message: Generate informative error when attempting to execute SummaryImageOp with trivial dimensions.
  This bypasses a nullptr error that appears downstream due to referencing a length-zero array in a temporary buffer.
diff: @@ -78,6 +78,11 @@ class SummaryImageOp : public OpKernel {
  const int hw = h * w; // Compact these two dims for simplicity
  const int depth = static_cast<int>(tensor.dim_size(3));
  + OP_REQUIRES(c, hw > 0 && depth > 0,
  + errors::InvalidArgument(
  + "input tensor must have non-zero dims. Found: [",
  + batch_size, ", ", h, ", ", w, ", ", depth, "]."));
  +
  Summary s;
  if (tensor.dtype() == DT_UINT8) {
  // For uint8 input, no normalization is necessary
  