Difference between AVCHD and DVCPROHD?

it's hard to compare them as there hasn't been a consumer DVCPROHD camera or a professional AVCHD camera
when the HMC150 is out it'll be easier to compare the 2
on paper DVCPROHD is a lot better, but then it takes up more HDD room. they are made for 2 different worlds. if you want to make a movie with heaps of chroma key work and colour correction then the HVX would be far superior to the HCM, however the HCM would be great for event coverage or documentary work.
I find that in many circumstances superior and inferior formats perform similarly, it's only when the task at hand pushes a format to it's limits that another format may have suited the task better.
 
basically one is a codec based in h264 compression, Long GOP, 4:2:0 color space, but capable of full 1920x1080 encoding. The other is based on- EDITED FOLLOWING JAN'S RESPONSE POST BELLOW- a "sorta"mjpeg compression, professional grade, intraframe, 4:2:2, which is fantastic for post production, but its limited to 1440x1080 on PAL and 1280x1080 for NTSC in max resolution.

translates to:

AVCHD:

More recent codec, more efficient compression, AVCHD format is a consumer long GOP format, which means teoretically good for capture, but inferior for editing (needs heavy computer HP). 4:2:0 colorspace is similar do HDV. As Barry Green said, AVCHD (in high bitrates) is like a "super HDV". Capable of 1920x1080 recording. 8 bit codec. Relative small files. Needs super computer for native editing. Used on consumer cameras (untill the HMC150 is released.)

DVCPRO HD

Professional Broadcast codec. Heavy compression and limited capture resolution to 1280 or 1440 vertical lines. 4:2:2 colorspace. 8bit codec. Large files 1GB for 1 minute aprox. (in 1080 mode). Can be edited on a Powerbook g4 1.67ghz in realtime. Codec used in cameras whose price range goes from 6k to 50k, and, prior to the introduction of AVC-INTRA, the professional codec of choice used in all Panasonic broadcast line. Used to cover major sport events troughout the world (dvcpro HD 720p60). Proven professionaly.
 
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SPZ said:
basically one is a codec based in h264 compression, Long GOP, 4:2:0 color space, but capable of full 1920x1080 encoding. The other is based on mpeg1 compression, intraframe, 4:2:2, which is fantastic for post production, but its limited to 1440x1080 on PAL and 1280x1080 for NTSC in max resolution.
Click to expand...

First, DVCPRO HD is not MPEG or anything like it. It is more like an MJPEG, but not really. It does start with a DCT and goes from there, but on a frame by frame basis. When you talk about the recorded full raster pixel map, you need to recognize that if there is any lacking in the signal or in the algorithm, it will show. You really need a codec that will support the full raster or just expect that sooner or later you will find that the compression engine will come back to haunt you.

That is if you were to look at the HDCAM, DVCPRO HD, XDCAM HD algorithms you would see that the size of the record is not a direct match up to the HD format either in 720P or 1080i/p. This is not because of the recording is being limited to a less than pixel for pixel rendition of HD, it is due to the pre-filtering done in the codec for optimizing the compression. There are high frequencies that can be rolled off and not be missed and if you don't you end up with more data to compress. When you play it back out of the uncompressed output you have the full raster for display purposes.

For example, if you have a 1920 X1080 signal and you compress it to 25 Mbs, that is a lot of compression. HD starts at an uncompressed bandwidth 994Mbs in 8 bit. So there is a lot of compression required to get it to 25Mbs. However, you prefilter some of that off, the compression ratio falls. So take DVCPRO HD, without prefilter the compression ratio is 10:1 roughly, however with the prefilter it is 6.7:1. The second is vastly more desireable.

The problem that people have here is that the numbers mean something but they do not mean what people might think. At a full 1920 X 1080 image in contrast to a 1440 X 1080 image there is approximatyely 40% more signal to compress. More is not always better unless the algorithm can handle it.

That said, AVCHD for all intents and purposes is like the new HDV but more efficient. It is an interframe codec and thus no frame stands independently resolution-wise, just like all of the other long GOP formts, HDV, XDCAM HD, XDCAM EX.

DVCPRO HD is an intra-frame codec, so that all of the compression that is going to happen is going to happen within each frame and it doesn't need to consider the next frame or the previous frame.

Hope this helps, or at least adds to the discussion,

Jan
 
Sounds to me like the bottom line is that AVCHD might help to provide more luminence detail from the increased resolution but at a trade off of having less color space with inferior color sampling and not being intra-frame.

For me, personally, I think I prefer DVCPro HD because of the great color reproduction and the ease of editing on relatively standard computer gear. I like the workflow of DVCPro HD / P2 on my trusty old Dell PC and laptop :)

... I cannot say this wholeheartedly, however, as I have never worked with AVCHD.
 
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Jan_Crittenden said:
First, DVCPRO HD is not MPEG or anything like it. It is more like an MJPEG, but not really. It does start with a DCT and goes from there, but on a frame by frame basis. When you talk about the recorded full raster pixel map, you need to recognize that if there is any lacking in the signal or in the algorithm, it will show. You really need a codec that will support the full raster or just expect that sooner or later you will find that the compression engine will come back to haunt you.

Jan
Click to expand...

I stand corrected. You can't find better info than from the source itself!
 
I found this thread during a search and thought I would revive it with my question.

What is the best way to convert CANON avchd to dvcprohd? Panasonic has a utility which does this but ONLY for Sony, not Canon.

I woud rather not go through ProRes just to get to dvcprohd, unless it is recommended for some reason. If so, should I use compressor or?

thanks in advance,
td
 
tduncan said:
I found this thread during a search and thought I would revive it with my question.

What is the best way to convert CANON avchd to dvcprohd? Panasonic has a utility which does this but ONLY for Sony, not Canon.

I woud rather not go through ProRes just to get to dvcprohd, unless it is recommended for some reason. If so, should I use compressor or?

thanks in advance,
td
Click to expand...


When working with canon files, I use Cineform to make the files 1280x720.
They are so easy to edit, and even if the file started out as 1080, the difference is not good enough for me to keep the files at 1080.

I like cineforem at 1280x720 24p.
The canon files convert well to that format.
 
The longGOP is what bothers me...all those virtual frames.. I do alot of wilderness/hunting shooting. How well does AVCHD stand up to small, random organic movements, aka a slight movement in the trees or the movement of water? I assume the codec has a hard time because there is simply too much motion, so you get artifacts. Does the codec sacrifice resolution in this case?
 
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