# ComfyUI-VoiceBridge

VoiceBridge

VoiceBridge translates spoken audio from any language to a target language while preserving the original speaker's voice characteristics, and generates bilingual SRT subtitle files.

## 🔄 Workflow This node integrates ASR (Automatic Speech Recognition), LLM (Large Language Model), and TTS (Text-to-Speech) technologies to provide a complete speech translation pipeline. [Online Workflow](https://www.runninghub.ai/post/2050059053363154946?inviteCode=rh-v1455) ### ASR + LLM + TTS Workflow ![](./assets/workflow.png) ### Universal TTS Workflow ![](./assets/universal-tts.png) ## ✨ Features - 🌍 **Speech Translation:** Convert speech from one language to any other language while retaining the original speaker's voice timbre. - 🗣️ **Multi-Language Support:** Speech recognition and translation in dozens of languages covering all major global languages. - ⏱️ **Automatic Voice Alignment:** The generated translated voice is automatically aligned with the original voice to stay in sync with the video content. - 📝 **Accurate Subtitle Generation:** Through force-align technology, VoiceBridge produces accurate subtitles synchronized with the voice at the millisecond level. - 🔌 **Universal TTS Support:** The new decoupled pipeline — `Load SRT` → `SRT Splitter` → `` → `Audio List Merger by SRT` — lets you drive **any ComfyUI TTS custom node** (Qwen3-TTS, VoxCPM, Fish Audio S2, LongCat-AudioDiT, CosyVoice, …). As long as the TTS node takes a `STRING` and returns an `AUDIO`. ## 📦 Installation ### Via ComfyUI Manager (Recommended) Search for "VoiceBridge" in ComfyUI Manager ### Manual Installation ```bash cd ComfyUI/custom_nodes git clone https://github.com/YanTianlong-01/comfyui_voicebridge.git cd comfyui_voicebridge pip install -r requirements.txt ``` ### Model Directory Structure VoiceBridge automatically searches or download models in the following priority: ```text ComfyUI/ ├── models/ │ └── Qwen3-TTS/ │ | ├── Qwen3-TTS-12Hz-1.7B-Base/ │ | ├── Qwen3-TTS-12Hz-0.6B-Base/ │ └── Qwen3-ASR/ │ ├── Qwen3-ASR-1.7B/ │ ├── Qwen3-ASR-0.6B/ │ ├── Qwen3-ForcedAligner-0.6B/ ``` or you can use the local model path. Setting `local_model_path`=`qwen-tts/Qwen3-TTS-12Hz-1.7B-Base` means use the model in `ComfyUI/models/qwen-tts/Qwen3-TTS-12Hz-1.7B-Base`. For ASR models, you can set `local_model_path_asr`=`qwen-asr/Qwen3-ASR-1.7B`. For ForcedAligner models, you can set `local_model_path_fa`=`qwen-asr/Qwen3-ForcedAligner-0.6B`. ## 🧩 Nodes ### 📥 Load SRT Loads an `.srt` (or `.txt`) subtitle file from `ComfyUI/input/`. The node ships with a dropdown listing existing files, plus a frontend-injected **"choose srt file to upload"** button that mirrors the UX of ComfyUI's built-in *Load Audio* node. Uploaded files are saved to the input directory and appear in the dropdown immediately. Output is the raw SRT string, ready to be wired into `SRT Splitter.srt_string`. | Input | Type | Description | |-------|------|-------------| | srt | dropdown | Pick an `.srt` / `.txt` file from `ComfyUI/input/`. Uploaded files are auto-added to this list. | | **Output** | **Type** | **Description** | | srt_string | STRING | Raw SRT content decoded from the file (UTF-8 with BOM / GBK fallback handled internally). | --- ### ✂️ SRT Splitter Parses an SRT string and splits it into a list of per-sentence texts plus a metadata object that carries the original timestamps. Because `texts` is emitted as a native ComfyUI `LIST`, any downstream TTS node connected to it will be executed once per sentence automatically — no custom loop nodes required. | Input | Type | Description | |-------|------|-------------| | srt_string | STRING | SRT text from `Load SRT`, `Generate SRT`, or a manual paste. | | **Output** | **Type** | **Description** | | texts | LIST[STRING] | List of per-sentence texts, one entry per SRT subtitle. ComfyUI's list-iteration will feed them to the downstream TTS one by one. | | srt_items | VB_SRT_ITEMS | Metadata object holding `(index, start_ms, end_ms, text)` for every subtitle entry. Feed this into `Audio List Merger by SRT`. | | count | INT | Number of subtitle entries parsed. | --- ### 🔀 Audio List Merger by SRT Collects the per-sentence `AUDIO` outputs produced by any external TTS node (iterated over `SRT Splitter.texts`) and merges them back into a single `AUDIO` aligned with the original SRT timestamps. Uses the same duration-matching / tempo-limit / cascading-shift algorithm as the legacy `SRT To Audio` node. The sample rate is read from the first incoming `AUDIO` dict and every other sentence is resampled to match. | Input | Type | Description | |-------|------|-------------| | srt_items | VB_SRT_ITEMS | Metadata from `SRT Splitter` carrying