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  1. I'm interested in getting a DV Camcorder but I'm not sure I understand how this Firewire stuff works.

    Let's say, I've recorded 30 mins on my new DV Camcorder and it's connected to the firewire card.

    Do I simply transfer the 30 mins of DV from the camcorder to the PC ??

    Or

    Do I need to re-encode the 30 min camcorder footage with software like Media Studio 4 ??

    I've always taught it would be like copying a file from the floppy or CD to your hard drive. But I can't find any information that clear says that it is just a transfer or encoding ???

    Please advise .......

    Bye,

    s@d
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  2. It works like this:

    1) you recorded, let's say, 30 mins of video using a digital camcorder
    2) connect the camcorder to the PC via Firewire (you need a Firewire card and software for this). Put the camcorder in VTR mode (like a VCR to play video)
    3) run the video capture software to capture the video, the software automatically commands the camcorder to play

    Some software allows you to specify how long to capture, some will automatically stop capturing when it hit the truly blank area (i.e. never recorded on) of the tape. If you are using Win98 or ME, it will stop capturing every 18min or so. Windows 2000 does not have this phenomena.

    The DV camcorder already compressed the video (I believed 5:1 compression ratio) before it sends video data to the PC.

    So, capturing from DV camcorder is essentially copy the content of the tape into the PC. The unfortunate part is that copy operation is done at the video play speed instead of 4X or 8X (due to the camcorder, not the PC).




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  3. OK ... You use the word "capture" to mean transfering the DV from the camcorder to the PC ...... is this right ???

    So, the software does not do any encoding as would happen if I captured with the ATI AIW Radeon from a VCR.

    What's confusing or misleading is the process of "capturing" the DV ... why not just copy the DV just as you would stills from a FLASH Card ...
    Bye,

    s@d
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  4. Yes or No.

    Yes, the DV info is not re-compressed during firewire "capturing".

    No, It's still not a direct file trandfer. While capturing, the software will add some thing into it like file head etc. and put it in forms of AVI file structure.

    Some professional video devices do have the ability to transfer raw DV info directly, in that case, the file extension name is .dv, not .avi
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  5. Do you lose any quality in the resulting AVI file ???

    What about dropped frames ???

    Will I have to worry about dropped frames ????

    _________________
    Regards,

    Romande

    <font size=-1>[ This Message was edited by: romande on 2001-07-03 04:02:10 ]</font>
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  6. DV camcorder "capture" is a digital transfer with no quailty loss and no re-encoding.

    Yes, you may have to worry about dropped frames, if your computer cannot keep up with the heavy amount of data coming from the camera. A DV format AVI file uses about 235 megabytes per minute. Potential problems are: 1) your hard drive cannot write the data fast enough 2) system interruptions (either CPU stuff like other programs; or PCI bus traffic from poor designed sound cards, network cards, etc.)

    Unless you are using Windows NT or Windows 2000 with an NTFS formatted disk partition, you will have to use a capture program that breaks up the incoming data into smaller files. FAT32 formatted disk partitions used by Windows 98 cannot create files bigger than 4GB (18 minutes).
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  7. The quality of the captured material also depends on the decoder which you use when to reencode the DV to either MPEG1 or MPEG2 (or whatever).
    I'm interresting in finding the best decoder and the best settings for TMPEGENC to make the resulting MPEG2 compliant to DVD.
    I reencode to 720x576 and demux with BBDMUX and then I author DVD with DVDMaestro. Quality is very good at average 5000 and peaks at 9800. But there is always room for improvements.
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  8. Member
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    A limitation is also the software itself (ie. capturing bandwith speed, avi conversion) which will not give a 100% reproduction of the DV tape itself (in terms of quality). However, using max bitrate settings in TMPG, you can get about a 97% reproduction.

    If you truly want a 100% reproduction, then you should get a real-time MPG2 hardware encoder.
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  9. romande,

    regarding your statement:

    "the software does not do any encoding as would happen if I
    captured with the ATI AIW Radeon from a VCR. "

    This is not true, when you capture from the a VCR using analog capture card like ATI, then there will be hardware (if the card supports it) and/or (mostly) software compression while you are capturing.

    DV is different, the camcorder already compress 5 to 1 and it sends compressed data to the PC. The capture software will not compress this DV data stream.

    Even a hardware MPEG-2 capture will not yield 100% reproduction because MPEG-2 is a lossy compression. Captured at very high bit rate, the lost part may be unnoticeable to human eyes.


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