PDA

View Full Version : m2t or mov? quality issues?




adelchi
Jul 28, 2010, 09:41 AM
Hi all,
I am new to this forum (where I already found some very interesting information) and also new to video.
I understood that m2t is a native HDV type of file but can't be used on a Mac, and if I capture a tape with FCP I will get a mov file (uncompressed and lossless as the m2t, am I right?).

1)but, I was wondering, why the mov is heavier than the m2t? eg, my mov is about 500mb per minute, while the m2t (captured on a pc using Edius 5) is about 200mb per minute

2) it is then better to capture the tape on a Mac or I get the same quality on a pc?

thank you!



huntercr
Jul 28, 2010, 10:20 AM
Hi all,
I am new to this forum (where I already found some very interesting information) and also new to video.
I understood that m2t is a native HDV type of file but can't be used on a Mac, and if I capture a tape with FCP I will get a mov file (uncompressed and lossless as the m2t, am I right?).

1)but, I was wondering, why the mov is heavier than the m2t? eg, my mov is about 500mb per minute, while the m2t (captured on a pc using Edius 5) is about 200mb per minute

2) it is then better to capture the tape on a Mac or I get the same quality on a pc?

thank you!

The mac mov (container ) is in the Apple Intermediate Codec... it's less compressed than the m2t file ( which is HDV format... aka MPEG2 )

Capturing digital is capturing digital... you won't get any less quality going through the Mac and you won't get any more quality except that you'll be editing in a less compressed manner on the Mac, but presumably any editor on a PC that can edit native HDV will handle it in a lossless way. ( and it's probably decompressing it in place behind the scenes anyway without you knowing )

The larger file size/lower compression rate for the .mov file, in this case just means faster rendering for effects, shuttling through footage etc. So whatever you want to do is fine.

Someone else may want to weigh in on this... I'm not 100% certain how HDV is handled on Popular PC editors

kev6677
Jul 30, 2010, 07:14 AM
it's so amazing to see this nonsense about apple's AIC or MOV files being equal to or superior to m2ts, does these posters actually own a camcorder that outputs to m2ts or do they even own a mac???

the thruth of the matter is m2ts files converted to any other format other than m2ts results in a significant loss of video quality. it may not be that noticeble on a tiny imac screen but try watching it on your 40 inch plasma and you will see what i mean.Can't believe apple cannot get this right espescially when HD is the video standard.

if you want the best video quality AVCHD (m2ts) format from your camcorder stick with windows converters which can edit AVCHD files nativelly.

spinnerlys
Jul 30, 2010, 07:27 AM
it's so amazing to see this nonsense about apple's AIC or MOV files being equal to or superior to m2ts, does these posters actually own a camcorder that outputs to m2ts or do they even own a mac???

the thruth of the matter is m2ts files converted to any other format other than m2ts results in a significant loss of video quality. it may not be that noticeble on a tiny imac screen but try watching it on your 40 inch plasma and you will see what i mean.Can't believe apple cannot get this right espescially when HD is the video standard.

if you want the best video quality AVCHD (m2ts) format from your camcorder stick with windows converters which can edit AVCHD files nativelly.

Do you even know what AIC and MOV is?

I agree, that it is a shame, that Mac OS X does not support native AVCHD editing, but if you are really into editing, it is best to use less compression than AVCHD does.

We recently edited XDCAM footage (MPEG-2 (not -4), AVCHD is using an MPEG-4 variant too) in its native codec, with an AMA wrapper in Avid on a Mac Pro. Playback was fine, but as soon as you wanted to scrub through the footage, the Avid got much slower, due to the CPU decoding the MPEG-2 video. If the footage would have been transcoded to an editing format and codec, no such thing would have happened. As it also was multi-cam, the preview of groups was sometimes abysmal, a Power Mac (2004) was faster in viewing and editing SD groups with up to seven cameras than a 2008 Mac Pro editing HD groups with two cameras, just because it was still using MPEG-2 as a codec.

