ee.Image.arrayPad

Pads the array values in each pixel to be a fixed length. The pad value will be appended to each array to extend it to given length along each axis. All bands of the image must be array-valued and have the same dimensions.
UsageReturns
Image.arrayPad(lengths, pad)Image
ArgumentTypeDetails
this: imageImageArray image to pad.
lengthsListA list of desired lengths for each axis in the output arrays. Arrays are already as large or larger than the given length will be unchanged along that axis
padNumber, default: 0The value to pad with.