CAPTURE
GUIDES -> Capturing AVI
The following
guides are for capturing AVI with any capture card.
(1) Capture AVI with VirtualDub
(freeware)
(2) Capture AVI with iuVCR
(free trial, about $25 to buy)
NOTE: This guide should work with both style of cards,
either the older VFW (Video For Windows) cards or newer WDM
(Windows Drive Model) cards. When using Windows XP,
VirtualDub should support both VFW and WDM cards, while
iuCVR only supports WDM cards. Most video hardware developed after
2000 uses WDM drivers. Detecting whether you have a WDM card is normally pretty easy. Aside from when the card was made, the letters “WDM” will often be in the driver name, seen in the Windows device manager.
This guide was tested with an AVerMedia BT8x8 chipset video
capture card, and an ATI All In Wonder Rage Theatre chipset
video capture card.
Using
VirtualDub to capture AVI
This guide was tested with VirtualDub v1.5.1 using an ATI All In Wonder card
(WDM).
NOTE: Not all cards will work with VirtualDub. Many cards based on the BT8x8 chipset, a very popular and cheap WDM-based card, will not cooperate with a VFW-to-WDM bridge or VFW software. Not all new video cards come with backwards
compatibility. Simply try it to see if it works.
Open VirtualDub and go to File -> Capture AVI. It will launch the VirtualDub capturing interface.
Capture settings. The main window of the capturing
console shows preview in the main window, and information on
the right-hand side. At the bottom of the screen are the
audio and video settings. VirtualDub comes with very low
quality default settings, so most settings need tweaking.
Change from 15.00 fps to 29.97 fps (full NTSC). The audio
setting is also too low, but it will be changed somewhere
else.

Audio settings. Go to the Audio menu, and go down to Compression. A new will open with the audio settings. Change it to PCM format using 48.000 kHz 16-bit stereo. Click Save As and give the new settings a name. I choose “DVD 48k” for mine. Click OK. You should now notice the audio level is 48K/16/s in the lower-right corner of the capture console.
Go back to the Audio menu. This time go down to Volume Meter. The Balance should be in the middle, meaning both the left and right stereo get the same amount. The Volume control bar should be at about 50 to 75 percent. Never put volume at 100 percent, as it will often lead to distorted, cracking audio. The left side of the slider bar is 0 percent, the right side is 100 percent. Click the X when done.
One last time, go the Audio menu. Go to Windows Mixer. It will launch the Windows volume controls (you can also get here by double-clicking on the speaker icon in the system tray). Select the soundcard input. For most people this will be either LINE IN for an external soundcard input or AUX for an internal connection.
Standard video settings. VirtualDub has an extensive list of video capture options. This hack will help you with the basic settings and give some brief information on the more advanced optional settings. Go to Video and set it for Overlay mode if it is not already set. Overlay is the area of the graphics cards that plays live video data.

Go to Video, and then Format. Set this resolution to an appropriate number, preferably 640x480 or 720x480. Set the compression mode to YUY2 if available. Click OK to return to the capture console.
Next go to Video, and then Source. This is where you select the video capture card to work with VirtualDub. On the Capture Source tab, select the video card and the input (coax tv tuner, s-video, or composite). If using a TV tuner, click on the TV Tuner button to change the channel and select the signal format. In the USA, the signal is NTSC_M. On the Device Settings tab, alter as needed to make color corrections to the video. Realize the PC and TV may not look the same, so never alter color, contrast, brightness, etc., without running test captures and playing the results on a TV set first.
Now go to Video, and then Compression. This is where you select the AVI codec used at capture. For high quality captures meant for DVD, it is suggested to stay with uncompressed or low compression codecs like HuffYUV or MJPEG (Morgan, PicVideo and MainConcept all make MJPEG codecs). However, for computer-only viewing, formats like DivX and Xvid may be used. Codecs must be installed separately, they do not come with the computer. Some are free, some cost money (typically $30 or so). Codecs come and go, and new ones surface all the time, so visit
www.videohelp.com/tools
to find the most updates and newest codecs. If capturing for DVD, be sure the codec supports interlace (MJPEG and HuffYUV do). Click on the Configure button to tweak the codec settings, normally just to verify interlace fields being captured and raise the quality to higher levels. Click OK and go back to the capture console. Go to Video, and then Compression Compatibility. Match this settings to the one you made in the Compression settings.
Optional Video Settings. Anything below Compression Compatibility on the Video menu is optional. These are advanced features for improving video quality.
Go to Video, and then Cropping. First, enable it
(OPTIONAL). Then go to Set Bounds. This will allow you to only capture a certain portion of the video. Just be aware that you cut off pixels doing this. If you trim off 5 pixels from each side on a 640x480 capture, the final file will be 630x470 in size. This is a filter for advanced work only.
Go to Video, and then Noise Reduction to enable noise
reduction (OPTIONAL). This setting can remove noise on the video capture, but it will increase system CPU usage, and may result in dropped frames depending on the compression.
Go to Video, and then Filters (OPTIONAL). This will launch the filters console. VirtualDub filters use a plug-in method, so many filters exist, made by many people. VirtualDub comes with 25 or more filters, and more can be added. Search google.com or sites like
videohelp.com for more filters, as well as detailed explanations on what they do.

