Shooting and Editing in AVCHD vs. MOV

[John Rofrano]

[Jerry Hart] “I have read that .MOV is superior.”

You have misinterpreted what you were reading. MOV is not a video format. It has no quality. MOV is a file format produced by QuickTime and native to the Mac. You can have a MOV file with AVC/H.264 video in. You can have a a MOV file with MPEG-2 video in it. You can have a MOV file with DV video or Motion-JPEG, etc. It’s just a file format. The quality comes from the CODEC that is used to encode the video inside the file and the BIT-RATE used to encode it. The LUMIX GH-3 shoots AVC/H.264 all of the time so you will get the same encoding regardless of the container (MOV or MP4 or MTS). The difference in quality for that camera will be in the bit-rate used.

Allow me to restate what you have read in a different way to make it true: “MOV quality on the LUMIX GH-3 is superior“. This has nothing to do with the fact that it is a MOV file and everyting to do with the fact the LUMIX GH-3 records at 3x the bit-rate when writing to a MOV file.

[Jerry Hart] “Am I sacrificing quality by originating in AVCHD with my LUMIX GH-3 and not .MOV?”

Yes, and here’s why: The LUMIX GH-3 shoots at a higher bit-rate when writing to MOV files than MTS files. That means you are sacrificing quality by shooting AVCHD @ 24Mbps instead of AVC/H.264 @ 73Mbps because you will have less bits to represent your image.

[Jerry Hart] “If I want to eventually get to AVID DNxHD what do I lose by shooting in AVCHD 24P at 24Mbps vs. .MOV 24p (All-Intra) at 72Mbps.”

Quality is determined by two factors: codec and bit-rate. Since your camera uses the same codec for MTS and MOV files there will be no quality difference from the codec. That leaves the bit-rate. All you have to do is look at the numbers: 72Mbps can represent 3x the information of 24Mbps. What do you think? (hint: shooting at 72Mbps will give you higher quality than shoot at 24Mbps)

[Jerry Hart] “I want a theatrical quality resolution.”

If you are really hung up on quality then you should be shooting in MOV format with that particular camera because of it’s higher bit-rate. The most likely reason that it is not playing back smoothly in Vegas Pro is because 72Mbps takes 3x the bandwidth to playback than 24Mbps does! So it’s probably not the file format (MOV vs MTS) but rather the size of the video recorded (i.e., bit-rate) that is causing your computer to choke. Does you laptop use a 5400RPM hard drive? If so, you might want to swap it for a 7200RPM hard drive or an even faster SSD drive. Even then your CPU might not be able to process at that high a bit-rate unless it’s a Core i7 Quad.

Your delema now is do you buy a new computer that can handle the high bit-rate of your camera or do you sacrifice quality and shoot at a lower bit-ate with your camera to accommodate your under-powered computer? That decision can only be made by you.

~jr

http://www.johnrofrano.com
http://www.vasst.com

[Jerry Hart]

John: Thanks for the great information. I think I will begin shooting .MOV 24p (All-Intra) at 72Mb/s and limp along with my system. I can edit OK… it’s just that playback is a bit jumpy. I think my system should be able to handle it even though it’s not a super rig. Here are the specs:

ASUS Laptop X52F-XF1
Processor: Intel i3-370M, 2.4GHz
Graphics: Intel GMA X4500HD
Ram: 8 gig Ram
C: Primary Drive 500g 7200rpm
D: Back up Drive- 2TB Western Digital
F: (For Projects only)CalDigit V2 2TB Raid connected to USB2.0 (two Hitachi 7200rpm)

Even though USB 2.0 to the RAID could be a bottleneck, it’s still rated at 480Mb/s, so that shouldn’t be the problem. I guess Core i3 is the problem. I’m sure it’s a long way from a Core i7 Quad.

I’ve been to your site and have considered building an Intel Hex Core Video Editing Workstation that you recommend, but can’t afford it right now. So I’m starting filming my new project next week on .MOV 24p and hope to get through for the time being.

One further question. Is my question regarding image quality on a cinema screen raising a moot point? Aren’t both formats (codecs and bit-rates) a compromise of some sort. Maybe the difference at the final stage of screening is not noticeable at all (or very little, if any). What do you think?

