Video editing - translation needed...

Off-topic
1

Firstly, thanks for all the help you guys have given me in the video editing department. I’ve been trying to find a way to change .wmv stuff to editable forms and came across something interesting but confusing. It seems like it’s saying you can change .wmv files but I don’t understand how. It mentions VirtualDub which I have and find really good to use.

Could someone please make sence of this?
[i]"Creating an AVI for Editing

The problem with the simple process described above is that the file may still not be editable with “Video for Windows”-based applications like VirtualDub. Microsoft has provided VfW drivers for early Windows Media codecs like MS MPEG-4 versions one through three, while hacked versions of Windows Media Audio versions one and two are available through various Internet resources.

Media streams encoded with newer formats like WM9 will require an intermediate conversion to a valid VfW format before being editable with VritualDub. Nearly any compatible compression codec can be utilized, but the nearly loss-less HuffYUV codec will be utilized in this example to avoid any massive data losses through excessive compression. VirtualDub can be used to filter and re-compress the resulting file to any codec of choice once the output has been processed with GraphEdit. Audio is being handled with IMA ADPCM (found under “Audio Compressors” filter section) due to similar compression loss concerns for this example. Again, as with the last example, connect the graphs, then click the green play button to generate the output file."[/i]

It came from here.

Thanks a lot,
Andrew

2

Windows Media format video (WMV files) is intended to be a final format and not an editable format. VirtualDub used to be able to read WMV files but Microsoft threatened legal action so that feature was removed.

Since Microsoft doesn’t want WMV files to be easily editable you have to get creative with the available software. Fortunately there are utilities available that will allow you to do it. One of them is GraphEdit, which just happens to be a utility distributed as part of the DirectX SDK (Software Development Kit) by Microsoft. Oh, I love the irony there. :slight_smile:

The reason for using the HuffYUV codec as the go-between format is because HuffYUV is a lossless format. Meaning that HuffYUV does not degrade or modify the pixels in the video during compression. Almost all other video codecs are lossy, meaning that they throw away and alter the pixels in the video to get a better compression ratio.

You can see the effect of using a lossy file format over and over by taking a high quality digital photo and saving it as a jpeg over and over and over. Make a copy of the photo. One will be the original and the other will be the test subject that gets mutilated. Open the test subject file in a program that can save as JPEG. Save the test subject as a JPEG at a lowish quality setting of 30 or below. Close the file and then re-open it. Save it again as a JPEG. Repeat for maybe 10 times or more. Now compare the original photo with the mutilated test subject. You should see noticeable degradation in the quality of the photo (vertical lines will get jagged, areas will get blotchy, etc). This same degradation of quality happens to video if you repeatedly use a lossy format when converting the video to another format or editing the video. That is why it is best to use the HuffYUV codec while editing the video and only convert it to a lossy format (like DivX) at the very end when you are done editing and are ready to distribute the video.

Here is a page with a definition of lossy and lossless compression:
<http://searchstorage.techtarget.com/gDefinition/0,294236,sid5_gci214453,00.html>

HuffYUV will give you about a 2:1 compression ratio. So your files will only be about half as big as raw uncompressed video. This still means HUGE file sizes. If you are going to be doing a lot of video with large files I would suggest using Windows 2000 or Windows XP and using an NTFS formatted partition for the video files. NTFS can handle AVI files that are larger than 2 GB. FAT32 has a limit of 2 or 4 GB (I can’t remember which) for AVI files which makes editing large AVI files more difficult than it needs to be. VirtualDub is smart enough to split large AVI files into 2 GB chunks when saving to a FAT32 partition. When saving to an NTFS partition VirtualDub will make AVI files as big as your free disk space allows.

One possible problem for you though is the official HuffYUV web page has disappeared. It used to be at <http://www.math.berkeley.edu/~benrg/huffyuv.html> but is no more. I can’t find the web page at a new location. But afterdawn.com still has HuffYUV available for download. <http://www.afterdawn.com/software/video_software/codecs_and_filters/huffyuv.cfm>

Here is another web page that describes using GraphEdit
<http://www.dvdrhelp.com/forum/userguides/98704.php>

Here is a page describing how to do it using a tool called STOIK Video Converter
<http://www.dvdrhelp.com/forum/userguides/115913.php>

You can download STOIK Video Converter from here (it’s free)
<http://www.stoik.com/downloads/downloads_frm.htm>

And another interesting option. Microsoft has a beta version of the WMV 9 codec that supports the VCM standard. This means that programs like VirtualDub and Adobe Premiere will be able to use the codec. I haven’t tried it yet. It just might let you open and edit WMV files in VirtualDub. Give it a try. You can download it from Microsoft here <http://www.microsoft.com/windows/windowsmedia/9series/codecs/vcm.aspx>

First try the new WMV 9 VCM codec to read and convert the video. If that doesn’t work then try the STOIK Video Converter. Use the GraphEdit solution as a last resort. I haven’t used any of these tools so I can’t say what will work or not.

Good luck.