Wednesday, August 29, 2007

Perspective Reflections - Inkscape Screencast


I've uploaded my latest Inkscape screencast (Episode 35). This one describes a neat method of creating reflections using a simple black to white mask. I discovered this neat trick at Nicu's great blog.

While I've made reflections using Inkscape in the past, I've always had two problems. First, if the group of objects to be reflected consisted of multiple colours, using a simple opacity gradient was quite a pain. Second, creating a realistic looking reflection for an object in perspective (particularly photos) was very difficult. The one that we use on the screencaster LCD monitor thumbnail (at the top of this post) is really faked with a white opacity gradient. The problem being that if I changed the background to anything but white, you'd suddenly see the retardedness of it all. ;)

So the mask method eliminates these two problems and makes creating reflections of more complex objects (including perspectives) much easier and more elegant.

Hope you enjoy it.

For those who care about the mechanics of screencasting, this was actually the first one that I created solely with recordmydesktop, mencoder, and Audacity - although I did use an ffmpeg one-liner to extract a screenshot for the thumbnail (anybody know how to do that with mencoder/mplayer?). I think the quality is better and the workflow is definitely easier and more logical. Big thanks to Heathenx for helping me out with this stuff.

But it wasn't completely without problem. You will notice some weird artifacting that occurs about 2 or 3 seconds into my sped-up intro. This wasn't in the original ogg capture, but occurred somewhere during the post-processing. I thought it might disappear by the end - but no such luck. ;) I've decided to leave it there for the time being and will correct it and replace the files when I can.. ie. not tonight. ;)

One other thing is that I haven't yet put this one up on YouTube. It's about 12min long, so I'm gonna have to split it up like I did with Episode 26. I'd like to do it with mencoder as well this time, so in the next couple of days I expect to have the two-parts finished and up on YouTube as well.

1 comments:

Ian said...

After dealing with my own screencast-recording Hell, I have even more respect for you (and your partner in crime) for creating all these Inkscape videos. I played with xvidcap, recordMyDesktop, ffmpeg, mencoder, audacity, avidemux, kino and probably others that I am missing. The whole process took so many more hours than I expected (and I doubled my original expectation...). The end quality was only so-so because I couldn't get anything to cooperate. I couldn't get any capturing software to get audio at the same time, so I recorded the audio separately, but then I couldn't listen to the audio I had recorded, so I couldn't correct any of it. Then ffmpeg wouldn't handle the original ogg video correctly, so I had to switch to mencoder... long story short, I'm done. It's not great, but I'm done. So props to you for making such great videos regularly.