Ritsuka
Jul 30, 2010, 07:47 AM
Loss of quality? Maybe a bit if you are using iMovie and transcoding to AIC.
But m2ts and mov have nothing to do with the video quality, because they are just container format that can store the same bit exact video track.
m2t is not the native hdv file type. Neither is mov. But m2t and mov are just two way to store the data on the computer with the same quality.
I don't know if you can edit hdv natively in iMovie, but in Final Cut Pro you can edit HD, HDV, XDCAM HD & EX, AVC-Intra natively without and video conversion.
But obviously editing an H.264 video track (AVCHD and AVC-Intra are just H.264), it's like editing dv on 20 years old computer.

adelchi
Jul 30, 2010, 01:59 PM
The mac mov (container ) is in the Apple Intermediate Codec... it's less compressed than the m2t file ( which is HDV format... aka MPEG2 )

Capturing digital is capturing digital... you won't get any less quality going through the Mac and you won't get any more quality except that you'll be editing in a less compressed manner on the Mac, but presumably any editor on a PC that can edit native HDV will handle it in a lossless way. ( and it's probably decompressing it in place behind the scenes anyway without you knowing )

The larger file size/lower compression rate for the .mov file, in this case just means faster rendering for effects, shuttling through footage etc. So whatever you want to do is fine.

thank you hunter, I think I got it now... hopefully :)

Loss of quality? Maybe a bit if you are using iMovie and transcoding to AIC.
But m2ts and mov have nothing to do with the video quality, because they are just container format that can store the same bit exact video track.
m2t is not the native hdv file type. Neither is mov. But m2t and mov are just two way to store the data on the computer with the same quality.

yup, just containers... but why such a difference in file size??

spinnerlys
Jul 30, 2010, 02:07 PM
yup, just containers... but why such a difference in file size??

Because of the CODEC (http://en.wikipedia.org/wiki/Video_codec).

As AVCHD camcorders use an MPEG-4 codec variant, the image is compressed very much and not every frame (25 or 30 frames per second) is stored using this codec, to keep file size and read and write speeds low.

AIC and all the other editing codecs store every frame as uncompressed as they are programmed for, thus the bigger file size.


CONTAINER (http://en.wikipedia.org/wiki/Container_format_(digital))

LethalWolfe
Jul 30, 2010, 02:23 PM
Hi all,
I am new to this forum (where I already found some very interesting information) and also new to video.
I understood that m2t is a native HDV type of file but can't be used on a Mac, and if I capture a tape with FCP I will get a mov file (uncompressed and lossless as the m2t, am I right?).
What you shoot on your camera is very compressed and very lossy just so you know.


it's so amazing to see this nonsense about apple's AIC or MOV files being equal to or superior to m2ts, does these posters actually own a camcorder that outputs to m2ts or do they even own a mac???
Your post is completely inaccurate which makes your condescending tone that much more amusing.



yup, just containers... but why such a difference in file size??
How are you capturing HDV on the Mac? Are you capturing it as HDV, ProRes, AIC...?


Lethal

kev6677
Jul 30, 2010, 05:01 PM
I have all read all about .mov just being a container and AIC being a losslless file format .However edited AVCHD videos to either format are terrible if you don't believe me go ahead and convert to either format then play it back on your HDTV the result looks like an upconverted dvd and not that pristene HD some of us are use to.

LethalWolfe
Jul 30, 2010, 05:31 PM
I have all read all about .mov just being a container and AIC being a losslless file format .However edited AVCHD videos to either format are terrible if you don't believe me go ahead and convert to either format then play it back on your HDTV the result looks like an upconverted dvd and not that pristene HD some of us are use to.
.mov is just a container (not a format) and AIC is not a lossless codec. AIC is also old and Apple's apps used to have a problem w/it properly transcoding interlaced footage (maybe Apple fixed this, I don't know 'cause I never used nor really paid attention to AIC). There is also an option if you are using iMovie to import 1080i video at half res which will obviously look bad. With all that being said AIC is a much less compressed codec than HDV or AVCHD.

