Update how-to-lower-speech-synthesis-latency.md

Author: sally-baolian

articles/ai-services/speech-service/how-to-lower-speech-synthesis-latency.md

@@ -318,6 +318,42 @@ For Linux and Windows, `GStreamer` is required to enable this feature.
 Refer [this instruction](how-to-use-codec-compressed-audio-input-streams.md) to install and configure `GStreamer` for Speech SDK.
 For Android, iOS and macOS, no extra configuration is needed starting version 1.20.
 
+## Text stream
+
+The text stream API allows real-time text processing for rapid audio generation. It's perfect for dynamic text vocalization, such as reading outputs from AI models like GPT in real-time. This API minimizes latency and improves the fluidity and responsiveness of audio outputs, making it ideal for interactive applications, live events, and responsive AI-driven dialogues.
+
+### How to use the text stream API
+
+To use the text stream API, connect to the websocket V2 endpoint: `wss://{region}.tts.speech.microsoft.com/cognitiveservices/websocket/v2`
+
+::: zone pivot="programming-language-csharp"
+
+#### Key steps
+
+1. **Create a text stream request**: Use `SpeechSynthesisRequestInputType.TextStream` to initiate a text stream.
+1. **Set global properties**: Adjust settings such as output format and voice name directly, as the API handles partial text inputs and doesn't support SSML. Refer to the following sample code for instructions on how to set them.
+
+    ```csharp
+    // Set output format
+    speechConfig.SetSpeechSynthesisOutputFormat(SpeechSynthesisOutputFormat.Raw24Khz16BitMonoPcm);
+
+    // Set a voice name
+    SpeechConfig.SetProperty(PropertyId.SpeechServiceConnection_SynthVoice, "en-US-AvaMultilingualNeural");
+    ```
+   
+1. **Stream your text**: For each text chunk generated from a GPT model, use `request.InputStream.Write(text);` to send the text to the stream.
+1. **Close the stream**: Once the GPT model completes its output, close the stream using `request.InputStream.Close();`.
+
+For detailed implementation, see the [sample code on GitHub](https://github.com/Azure-Samples/cognitive-services-speech-sdk/tree/master/samples/csharp/tts-text-stream)
+
+::: zone-end
+
+::: zone pivot="programming-language-python"
+
+
+
+::: zone-end
+
 ## Others tips
 
 ### Cache CRL files