What visible defects will an image from a SAA7129 ( or similar ) video encoder have if no video reconstruction filter is connected to encoder's DAC outputs?
Video reconstruction filter is basically low pas filter that cuts-off anyting above the baseband video signal (or its components). Not using this filter will leave all by-product of D/A conversion.
The result will be very individual, and will depend on the configuration of next stages. You may have "noisy" and/or "ghosty" picture ..