[Phil Seymour]

Just a thought… why not edit with proxy files and then let the computer do the heavy stuff (render) overnight. The i3 is a bit underpowered to cope with high bit rates. As John said an i7 quad core is really needed.

Windows 7 Pro64, i7 CPU, 16GB RAM, SSD boot drive, GTX 570 Graphics, Vegas Pro 12

[Nigel O’neill]

[John Rofrano] “The LUMIX GH-3 shoots at a higher bit-rate when writing to MOV files than MTS files. That means you are sacrificing quality by shooting AVCHD @ 24Mbps instead of AVC/H.264 @ 73Mbps because you will have less bits to represent your image.”

I had no idea that there were cameras out there that shot at such a high bit rate. I thought 36 Mbps was the bees knees 🙂

What reasonably priced video cameras out there can you suggest/recommend that shoot at such high bit rates?

[John Rofrano]

[Jerry Hart] “Processor: Intel i3-370M, 2.4GHz “

Wow Jerry that is NOT good. The Core i3 is definitely not designed for working with video. Look at Intel’s web site and see what they say:

Intel Core i3 Processor: Smart performance starts here for common tasks like listening to music

Intel Core i5 Processor: Smart performance with a speed boost for video, email, and Internet

Intel Core i7 Processor: Ultimate smart performance for multimedia creation and serious multitasking

The Core i3 is a minimalist CPU designed for web surfing and word processing and not much else. The Core i5 is for multi-media consumption and the Core i7 is for multi-media creation. So your CPU is woefully underpowered for content creation and is at the heart of your problems (i.e, it’s the equivalent of the Celeron in the Pentium line if you remember those.)

[Jerry Hart] “Even though USB 2.0 to the RAID could be a bottleneck, it’s still rated at 480Mb/s, so that shouldn’t be the problem”

You have just identified your second problem. That number is not the sustained data transfer rate and USB is a dumb interface that requires your CPU to do the data transfer. So now your underpowered CPU has to transfer the data and try and decode it. You should use Firewire or eSATA which are a smart interfaces that will free your CPU from having to do the data transfer.

[Jerry Hart] “I’ve been to your site and have considered building an Intel Hex Core Video Editing Workstation that you recommend, but can’t afford it right now. So I’m starting filming my new project next week on .MOV 24p and hope to get through for the time being.”

If you want to shoot some footage and send a small sample to me via Dropbox or something, I’d be happy to place it on the Vegas Pro 12.0 timeline and see how the HexCore handles it.

[Jerry Hart] “Is my question regarding image quality on a cinema screen raising a moot point? Aren’t both formats (codecs and bit-rates) a compromise of some sort. Maybe the difference at the final stage of screening is not noticeable at all (or very little, if any). What do you think?”

No, 72Mbps AVC/H.264 is extremely high quality. People are delivering 50Mbps MPEG-2 to the big screen. You should be fine.

~jr

http://www.johnrofrano.com
http://www.vasst.com

[John Rofrano]

[Nigel O'Neill] “What reasonably priced video cameras out there can you suggest/recommend that shoot at such high bit rates?”

Why do you need that high a bit rate?

I have to admit that I don’t keep up on the latest cameras but I’m a firm believer that if you can’t see an increase in quality then it doesn’t matter. In other words if my eyes can’t see the difference between 24Mbps and 72Mbps why would I shoot at the higher bit rate? Now the answer might be because I’m going to process the footage heavily and 72Mbps will hold up better than 24Mbps but if I can’t see the difference in the end, I’m going to shoot with the minimum needed to get the job done. My work is not viewed in a cinema so I don’t stress over this.

Don’t forget, I’m still shooting HDV with my Sony Z1U and no one is complaining about picture quality. Yea I’d like to have a Sony EX3 and shoot 35Mbps MPEG-2 or shoot XDCAM at 50Mbps but my work doesn’t demand it.

At the end of the day, the picture quality is determined more by the glass in front of the camera than the bits being recorded behind it so don’t get too hung up on bit-rates.

~jr

http://www.johnrofrano.com
http://www.vasst.com

[Jerry Hart]

Thanks again for all the terrific information.

