How can I use the compositor on the result of the sequencer? I recently ran a renderfarm on a file with some compositing setup, but I forgot to set the composite output back to the Composite node instead of the Viewer I was temporarily using. Since the node setup didn't require anything besides the image data (i.e., no Z-buffer, object IDs, etc.) I figured that I could just run the compositor on each frame individually. However, this proved to be somewhwat difficult.

It seems that the sequencer is run after the compositor (despite their non-exclusivity in the Post Processing panel), so my idea to use an image strip in the sequencer for all the images that I already rendered didn't work&mdash;the render just copied the images into a new directory.

The Movie Clip node doesn't seem to accept an image strip as input, either, so that was not an option.

What I ended up doing was sequencing the animation to a movie file, then piping that into the Movie Clip node in the compositor. However, this required extra time, extra storage, and it rendered the default scene every frame before compositing, only to ignore the result.

Is there a way to use Blender's compositor either directly on an image sequence, or in conjunction with the video sequencer?
To use the rendered image sequence as input in the compositor, use the Image node. Select any file within the image sequence as input. Change the node's type from Single Image to Image Sequence, then set the sequence's length and first frame.