ADS Technologies USBAV-708 INSTANT VIDEOMPX, User Manual

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The quality settings page allows configuration of decoder
options relating to the rendering of DivX video.
► Smooth playback
When a DivX video contains bi-directional
frames smooth playback makes use of a buffer
so the decoder need only decode one frame for
every frame it displays.
If the frame sequence were
1 I , 2 P , 3 B , 4 P , 5 B
the decoder would decode and buffer 1 I , decode
2 P and display 1 I , decode 3 B and display 3 B ,
decode 4 P and display 2 P , decode 5 B and display 5 B , ...
The last frame of the video may be dropped due to the buffer but
because only one frame is decoded at a time smooth playback
enhances performance for slower CPUs.
With smooth playback disabled b-frames are decoded at the same time
as the frames they reference and then displayed at the appropriate
time.
If the frame sequence were
1 I , 2 P , 3 B , 4 P , 5 B the decoder would
decode and display 1 I , decode 2 P and 3 B and display 3 B , wait and
display 2 P , decode 4 P and 5 B and display 5 B , wait and display 4 P .
No frames are dropped when smooth playback is disabled but greater
demands are placed upon the CPU.
For an explanation of frame orders refer to
Bi-directional encoding—
The ordering of frames .
►
YUV Extended
When enabled the decoder will output video in YV12 color mode. YV12
is the internal color format used by DivX and thus is the fastest method
of decoding as data can be sent directly to the video card.
When YUV Extended is enabled the
Brightness , Contrast and
Saturation controls are unavailable.
Quality settings