Specifying Pixel Depths

Hosts and plugins flag whether whether they can deal with input/output clips of differing pixel depths via the kOfxImageEffectPropSupportsMultipleClipDepths property.

If the host sets this to 0, then all effect's input and output clips will always have the same component depth, and the plugin may not remap them.

If the plugin sets this to 0, then the host will transparently map all of an effect's input and output clips to a single depth, even if the actual clips are of differing depths.

In the above two cases, the common component depth chosen will be the deepest depth of any input clip mapped to a depth the plugin supports that loses the least precision. eg: if a plugin supported 8 bit and float images, but the deepest clip attached to it was 16 bit, the host would transparently map all clips to float.

If both the plugin and host set this to 1, then the plugin can, during the kOfxImageEffectActionGetClipPreferences , specify how the host is to map each clip, including the output clip. Note that this is the only case where a plugin may set the output depth.