the original timestamps. | | audios | LIST[AUDIO] | Per-sentence AUDIO outputs from any TTS node — auto-collected by ComfyUI's list-iteration. | | tempo_limit | FLOAT | (optional) Maximum speed-up factor for audio that overflows a subtitle slot. Default 1.5, range 1.0–5.0. | | mini_gap_ms | INT | (optional) Minimum gap between consecutive subtitles in milliseconds. Default 100, range 0–10,000. | | **Output** | **Type** | **Description** | | audio | AUDIO | Final merged audio in ComfyUI format (`waveform`, `sample_rate`). | | adjusted_srt | STRING | Adjusted SRT string whose timing reflects the real audio durations after tempo / shift corrections. | --- ### VoiceBridge ASR Loader Loads the Qwen3-ASR model with auto-download support. This node manages model loading with intelligent caching and supports both HuggingFace and ModelScope model sources. | Input | Type | Description | |-------|------|-------------| | repo_id | dropdown | Model repository selection (Qwen/Qwen3-ASR-1.7B or Qwen/Qwen3-ASR-0.6B) | | source | dropdown | Model download source: HuggingFace or ModelScope | | precision | dropdown | Computation precision: fp16, bf16, or fp32 | | attention | dropdown | Attention implementation: auto, flash_attention_2, sdpa, or eager | | max_new_tokens | INT | Maximum tokens to generate during transcription (default: 256, range: 1-4096) | | forced_aligner | dropdown | Optional forced aligner model for word-level timestamps (None or Qwen/Qwen3-ForcedAligner-0.6B) | | local_model_path_asr | STRING | Optional custom local path for ASR model loading | | local_model_path_fa | STRING | Optional custom local path for forced aligner model loading | | **Output** | **Type** | **Description** | | model | QWEN3_ASR_MODEL | Loaded ASR model instance for transcription operations | --- ### VoiceBridge ASR Transcribe Transcribes a single audio input to text using the loaded Qwen3-ASR model. Supports automatic language detection and optional timestamp generation for precise word-level timing. | Input | Type | Description | |-------|------|-------------| | model | QWEN3_ASR_MODEL | Pre-loaded ASR model from VoiceBridge ASR Loader | | audio | AUDIO | Audio input in ComfyUI format (waveform and sample_rate) | | language | dropdown | Target language for transcription or "auto" for automatic detection | | context | STRING | Optional context hints to improve transcription accuracy for specialized content | | return_timestamps | BOOLEAN | Enable word-level timestamp output for precise timing information | | **Output** | **Type** | **Description** | | forced_aligns | LIST | List of ForcedAlignItem objects containing word-level timing data (if timestamps enabled) | | text | STRING | Transcribed text content from the audio input | | language | STRING | Detected or specified language code | | timestamps | STRING | Formatted string with word-level timestamps in "start_time-end_time: word" format (if enabled) | --- ### Generate SRT Generates an SRT subtitle file from transcribed text and forced alignment timestamps. This node combines text segmentation with timestamp data to create properly timed subtitle entries. | Input | Type | Description | |-------|------|-------------| | forced_aligns | LIST | List of ForcedAlignItem objects with word-level timestamps from ASR transcription | | text | STRING | Input text content to convert to SRT format | | language | STRING | Language of SRT text | | save_srt | BOOLEAN | Enable automatic saving of the generated SRT file to output directory (default: True) | | file_name | STRING | Base file name for the SRT output (default: "VoiceBridge\subtitle") | | **Output** | **Type** | **Description** | | srt_string | STRING | Generated SRT formatted string with proper timestamps and segmentation | --- ### VoiceBridge AI API Provides integration with OpenAI-compatible API endpoints for AI-powered text processing. Supports customizable system prompts and generation parameters for flexible content generation workflows. | Input | Type | Description | |-------|------|-------------| | model | STRING | API model identifier to use for text generation | | base_url | STRING | Base URL endpoint for the API (must be OpenAI-compatible) | | api_key | STRING | API authentication key for the service | | system_prompt | STRING | System instruction defining the AI assistant's behavior and constraints | | prompt | STRING | User prompt or query to send to the API | | max_tokens | INT | Maximum number of tokens in the generated response (default: 4096, range: 1-1000000) | | temperature | FLOAT | Sampling temperature controlling randomness (default: 0.7, range: 0-1) | | top_p | FLOAT | Nucleus sampling threshold for token selection (default: 