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How to put digital video on CDs
Objective
The objective of this page is to show how to put video coming from a digial videocam onto CDs with a good compromise of file size and quality.
Input: Analog vs. Digital videocams
It is actually much easier and cheaper to transfer video from the newer digital videocams as it was from the older, analog ones.
Why ? Well, the key problem with video is that it is a lot of data. To transfer analog video into a computer you need capture hardware, the simple ones simply convert the analog signal to digital images. A lot of images. If you try to capture those images with today's computers and harddrives, you will lose most of the frames, because your hardware will be too slow.
Even if you reduce frame size and rate, you will need some software compression method (probably MJPEG), to reduce size for your harddrive.
A more expensive solution is for the capture hardware to have hardware compression. While this works well, quality is not as good as it could be, since the compression has to be done in real-time.
So back to video from a digital videocam, the trick is, the videocam already has a high-quality compression chip, this is how it can work at all. So all you have to do is transfer the already compressed data from the videocam into your computer. This can be done with a Firewire card. How will be explained in the following paragraphs.
Video Standards
A word about video standards. Most of the world uses PAL, the US, Canada and Japan use NTSC. For the purposes of this page the difference looks like this: PAL NTSC
Resolution 720 x 576 720 x 480
Frame Rate 25 frames per second 29.97 frames per second
So as you can see, PAL has a slightly bigger picture and NTSC stores more frames per second, average numbers in the following paragraphs are for PAL and will probably differ somewhat for NTSC.
From a videotape to a CD
The steps to getting the video from your digital videocam to a CD are:
Transfering the video from your videocam to your computer via Firewire, resulting in a full quality video file on your harddrive
Converting the video to a smaller format
Burning the CD
Sounds simple, but of course there are problems on the way, this is why this page is here ^_^
Necessary Hardware
Memory
You will need at least 128MB of RAM, or you will lose frames.
Harddrives
To store an 80-minute tape you will need about 18 Gigabyte of harddrive space (probably different for NTSC). An EIDE-system should be configured like this:
First drive on primary IDE-controller (Master): Windows and the swap file
Second drive on secondary IDE-controller (Master): Unfragmented partition of at least 18GB of free space
Activate the DMA-mode for your harddrives
If your system is configured differently you will lose frames.
I don't have a SCSI-system, but the same rules should apply there.
Firewire Card
Firewire cards are not much different, so unless you have really bad luck you shouldn't have a problem getting a good one. Be sure it comes with a cable and good video editing software. I bought the EX-6500 from Exsys and am happy with it. It came with Ulead's Video Studio and cost about $100 and it has even gotten cheaper by now.
Necessary Software
Windows
Anything less than Windows 98 Second Edition will cause problems, also be sure to run Windows Update to get the latest Firewire drivers. The instructions on this page are for Windows 98SE, if you use a newer version, names might be different.
Video Editing Software
Your Video Editing Software needs the following things as a minimum:
Read DV-format
Write MPEG1
Load multiple video-files to edit an output-file
The program I use is Video Studio from Ulead.
AVI_IO
I said an 80-minute tape will take up about 18 Gigabyte of harddrive space. Well, there is a problem with that. Under Windows the maximim size of any file is 4GB. So you will need a software, which will capture your video and split the files at the right time without losing any frames.
There is only one software known to me that does this job perfectly, its name is AVI_IO and you can get a demo version at www.nct.ch/multimedia/avi_io/, the full version costs $25.
DV Codec
There are two ways to work with video under Windows "Video for Windows" and "DirectShow/ActiveMovie", the latter one being newer, but not necessarily better. With Windows you get Mediaplayer2 which gives you DV Codecs for DirectShow, but to be able to work with all the software mentioned on this page, you will also need a DV Codec for the other method. Download it from Mainconcept and install it.
Installing the Firewire card, videocam and software
If at all possible, do things in this order:
Open your computer and plug the Fireware card in an unused PCI slot. If possible choose one which doesn't share Interrupts (see your Mainboard manual).
When you boot up, Windows will ask for a driver, choose "Texas Instruments OHCI-kompatibler IEEE 1394 Host Controller" (this is the German name, the English one will be similar).
Then attach your cable to the Firewire card and your videocam, turn it on (as if you would hit Play next), and Windows will ask for the DV-Cam driver. Choose "Microsoft DV-Kamera und Videorecorder" (again, this is the German name, the English one will be similar to "Microsoft DV-Cam and VCR"). Do not choose the Texas Instruments-Driver, it will cause problems later !
Next you can install your video editing software and AVI_IO.
Capturing video
If you've come this far, you have solved all the problems, it's just a matter of doing and patience now.
So attach your cable to the Firewire card and your videocam, turn it on, hit Play and Pause, so that you can see the first picture of the video you want to capture.
Start AVI_IO, if necessary choose the correct capturing device.
Next, use the default "Capture settings" except for:
Frames per second: Enter the correct frame rate for your video system (25 or 29.97)
Insert/Modify Disc: Enter a filename on your free hard drive
Next go to "Video Settings" and turn the Preview off, otherwise you can run into problems later.
Now hit "Start Capture", hit Play on your videocam, and you are capturing ! When you want to end, hit ESC.
Converting video
Now that you have the raw video data on your harddrive, you can start your video editing software, load the video files you want, attach them any way you like, insert special effects, etc. Once the project looks like you want it to be, you can save the video file, converting it to MPEG1.
To get a good compromise between file size, picture size and quality choose the following MPEG1-settings: PAL NTSC
Resolution 352 x 288 352 x 240
Frame Rate 25 frames per second 29.97 frames per second
Video Rate 1500 Kbps 1500 Kbps
Audio Rate 256 Kbps 256 Kbps
Audio Settings Layer 2, 44.1 KHz, Stereo Layer 2, 44.1 KHz, Stereo
"Saving" your project means encoding it into MPEG1. Depending on how powerful your system is, this can take quite a while. After this process you can burn the resulting file(s) on your CDs.
That's it !!!
2006-06-22 02:18:51
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answer #1
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answered by landkm 4
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