-user mailing list
>> > ffmpeg-user at ffmpeg.org
>> > http://ffmpeg.org/mailman/listinfo/ffmpeg-user
>> Tested on the windows 10 side of my laptop with the command:
>> "C:\Users\Steve\Desktop\ffmpeg-20160105-git-68eb208-win64-static\bin>ffmpeg
>> -i C:\Users\Steve\Desktop\Jan22016-150PM-b6cs7K.mov -vf fps=fps=30
>> -c:a copy -vcodec libx264 -crf 20 -preset slow asdf.mp4"
>> and it spits out a fixed frame rate 30fps video and looks purdy. VLC
>> plays it no problems. This will preserve the audio feed exactly, and
>> only re-encodes the video using x264 at a pretty decent quality. Final
>> size is 9 MB.
>> Steve
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