Add C# API for Dolphin CTC models (#2089)

.github/scripts/test-dot-net.sh

@@ -39,6 +39,9 @@ rm -rfv sherpa-onnx-pyannote-*
 
 cd ../offline-decode-files
 
+./run-dolphin-ctc.sh
+rm -rf sherpa-onnx-dolphin-base-ctc-multi-lang-int8-2025-04-02
+
 ./run-fire-red-asr.sh
 rm -rf sherpa-onnx-fire-red-asr-*
 

.github/workflows/c-api.yaml

@@ -97,7 +97,7 @@ jobs:
             readelf -d ./$name
           fi
 
-          curl -SL -O https://github.com/k2-fsa/sherpa-onnx/releases/download/asr-models/sherpa-onnx-dolphin-base-ctc-multi-lang-int8-2025-04-02
+          curl -SL -O https://github.com/k2-fsa/sherpa-onnx/releases/download/asr-models/sherpa-onnx-dolphin-base-ctc-multi-lang-int8-2025-04-02.tar.bz2
           tar xvf sherpa-onnx-dolphin-base-ctc-multi-lang-int8-2025-04-02.tar.bz2
           rm sherpa-onnx-dolphin-base-ctc-multi-lang-int8-2025-04-02.tar.bz2
 

.github/workflows/cxx-api.yaml

@@ -103,7 +103,7 @@ jobs:
             readelf -d ./$name
           fi
 
-          curl -SL -O https://github.com/k2-fsa/sherpa-onnx/releases/download/asr-models/sherpa-onnx-dolphin-base-ctc-multi-lang-int8-2025-04-02
+          curl -SL -O https://github.com/k2-fsa/sherpa-onnx/releases/download/asr-models/sherpa-onnx-dolphin-base-ctc-multi-lang-int8-2025-04-02.tar.bz2
           tar xvf sherpa-onnx-dolphin-base-ctc-multi-lang-int8-2025-04-02.tar.bz2
           rm sherpa-onnx-dolphin-base-ctc-multi-lang-int8-2025-04-02.tar.bz2
 

c-api-examples/CMakeLists.txt

@@ -56,6 +56,9 @@ target_link_libraries(fire-red-asr-c-api sherpa-onnx-c-api)
 add_executable(sense-voice-c-api sense-voice-c-api.c)
 target_link_libraries(sense-voice-c-api sherpa-onnx-c-api)
 
+add_executable(dolphin-ctc-c-api dolphin-ctc-c-api.c)
+target_link_libraries(dolphin-ctc-c-api sherpa-onnx-c-api)
+
 add_executable(moonshine-c-api moonshine-c-api.c)
 target_link_libraries(moonshine-c-api sherpa-onnx-c-api)
 

c-api-examples/dolphin-ctc-c-api.c

@@ -6,7 +6,7 @@
 // This file demonstrates how to use Dolphin CTC model with sherpa-onnx's C API.
 // clang-format off
 //
-// wget https://github.com/k2-fsa/sherpa-onnx/releases/download/asr-models/sherpa-onnx-dolphin-base-ctc-multi-lang-int8-2025-04-02
+// wget https://github.com/k2-fsa/sherpa-onnx/releases/download/asr-models/sherpa-onnx-dolphin-base-ctc-multi-lang-int8-2025-04-02.tar.bz2
 // tar xvf sherpa-onnx-dolphin-base-ctc-multi-lang-int8-2025-04-02.tar.bz2
 // rm sherpa-onnx-dolphin-base-ctc-multi-lang-int8-2025-04-02.tar.bz2
 //

cxx-api-examples/dolphin-ctc-cxx-api.cc

@@ -7,7 +7,7 @@
 //
 // clang-format off
 //
-// wget https://github.com/k2-fsa/sherpa-onnx/releases/download/asr-models/sherpa-onnx-dolphin-base-ctc-multi-lang-int8-2025-04-02
+// wget https://github.com/k2-fsa/sherpa-onnx/releases/download/asr-models/sherpa-onnx-dolphin-base-ctc-multi-lang-int8-2025-04-02.tar.bz2
 // tar xvf sherpa-onnx-dolphin-base-ctc-multi-lang-int8-2025-04-02.tar.bz2
 // rm sherpa-onnx-dolphin-base-ctc-multi-lang-int8-2025-04-02.tar.bz2
 //

dotnet-examples/offline-decode-files/Program.cs

@@ -75,6 +75,9 @@ class OfflineDecodeFiles
     [Option("nemo-ctc", Required = false, HelpText = "Path to model.onnx. Used only for NeMo CTC models")]
     public string NeMoCtc { get; set; } = string.Empty;
 
