100fps: How to deinterlace Video the right way. Examples, Tricks, Comparisons

How does resizing/rotating affect picture quality?

 

Original 320x240
Clear blocks and diagonal lines
        
100% -> 1000% -> 100%
Resized up to 1000% (320x240->3200x2400) and then back to 320x240 again
        
43 degrees rotated
        
45 degrees rotated
        
Reduced the width (as you do when resizing from 720x288 to 384x288)
As you see the white borders appear only to the left/right, not to the top/bottom of the black blocks.
        
Resized up to 200% (320x240->640x480) and back to 320x240
        

 

Resized down to 50% (320x240->160x120)
        
Resized up to 200% (320x240->640x480)
As you see, bicubic resizing (even if it's upsizing) produces white borders.
        

 

Conclusion: Try not to resize. Neither up-resize nor down-resize. You will lose quality.
In practice this could mean for example: Crop two horizontal lines instead of resizing from 384x290 to 384x288.

Click here to see how height x width can be better than HEIGHT x WIDTH.

100fps: How to deinterlace Video the right way. Examples, Tricks, Comparisons