1. Digital Processing of Analog Television Lior Zimet EE392J Final Project Winter 2002

2. Project Goals Digitize an analog NTSC signal and decode it in software Use digital processing to perform –Luminance and Chrominance separation –Color demodulation –Interlace to progressive conversion

3. System Block Diagram Display

4. NTSC – 1D Analog Signal

5. Composite Video Spectrum

6. Y/C Separation – 1D Comb Filter Resampling at 4xFsc will take advantage of the alternate phase in the color modulation Y/C separation can be done within the field Y =( (Y center +C center ) + (Y upper  C upper )) / 2 C = ((Y center +C center )  (Y upper  C upper )) / 2

7. Y/C Separation – 2D Adaptive Comb Filter 1D comb filter works perfectly only for vertically orientated structures in a picture 2D adaptive comb filter: –Weighs the upper line and lower line combing according to horizontal edge detection –Uses notch filter in cases where 1D fails

8. Y/C Separation – 3D Comb Filter In still image, pixels are identical from frame to frame The Chrominance phase is alternating Must be disabled when motion is present

9. Motion Artifacts Example

10. Y/C Separation – 3D Adaptive Comb Filter

11. Y/C Separation Example

12. Color Information

13. Color Demodulation

14. De-interlacing Merge fields or interpolate in the pixel domain Use motion detector to decide

15. Snell & Wilcox Pattern

16. Sequence from “Cheer Leader”

17. Decoded Frame from “Cheer Leader”

18. Motion Detection Apply small motion and large motion detection using adjacent fields Small MotionLarge Motion