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Editing an important movie without losing quality


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#1 Shasoosh

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Posted 29 June 2012 - 08:26

I got a 1080p m2ts file that i want to edit (just to cut a few parts from it)
What's the best easiest way i can do it without loosing 0.001 % of quality?


#2 HawkMan

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Posted 29 June 2012 - 10:16

Not save as a lossy compressed format after the edit. which means you need a LOT of space. Though I doubt you'd ever be able to notice the difference between that and a well encoded MP4

#3 OP Shasoosh

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Posted 29 June 2012 - 10:19

Right now it's a 32 gigs m2ts and trying to edit it with vegas took for ever. What software i should use to get best fastest results?

#4 HawkMan

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Posted 29 June 2012 - 10:24

Doesn't matter, the software won't have any effect on the end quality, only the compression chosen for the final output will.

#5 Elliot B.

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Posted 29 June 2012 - 11:53

Any edit will require a re-encode.

#6 OP Shasoosh

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Posted 29 June 2012 - 11:58

I know there are softwares that can trim and to simple cut & paste edit on mkvs without re-encoding (the process takes a few seconds) Isn't there something like that for m2ts?

#7 mikiem

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Posted 29 June 2012 - 13:41

m2ts is a container, e.g. on a Blu Ray disc it holds video, audio, & subs. Google/Bing on your source -- where you got the original m2ts file -- for more info on your particular video file. You can strip (DeMux) the individual streams from the m2ts file, then work with the video & audio separately -- that may be the way to go depending on the format of the individual streams -- use MediaInfo with the m2ts to find out what format audio & video are inside, then Google/Bing on editing those formats. Once you know the actual audio & video formats you can also find out if you if you can edit without re-encoding & quality loss... most current formats use keyframes [I frames etc.] which are complete frames, then store just changes to the picture between those keyframes -- depending on the video's format you may be able to find software that'll perform cut edits, i.e. split/join the video at keyframes, re-writing & re-indexing the video file. Sometimes the best route [workflow] is to convert your video to near lossless avi before editing/re-encoding -- the UT codec can work Very well for that.

Notes: If you demux the video stream, you may have to put it into another type of container to work with it, depending on the format & the software you want to use, e.g. putting it inside .mkv, .avi, .mov etc. Audio may have to be converted to .wav, or .w64 etc. before you can do much with it, then re-encoded after editing to your desired format -- a lot of software will convert to .wav behind the scenes, e.g. create a .wav file in your Temp folder, work with that, then re-encode the output or result -- if your software does that be careful you're not bouncing around from one format to another more than necessary, losing a bit of quality each time. Depending on the source of your original m2ts file, you may or may not have problems getting whatever software to work with it -- if that's the case there are a few repair type utilities you can try, that re-write the file without re-encoding, adding/removing flags, re-indexing etc. [check videohelp.com for app links/downloads]. Ffdshow & LAVFilters might help your system deal with some of the more difficult video formats like AVC & VC1, but be careful because anything you add in the way of Direct Show filters & codecs etc. can have undesired side effects on video handling elsewhere in Windows &/or software.

On Vegas... Sony apps like indexed video, e.g. mpg2 as .mpg rather than .m2v, & .m2ts rather than .avc/.264. They can however choke on AC3 & won't take .dts -- trying to feed Vegas audio in a format it doesn't like can make everything take forever. Vegas Pro 9 will let you edit mpg2 without re-encoding, but that's broken in v. 10 & 11 -- note that if you have 9 & 10 or 11 installed, all versions will use the latest encoder, so it has to be v. 9 only. Vegas is really ideal OTOH for working with, & if needed re-syncing your audio... if/when you work with AVC for example, depending on the software you use it's real easy to very slightly shorten the video file, throwing video/audio sync off -- Nero 10 & 11 have a bad habit of doing that shortening if you feed it AVC/H264 video. Badass Viking said: "... software won't have any effect on the end quality", & that's almost always correct -- think of Vegas always following some internal scripting, so it's very possible to have Vegas convert or transform a video, then convert/transform it back before output/encoding... that both slows things down & hurts quality. Be very careful how your Vegas project is set up -- if your video's 23.976, your project has to be at 23.976, not 24 fps -- the same sort of thing applies to frame size, aspect, color space & so on. Vegas also works with, likes RGB, so if you wind up going to an intemediate format before importing the video, you might want to go to RGB vs. YUV. If you do encode in Vegas 11, be aware that GPU-based hardware acceleration can make encoding a bit flaky, depending on video formats, whether you have it turned on in Vegas or not -- try 32 & 64 bit versions, try acceleration on/off [separately in Vegas preferences & in the encoder set up if avail.], try Virtu if you have it on/off, & maybe try different graphics card driver versions [I don't know if the driver version effects Nvidia with Vegas, but with ATI it can].

Finally: "Right now it's a 32 gigs m2ts and trying to edit it with vegas took for ever. What software i should use to get best fastest results? " Bouncing from one drive to another helps, better yet if you're reading the original video on the timeline from a SSD, then write the encoded output to another drive. Check Windows' Task Mgr. for processes you don't want/need running, making sure your AV software isn't showing CPU use at the same time. Otherwise Vegas Pro 11 is pretty fast -- AVC 1080p encoding happens for me at roughly real-time, while mpg2 takes half as long [or less]... at any rate on this rig it's faster encoding than anything I've found with the exceptions of X264 [AVC/H264 encoder] set to minimum quality [it's much slower set to higher quality comparible to Vegas], or VirtualDub encoding to avi using the UT codec I mentioned.

#8 Tjcrazy

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Posted 29 June 2012 - 14:14

Try Avidemux.


You can use it to cut clips from files, then encode those clips too a format.

I've been doing some video edits (fanvids ;/) recently. I converted all my Dr Who episodes to MJPEG codec, PCM audio codec and AVI video container.

Most of these have been 720p, and they've edited fine in Sony Vegas Pro!