Once I've Already Shot the Video, Can I Crop the Bottom Half of it and/or Zoom in On My Subject?

December 12, 2007 9:26 AM

How can I a) crop off the whole bottom half of a video, b) zoom in on my subject after I've already made the video, or c) hide the face of someone in the video? While I'm asking, how about taking a video made on a Canon (designed for stills, so their video actual size is small, which means it pixilates horribly when you put it on youtube) and making it stay actual size when placed on the web? I'm on a windows notebook and hoping any of this is even possible. Thanks!

What's happened is that I've found myself in a position where I will be videoing and publishing daily, and I am no expert on video. That's fine, because I can learn.

But in the meantime, I will be starting with videos that are already made, and I need to get them good enough to publish. In some of the cases, I need to hide the identity of people or locations in the already-made videos (nothing nefarious, just don't have permission for the already made ones for the people/places), and in the canon stuff, just need to make them look decent. I'm sure my ignorance shows here, but I pick up quickly once I know what to do!

I cannot switch to mac or final cut pro at this time cuz those funds aren't in the budget for this not-for-profit thing, but any pointers on windows software/techiniques/common sense would be much appreciated.

Thanks!

posted by thewhynotgirl to media & arts (5 comments total)

While digital digest's how-tos are more focused on conversions, there are some writeups on editing using VirtualDub, which is nice and free. Doom9 has a guide too.

Or read the plain and simple "how do I crop?" from the faq.

For the blurring I'm sure there's a blur or pixelation filter out there but you could also try (mis)using the filter LogoAway, which is in a pack here among other places. I am 99% sure that if you tell it to interpolate the hell out of a non-existant logo in the place where a person's face is you'll get an undecipherable image.
posted by phearlez at 10:22 AM on December 12, 2007

Right after I posted this I found this facemask filter for Transcode.

While Transcode is a unix app, you could do what I do for my linux-based development and just run Microsoft's Virtual PC and run Fedora inside it. Not necessarily a task for the timid but your limited budget limits some of your choices...
posted by phearlez at 10:36 AM on December 12, 2007

Phearlez, thank you for taking the time to add not one, but two posts to help me out!

I've checked out the links you provided, and on the Doom9 link I found a page that offers this gem:

Cropping works by the use of the Crop function in Avisynth. It takes 4 arguments: Left, Top, Horizontal output size and vertical output size. Here's an example which crops the black bars from a 16:9 1:2.35 NTSC stream:

Crop(0,60,720,360)

This will crop the top 60 line of the video, plus the bottom 60 lines (remember that the video stream originally was 720x480, so if you crop the top 60 lines away and take the next 360 lines that cuts off the bottom 60 as well - 60 (black) + 360 (video) + 60 (black) = 480) If you add this line to the script above you'll now get a 720x360 video stream which has no black bars, just the video data. In recent AviSynth versions, an alternative way to crop was added: if the third and fourth parameter are negative, they serve as crop values as well. So, the above crop line is equal to this:

Crop(0, 60, 0, -60)

Now, let me say that I want to make it clear that I am looking to crop the horizontal bottom of the entire video, whereas some of your post looks as though it refers to cropping the beginning/end of the video. I'm just saying that to clarify.

Noticing that this question has been favorited by 4 members already (wow, neat!), I thought I'd detail what I've found ...

149;The page found via your helpful link seems to do just what I will want, although it looks both intimidating and straightforward (lol!) to this newbie -- I'm kinda praying that I'll find it easy to understand once I start fiddling with it.

149;The page includes direct download links for all software (freeware :) needed.

149;And it includes a link to Avisynth's main page, which happens to be a mediawiki with delectable newbie handholding tutor/explanation goodness.

149;Through all this, I also learned some proper terminology, which should be quite helpful for better searching

In short, the query I'd secretly voted least-possible, looks to be easily possible after all, and that's mega cool. So thanks :)

Still open to help for post production zooming, and for shrinking the canon video for nonpixilated youtube posting. But I'm pretty happy at this moment: Did I say thanks? :)
posted by thewhynotgirl at 12:02 PM on December 12, 2007

Provided you can't lay your hands on one of the basic "timeline with effects" editors targeted at home movie editing (often free with DVD burners, etc), you might like to look at ZS4. Have never used it myself, but it's worth a look. Beyond that, a lot of your choice of cheap & simple editors is going to come down to what your source & target formats are (e.g. MPEG-2, MPEG-4, .wmv, etc).

Something to convert video formats - there's a million different ones, and inevitably whatever tools you use will only handle certain formats - will come in handy. I kinda like SUPER video converter (actually, no I don't - it's a nasty 'orrible piece of crap with a stupid UI, but is handy because of the wide range of formats it can import/export).

Certainly, everything you want to do can be done in VirtualDub, AVIsynth, etc - and, originally, I used them for everything - but anything beyond basic cutting and cropping is best and easiest done in a real timeline-with-effects editor.

(I use EditStudio myself, but I'm mainly playing with DVB-T MPEG-2 streams. And I don't even know if it's still available...)

YouTube is horribly pixellated crap anyway - it's the nature of the beast; small (320x240) video at low bitrate is going to look terrible regardless. There's not much you can do except embrace its limitations and work around them - start with the cleanest source possible, smooth the hell out of it if necessary to remove any noise and / or edges that'll just eat bits, use stable shots with minimal background movement, and accept it'll look like arse on rapid pans and hand-held shots.

On preview:
If your Canon video is smaller than YouTube's 320x240, and you want to keep it "actual size", then all you can do is add a plain borders all around until it is 320x240
posted by Pinback at 12:16 PM on December 12, 2007

You can download a fully functioning version of After Effects from Adobe (30 day limit). Everything you're describing can be done very easily in AE.
posted by Scoo at 1:50 PM on December 12, 2007