READY TO CAPTURE!
Go to File, and then Set Capture File. Type in the name and select the location for your capture file. AVI files can be rather large, so be sure the hard drive selected has plenty of space, at least 10 GB or more, preferably 20-30GB minimum for full-length movies.
Finally, go to Capture, and Capture Video. F6 on the keyboard is a shortcut for this command. Press Capture again (or F6 again) to stop the capturing.
While the video is capturing, pay attention to the information in the info box of capture console. Dropped frames are not good. If you are dropping frames, see the
dropped frames guide.
______________________________________________________________________________
Using
iuVCR to capture AVI
For testing this guide, settings
of 720x480 29.97fps video and 48Khz audio were used with the
HuffYUV 2.11 codec or the MainConcept MJPEG codec. Capturing
at Half-D1 352x480 produced a noticeably softer and less
detailed image with this card/software combo, as is typical
of BT8x8 chipsets.
Why use iuVCR? Because VirtualDub (the most popular
AVI capturing utility) is an older VFW-based capture program
that does not always want to cooperate with many
newer-generation WDM-based capture cards, even with the VFW-WDM
bridge installed.
Start capture and open new file. Open iuVCR, select
the File tab. In the Name field, enter a name for your
capture. To browse your system for a location to capture to,
use the folder icon to the right of the Name field. See
image:

Video settings. Next, go to the Video tab. Under
Device Settings, you can select the capture device. The only
one in the test system is an AverMedia card, so it is
automatically selected. Under Compression, you can select
your preferred codec from a drop-down list of installed
codecs. I tend to use either HuffYUV 2.11 or the MainConcept
MJPEG codec at quality setting 19 or 20. See image:

Audio settings. Under the Audio tab, you can select your
audio recording device, set your input level and sample
rates. The mixer input, in conjunction with your Windows
audio mixer, should be adjusted to give you a solid signal
without distortion. This will take some playing around. I
suggest spending some time capturing some short clips,
checking the sound and changing the balance, until you find
a good setting.
Options settings. Under the Options tab, you can set
your preview options. I've selected the Smart Tee preview
because it gives me a resizable frame where I can preview
the video input. Under the AVI MUX settings, the only one to
adjust is the Master Stream which is set to Audio. Under
Synchronization, I have selected Short Audio Samples. This
seems to be the key to getting very tight audio sync.
Using HuffYUV, I drop between 6 and 8 frames per hour. Using
MJPEG, I drop no more than 1-2 frames in 90 minutes. Even
with dropped frames in HuffYUV, the audio stays tight. If it
does go out for a second, it usually corrects itself instead
of drifting worse as time goes by. See image:

Presets options. Once you have a setting that works well
for you, you can make a preset out of it. Go to the Presets
tab and click on Add. It will bring up a box where you can
name the preset. When you want to use those same settings
again, you can go to the Presets tab, select from the list,
and click Load. WARNING:
Whatever file name you are using when you set the preset
will be loaded every time you load that preset, so make sure
you double-check your file names before starting the capture
- otherwise you may overwrite your previous work!
Info options. The Info tab will give you an overview of
your settings, your system usage, your average data rates
and your frame rates... basically everything. Once you hit
the Start Record button, iuVCR will switch to this tab so
you can monitor the capture. The Start Record button will
become Stop Record, and the Snapshot button will become a
Pause button. See image:

FINISHED! Once you've captured your video, hit Stop
Record. Close out of iuVCR. Being paranoid, I tend to
immediately open the file I've just captured and spot-check
it for sync issues. If there are none (as usual), it's time
to encode.
Page Last Updated: May 13th 2005
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