Author Topic: exact fps: can I change H264 metadata in post without transcoding?  (Read 9608 times)

ADJ

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I have some H264 footage shot yesterday on a 50D, 5D2 and 60D. I want to edit in Lightworks. The 50D footage was shot with fps override set to 25fps which is what the other cameras were set at. Lightworks erroneously reports the 50D footage as 30fps since that's what the metadata says. I can't get the 50D footage to import into Lightworks without transcoding the mov files which is time consuming.

Is there any freeware which will change the metadata in post without transcoding everything? Maybe there's a global setting or if the first frame is changed to 25fps maybe the software will accept it?

On Windows I can transcode with Eyeframe Converter http://www.videohelp.com/tools/EyeFrame-Converter
or WinFF http://winff.org/html_new/downloads.html
or Shotcut http://www.shotcut.org/bin/view/Shotcut/WebHome

If transcoding is necessary, what would be the best setting to use in terms of speed without degrading the video too much?

I did a search through the forum but the nearest I could find was this:

http://www.magiclantern.fm/forum/index.php?topic=7038.0

Is everyone on the 50D shooting raw all the time or does anyone shoot H264?

ADJ

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Re: exact fps: can I change H264 metadata in post without transcoding?
« Reply #1 on: February 15, 2014, 10:34:30 PM »
In case it's useful for someone else I tried this workaround which seems to work on windows 7 x64:

demux the .mov from the camera to m2ts using tsMuxeR http://www.videohelp.com/tools/tsMuxeR

mux the resultant m2ts file using MkvToMp4 http://www.mediafire.com/download/1a0oc04u539b5eg/MkvToMp4_0.224.zip

if you double click on edit track it lets you change the fps to 25.

The m4v file which results will import into Lightworks and displays as 25fps.

This is a LOT faster than transcoding.

There has to be a better way.

ADJ

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Re: exact fps: can I change H264 metadata in post without transcoding?
« Reply #2 on: February 17, 2014, 12:39:09 AM »
I found the above method didn't work with some of my files so after a bit more looking found MyMP4box gui
 http://www.videohelp.com/tools/My-MP4Box-GUI

I had trouble installing it on my w7 x64 system but got it working once it was installed in c:\Program Files (x86)\

as described on http://forum.videohelp.com/threads/329598-Can-t-open-up-My-MP4Box-right-after-installation

Once working, this allows very speedy demuxing of the 50D mov files made with exact fps override. These can be changed from 30 fps to one of the presets (15, 23.976, 24, 25, 29.970, or 30fps) before muxing to mp4 without transcoding.

Lightworks http://www.lwks.com/ seems to accept these mp4 files once the fps issue is sorted out and reports them as 1920 x 1080 rather than 1920 x 1088. Hopefully lightworks will relent in the future and go back to allowing output greater than 720p for free.

Sorry to be replying to my own posts but maybe it will speed someone else up in the future. Thanks to everyone on these boards for their contributions.

pilgrim

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Re: exact fps: can I change H264 metadata in post without transcoding?
« Reply #3 on: February 17, 2014, 01:32:20 AM »
ADJ,

Thanks for sharing the solution of your problem. I try the program as you mention, MyMP4box gui, and it's true very fast.
For conversion of file H.264 from Canon or AVCHD Sony I am used with :
- WinFF for converting MP4 off-line (2Mbps).
- Eye-Frame for converting to MPEG Intra-Frame, for editing on Lightworks on Win7 64b.
- Shotcut for converting to MPEG Intra-Frame with stabilization, or many other correction.
I use also Shotcut on Mac Mavericks for converting to ProRes with basic correction, before edit it on Final Cut Pro.
For me Shotcut give very good result, seen on iMac 27", and the new stabilization is great. Working only in Play-list is very fast. And the timeline is promising.
The good news is that Lightworks 11.5 now use codec ffmpg, free version also, so we don't need transcode any more. I tried to edit directly the file Mov from Canon and AVCHD, it doesn't need to transcode, just link. That is a game changer.
greetings.


vascostmr

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Re: exact fps: can I change H264 metadata in post without transcoding?
« Reply #4 on: April 07, 2015, 04:57:45 PM »
I've been searching for a simple and efficient way of changing the FPS of the .MOVs taken with my 50d. The best ' made it so far is this:

MOV (30fps) --> raw h264 stream --> MP4( 24fps)
Code: [Select]
ffmpeg.exe -i IMPUT.MOV -codec copy -bsf:v h264_mp4toannexb track1.h264
mp4box.exe" -add track1.h264:fps=24 -new OUTPUT.mp4

Anyone with a better/faster way?

erik763

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Re: exact fps: can I change H264 metadata in post without transcoding?
« Reply #5 on: June 05, 2015, 12:34:37 AM »
Hi guys !!

I'm new to the world of ML - i've just hacked my 50D and started experimenting with h264 and raw video. I came across this problem with h264 video and FPS override set to 23.976 -> after opening the .mov in VLC it looks faster then in real life + metadata says 30fps ... this is the problem you are discussing here right?

Is there any easy way (for amateurs) to play & edit @ 24 fps on mac?

Thanks !