Datasheet

Functional Description
14
SLES099C—March 2007TVP5147PFP
2.2.2.2 Y/C Separation
Y/C separation can be done using adaptive 5-line (5-H delay) comb filters or a chroma trap filter. The comb
filter can be selectively bypassed in the luma or chroma path. If the comb filter is bypassed in the luma path,
then chroma trap filters are used which are shown in Figure 2−8 through Figure 2−11. TI’s patented adaptive
comb filter algorithm reduces artifacts such as hanging dots at color boundaries. It detects and properly
handles false colors in high-frequency luminance images such as a multiburst pattern or circle pattern.
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f − Frequency − MHz
No Notch Filter
Notch 2 Filter
Amplitude − dB
Figure 2−8. Chroma Trap Filter Frequency
Response, NTSC Square Pixel Sampling
Notch 1 Filter
f − Frequency − MHz
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No Notch Filter
Notch 3 Filter
Notch 1 Filter
Amplitude − dB
Figure 2−9. Chroma Trap Filter Frequency
Response, NTSC ITU-R BT.601 Sampling
Notch 2 Filter
Notch 3 Filter
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f − Frequency − MHz
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Amplitude − dB
Figure 2−10. Chroma Trap Filter Frequency
Response, PAL ITU-R BT.601 Sampling
Figure 2−11. Chroma Trap Filter Frequency
Response, PAL Square Pixel Sampling
f − Frequency − MHz
Amplitude − dB
No Notch Filter
Notch 2 Filter
Notch 1 Filter
Notch 3 Filter
No Notch Filter
Notch 2 Filter
Notch 1 Filter
Notch 3 Filter