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Old Dec 27, 2011, 2:03 PM   #11
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Quote:
Originally Posted by markr041 View Post
"However I only just noticed that video as linked is only 720p/30fps
as opposed to what you said 1080p/30fps."

1. The share button on Youtube is for 720p. You go to the Youtube link and change the resolution to 1080p. Youtube converts the video. The bitrate Youtube uses is less than that used by the camcorder. And the quality is much less than the original.
Thank you, the video that you said was 1080p was the latest you had posted a link to on Vimeo (and not on YouTube) - as in your quote below:
Quote:
Originally Posted by markr041 View Post
Music - classical, rock, Chinese -, lights, toy trains, and Santa! All inside and underground.

http://vimeo.com/33095758

Yes, the W200 is very efficient because it makes good use of variable bit rate. For this 108030p video, the average bitrate is 17.9 Mbps, but it has a peak of 34.1 Mbps and a low of 7.1 Mbps.
That video on Vimeo only has options for HD or non-HD -
the HD version I downloaded was only 720p -
perhaps you can please tell me how to select 1080p version

Quote:
Originally Posted by markr041 View Post
I think what you are saying is confusing efficiency and quality, although perhaps I do not understand what you are saying.

2. You do not seem to understand what I am calling efficient. The vbr changes the bitrate a lot depending on the amount of information needed in the shot. Efficiency is measured by the variance (second moment), not the mean (first moment of the distribition of bitrates). The average bitrate tells us about the quality overall for an identical codec.

The W200 has an average bitrate that is much higher than the other cameras. That means it has higher quality (everything else the same). It is not "efficient" to have a lower average bitrate, *given all the cameras you are comparing use the same codec*; it's just lower quality. The codec deterimines the efficiency, and, again, that is the same on all the camcorders (AVC. h264). That the average bitrate is higher for mjpeg than for avc is becasue the avc codec is more efficient. But for the same codec, higher bitrate means higher potential quality.

I love this little program.
Thank you for your explanation.

I do agree with you that your Samsung video quality is VERY good I have said so previously and indeed your video-graphing was also very good in terms of composition camera movement and where you pause and resumed - those were very impressive videos.

However your Kodak Zi8 also uses vbr as shown in the Bitrate Viewer graphs I posted above -
again I agree that the Samsung W200 has better video quality -
but in good light, it is NOT 3x better to warrant almost 3x the bitrate or memory space-
that's the only point I was referring to in terms of efficiency -
the Kodak Zi8 manages to store a video that's say 80% quality of the W200 (that's probably unkind to the Zi8) in a space of 37% -
I would suggest that the Zi8 may be more efficient in its storage, even if one takes video quality into account?

Last edited by UnknownVT; Dec 27, 2011 at 2:12 PM.
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Old Dec 28, 2011, 7:58 AM   #12
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1. All the videos I uploaded are 1920x1080. That is the resolution in fact reported on the Vimeo site where my videos are downloadable (their report is based on their examination of the uploaded video, not on my say-so). You are making a mistake; they are not 720p. I have never made a 720p video (sorry about the confusion of Vimeo and Youtube - your incorrect statement about 720p threw me off). I have no idea why you get 720p, or think you do. I am talking about the original downloadable video; I do not know what the streaming video that Vimeo makes is.

2. If you meant by efficient that the Kodak Zi8 has 80% the quality and half the bitrate, ok. That is just simply telling us (interestingly) that (a) bitrate is not everything and/or (b) quality and bitrate have a nonlinear relationship. Not anything to do with any standard definition of efficient. Quality is what matters ultimately, as I am sure you agree.
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Old Dec 28, 2011, 11:53 AM   #13
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Quote:
Originally Posted by markr041 View Post
1. All the videos I uploaded are 1920x1080. That is the resolution in fact reported on the Vimeo site where my videos are downloadable (their report is based on their examination of the uploaded video, not on my say-so). You are making a mistake; they are not 720p. I have never made a 720p video (sorry about the confusion of Vimeo and Youtube - your incorrect statement about 720p threw me off). I have no idea why you get 720p, or think you do. I am talking about the original downloadable video; I do not know what the streaming video that Vimeo makes is.
Yes, I now see - you're right -
I was looking at the streamed video where there were only choices of HD or non-HD and using Video DownloadHelper (a FireFox add-on) I could download a 720p video - hence my reference to that.

I missed the download link lower down on the page -
my "lame" excuse is that I am so used to YouTube where they do not have any downloads - that I just use the Video DownloadHelper add-on to leech download a visible video - so I didn't even look for a download link.

My apologies for the confusion - my bad.

Quote:
Originally Posted by markr041 View Post
2. If you meant by efficient that the Kodak Zi8 has 80% the quality and half the bitrate, ok. That is just simply telling us (interestingly) that (a) bitrate is not everything and/or (b) quality and bitrate have a nonlinear relationship. Not anything to do with any standard definition of efficient. Quality is what matters ultimately, as I am sure you agree.
I agree that
(1) bitrate is not everything and
(2) it does not have a linear relationship to quality.

The Samsung W200 is better because
(a) most probably it has a better sensor (it's BSI CMOS technology - which has demonstrably better low light performance/quality)
and
(b) possibly the lens - Samsung has relationships with Schneider-Kreuznach and Pentax......

Bitrate matters, if using too much compression, it visibly degrades the image - unfortunately one can only judge this if "everything else is equal" - where this is patently not the case.

The Zi8 is a very good example in this case, where until the Samsung W200 - it was considered to have one of the "best" video quality for a pocket HD camcorder - yet its videos have pretty high compression -
it is a lot more compressed than its stablemate the Kodak Zx3
yet the visible quality seem on par with each other
- please see:
This interesting video comparison of the bit-rates of the Playsport Zx3 and the Zi8.

YouTube - 2010 07 29, Zi8 vs zx3

The poster claims the Zx3 uses constant bit-rate (cbr)
- whereas the Zi8 uses variable bit-rate (vbr)

Thanks for the conversation,
and your patience.
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Old Mar 3, 2012, 10:54 PM   #14
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thanks for those videos mark, i'm downloading them now and i know they'll be a great help. now that you've had the cam for awhile, how to you compare the samsung vs the zi8 overall in terms of quality?
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