Blackmagic Design Fusion save image from active comp view

fusion_save_active_view_image.py

import itertools


def iter_viewers(comp):
    """Iterate GLPreview views for Composition.

    It prefers the active view first, then yields views
    from the current frame (active window), then from the comp,
    then from floating views last.
    
    It does not return the "Monitor view" however.
    
    Yields:
        GLImageViewer: image viewers for the comp
    
    """
    
    processed = set()

    # Prefer current view
    frame = comp.CurrentFrame
    view = frame.CurrentViewer
    if view:
        yield "Active view", view
        processed.add(str(view))
        
    for name, preview in itertools.chain(
        # all views for current active window/frame
        frame.GetPreviewList().items(),
        # all comp views
        comp.GetPreviewList().items(),
        # floating views for a comp are only returned by `fusion.GetPreviewList()
        # so we will need to iterate those as a last resort too
        fusion.GetPreviewList().items()
    ):
        # Avoid duplicates
        key = str(preview)
        if key in processed:
            continue
        processed.add(key)
    
        # Only allow GLPreview
        if preview.GetID() != "GLPreview":
            continue
            
        view = preview.View
        if not view:
            continue
        
        if str(view.Composition()) != str(comp):
            continue
            
        for viewer in itertools.chain([view.CurrentViewer], view.GetViewerList().values()):
            if not viewer:
                # CurrentViewer might be None
                continue
        
            key = str(viewer)
            if key in processed:
                continue
            processed.add(key)
            
            yield name, viewer    


def get_comp_thumbnail(comp, destination):
    """Save current image from first active viewer from Composition"""
    for name, viewer in iter_viewers(comp):
        print(viewer.GetID())
        if viewer.SaveFile(destination):
            # Image only gets saved if has a tool set and only returns
            # True in the case it has a valid image to save
            print(f"Saved {name}: {destination}")
            break
    else:
        print("Not saved")


get_comp_thumbnail(fusion.CurrentComp, destination="E:/test.jpg")