60 fps interlaced versus 29.97 progressive for MP4 movies (from Canon Vixia HF R300) - AVS Forum
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post #1 of 21 Old 06-23-2013, 12:07 PM - Thread Starter
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Hi folks,

I recently got a Canon Vixia HF R300 which allows for recording at 60 fps interlaced, 30 fps progessive, or 24 fps progressive.

I understand the concept of interlaced and progressive, and have even read up on e.g. deinterlacing.

But what's better to record in (what's higher quality): 60i or 30p? Or if they're practically the same, what other reason might I choose one?

The camcorder actually uses MTS files, but ultimately, I want to save most of the videos as "family memories" (which will be a lot more meaningful 30 years from now), so I'm just storing them on disk and need a format that will hopefully last the test of time. I'm using MP4 via Premiere Elements 11, but suggestions are welcomed. I think it will want to output MP4 at 29.97 fps.

Maybe I have already answered my question - should I record in 30p if my output will be 29.97 fps?

Thanks if you can help!

Mike
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post #2 of 21 Old 06-24-2013, 08:35 AM
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Originally Posted by MikeTheRed View Post

Hi folks,

I recently got a Canon Vixia HF R300 which allows for recording at 60 fps interlaced, 30 fps progessive, or 24 fps progressive.

I understand the concept of interlaced and progressive, and have even read up on e.g. deinterlacing.

But what's better to record in (what's higher quality): 60i or 30p? Or if they're practically the same, what other reason might I choose one?

The camcorder actually uses MTS files, but ultimately, I want to save most of the videos as "family memories" (which will be a lot more meaningful 30 years from now), so I'm just storing them on disk and need a format that will hopefully last the test of time. I'm using MP4 via Premiere Elements 11, but suggestions are welcomed. I think it will want to output MP4 at 29.97 fps.

Maybe I have already answered my question - should I record in 30p if my output will be 29.97 fps?

Thanks if you can help!

Mike
If you understand the concept you should be able to decide which is better - for you.
"30" usually means 30 * 1000 / 1000, which comes to about 29.97.
60i is 29.97 fps, interlaced. Also known as 30i and 29.97i.
60p is 59.94 fps, progressive.
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post #3 of 21 Old 06-24-2013, 09:07 AM
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Record in your highest quality you can , 60i AVCHD . Through my cable service company and my 37" LG LCD HDTV i am able to connect and watch my videos i have uploaded to Youtube on my HDTV . Between my videos takens with the HF M50 and other professional videos with high $$$ cameras i could not really tell quality difference except with the most high $$$ camcorders costing thousands . I watched several from other Panasonic and Sony cams that say they take 60p and i find them to be no different in quality than my HF M50 . What makes the DIFFERENCE is the person who edits them and how pro they are in editing and making video movies . That is the BIG difference . I've heard and read so many here tell this camera or that camera is best and they shoot 60p not like Canons that shoot 60i . On a small monitor you might see some difference cause of the monitor resolution but when you see it on a bigger screen where Canons 60i can expand properly is going to really make a difference in your mind what you think .
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post #4 of 21 Old 06-24-2013, 09:24 AM
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Originally Posted by ronlhodges View Post

Record in your highest quality you can , 60i AVCHD . Through my cable service company and my 37" LG LCD HDTV i am able to connect and watch my videos i have uploaded to Youtube on my HDTV . Between my videos takens with the HF M50 and other professional videos with high $$$ cameras i could not really tell quality difference except with the most high $$$ camcorders costing thousands .
Do you mind linking to one of your videos?
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post #5 of 21 Old 06-24-2013, 09:39 AM - Thread Starter
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Hi folks! Hmm, well... it's my understanding that:
  • Native format for PCs and other digital stuff is Progressive. Digital monitors can't actually do interlaced, though they will do the best they can (to show Interlaced on Progressive hardware). For example, if they are fast enough to do 60 fps, then they can actually just "fake" 60i. (Re-draw progressively at 60 fps with the new interlaced interleave.)
  • Methods for converting Interlaced to Progessive are messy and can a minefield (see article on deinterlacing).

