ImageDisplacements
ImageForwardTransformation
ImageFeatureTrack
FeatureExtraction
FrameListVideo
DominantColors
ImageAssemble
Blend
ListAnimate

Image Processing
Computer Vision

Create a Slow Motion Video with Optical Flow

Interpolate between existing image frames to create a slow motion sequence

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Consider a series of images or frames:

In[1]:=

original=ResourceData["Example: Create a Slow Motion Video with Optical Flow","ImageList"];

Make an animation with the original images:

In[2]:=

FrameListVideo[original]

Out[2]=

Compute the displacement between consecutive images. To use optical flow on images, convert

indexcoordinates

to image coordinates:

In[3]:=

flows=Map[vecFieldTranspose@Reverse[vecField],ImageDisplacements[original,MaxIterations1]/2];

New, interpolated images are constructed by warping original frames according to the optical flow. Apply

ImageForwardTransformation

to the first image in the list to construct a new frame:

In[4]:=

ImageForwardTransformation

,(#+Extract[flows〚1〛,Ceiling[#]])&,

...



Out[4]=

Use

DominantColors

to select a background color for the interpolated image:

In[5]:=

bg=First@DominantColors[First@original,1]

Out[5]=

Add the background color and recreated the interpolated image:

In[6]:=

ImageForwardTransformation

,(#+Extract[flows〚1〛,Ceiling[#]])&,



Out[6]=

Define a function for the transformation:

In[7]:=

vecTrafo[xy_,motion_]:=xy+Extract[motion,Ceiling[xy]];

Use the transformation function to construct the interpolated frames for the list of images:

In[8]:=

oflow=TableImageForwardTransformationoriginali,vecTrafo[#,flows〚i〛]&,

,{i,Length@original-1};

Insert the interpolated images into the final sequence:

In[9]:=

slowmo=Riffle[original,oflow];

Animate the result and compare it with a simple blending-based reference:

In[10]:=

compresults=MapThreadImageAssembleShow#1,

Graphics[

]

,Show#2,

Graphics[

]

&,{slowmo,Riffle[original,Blend/@Partition[original,2,1]]};FrameListVideo[compresults]

Out[10]=

Related Symbols

ImageDisplacements
ImageForwardTransformation
ImageFeatureTrack
FeatureExtraction
FrameListVideo
DominantColors
ImageAssemble
Blend
ListAnimate

Publisher Information

Contributed by: Wolfram Staff