Patent ID: 11928759
Assignee: HUAWEI TECHNOLOGIES CO., LTD.
Field: Computer technology (Electrical engineering)
Classification: CPC G | IPC G

Claim 0:
1. A method of generating vector line drawings comprising:
obtaining an input image, the input image being a raster image of a ground-truth drawing;
initiating a blank canvas image equal in size to the input image;
using a vector line drawing network, generating a vector line drawing over a series of time steps by, for each time step in the series of time steps:
obtaining a defined window position and a defined window size and defining a dynamic drawing window accordingly;
obtaining an image patch from the input image;
obtaining a canvas patch from the canvas image;
the image patch and the canvas patch being obtained from the input image and the canvas image, respectively, based on the defined window position and defined window size of the dynamic drawing window, by:
resampling the dynamic drawing window into spatial bins based on the defined window size of the dynamic drawing window and a resampling size;
setting sampling points inside each bin;
computing values for the sampling points by bilinear image interpolation; and
extracting the image patch and the canvas patch from the input image and the canvas image, respectively;

generating, using a stroke generator, a stroke action for a current time step, wherein the image patch and the canvas patch are provided as inputs to the stroke generator, the stroke action including positional values for computing a set of stroke parameters;
defining the defined window position and the defined window size for a next time step based on the stroke action generated for the current time step;
rendering a rendered stroke image using the set of stroke parameters computed from the positional values; and
pasting the rendered stroke image on to the canvas image based on the position and size of the dynamic drawing window; and
outputting the generated vector line drawing.