Grass Valley Media Conversion - Manual (Page 29)

Media Conversion Software Animation Builder
Miranda Technologies Ltd Page 29
The second approach is to render 25 frames at 720x576, with each frame
containing valid data interleaved for both fields. If one of these images is
loaded and viewed as a still, you will typically see tearing artefacts on the
edges of horizontally moving objects, due to the interleaving. As Animation
Builder reads these files, it splits the frame image into two separate field
images. The interlace emulation of Animation Builder allows both options to
be previewed and the correct one selected without transferring the animation
to an Imagestore.
Animation Duration
Imagestore Intuition
Because Intuitions read animations directly from the disk during playout, the
duration of an animation is constrained only by the disk space available on
the Intuition system. Using the Animation Builder’s optional cropping feature
is recommended to reduce the size of the animation files.
Other Imagestore systems
The maximum duration of an animated sequence is not determined by the
Animation Builder but by the video memory of the Imagestore used for
playout. The basic video memory for Imagestore is 2 x 32Mb. – 32Mb for
Preview and 32Mb for Programme (or foreground and midground, in cascade
mode). 32 Megabytes gives roughly 20 full frames of PAL video (around
0.75 seconds). Animations that use less than the full screen area can have
proportionately more frames. An animation of around 1/64
th
(or 1/8
th
by 1/8
th)
of full screen could have a maximum duration of around 48 seconds.
Video memory upgrade options for Imagestore can extend the video memory
to 2 x 64Mb, 2 x 256Mb and 2 x 512Mb (HDTV), increasing the maximum
animation duration accordingly.
Imagestore units can loop animations to allow them to run continuously. In
this case, the video memory needs to hold a single loop of the animation.
Animation Builder can optionally use selective cropping to crop each frame
independently to reduce the playout memory requirements.