Therefore, my tentative conclusion is to just go with Progressive to keep things simple. After all, you can argue that Interlacing is only an artifact left over from analog TV. If I'm keeping videos for the distant family future, may as well keep everything as digital as possible.

Ron,

I don't understand why you say 60i is the highest quality. Part of my confusion is that 60i is, in a sense, half the resolution of 30p - but twice as fast... so the purpose of this thread is to ask what might be better, the one or the other, since they are kinda sorta the same thing. Why do you think it's higher quality? You stated that in an absolute way, but then went on to give sort of subjective impression. Can you say more? I would appreciate it... I'm wondering if I'm missing something simple and straightforward.

Thanks all!

Mike

P.S. Ungermann, I will post one up ASAP. Will a couple of little (minute-long) clips of 30p vs 60i be ok?

Edit: Clarify question to Ron
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post #6 of 21 Old 06-24-2013, 10:11 AM
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Originally Posted by MikeTheRed View Post

I don't understand why you say 60i is the highest quality. Part of my confusion is that 60i is, in a sense, half the resolution of 30p - but twice as fast...
Interlaced has twice lower spatial resolution but twice higher temporal resolution than 30p. If your primary delivery platform is YouTube and you don't want slo-mo shots then go with 30p, it is easier to work with (BTW, your NLE will still say that it is interlaced because it is not native 30p, it is PF30, that is, 30PsF - "progressive segmented frame", google it). You need to pan more carefully than with interlaced to avoid stutter. You need to instruct your NLE to treat it like true progressive. You still may see ugly artifacts like shown below, because with PsF luminance is progressive, but chrominance is interlaced:

http://en.wikipedia.org/wiki/Progressive_segmented_frame
http://provideocoalition.com/awilt/story/review_canon_vixia_hf11_avchd_camcorder/

HF11-hummer.jpg

Or you can shoot everything in interlaced then convert to each field into a complete frame, this will produce 60p, but obviously you will have halved vertical resolution.
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Ungermann, I will post one up ASAP. Will a couple of little (minute-long) clips of 30p vs 60i be ok? Edit: Clarify question to Ron
Yep, this was addressed to Ron.
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post #7 of 21 Old 06-24-2013, 12:25 PM
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Originally Posted by Ungermann View Post

Do you mind linking to one of your videos?

You can choose any on this page at youtube . I watched them from my setup on my HDTV sunday and found them no difference in any of the lower cost consumer camcorders (meaning $1000.00 or cheaper) . Watching it from your computer you wont see what i saw but if you have a setup through your cable service and can watch it on your HDTV with at least a 37" you can see what i saw . You'll have to search tho for the other brands cause i have no way to bookmark those i saw that were other than mine . Not trying to cause controversy just stating that i could see no difference in camcorders of similiar products stated here on the forum . As far as the 24-30 or 60i settings canon suggest for the highest quality videos to be recorded in 60i AVCHD . With my M50 you have a choice of 24p , 30p or 60i . I've tried alll three and i agree 60i AVCHD is the best so i don't even mess with the 24p or 30p settings anymore . What i think IMHO to myself only that there is so much controversy to which is the best consumer camcorders that alot of people get confused . Most people here that ask are just after a good camcorder for their buck and could care less about all the bells and whistles and not into depth of the technology like some here are . If your making videos for comercial type work then yes it's good to know but other than that normal camcorders in same price ranges and quality are just about compareable with each other buck for buck . But like i did state what most are going to reconise is the editing of how the movie is put together and how it's made and sound or music that is added . If that part could be seperated form just ordinary videos it would be easy for people to make up their mind what they want by cost they can afford .

http://www.youtube.com/user/celestron8g8
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post #8 of 21 Old 06-24-2013, 02:49 PM - Thread Starter
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Hi folks! Thanks for helping!

