AVCHD Curiosity

[Calstvns]

I am unfamiliar with the AVCHD format, and learned of it during our recent discussions about "writing HDV back to a cam" ... Ken and others mentioned the format as an alternative to showing HD on my HDTV.

I looked for a tutorial about it so I can learn about the format. There's one tutorial written by a guy about his process, how he gets his AVCHD content uploaded. It did not seem to give a kind of overview for someone who knows nothing about the format.

How can I learn about this? I take HD video with my Sony HC3, currently upload it to the computer and try (with some difficulty--see my other latest thread--) to put my finished product back onto a tape, then use my cam as a vcr and show it on my HD TV. But I wonder if I could produce AVCHD disks instead and use a player that will accommodate them.

If anyone has a place to point me for some lessons, or if you have a workflow you can share, please help if you can. Thanks so much.

[Ken Berry]

I don't know of any tutorials though you might find something by a Google search. But if you don't mind some of my wandering thoughts you might want to take a look at http://phpbb.ulead.com.tw/EN/viewtopic. ... 891#160891 and also http://phpbb.ulead.com.tw/EN/viewtopic. ... 143#161143

[Calstvns]

Thanks, Ken

I've noted on a couple of occasions that you use a PS3 player to show your AVCHD discs. Is the choice to use a PS3 a cost-based choice? Or is there a technical reason why the PS3 player is preferred to a regular blue-ray player?

The reason I ask is this: Since I'm having troubles getting HD content to record back onto my cam, I am thinking seriously about the AVCHD option and playing my projects that way. So if I buy a blue-ray player, will it play the AVCHD discs? If so, that might be a cost-saver versus the high cost of BD media... pay for a player, but save on those pricey discs by creating AVCHD. Does that work?

Also, I read in your earlier posts (that you gave me in your last post here) that when you create AVCHD you upscale the VBR from the default. I gather that both the default and the up-scaled VBR are both less than regular HD (which is 25000). Why is the VBR in AVCHD not as high as the HD content? Does this mean that the AVCHD end-product is only somewhere in-between SD and HD, but still not as good as HD?

thanks!

[Ken Berry]

Unfortunately, one way or another, you will need to spend money to be able to watch your HDV or AVCHD on your HDTV. The only way which does NOT involve expenditure is the simple one of exporting it back to your HDV camera -- which is what started us on this track in the first place!

The other options -- the ones that cost! -- involve lashing out (considerably!) and buying both a Blu-Ray burner and player, plus the very expensive blank Blu-Ray discs, and actually burning your project as a Blu-Ray disc.

But there is the half-way house you have asked about: a hybrid AVCHD disc. But the catch is that you require a player than can play such discs. Again, that involves Blu-Ray and Blu-Ray players are still rather expensive, and in addition, *not all of them are rated to play such hybrid discs*.

But the Sony PlayStation 3 is one such player (not the X-Box, I am afraid). And the PlayStation 3 (PS3) adds a number of options. First, it will play hybrid discs. But the catch with them is that if (like me) you want the best quality playback from your high def original video, then you have to, understandably, use the highest quality settings for AVCHD. And that means that you can only squeeze about 20 minutes of high def video onto a single layer standard DVD. That's OK for me since I pay only about 25 cents per DVD blank (when the cheapest Blu-Ray blanks here are literally 100 times that price -- each!) VS11.5+ and X2 (and the recently released Movie Factory 7) also allow you to build a proper menu for such discs, unlike a number of other editing packages at the moment.

But the PS3 is even more versatile. I have mine networked to my computer, and the PS3 also connected via HDMI to my 46" HDTV. Using Windows Media Player or Nero Media Home as the server, I can thus play all my edited video (in any format, not just HDV; plus still images and music) direct to the HDTV via the PS3. Top quality and wonderful!!

But wait! There's more!! (Sony should be paying me!) You can also transfer your edited HDV to either a suitably large USB stick or even an external hard drive, and plug either of those into the PS3 and play your edited HDV back on the HDTV that way. The only catch is that the PS3 can only see drives formatted with the 'old' FAT32 system, not the current NTFS one. This in turn means the maximum size of the individual files it can play is 4 GB (a FAT32 limitation). For HDV format, this is again around 20 minutes of video, which luckily, 95% of my projects are -- I don't like to bore people (too much... Embarassed )

And finally, you can burn an edited HDV clip slightly larger than 4 GB to a standard DVD (i.e. max. 4.3 GB) but as an archive/storage disc, not a video disc. And when you put that in the PS3, as long as it is in a folder labelled VIDEO (in upper case!), the PS3 can see it and play it in all its high def glory as well...

All of my personal options above, of course, mean that you have to invite friends and family to your home to see your masterpieces in high def. But until such time as the price of Blu-Ray burners, players and discs come down considerably, and all your family and friends have at least a Blu-Ray player, your options are in any case limited to either standard DVDs (still) or one of my options...

Anyway, here endeth the lesson!

As for your question about bitrates, well the answer is relatively simple: AVCHD is mpeg-4 and uses a different technology to process it. It also has a frame size of 1920 x 1080. Both these factors mean that at high quality settings, AVCHD is just as good as HDV, and some would say better. Canon, by the way, has recently released an AVCHD camera which can film with a bitrate of 24 Mbps, which is now the new upper limit for AVCHD. The problem is that software manufacturers have yet to catch up with that development.

HDV, by the way, as you probably know is mpeg-2. It may have a higher bitrate, but its frame size is a smaller 1440 x 1080 maximum.

[sjj1805]

All I want for Christmas is a PS3!!
Thanks Ken, that is a very illuminating and comprehensive explanation.