ADS Technologies USBAV-708 INSTANT VIDEOMPX, Руководство пользователя

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The most visible artifact occurring in low-
bitrate DivX video is called
blocking , and
appears as small 8x8 squares in the video.
The artifact is caused by the DCT
algorithm used by DivX to encode the
image, and becomes strongest where
video is encoded at very low bitrates due to
high quantization.
De-blocking blends the transition along the block edges so that individual blocks
become less apparent.
Ringing is another artifact caused by the DCT algorithm. Ringing appears as an
outline or shadowing around contrasting edges in the picture.
Ringing is harder to see than blocking and
requires more computation to correct. By
default the encoder will apply full de-
blocking before applying any de-ringing,
depending on real-time decoding
performance.
The DivX decoder can automatically adjust the level of de-
blocking and de-ringing based upon your computers real-
time playback performance. This prevents the decoder
dropping frames if the CPU becomes overloaded.
Automatic de-blocking is enabled when
Partial auto post-
processing is selected. Automatic de-blocking and de-
ringing are enabled when
Full automatic post-processing is
selected.
De-blocking
De-ringing
Automatic post-processing