What is a video codec ? How to install and use it ?

Dear friends,

Last month I bought a capture card but things are still too confusing for me;

I have 5 capture softwares installed :

1) Adobe Premiere 6
2) Virtual Dub
3) Ulead Video studio 6 (came bundled with ATI AiW card)
4) ATI TV (came bundled with ATI AiW card)
5) Nero Vision

In all of them, when capturing AVI files, at 720 X 480 resolution, Audio in CD quality mode, I’ve been having 1,17 GB files for each minute !!!!

Am I doing something wrong ?

Also, I've noticed the following :

Adobe, Virtual Dub and Nero vision : allows me to choose a video codec, but drop LOTS of frames !!

ATI TV and Ulead : I haven't found an option to choose a video codec, but good point is that they DON'T DROP frames at all ! Are they locked to use only their native video codecs ?

It's weird for me....


What is exactly a Video Codec ?

Do they reduce quality of captured video ?

May I use any to reduce the horrendously big size of AVI files (1 min = 1,17 GB !) ?

Isn't it weird that two softwares don't drop frames at all, while the other 3 sw's drop LOTS !!!??

Does anyone know how to install and choose a video codec to use with Ulead and ATI TV ?

I have adjusted all softwares to save capture files at the big dedicated 80 GB HD....

I have a fast system :

Windows XP with SP1a
ASUS A7N8X Deluxe MB – updated BIOS and chipset nidia
AMD ATLHON 2.4 XP
512 RAM DDR
20 GB HB (Master on primary IDE)
80 GB HD, dedicated only for capturing (Slave on Secondary IDE)
SONY DRU-500AX Recorder (Master on Secondary IDE)
LG CD RECORDER (Slave on Secondary IDE)
Creative Sound Blaster Live Platinum sound card – all updated drivers for XP
ATI All in Wonder 8500DV AGP video card – all updated drivers for XP
Direct x 9.0a
Windows Media Encoder 9

Please, point me the right way to make video capture

Thanks to all,

Andre

[aklendathu]

There may be no simple answer to your question.

First, about codecs. Do a google search for AVICODEC, download and install this program. It will tell you about all the codecs installed in your system and also about the codecs required to play any AVI file.

A video codec will compress the video stream so that the resulting video file will be smaller. If you capture at 720x480@29,97fps, 16-bit frames, well, do the math and you'll see that a very large uncompressed file will result unless the video is compressed.

There are two types of codecs: lossless (such as Huffyuv) where the video quality is preseved (but at the expense of a larger file) and lossy (such as PicVideo or Morgan MMJPEG) where the quality of the video is slightly degraded but a larger compression is achieved.

The compression process involves a lot of CPU work and also depends on the codec you choose. In my home system (Athlon XP 1800), using the PicVideo at quality 19 (20 is max) gives me a compression ratio of about 7 and an average CPU usage of 30%. However, the Morgan Codec will use almost 100% CPU except at modest settings.

You can use the Windows Task Manager to monitor CPU usage. If your codec is using up too much CPU then dropped frames will result. Try using more modest settings (e.g. less compression) or another codec.

Another source of dropped frames may come from disk access but since you can write uncompressed files without any problem other than the size I think you're OK in that respect.

I hope this helps you find a solution to your problem.

[Will Hay]

It's never easy to detect the reason for lost frames but I would always recommend a second hard drive, (quick) formatted before each capture and used only for capturing.
Capturing to your primary (only) HDD is never wise.
The following post might be of some use:
Why does my system drop frames
Will

[pbhalerao]

Andre

In all of them, when capturing AVI files, at 720 X 480 resolution, Audio in CD quality mode, I’ve been having 1,17 GB files for each minute !!!!

This is quite normal.

Will Hay and aklendathu are quite correct on dropped frames. If these techniques don't work and you stiill get dropped frames, then I suggest that you stick to ULead ot ATI for capturing (if you are satisfied with the quality, that is).

While capturing, capture at the maximum resolution with no compression (or conversion. to MPEG1 or MPEG2) on the fly. Use the Adobe Premier to open the uncompressed AVI file, do the NLE stuff, and encoding. TMPGEnc is also a very good encoder.

80 GB HD, dedicated only for capturing (Slave on Secondary IDE)

I think you mean "Slave on Primary IDE" here.

All the best,

[Gazorgan]

Huffyuv Codec runs maybe 30 GB/hour. MJPEG at 19/95% runs maybe 9 GB/hour? These are the 2 most comman capture codecs. Huffyuv is lossless, and mjpeg is virtually lossless(ie 'good enough' that you can't tell).


I don't like any of your cpature software ( have VDUB and Adobe 6.5). I use IUVCR(AVI) and PowerVCR(MPEG2). IUVCR is very impressive, but very clunky on it's interface. Powervcr is very user friendly, but limited to MPEG1/2 captures.

Thanks to all people that replied me

yesterday night I installed HuffYUV and tried it with ATI TV sw, it worked perfectly, I might say that now I know what is a Video codec

Anyway, I noticed I have a native - installed by whatever software - MJPEG codec installed, I chose it and had 60 % dropped frames, which means there is something wrong.
Is there any kind of specific MJPEG codec I should use, preferably frreware ?

Also, the most "user-friendly" capture sw for me is NeroVision, anyway, when I use the HuffYUV codec, I get 50% dropped frames, while this codec at ATI TV gets no dropped frames at all. It's clear for me that the system is fast enough, there might be a configuration issue with NeroVision, that by the way is the only mute capture sw as well.
Any guess ?

And most weird, Ulead Video Studio 6 is also very user friendly, but when I open the "compression" tab at capture mode there's no option to choose a CODEC ??!! AllI have as options are native YUVY and YUV2 - no list of codec appears !

I'd like to stick to either Ulead or NeroVision, but I have to find the solution to these issues;

Any help will be very apreciated,
Thanks very much for all people that replied,

Andre

P.S. yes, Capture 80 GB HD is at Primary Slave LOL !

[Will Hay]

It's never easy to detect the reason for lost frames but I would always recommend a second hard drive, (quick) formatted before each capture and used only for capturing.
Capturing to your primary (only) HDD is never wise.

I read your 'computer profile', rather than your spec contained within your post.
My mistake, I see you have two HDD's
Will

[aklendathu]

Hello andresalles,

I'm glad you're making progress. As for codecs, As far as I know, Huffyhuv is the only free one. However, PicVideo and Morgan MMJPEG are fairly inexpensive (less than $30). You can obtain trial versions of these codecs (however, there can only be ONE working MMJPEG codec in your system - whichever you install last will override any previous one).

The 'dropped frames' problem you mention with NeroVision and the 'native' MMJPEG codec may be that the capture software does not interface very well with the codecs in question.

Also, I'm fairly sure than you can capture the video with the ATI TV software and later import it to Ulead Video Studio for editing. Is this the full retail version or some OEM bundled software ? These are often crippled w.r.t. the full version - I am the proud(?) owner of three copies of Ulead Video Studio DV which can only capture and render DV...