Going back to what you said before:
the thruth of the matter is m2ts files converted to any other format other than m2ts results in a significant loss of video quality.
That is completely false. Transcoding AVCHD (or HDV or XDCAM EX, etc.,) into, say, ProRes (which is standard procedure in a FCP based workflow) is not going to result in any image quality loss unless you screw it up. Transcoding AVCHD into one of Avid's DNxHD finishing quality codecs will not result in any quality loss unless you screw it up.


Lethal

kev6677
Jul 30, 2010, 05:44 PM
lethalwolf wrote: That is completely false. Transcoding AVCHD (or HDV or XDCAM EX, etc.,) into, say, ProRes (which is standard procedure in a FCP based workflow)




Say what..... more codec's more conversion and may I ask what device plays backs these codec formats you claim??????...Most user want a simple way to edit and view there HD footage(on there HDTV) not some complicated mess requiring hundreds of dollars more in software or special equiptment to play back HD video...apple sucks for hd video editing.

spinnerlys
Jul 30, 2010, 05:57 PM
lethalwolf wrote: That is completely false. Transcoding AVCHD (or HDV or XDCAM EX, etc.,) into, say, ProRes (which is standard procedure in a FCP based workflow)




Say what..... more codec's more conversion and may I ask what device plays backs these codec formats you claim??????...Most user want a simple way to edit and view there HD footage(on there HDTV) not some complicated mess requiring hundreds of dollars more in software or special equiptment to play back HD video...apple sucks for hd video editing.

What exact editing application have you used then to edit HD in Mac OS X?

If you have used iMovie, have you made sure to set the resolution to full before import?

http://i25.tinypic.com/4vfkt5.png

I have used ProRes and AIC in my encounters with Apple editing software for HD footage, my experience is limited though, as I use Avid (on Mac OS X) much more. I have not encountered any visible image quality loss during any of my transcoding process, unless I screwed them up via wrong settings.

As AVCHD footage is quite loss from the beginning and if you have a trained eye, you can see "bad" image quality even in the source footage which will stay even if you transcode to a better codec and container.

And Apple doesn't suck for HD video editing, otherwise not that many would use Mac OS X for doing that exact same thing, especially those consumers Apple is after.

Btw, you can quote someone via the http://forums.macrumors.com/images/buttons/quote.gif button on the bottom right of the post you want to quote.

kev6677
Jul 30, 2010, 06:12 PM
Did you play your edited video back on an HDTV( very important) not your computer screen... if so you will see the loss of picture quality compared to if you played the same file using the original m2ts format.

As for settings all my videos are imported using "full 1920 by 1080" unfortunatelly the finished product never looks like the original....very sad apple needs to fix this fast or risk users sticking to windows for there HDvideo needs.

spinnerlys
Jul 30, 2010, 06:24 PM
Did you play your edited video back on an HDTV( very important) not your computer screen... if so you will see the loss of picture quality compared to if you played the same file using the original m2ts format.

As for settings all my videos are imported using "full 1920 by 1080" unfortunatelly the finished product never looks like the original....very sad apple needs to fix this fast or risk users sticking to windows for there HDvideo needs.

I don't remember if I played it back via an HDTV, it was two to three years ago and we edited in a hurry. I only had an SD control monitor and it looked fine on it, but it was down-scaled, thus no real comparison.

Btw, I was talking bollocks when I mentioned XDCAM being MPEG-4, it is MPEG-2. Nonetheless it is CPU intensive.

Btw 2, how did you get your video from iMovie to the TV?

huntercr
Jul 30, 2010, 06:34 PM
lethalwolf wrote: That is completely false. Transcoding AVCHD (or HDV or XDCAM EX, etc.,) into, say, ProRes (which is standard procedure in a FCP based workflow)




Say what..... more codec's more conversion and may I ask what device plays backs these codec formats you claim??????...Most user want a simple way to edit and view there HD footage(on there HDTV) not some complicated mess requiring hundreds of dollars more in software or special equiptment to play back HD video...apple sucks for hd video editing.

