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Posted by PTravel on 02/14/07 23:00
"Frank" <frank@nojunkmail.humanvalues.net> wrote in message
news:rt37t2t7rfda7h4pfiqfrk0np4vqt57pd7@4ax.com...
> On Wed, 14 Feb 2007 12:01:14 -0800, in 'rec.video.desktop',
> in article <Re: MPEG4 Camcorders - any good?>,
> "PTravel" <ptravel@travelersvideo.com> wrote:
>
>>A couple of points:
>>
>>1. Some HD TVs do a good job up-converting 640i (standard definition
>>video), and some do an absolutely atrocious job, while looking good with
>>HD
>>material.
>>
>>2. All transcodes (the process of converting non-mpeg2 source material to
>>mpeg2) are not created equal. DVD camcorders, entry-level editing
>>packages
>>and dedicated software transcoders all produce DVD-compliant mpeg2.
>>However, the differences in resulting video quality will be dramatic. DVD
>>camcorders do single-pass, on-the-fly transcodes and result in the worst
>>quality. Entry-level editing packages (and even some mid-range to
>>prosumer
>>packages) usually compromise on transcode quality and optimize for short
>>transcode time. These will produce better DVDs than a DVD camcorder, but
>>they're stll not the best. The highest video quality will be achieved by
>>using a stand-alone transcoder program that can do 2-pass, 10-bit, maximum
>>motion search transcodes. There are inexpensive solutions for this -- I
>>use
>>tmpgenc -- but transcode time with this product is measured in tens of
>>hours
>>(transcoding a 2-hour video can take up to 24 hours on my 3 GHz P4). More
>>expensive (much more expensive) software transcoders can achieve equal
>>quality in somewhat less time, though I'm not aware of any that can do a
>>quality real-time transcode, i.e. 2 hours to transcode a 2 hour video.
>>The
>>differences in video quality between a DVD camcorder, an entry-level
>>all-in-one package and a properly-produced stand-alone transcode are
>>obvious
>>on a good standard definition television. On an HD TV that has good
>>upscaling capability, the differences will be very dramatic.
>>
>>3. I'm strictly a hobbyist. I produce video for myself, my wife and my
>>in-laws, along with the occassional Youtube upload (and I do have my own
>>non-commercial website on travel video just for fun). As you note,
>>everyone
>>has their own standard for what is "good enough." I don't know your
>>standard, but I can tell you this: I wouldn't expect anything remotely
>>acceptable from the Sanyo. The focus of its design is a gimmick, i.e. a
>>small form factor and tapeless video. I see many, many posts in these ngs
>>from people asking, "why does my video look so bad?" The answer will vary
>>depending on how the video was produced, but often the answer is: "you
>>used
>>a lousy camera with crappy glass that produces video at high-compression
>>rates and with low data bandwidth." No amount of post-processing can
>>"fix"
>>video like that. As they say in the computer field, "garbage in, garbage
>>out." Because my videos are important to me, I strive for the best
>>quality
>>I can (within reason). The DVDs that I can produce come pretty close to
>>commercial quality, but I use a prosumer camcorder, edit with prosumer
>>software (Premiere Pro), transcode for highest quality and author the DVD
>>with a high-end consumer/prosumer package (Encore). That may be more
>>trouble than it's worth for you, but my feeling is that the memories I
>>preserve this way will be something I want to see for the rest of my life.
>>
>>With all that said, if you're still interested in the Sanyo, I'd suggest
>>trying it hands on in a store that will output the video to a decent
>>monitor
>>(don't rely on the camera's lcd or viewfinder). Try it under a variety of
>>lighting conditions, particularly low-light. Do some quick pans to see
>>how
>>it handles motion artifacts. If you're satisfied with what you see,
>>you'll
>>probably be satisfied with a DVD produced from the video. Bear in mind
>>that, regardless of how impeccable your technique, the video quality on
>>the
>>DVD will be degraded from what you see. The 1080i television issue is a
>>red
>>herring. A good up-converting 1080i television will hand a DVD as well or
>>better than a standard def television. A poor-upconverting 1080i set will
>>not. Finally, remember that commercial DVDs of films are not good sources
>>to judge the 1080i upscaling ability for home video. Because of the
>>difference in film and video frame rates, televisions (both SD and HD)
>>have
>>to do 3/2 pull-down -- showing some frames longer than other frames. This
>>is complicated by having to handle interlace issues (that's what the "i"
>>in
>>1080i stands for). Because most people want to watch DVD movies on their
>>HD
>>set, a lot of attention is paid to the 3/2 pull-down system, with less
>>paid
>>to displaying 640i (standard definition) video material.
>
>
> In the above post, please change all occurrences of "640i" to "480i"
> (576i in PAL-land).
>
> Thank you!
You are, of course, absolutely right. I don't know what I was thinking when
I wrote that. Thanks for correcting it. :)
>
> --
> Frank, Independent Consultant, New York, NY
> [Please remove 'nojunkmail.' from address to reply via e-mail.]
> Read Frank's thoughts on HDV at http://www.humanvalues.net/hdv/
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