Pete's guide to home video IV - Capturing your video
Capturing your video
You have your footage on tape in the camera. You need to get it onto your computer's hard disk so that you can begin editing. Here's how. By the time you're done capturing, your footage will be on your hard disk, probably in the form of a set of AVI files.
Formats - DV, MPEG
I'm assuming that your camera uses DV format (Digital8 or MiniDV tapes). If you have a camera that records in MPEG-2 format, such as one that records to an internal hard disk or on Mini-DVDs, the process may be different and this article may not be of much use. (Mini-DVD disks should drop straight into your computer's DVD drive - far more convenient than messing with cables and connectors.)
You need a huge disk
As I mentioned in the first post in this series, DV format provides only slight compression of the video data. As a result the camera records a LOT of data - about a gigabyte for every four minutes of footage - and the AVI files that will hold this data on your hard disk will be about the same size.
For this reason it's probably a good idea to have a large second disk for holding your video files, rather than putting it all on your system disk (the C: drive on a Windows system). There are other technical reasons for keeping the video files off the system disk if possible, such as that the computer will be accessing system files on that drive at the same time as you're editing and that will slow you down some.
I have a second internal disk, about 60GB, which is about full of video files. I also have an external 250Gb USB drive. My older footage is no longer on disk, but I keep all the original tapes so if I ever need to recover the stuff I can read it back in.
Disks are getting bigger all the time - 500Gb disks are available and affordable, and recently Toshiba (I think) announced a 1Tb (that's a Terabyte, or 1000 Gigabytes) disk that will soon be available for around $400US.
If you're planning on doing a lot of filming, I suggest getting the biggest disks you can afford.
USB vs. Firewire
If your camera has a Firewire interface I'd advise using that (you may need to buy a Firewire card for your computer). There are two reasons for this:
First, Firewire is a little bit faster than USB 2.0 (and a lot faster than USB 1.0). USB 2 actually streams data at 480 Megabits per second compared to 400Mb/sec for Firewire so appears at first sight to be faster, but USB has higher transmission overheads and the bottom line is that Firewire is actually the faster of the two in practice. There is also an 800Mb/sec version of Firewire, but I don't know if there are any cameras that use this (if there aren't yet, you can be sure there will be before long).
However, the main reason for using Firewire is that USB is notorious for getting the audio and video out of sync by the time the data gets to your hard disk. This is a widespread problem that seems to affect many cameras when using USB, and it's not always consistent - sometimes everything's in sync, sometimes it's off by four or five frames, maybe more.
If you have a camera that has only a USB interface this is something you should be aware of - and that you're stuck with, I'm afraid. You may be able to fix the problem during editing, if your editing program allows you to detach and "slide" the audio and video tracks with respect to each other. You could buy a clapperboard, just like professional film makers use - it makes it easier to sync the video and audio by lining up the "snap" sound with the video frame that matches. (And now you know what a clapperboard is for. I also read about one guy who, whenever he finishes a shot, steps in front of the camera and claps his hands a couple of times - about as effective, obviously cheaper, and a handy trick to remember.)
Very dependent on the software
Most camcorders include a capture program as part of the package. Unfortunately the performance and features of these programs usually leaves a lot to be desired. As an example, the software that came with my Sony camera limits you to 10 minutes of capture at a time and doesn't know how to break the data down into individual files for each shot. This means a lot of work in breaking the files down by hand before editing can begin in earnest - a time-consuming and irritating procedure.
The Vegas software I bought fixes that; it includes a far better capture program whose only downside is that it only works with Firewire. It senses the places where I started and stopped the camera and automatically uses those markers to break the data stream into individual files, one for each shot. It doesn't limit the length of a shot, so if I leave the camera running for 30 straight minutes (as I did once) it'll capture the lot into one 30-minute file without complaining. By the time I'm done capturing to disk, every shot is in its own file, numbered in sequence, ready for editing. Having once been through the manual process of cutting and trimming, which took me several evenings to complete, I can't recommend highly enough finding a capture program that does this step for you.
Additional sounds
Sometimes you might have a project that involves having additional sounds available. I have a pocket digital recorder that I can use for collecting such things as voiceover dialogue, odd sounds for use as effects, stuff like that. It connects with USB and I can save the sounds to my hard disk as WAV or MP3 files.
You can also buy royalty-free music and collections of sound effects for use in your movies.
The reason I mention these here is that gathering extra sound files can be considered part of the capture process, since you can't complete editing your movie until you have them and in my experience it's a good idea to have all your sound and video files in place ready before you start.
In the next (and last) article...
