Implementation of ctc beam search decoder op in custom op fashion.

PiperOrigin-RevId: 207210333

1 files changed, 12 insertions, 0 deletions

diff --git a/tensorflow/contrib/lite/toco/graph_transformations/propagate_array_data_types.cc b/tensorflow/contrib/lite/toco/graph_transformations/propagate_array_data_types.cc
index f033ee013e..c8310161cb 100644
--- a/tensorflow/contrib/lite/toco/graph_transformations/propagate_array_data_types.cc
+++ b/tensorflow/contrib/lite/toco/graph_transformations/propagate_array_data_types.cc
@@ -215,6 +215,18 @@ bool PropagateArrayDataTypes::Run(Model* model, std::size_t op_index) {
       model->GetArray(op->outputs[0]).data_type = on_value_type;
       break;
     }
+    case OperatorType::kCTCBeamSearchDecoder: {
+      CHECK_EQ(op->inputs.size(), 2);
+      // All outputs (sparse tensors) are int32s (although tf uses int64s)
+      // except the last one (log probabilities) is float.
+      const int output_size = op->outputs.size();
+      for (int i = 0; i < output_size - 1; ++i) {
+        model->GetArray(op->outputs[i]).data_type = ArrayDataType::kInt32;
+      }
+      model->GetArray(op->outputs[output_size - 1]).data_type =
+          ArrayDataType::kFloat;
+      break;
+    }
     default: {
       // These operators produce outputs with the same type as their 1st input
       CHECK_GT(op->inputs.size(), 0);