Dude, you need to step back a little and learn. LeathalWolfe knows his stuff. There are some people on here who are professionals. ( I'm not one of them, I've just been around the block a couple times )
ProRes is not a distribution codec... it's for editing. When you're done you export to a suitable codec. ( MPEG2, MPEG4, H.264, etc... )

You are passionate about what you do know. I admire your spunk. Keep an open mind, there's always something to learn in all walks of life.

LethalWolfe
Jul 30, 2010, 06:54 PM
Say what..... more codec's more conversion and may I ask what device plays backs these codec formats you claim??????...Most user want a simple way to edit and view there HD footage(on there HDTV) not some complicated mess requiring hundreds of dollars more in software or special equiptment to play back HD video...apple sucks for hd video editing.
Okay, I see where the disconnect is. You are meaning to only talk about consumer-level gear but you are making giant blanket statements and I am correcting you because in terms of a prosumer or professional perspective what you are saying is incorrect.

Just an FYI, the vast majority of what you watch on TV and see in movie theaters is cut on Apple hardware and/or software. And if an AVCHD camera was used for acquisition it sure as heck was transcoded into a high-quality codec for post production.


Lethal

kev6677
Jul 30, 2010, 07:43 PM
I appreciate the constructive input from Spinnerlys and lethalwolf I love apple products however i find there complacency to the average consumer who uses AVCHD dissapointing to say the least. I really hope they come up with a real solution why should I spend $1500 on a computer and still have to spend another couple humdred more just to edit my HD home movies . It's not like AVCHD is some unknown format. Almost all CONSUMER camcorders use this codec and we bought HD camcorders because we want pristene HD quality footage and not a dvd upconverted substtute ".MOV or AIC"


In responce to how i got my HD video to my HDTV i had to spend more money for software to convert to a fomat that was compatable with my bluray player. if I remember correctlly the format was H264

spinnerlys
Jul 30, 2010, 07:48 PM
In responce to how i got my HD video to my HDTV i had to spend more money for software to convert to a fomat that was compatable with my bluray player. if I remember correctlly the format was H264

Do you remember which software? Was it by any chance Toast Titanium, which is capable of burning Blu-Ray encoded video to a normal DVD, thus Blu-Ray players can read them as "Blu-Rays"?

kev6677
Jul 30, 2010, 07:58 PM
Actually no i used a program called "Ifunia video converter" works really fast i have an Imac 21.5" with 3.33ghz core2duo processor & 4gb of ram. Finished video quality is lacking though not as good as original m2ts file.

Ritsuka
Aug 1, 2010, 02:22 AM
So you use uber crappy software and then whine about the quality? :rolleyes:

spinnerlys
Aug 1, 2010, 12:04 PM
Actually no i used a program called "Ifunia video converter" works really fast i have an Imac 21.5" with 3.33ghz core2duo processor & 4gb of ram. Finished video quality is lacking though not as good as original m2ts file.

Maybe the crappy image quality is due to false settings or the software is crappy itself (as it sounds like it). As there are also several compression cycles involved, image quality loss is a given, especially with lots of different software titles.

kev6677
Aug 1, 2010, 11:30 PM
ok very possible.... can you recommend good method for editing AVCHD (software or otherwise) I would prefer not to have to spend any more money than I have already spent on my imac

douglasomar
Aug 20, 2010, 12:04 PM
ok very possible.... can you recommend good method for editing AVCHD (software or otherwise) I would prefer not to have to spend any more money than I have already spent on my imac

Kev6677 i completely sympathize with you. Let's however ask the experts.
So gentlemen, how do we get the best quality into the hands of the consumer.
We have the hardware: AVCHD camera.. we cant to see the same quality on our HDTV's after editing. I have already used one arm and a leg to purchase the computer / Mac and the camera. Let's hope i don't have to use my other arm and leg to get this to work.
Using the most common software, please tell us how we can get the best quality
out to our HDTV's.
I'm personally using FCE, to edit the footage and should i be using FCP instead? Anyway one of you geniuses can provide a quick tutorial and proceed from there? Please :).