Problem 56478. IQpuzzler Preparation #3: Detect isolated groups of zeros in a matrix

Stefan Abendroth

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Return true if any small, rectangular shaped, isolated groups of zeros (size 1x1, 1x2, 2x1, 1x3, 3x1 or 2x2) are present in a matrix, with all vertically and horizontally adjacent elements being non-zero.
The matrix will always be 3-by-3 or larger.
Examples:
    11     2     3     2     9    10    10    11     6     7     4
    12     4    13     6     1    10     1    10     5     6     9
     2     8    13    12     0     0     0     5    10     9     9
    12    13     7    11    13     9     1    13    11    10     3
     9    13    11    13     9     3     2     1     3    10     2
==> true
    11     2     3     2     9    10    10    11     6     7     4
    12     4    13     6     1    10     1    10     5     6     9
     2     8    13    12     0     0     0     1    10     9     9
    12    13     7    11    13     0     1    13    11    10     3
     9    13    11    13     9     3     2     1     3    10     2
==> false
     7    10    13    11     5     5     4     1     2     3     8
    13     0     8     4     3    11    10     1     8    11     4
     5     0     2    11     4     8    10     7     7     5     9
     8     0     2     4     9     8     5    11     1     7     9
     3    12     4    13     7    12     8    13     5     3    10
==> true
Background:
This function or variations of it may be useful in some board games like Go, or in the upcoming IQpuzzler challenge.
Hint:
The built-in function conv2 may be helpful for your implementation.