+    [Option("dolphin-model", Required = false, Default = "", HelpText = "Path to dolphin ctc model")]
+    public string DolphinModel { get; set; } = string.Empty;
+
     [Option("telespeech-ctc", Required = false, HelpText = "Path to model.onnx. Used only for TeleSpeech CTC models")]
     public string TeleSpeechCtc { get; set; } = string.Empty;
 
@@ -233,6 +236,10 @@ to download pre-trained Tdnn models.
     {
       config.ModelConfig.NeMoCtc.Model = options.NeMoCtc;
     }
+    else if (!string.IsNullOrEmpty(options.DolphinModel))
+    {
+      config.ModelConfig.Dolphin.Model = options.DolphinModel;
+    }
     else if (!string.IsNullOrEmpty(options.TeleSpeechCtc))
     {
       config.ModelConfig.TeleSpeechCtc = options.TeleSpeechCtc;

dotnet-examples/offline-decode-files/run-dolphin-ctc.sh

@@ -0,0 +1,16 @@
+#!/usr/bin/env bash
+
+set -ex
+
+if [ ! -f ./sherpa-onnx-dolphin-base-ctc-multi-lang-int8-2025-04-02/model.int8.onnx ]; then
+  curl -SL -O https://github.com/k2-fsa/sherpa-onnx/releases/download/asr-models/sherpa-onnx-dolphin-base-ctc-multi-lang-int8-2025-04-02.tar.bz2
+  tar xvf sherpa-onnx-dolphin-base-ctc-multi-lang-int8-2025-04-02.tar.bz2
+  rm sherpa-onnx-dolphin-base-ctc-multi-lang-int8-2025-04-02.tar.bz2
+  ls -lh sherpa-onnx-dolphin-base-ctc-multi-lang-int8-2025-04-02
+fi
+
+dotnet run \
+  --tokens=./sherpa-onnx-dolphin-base-ctc-multi-lang-int8-2025-04-02/tokens.txt \
+  --dolphin-model=./sherpa-onnx-dolphin-base-ctc-multi-lang-int8-2025-04-02/model.int8.onnx \
+  --num-threads=1 \
+  --files ./sherpa-onnx-dolphin-base-ctc-multi-lang-int8-2025-04-02/test_wavs/0.wav

scripts/dotnet/OfflineDolphinModelConfig.cs

@@ -0,0 +1,17 @@
+/// Copyright (c)  2025  Xiaomi Corporation (authors: Fangjun Kuang)
+
+using System.Runtime.InteropServices;
+
+namespace SherpaOnnx
+{
+    [StructLayout(LayoutKind.Sequential)]
+    public struct OfflineDolphinModelConfig
+    {
+        public OfflineDolphinModelConfig()
+        {
+            Model = "";
+        }
+        [MarshalAs(UnmanagedType.LPStr)]
+        public string Model;
+    }
+}

scripts/dotnet/OfflineModelConfig.cs

@@ -26,6 +26,7 @@ namespace SherpaOnnx
             SenseVoice = new OfflineSenseVoiceModelConfig();
             Moonshine = new OfflineMoonshineModelConfig();
             FireRedAsr = new OfflineFireRedAsrModelConfig();
+            Dolphin = new OfflineDolphinModelConfig();
         }
         public OfflineTransducerModelConfig Transducer;
         public OfflineParaformerModelConfig Paraformer;
@@ -58,5 +59,6 @@ namespace SherpaOnnx
         public OfflineSenseVoiceModelConfig SenseVoice;
         public OfflineMoonshineModelConfig Moonshine;
         public OfflineFireRedAsrModelConfig FireRedAsr;
+        public OfflineDolphinModelConfig Dolphin;
     }
 }