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I just bought a 2016 Full HD (not 4K capable) video camera and it supports encoding in AVCHD (I believe this is AVCHD 2.0) and MP4. The available Full HD formats are:

AVCHD

  • 1080:60p 1920x1080 60p 28mbps
  • MXP 1920x1080 60i 24mbps
  • FXP 1920x1080 60i 17mbps

MP4

  • 1920x1080 60p 35mbps
  • 1920x1080 30p 24mbps
  • 1920x1080 30p 17mbps

I read multiple sources of information online saying that AVCHD was of higher quality and that it should be the preferable option. However my concern is that, unless I choose the high bitrate AVCHD 108060p option, AVCHD is an interlaced format. Here are my questions:

  • Isn't interlaced a thing of the past that should be avoided nowadays because interlaced screens are just don't available anymore ?
  • When editing my video, I will plan for the final product to be encoded in a 1080:30p mp4 file. Will the deinterlacing process reduce the quality when compared to shooting in 30p right from the camera ?
  • Like mentioned earlier it is often mentioned that AVCHD is of better quality, in my camera I have 24mbps and 17mbps options for both formats, will AVCHD look better even if the bitrate is the exact same (and as far as I'm concerned the codec used is also the same H.264 but I guess encoding parameters may differ) ?
  • Finally, when AVCHD 2.0 was defined, 1080 at 60p was included in the standard, why wasn't 1080 at 30p also included since most if not all video equipment is now using progressive displays.

Sorry for the long question but I think this is all related and I never found a good source of information online that was answering these questions.

Thanks.

  • If you post mediainfo readouts for a clip recorded as AVCHD 60p and one for MP4 60p, we can give more informed answers, but off the top of my head, the video coding layer of both formats is the same. In which case, the MP4 60p, due to having the highest bitrate, is your best option. – Gyan Nov 5 '16 at 4:39
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AVCHD as a format is a combination of containers, file naming conventions, and directory structure. It is not inherently better or worse than any other container types.

Interlaced video is a thing of the past, forget about it.

If your final product is 30p, you can shoot at 30p, edit at 30p and render at 30p. Or you can shoot at 60p and edit at 30p - this allows you to use 60p for 0.5x slo-mo. If you don't want slo-mo, then just drop 60p into 30p timeline, and any decent editor will simply throw away every other frame.

Yes, deinterlacing reduces quality unless you shoot PsF or 24P with pulldown. Even then, if you do not properly remove the pulldown, your video will be ruined. Even if you remove the pulldown, your chroma still may remain interlaced. Long story short, prefer native progressive formats for any and all frame rates. If you really need to deliver interlaced, converting from progressive to interlaced is much easier than deinterlacing.

Clearly, your camera shoots with better quality in MP4 mode simply because it provides higher bitrate, which is always better provided all other settings are equal.

I believe that 1080p30 is included in AVCHD standard. Many camcorders shoot in this format.

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I will answer only to the 'interlaced' part. Yes, it's a thing from the past. Deinterlaced video always will be looking worse than progressive. It's like shooting through the cracked lens and then trying to fix the footage on post. In any circumstances don't shoot a scene with chromakey in interlaced mode. I won't go into details but the results will be terrible. Advantages of 60p: you will always be able to make slow motion; due to less motion blur, it'll be easier to key the footage.

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I'll take on the whole answer. If your target delivery format is interlaced, because it says so in the specifications, then shoot interlaced. But if you are not shooting for commercial, and not bound to interlaced specifications, then progressive is where it's at.

The fundamental choice of interlaced vs. progressive (based really on your intended delivery format) has a far greater effect on your perceived video quality than AVCHD vs. MP4 for similar bit rates. Yes, there are multi-thousand dollar converters that will do a half-decent job interpolating between the interlaced and non-interlaced worlds, but they, too, will introduce greater artifact problems that if you shot according to your intended delivery format.

If you cannot get the video quality you want from a 35Mb/sec 1080p60 or a 24Mb/sec 1080p30 video file, the solution is to get a camera that does meet your quality specs, chances are high that you will also not get it from a 28Mb/sec 1080i video format from that camera.

  • "All playback devices... are progressive" is overstating things greatly. There are many, many older interlaced only displays out there. Consumers don't replace things the second something new comes out. Also, the majority of transmission systems, except OTT, are still interlaced. Depending on what your target audience/distribution is, it can make more sense to stick to interlaced. – Michael Liebman Nov 6 '16 at 18:09
  • Can we agree that somebody who is creating content on a consumer digital device with decidedly non-Class 1 specifications is not so worried about broadcast distribution, thus mooting the transmission system leg of your argument. – Michael Tiemann Nov 6 '16 at 19:14
  • Network? Probably. But in the US, local cable and even broadcast advertising production is done with some pretty questionable quality equipment so I'm reluctant to make generalizations without knowing what the target usage is. – Michael Liebman Nov 6 '16 at 20:29
  • "If your target delivery format is interlaced, because it says so in the specifications, then shoot interlaced." - even if your target format is interlaced, still shoot in progressive if you can get the same image rate, like 60p for 30i delivery or 50p for 25i delivery. In particular, EBU has been advocating using 1080p50 for initial acquisition and mastering for the last 20 years, even if delivering in interlaced format. Now the Europeans are reaping benefits of this fateful decision, as Europe is switching to 1080p50 broadcast. – Rusty Core Jan 11 at 5:17

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