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Altera_Forum
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16 years ago

De-interlacer with no frame buffer

Does the De-interlacer (BOB line duplication) work with no frame buffer? We have a good NTSC with embedded syncs as a source. We tested the source: CVI-->CVO and the image was fine. Now adding ...
Altera_Forum's avatar
Altera_Forum
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16 years ago

The deinterlacer does not handle NTSC very well because F0 and F1 have different sizes (respectively 244 lines and 243 lines). If you use the bob algorithm without buffering directly after the CVI then different things could happen depending on the parameterization. With "synchronize on F1" you will get a progressive 486 lines output, with "synchronize on F0" you will get a progressive 488 lines output, with "synchronize on both" you will end up with an output that alternates between these two dimensions.

You may place the clipper before the deinterlacer and clip the input fields to a common size (eg, with clip to height=240) or after the deinterlacer to clip the progressive frame (eg, with clip to height=480). What is the height supported by your output?