1 files changed, 99 insertions, 4 deletions
diff --git a/vespajlib/src/main/java/com/yahoo/tensor/serialization/JsonFormat.java b/vespajlib/src/main/java/com/yahoo/tensor/serialization/JsonFormat.java
index fa2094e9d2a..9eb9cb06666 100644
--- a/vespajlib/src/main/java/com/yahoo/tensor/serialization/JsonFormat.java
+++ b/vespajlib/src/main/java/com/yahoo/tensor/serialization/JsonFormat.java
@@ -103,10 +103,17 @@ public class JsonFormat {
         if ( ! (builder instanceof IndexedTensor.BoundBuilder))
             throw new IllegalArgumentException("The 'values' field can only be used with dense tensors. " +
                                                "Use 'cells' or 'blocks' instead");
+        IndexedTensor.BoundBuilder indexedBuilder = (IndexedTensor.BoundBuilder)builder;
+        if (values.type() == Type.STRING) {
+            double[] decoded = decodeHexString(values.asString(), builder.type().valueType());
+            for (int i = 0; i < decoded.length; i++) {
+                indexedBuilder.cellByDirectIndex(i, decoded[i]);
+            }
+            return;
+        }
         if ( values.type() != Type.ARRAY)
             throw new IllegalArgumentException("Excepted 'values' to contain an array, not " + values.type());
 
-        IndexedTensor.BoundBuilder indexedBuilder = (IndexedTensor.BoundBuilder)builder;
         MutableInteger index = new MutableInteger(0);
         values.traverse((ArrayTraverser) (__, value) -> {
             if (value.type() != Type.LONG && value.type() != Type.DOUBLE)
@@ -143,11 +150,99 @@ public class JsonFormat {
                            decodeValues(value, mixedBuilder));
     }
 
+    private static byte decodeHex(String input, int index) {
+        int d = Character.digit(input.charAt(index), 16);
+        if (d < 0) {
+            throw new IllegalArgumentException("Invalid digit '"+input.charAt(index)+"' at index "+index+" in input "+input);
+        }
+        return (byte)d;
+    }
+
+    private static double[] decodeHexStringAsBytes(String input) {
+        int l = input.length() / 2;
+        double[] result = new double[l];
+        int idx = 0;
+        for (int i = 0; i < l; i++) {
+            byte v = decodeHex(input, idx++);
+            v <<= 4;
+            v += decodeHex(input, idx++);
+            result[i] = v;
+        }
+        return result;
+    }
+
+    private static double[] decodeHexStringAsBFloat16s(String input) {
+        int l = input.length() / 4;
+        double[] result = new double[l];
+        int idx = 0;
+        for (int i = 0; i < l; i++) {
+            int v = decodeHex(input, idx++);
+            v <<= 4; v += decodeHex(input, idx++);
+            v <<= 4; v += decodeHex(input, idx++);
+            v <<= 4; v += decodeHex(input, idx++);
+            v <<= 16;
+            result[i] = Float.intBitsToFloat(v);
+        }
+        return result;
+    }
+
+    private static double[] decodeHexStringAsFloats(String input) {
+        int l = input.length() / 8;
+        double[] result = new double[l];
+        int idx = 0;
+        for (int i = 0; i < l; i++) {
+            int v = 0;
+            for (int j = 0; j < 8; j++) {
+                v <<= 4;
+                v += decodeHex(input, idx++);
+            }
+            result[i] = Float.intBitsToFloat(v);
+        }
+        return result;
+    }
+
+    private static double[] decodeHexStringAsDoubles(String input) {
+        int l = input.length() / 16;
+        double[] result = new double[l];
+        int idx = 0;
+        for (int i = 0; i < l; i++) {
+            long v = 0;
+            for (int j = 0; j < 16; j++) {
+                v <<= 4;
+                v += decodeHex(input, idx++);
+            }
+            result[i] = Double.longBitsToDouble(v);
+        }
+        return result;
+    }
+
+    private static double[] decodeHexString(String input, TensorType.Value valueType) {
+        switch(valueType) {
+            case INT8:
+                return decodeHexStringAsBytes(input);
+            case BFLOAT16:
+                return decodeHexStringAsBFloat16s(input);
+            case FLOAT:
+                return decodeHexStringAsFloats(input);
+            case DOUBLE:
+                return decodeHexStringAsDoubles(input);
+            default:
+                throw new IllegalArgumentException("Cannot handle value type: "+valueType);
+        }
+    }
+
     private static double[] decodeValues(Inspector valuesField, MixedTensor.BoundBuilder mixedBuilder) {
-        if (valuesField.type() != Type.ARRAY)
-            throw new IllegalArgumentException("Expected a block to contain a 'values' array");
         double[] values = new double[(int)mixedBuilder.denseSubspaceSize()];
-        valuesField.traverse((ArrayTraverser) (index, value) -> values[index] = decodeNumeric(value));
+        if (valuesField.type() == Type.ARRAY) {
+            valuesField.traverse((ArrayTraverser) (index, value) -> values[index] = decodeNumeric(value));
+        } else if (valuesField.type() == Type.STRING) {
+            double[] decoded = decodeHexString(valuesField.asString(), mixedBuilder.type().valueType());
+            for (int i = 0; i < decoded.length; i++) {
+                values[i] = decoded[i];
+            }
+        } else {
+            throw new IllegalArgumentException("Expected a block to contain a 'values' array");
+        }
         return values;
     }