Editing your movie.
You have your footage on tape in the camera. You need to get it onto your computer's hard disk so that you can begin editing. Here's how. By the time you're done capturing, your footage will be on your hard disk, probably in the form of a set of AVI files.
Formats - DV, MPEG
I'm assuming that your camera uses DV format (Digital8 or MiniDV tapes). If you have a camera that records in MPEG-2 format, such as one that records to an internal hard disk or on Mini-DVDs, the process may be different and this article may not be of much use. (Mini-DVD disks should drop straight into your computer's DVD drive - far more convenient than messing with cables and connectors.)
You need a huge disk
As I mentioned in the first post in this series, DV format provides only slight compression of the video data. As a result the camera records a LOT of data - about a gigabyte for every four minutes of footage - and the AVI files that will hold this data on your hard disk will be about the same size.
For this reason it's probably a good idea to have a large second disk for holding your video files, rather than putting it all on your system disk (the C: drive on a Windows system). There are other technical reasons for keeping the video files off the system disk if possible, such as that the computer will be accessing system files on that drive at the same time as you're editing and that will slow you down some.
I have a second internal disk, about 60GB, which is about full of video files. I also have an external 250Gb USB drive. My older footage is no longer on disk, but I keep all the original tapes so if I ever need to recover the stuff I can read it back in.
Disks are getting bigger all the time - 500Gb disks are available and affordable, and recently Toshiba (I think) announced a 1Tb (that's a Terabyte, or 1000 Gigabytes) disk that will soon be available for around $400US.
If you're planning on doing a lot of filming, I suggest getting the biggest disks you can afford.
USB vs. Firewire
If your camera has a Firewire interface I'd advise using that (you may need to buy a Firewire card for your computer). There are two reasons for this:
First, Firewire is a little bit faster than USB 2.0 (and a lot faster than USB 1.0). USB 2 actually streams data at 480 Megabits per second compared to 400Mb/sec for Firewire so appears at first sight to be faster, but USB has higher transmission overheads and the bottom line is that Firewire is actually the faster of the two in practice. There is also an 800Mb/sec version of Firewire, but I don't know if there are any cameras that use this (if there aren't yet, you can be sure there will be before long).
However, the main reason for using Firewire is that USB is notorious for getting the audio and video out of sync by the time the data gets to your hard disk. This is a widespread problem that seems to affect many cameras when using USB, and it's not always consistent - sometimes everything's in sync, sometimes it's off by four or five frames, maybe more.
If you have a camera that has only a USB interface this is something you should be aware of - and that you're stuck with, I'm afraid. You may be able to fix the problem during editing, if your editing program allows you to detach and "slide" the audio and video tracks with respect to each other. You could buy a clapperboard, just like professional film makers use - it makes it easier to sync the video and audio by lining up the "snap" sound with the video frame that matches. (And now you know what a clapperboard is for. I also read about one guy who, whenever he finishes a shot, steps in front of the camera and claps his hands a couple of times - about as effective, obviously cheaper, and a handy trick to remember.)
Very dependent on the software
Most camcorders include a capture program as part of the package. Unfortunately the performance and features of these programs usually leaves a lot to be desired. As an example, the software that came with my Sony camera limits you to 10 minutes of capture at a time and doesn't know how to break the data down into individual files for each shot. This means a lot of work in breaking the files down by hand before editing can begin in earnest - a time-consuming and irritating procedure.
The Vegas software I bought fixes that; it includes a far better capture program whose only downside is that it only works with Firewire. It senses the places where I started and stopped the camera and automatically uses those markers to break the data stream into individual files, one for each shot. It doesn't limit the length of a shot, so if I leave the camera running for 30 straight minutes (as I did once) it'll capture the lot into one 30-minute file without complaining. By the time I'm done capturing to disk, every shot is in its own file, numbered in sequence, ready for editing. Having once been through the manual process of cutting and trimming, which took me several evenings to complete, I can't recommend highly enough finding a capture program that does this step for you.
Additional sounds
Sometimes you might have a project that involves having additional sounds available. I have a pocket digital recorder that I can use for collecting such things as voiceover dialogue, odd sounds for use as effects, stuff like that. It connects with USB and I can save the sounds to my hard disk as WAV or MP3 files.
You can also buy royalty-free music and collections of sound effects for use in your movies.
The reason I mention these here is that gathering extra sound files can be considered part of the capture process, since you can't complete editing your movie until you have them and in my experience it's a good idea to have all your sound and video files in place ready before you start.
In the next (and last) article...
Editing your movie.
Labels: Video
posted by Pete Ford at
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