De-interlacing algorithms

De-interlacing algorithms can be sub divided into two broad categories:

1. Spatial Based
2. Motion Based

Some popular spatial based algorithms are:

• Simply weaving the odd field and doubling each line. (Produces aliasing)
• Averaging or blending both fields. (Produces ghosting)
• Edge dependent interpolation techniques between adjacent lines in odd-even fields. (Few artifacts if edge direction is inaccurate)

Some motion based algorithms are:

• Selective blending (or motion adaptive blending) basically only blend areas where there is motion and weaving where there is none. (Few artifacts if motion calculation is correct)
• Motion and edge adaptive algorithms combine edge interpolation techniques and motion adaptive blending. (Fewer artifacts at computational expense)
• Motion compensated algorithms can use the information to find the matching blocks in the neighboring fields. (Fewer artifacts at computational expense)

Be sure to check what algorithms your encoding software implements, it might have a great impact in your final video quality.