Create a Frame Counter¶

Problem¶

You want to overlay a frame counter on a video.

Solution¶

To create a frame counter for a video we need to create a text annotation of the frame number and composite the frame number on the appropriate frame.

#Set up the decoder
decoder = Draft.VideoDecoder( "path/to/clip.mov" )
image = Draft.Image.CreateImage( 1, 1 )
textInfo = Draft.AnnotationInfo()

#Set up encoder
encoder = Draft.VideoEncoder( "path/to/save/video.mov" )

while decoder.DecodeNextFrame( image ):
frameText = Draft.Image.CreateAnnotation( str( frameNumber ), textInfo )

#composite annotation onto frame
anchor = Draft.Anchor.SouthEast
compOp = Draft.CompositeOperator.OverCompositeOp
image.CompositeWithAnchor( frameText, anchor, compOp )

#encode the frame
encoder.EncodeNextFrame( image )

encoder.FinalizeEncoding()


Discussion¶

Draft gives you a lot of freedom when creating a frame counter. Firstly, You can set frameNumber to start at any number you want. For example, you can make the frame count from the start of the reel or some other number like a timecode.

Also, you can set the frame number to be padded with zeros like this: 0012. Just change CreateAnnotation() to:

CreateAnnotation( "%04d" % frameNumber, textInfo )


The number after the zero is the total number of digits that will appear.

Secondly, the size, font and colour can be set to anything by changing textInfo (see the entry on Create Text Annotation for more information).

Finally, you can change the position of your frame counter by changing the Anchor. In this example, the frame counter will be put in the bottom right corner. By changing the Anchor you can make the frame counter appear anywhere on the frame such as the top right corner with a NorthEast anchor.