I've searched the forums and have not found an answer to this question, and apologize in advance if one already exits. My question is in regards to SD (anamorphic) and HD video in After Effects...or any video editing/compositing software. If I take SD video and import it into a HD composition say 720p and scale it up to fit the comp - what happens to the SD video? Does it resample the pixel info and, if so, does it become 720? If it's 720 does that technically make it HD (as ridiculous as that sounds)? I know that scaling SD to fit HD is going to result in some fuzzy video, but I guess my question is: what makes HD...HD?
Or another example: playing a DVD in a blu-ray player. The player upscales the DV to fill my HD tv but, again, when is it considered HD (other than it just looks more awesome)?
I'm still having a somewhat difficult time understanding this. Projecting video onto a wall and having the pixel dimensions increase in size make senses, but I'm still having a hard time understanding what happens to the pixels on a computer screen when SD is upscaled. As a test I took a SD video, imported it into a 720 x 1080 comp in After Effects and scaled it up to fit the comp. Yes, it didn't look too good but when I exported one of the frames and took it into Photoshop I counted out 720 x 1080 pixels (didn't seem as though the pixel size increased).
A rule of thumb for HD is this: anything that is larger than SD is HD. So, when you exported out the frame you were exporting out an HD comp regardless of the size of the image you used in it - so it would be HD.