Ungermann, that's very helpful, about the progressive segmented frame and, yes, my camera even says "PF30", even if the manual doesn't say a darn thing about PsF, per se.

Another wrinkle: I just noticed that the manual for the Canon camcorder (p. 94 of 226) says Frame Rate options are:
  • 60i (Standard): 60 fields per second, interlaced. Standard frame rate of NTSC analog TV signals.
  • PF30: Shooting at 30 frames per second, progressive.* Use this frame rate to easily edit your recordings, for example, to post them on the Web.
  • PF24: Shooting at 24 frames per second, progressive.* Using this frame rate will give your recordings a cinematic look.
* Recorded as 60i.
(Underlining is mine, to point out.)

Look at that asterisk... my camcorder is recording in Interlaced, even if I specify Progressive! This turns my previous argument around - if it's natively Interlaced, I probably should keep it that way.

Ron, I don't mean to be argumentative. When you said "60i is best quality", it sounded like a known fact, not a personal conclusion ... Every now and then I miss some obvious fact that everybody else seems to know. So I'm just asking if this is the case. tongue.gif
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post #9 of 21 Old 06-24-2013, 03:16 PM
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Quote:
Originally Posted by MikeTheRed View Post

Another wrinkle: I just noticed that the manual for the Canon camcorder (p. 94 of 226) says Frame Rate options are:
  • 60i (Standard): 60 fields per second, interlaced. Standard frame rate of NTSC analog TV signals.
  • PF30: Shooting at 30 frames per second, progressive.* Use this frame rate to easily edit your recordings, for example, to post them on the Web.
  • PF24: Shooting at 24 frames per second, progressive.* Using this frame rate will give your recordings a cinematic look.
* Recorded as 60i.
(Underlining is mine, to point out.)

Look at that asterisk... my camcorder is recording in Interlaced, even if I specify Progressive! This turns my previous argument around - if it's natively Interlaced, I probably should keep it that way.
Yes, it does shoot in progressive for PF30 and PF24, and it does record in interlaced. Nothing wrong about it. Google for "telecine". This is how movies have been and are broadcast, because broadcast channels are not set up for fast switching between scanning rates. How do you think 24fps movies are broadcast via an interlaced channel? Then your TV has to reconstruct 24p back from 60i stream, this is called "reverse telecine" or "pulldown removal'. This is what you must do if you want to shoot PF24 before editing it as 24p.

Editing PF30 is easy, you can edit it as 30p (you must instruct your NLE to treat each frame as a complete progressive frame) or you can edit it as interlaced if your NLE does not support editing in progressive (in this case each frame will be treated as two independent temporally-shifted fields.
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Every now and then I miss some obvious fact that everybody else seems to know. So I'm just asking if this is the case. tongue.gif
60i is not the best. 50p is the best smile.gif 60p is good too as long as you don't need 24p. Interlaced is good if you want fluid motion and don't have 60p. 30p is good for full spatial resolution if you deliver to YouTube anyway.
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post #10 of 21 Old 06-24-2013, 09:55 PM
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Originally Posted by Ungermann View Post


60i is not the best. 50p is the best smile.gif 60p is good too as long as you don't need 24p. Interlaced is good if you want fluid motion and don't have 60p. 30p is good for full spatial resolution if you deliver to YouTube anyway.

