Gocast Voice Service

Microservice that generates subtitles for TUM-Live. Using whisperX

Workflow

                     ┌──────────┐
      ┌──────────────┤  WORKER  │
      │              └──────────┘
      │
      │
      │ 1) .NotifyUploadFinished
      │
      │
      │
      │
┌─────▼──────┐       2) .Generate         ┌───────────┐
│            ├────────────────────────────►           │
│            │                            │   VOICE   │
│  TUM-LIVE  │                            │  SERVICE  │
│            │                            │           │
├────────────◄────────────────────────────┼───────────┤
│  RECEIVER  │        3) .Receive         │ GENERATOR │
└────────────┘                            └───────────┘

API

$ grpcurl -plaintext localhost:50055 list live.voice.v1.SubtitleGenerator

live.voice.v1.SubtitleGenerator.Generate

$ grpcurl -plaintext \
  -d '{"stream_id":1, "source_file":"/tmp/120.mp4"}' \
  -import-path ./protobufs -proto subtitles.proto \
  localhost:50055 live.voice.v1.SubtitleGenerator.Generate

Configuration

The service can be configured using the following command-line flags:

Flag	Description	Default
-parallelism	Number of concurrent jobs	3
-hw-accel	Enable hardware acceleration	true
-queue-size	Size of the job queue	10
-target	gocast server to push subtitles to	localhost:50053

Running with Docker

The voice-service interacts with the Docker daemon to manage its operations. Therefore, when running the service in a Docker container, you need to mount the Docker socket.

1. Build the Docker image:

   docker build -t gocast-voice-service .

2. Run the Docker container:

   You need to mount the Docker socket (/var/run/docker.sock) and map the gRPC port (50053).

   docker run -d \
     -p 50053:50053 \
     -v /var/run/docker.sock:/var/run/docker.sock \
     gocast-voice-service [flags]

   Replace [flags] with any desired command-line flags for the voice-service (e.g., -parallelism 4 -target some-host:50053).

   Example:

   docker run -d \
     -p 50053:50053 \
     -v /var/run/docker.sock:/var/run/docker.sock \
     gocast-voice-service -parallelism 4 -target my-gocast-server:50053

Batch tool

cmd/batch contains a tool that triggers subtitle generation for an entire gocast course:

go run cmd/batch/main.go --admintoken=secret '--dsn=user:password@tcp(localhost:3006)/db' --srv=localhost:50051 --lang=en --course=123

The admintoken can be configured in the gocast edge server config.