My system is really running better than you think. I found in the control panel that I actually have an i5 M450 2.4Ghz (not i3 which I read on the sales receipt) But I know it’s still the source of the problems I have of occasional jittery playback.

I tested 24p .mov 72Mb/s footage rendered to Blu-ray Main Concept MPEG-2 (.m2v) 1920×1080 24p at 25 Mb/s and the Blu-ray looked smooth and beautiful. So, thanks for the offer to view footage but I don’t think it’s needed. Thanks to the forum I now have a good idea of how to proceed and a good understanding of the problem.

I’m starting filming my first project with this new camera LUMIX GH3 and even though the film may never see theatrical distribution, I still want to have the best possible quality in case it does.

As I said, I’ll limp along in post with this laptop for the time being. I’ll probably be building an Intel Hex Core Video Editing Workstation that John Rofrano/Video Guys recommends sooner than I planned. I guess I’m looking at $ 2k – 2.5k.

The LUMIX GH3 is the best performing cinema DSLR for the price ($1,300.00) Check it out:

https://www.bhphotovideo.com/c/product/892456-REG/Panasonic_Lumix_DMC_GH3_Mirrorless_Digital.html

Thanks again. This Forum is really, really helpful.

[John Rofrano]

It sounds like you’ve got it sorted out. Don’t forget Phil Seymour’s suggestion of using proxies. Vegas Pro 12.0 has proxy support built right in now so that’s a great alternative workflow if the MOV files are playing back too slow.

~jr

http://www.johnrofrano.com
http://www.vasst.com

[Hans Douma]

Hi John,

Very interesting and clarifying. It makes me wonder WHY all these different formats (envelopes) if codec and bitrate determine what is really going on. The only reasons I can think of are legacy and “my format is more important”. In any case, I find it extremely confusing to have all these formats like MTS, AVI, MOV and what have you while basically they are all just containers.

So, just to check if I get this right: I have an MTS file of 4GB, codec H.264/MP4 AVC and bitrate 9kbps. When I import this into iMovie it creates a MOV of 30GB with codec Apple Intermediate Codec and an average bitrate of 8Mbps. Would the massive increase in file size with a factor 8 be caused mainly by the bitrate difference ? And why this apparently very inefficient conversion in the first place ?

[John Rofrano]

[Hans Douma] “Very interesting and clarifying. It makes me wonder WHY all these different formats (envelopes) if codec and bitrate determine what is really going on. The only reasons I can think of are legacy and “my format is more important”. In any case, I find it extremely confusing to have all these formats like MTS, AVI, MOV and what have you while basically they are all just containers.”

Hans, I couldn’t agree with you more. In the old days there were “standards” like DV that meant something. Every camera could read and write the same DV tape. Today, HD is a mess of compromises. Even in a single HD format like HDV, cameras from different manufacturer’s cannot read each others tapes. With tapeless it gets even worse. Camera manufacturers just make up their own file formats with no regard to compatibility. It’s sad that no one can agree on standards anymore. This is absolutely a case of “my format is better than your format” and the consumer looses every time.

[Hans Douma] “So, just to check if I get this right: I have an MTS file of 4GB, codec H.264/MP4 AVC and bitrate 9kbps. When I import this into iMovie it creates a MOV of 30GB with codec Apple Intermediate Codec and an average bitrate of 8Mbps. Would the massive increase in file size with a factor 8 be caused mainly by the bitrate difference ?”

Not entirely. It’s primarily caused by the codec. The AVC codec use very high interframe compression and Apple Intermediary uses very low intraframe compression.

[Hans Douma] “And why this apparently very inefficient conversion in the first place ?”

To keep the playback rate high and the data loss low. Intraframe codecs contain complete frames. All you need to do to decode a frame is process that one frame. This can be done very quickly with very little CPU. Interframe codecs only contain a complete frame once in a Group Of Pictures (GOP). If the GOP is 15 frames, then there is one complete frame and a combination of 14 delta and predictive frames. This yields very high compression and achieves very small file sizes but it requires you to process 15 frames just to display 1 to it is very CPU intensive to decode and there is a lot of data loss. So Apple Intermediary achieves high quality and good playback rates at the expense of larger files.

~jr

http://www.johnrofrano.com
http://www.vasst.com