Canon HF M50 does not shoot 50p . It shoots 60i and outside the point when I said 60i I was talking about my HF M50 and that 60i was the best for my camera .
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post #11 of 21 Old 06-25-2013, 09:36 AM
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Originally Posted by ronlhodges View Post

Quote:
Originally Posted by Ungermann View Post


60i is not the best. 50p is the best smile.gif 60p is good too as long as you don't need 24p. Interlaced is good if you want fluid motion and don't have 60p. 30p is good for full spatial resolution if you deliver to YouTube anyway.
Canon HF M50 does not shoot 50p .
The European does. I was not talking about a particular camera, I was talking about the best format in general.
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post #12 of 21 Old 06-25-2013, 10:37 AM
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I am looking at this camcorder. It is advertised as 1080p 60P on mp4 format. Is that better than 60i AVCHD? I am confused.
Edit: sorry, I am looking at the Canon Hf R400
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post #13 of 21 Old 06-26-2013, 05:43 AM
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Originally Posted by agent8 View Post

I am looking at this camcorder. It is advertised as 1080p 60P on mp4 format. Is that better than 60i AVCHD? I am confused.
Edit: sorry, I am looking at the Canon Hf R400

Hi agent8 - For moving subjects, 60p looks better on the screen than 60i, period. The codec doesn't really matter. That said, the Canon HF R400 shoots MP4 and AVCHD, so you'll have your choice.

Now that Canon has started to incorporate 60p in their lower end camcorders, and kept the mic and headphone jacks, the HF R400 a very good value for money when compared to its Panasonic and Sony competition - especially when you can get one for $249 at Amazon (as of this post).

Hope this is helpful,

Bill
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post #14 of 21 Old 06-26-2013, 07:27 AM
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Thanks Bill. Costco actually has it for $219 and free shipping that comes with a 16 gig card and case so I think I am going to jump. The specs look like it will do 1080p 60p MP4 (35 Mbps) and AVCHD Progressive (28 Mbps). Is there any benefit to either one? I understand that mp4s can be thrown in a folder for later editing and avchd has to be imported but is the quality going to be the same?

I will be using Cyberlink Director or Sony Vegas along with Adobe after effects, My system is an i-5 processor, 8 gigs of ram, windows 7 64,570gtx video card that I build, if that helps. Thanks again!
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post #15 of 21 Old 06-26-2013, 10:29 AM
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AFAIK (and I may be wrong) MP4 files used by Canon and Panasonic are not "spannable" so to speak, that is, one MP4 file is a complete video. Hence they are great for short[er] clips, easier to move around. This does not mean that MP4 cannot be "spannable", XDCAM EX uses MP4 container and a video can span several files. But XDCAM EX also employs additional metadata just like AVCHD, so benefits of XDCAM EX over AVCHD are moot.

AVCHD video can span several files and in theory can be as long as the media allows, although Panasonic has hard limit of 12 hours, not sure why they did that.

Otherwise, if (and this is IF) all encoding parameters are the same, then 35 Mbit/s is always better than 28 Mbit/s. But the difference should not be huge. 50 Mbit/s with 4:2:2 color should be a whole different game. ;-)
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post #16 of 21 Old 06-26-2013, 03:25 PM - Thread Starter
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Hi folks,

Agent8, like they've said, 60p will be better than 60i. 60i is sort of half the resolution of 60p, as you can see in this thread. Of course, 60p files will be bigger than 60i, if all else is equal... but I'd take it. In fact, I'd rather just have 60p than have to choose between 30p and 60i (which is the subject of this thread). smile.gif But I don't have that option, with my R300.

The R400 at $219 sounds like a great deal to me... I got my R300 for $170 refurbished on eBay (Adorama Camera) a couple of months ago. That's a LOT of camera for the money, especially compared to nothing, but I gambled on refurbished, and it's about 2-year old technology. In contrast, I see that your manual was updated this month! I might mention a few things: The camera doesn't really have 53x zoom, just 32x (but that's still tons); my camera is not the best in low light conditions, which reviews also mentioned, and it looks like yours uses the same CMOS; and finally, the supplied BP709 battery only lasts a half hour so expect to shell out up to $110 just for each BP727 (three times as long)... the recording times relative to batteries quoted in the manual are for real. In theory there are much cheaper knock-off batteries out there, but I have been having serious trouble getting ones that meet claimed specs so far (while being real cheap). We can start another thread on their batteries if you want, if you get the camera.