0.95, range: 0-1) | | **Output** | **Type** | **Description** | | response | STRING | Generated text response from the API | --- ### VoiceBridge TTS Loader Loads the Qwen3-TTS text-to-speech model with auto-download support. This node handles model caching and supports multiple model variants for different voice synthesis needs. | Input | Type | Description | |-------|------|-------------| | repo_id | dropdown | Model repository selection (Qwen/Qwen3-TTS-12Hz-1.7B-Base or Qwen/Qwen3-TTS-12Hz-0.6B-Base) | | source | dropdown | Model download source: HuggingFace or ModelScope | | precision | dropdown | Computation precision: fp16, bf16, or fp32 | | attention | dropdown | Attention implementation: auto, flash_attention_2, sdpa, or eager | | local_model_path | STRING | Optional custom local path for TTS model loading | | **Output** | **Type** | **Description** | | model | QWEN3_TTS_MODEL | Loaded TTS model instance for voice synthesis operations | --- ### Voice Clone Prompt Creates a voice clone prompt from reference audio for use with the Qwen3-TTS model. This enables voice cloning by extracting voice characteristics from a sample audio file. | Input | Type | Description | |-------|------|-------------| | model | QWEN3_TTS_MODEL | Pre-loaded TTS model from VoiceBridge TTS Loader | | ref_audio | AUDIO | Reference audio sample for voice cloning (ComfyUI Audio format) | | ref_text | STRING | Transcript of the reference audio content (highly recommended for better quality) | | **Output** | **Type** | **Description** | | voice_clone_prompt | VOICE_CLONE_PROMPT | Voice clone prompt object containing extracted voice characteristics for TTS generation | --- ### SRT To Audio Converts SRT subtitle content to audio using the Qwen3-TTS model with voice cloning. Includes intelligent duration matching to align generated audio with subtitle timing, with optional speed adjustment for timing mismatches. | Input | Type | Description | |-------|------|-------------| | model | QWEN3_TTS_MODEL | Pre-loaded TTS model from VoiceBridge TTS Loader | | srt_string | STRING | SRT formatted subtitle text to convert to audio | | voice_clone_prompt | VOICE_CLONE_PROMPT | Voice clone prompt from Voice Clone Prompt node | | language | dropdown | Target language for synthesis or "auto" for automatic detection | | tempo_limit | FLOAT | Maximum speed-up factor for audio that exceeds subtitle duration (default: 1.5, range: 1.0-5.0) | | mini_gap_ms | INT | Minimum gap between consecutive subtitles in milliseconds (default: 100, range: 0-10,000) | | batch_size | INT | Number of subtitle entries to process in each batch (default: 10, range: 1-1,000) | | **Output** | **Type** | **Description** | | audio | AUDIO | Generated audio in ComfyUI format (waveform and sample_rate) | | adjusted_srt | STRING | Adjusted SRT string with corrected timing based on actual audio durations | --- ### Save SRT From String Saves an SRT formatted string to a file in the ComfyUI output directory. Automatically handles file naming conflicts by appending incrementing indices. | Input | Type | Description | |-------|------|-------------| | srt_string | STRING | SRT formatted string content to save | | file_name | STRING | Base file name for the SRT output (default: "VoiceBridge\subtitle") | | **Output** | **Type** | **Description** | | save_path | STRING | Full path where the SRT file was saved | --- ### 🧹 VoiceBridge Unload Model Unloads cached ASR and/or TTS models from GPU memory to free VRAM. Useful when chaining different models sequentially or running on limited-memory GPUs. Acts as a pass-through node — wire the `anything` input after the node whose output you want to keep, and the same value will be forwarded on `any` once the unload runs. | Input | Type | Description | |-------|------|-------------| | anything | * | Any value, passed straight through the node so you can insert it anywhere in a chain. | | Unload_ASR_Model | BOOLEAN | Unload the ASR model cache (default `True`). | | Unload_TTS_Model | BOOLEAN | Unload the TTS model cache (default `True`). | | **Output** | **Type** | **Description** | | any | * | Same value as `anything` (pass-through). | ## 🙏 Acknowledgments - [Qwen3-ASR](https://github.com/QwenLM/Qwen3-ASR) and [Qwen3-TTS](https://github.com/QwenLM/Qwen3-TTS): Official open-source repository by Alibaba Qwen team. - [ComfyUI-Qwen3-ASR](https://github.com/DarioFT/ComfyUI-Qwen3-ASR): A nice and clean ComfyUI node by DarioFT. ## 📄 License This project is licensed under the MIT License - see the [LICENSE](./LICENSE) file for details.

Name	Type	Default	Description
srt_string	STRING		—
filename_prefix	STRING	VoiceBridge_subtitle	—

Save SRT From String

Inputs (2)

Outputs (1)