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Hi,
there is plenty of information about the topic of interlacing in the context of video technology, therefore I’ll keep it short and assume you already know what it’s all about.
While being a huge burden in my opinion, one still has to deal with interlaced media, because basically this is what most camcorders produce.
What’s interesting though is the approach that developers have taken to display interlaced media on a progressive computer screen. They display 25 frames of images, often with crude smothing filters applied to overcome the artefacts, introduced by the concurrent display of two images that take place at different times.
Here an example of mplayer showing a interlaced image without any filters.
And here an image from the little player software that I began to write:
Actually a still image is not as useful, because the difference is really when you watch at the playback. I already blogged wrote about that approach, but I will explain it once again.
This player software simple plays back video at a rate of 50 frames per second, and using each field of an interlaced frame as a full frame. The advantage is clear, espacially for shacky camcorder footage, because there is much more “motion” information in the video, therefore the playback feels “smoother”.
The approach taken is simple, each frame is converted to two opengl textures, where once only the even and then only the odd scanlines are taken. then the texture is displayed, using opengl to scale them into the correct aspect ratio.
And in other news, I’ve started work on a simple “Scale, Crop and Tilt” plugin, see a screenshot here:
Have fun,
-Richard