Back to this thread, though (60i versus 30p)...

In theory, I would probably choose 30p instead of 60i. Most of my stuff is "family movies", which doesn't involve much action per se. Plus ultimately it's all intended to be played on the PC. (Just as PC movies, not as YouTube.)

But isn't there a stealth component to interlaced - namely, isn't it better than progressive if the camera is moving? (By moving, I mean rotating, which causes everything being photographed to move at high speed, essentially.)

Mike
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post #17 of 21 Old 06-26-2013, 04:47 PM
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Quote:
Originally Posted by MikeTheRed View Post

In theory, I would probably choose 30p instead of 60i. Most of my stuff is "family movies", which doesn't involve much action per se. Plus ultimately it's all intended to be played on the PC. (Just as PC movies, not as YouTube.)

But isn't there a stealth component to interlaced - namely, isn't it better than progressive if the camera is moving? (By moving, I mean rotating, which causes everything being photographed to move at high speed, essentially.)
Haven't we already covered that?

60p a.k.a. 59.94p - full spatial and temporal resolution
60i a.k.a. 30i a.k.a. 29.97i - half the spatial resolution of 60p, full temporal resolution
30p a.k.a. 29.97p - half the temporal resolution of 60p, full spatial resolution

Out of the three 60p is the best that is, it is the fullest in all criterias, and you can get 30p and 30i out of 60p. You cannot get 24p from it though.

Elsewhere, 50p is the best because you can get 25p and 25i from it, where 25p is pretty much the same as 24p motion-wise. And if you really-really want 24p just slow it down 4%.
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post #18 of 21 Old 06-26-2013, 05:11 PM - Thread Starter
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You have already said that, yes, Ungermann. I guess you're not seeing my point. No matter. Thanks for all your help.

If I can back up a little: Someone said that the R400 shoots "mp4 and AVCHD", as if the R300 doesn't. The R300 does, though. However, it has odd limits on MP4: you can't shoot more than 30 minutes or 4 GB, whichever comes first. Also, it can't be shot at Full HD. Apparently all this relates to YouTube (dumbing it down for YT users). But I have no interest in YouTube, so that's just a hassle. Ultimately it doesn't matter to me though because I can use Premiere Elements 11 to convert the Full HD MXP AVCHD to MP4, shrug. I see from its specs that the R400 handles MP4 better than the R300, though.
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post #19 of 21 Old 06-26-2013, 06:53 PM
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So with the r400 both do mp4 and avchd @ 60p. Any benifit of either one since they are both 60p and 1080p?
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So with the r400 both do mp4 and avchd @ 60p. Any benifit of either one since they are both 60p and 1080p?

There are pros and cons for both: MP4 is easier to edit in some software programs - AVCHD has unlimited recording time. If your editing program can handle it, I would record in AVCHD at 1080/60p.

Cheers,

Bill
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post #21 of 21 Old 06-26-2013, 10:32 PM
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Originally Posted by MikeTheRed View Post

You have already said that, yes, Ungermann. I guess you're not seeing my point. No matter. Thanks for all your help.

If I can back up a little: Someone said that the R400 shoots "mp4 and AVCHD", as if the R300 doesn't. The R300 does, though. However, it has odd limits on MP4: you can't shoot more than 30 minutes or 4 GB, whichever comes first. Also, it can't be shot at Full HD.
If you looked in the operating instructions you would see that MP4 on the R300 is 720p @ 9 Mbit/s max, 24p and 30p only. I don't know whether it is intraframe or interframe (google it), but for interframe this bitrate is barely enough, for intraframe it is too low.

4GB limit is not odd, it is related to FAT32 cluster size. I mentioned above that AVCHD allows multi-file take, while this particular MP4 implementation is single-file only per take.

So, if you want native 24p and your takes are shorter than 30 minutes and you don't mind the quality then MP4 is your easiest option, otherwise use AVCHD.
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