trv

Transform slides and speaker notes into video.

Installation

cargo install trv

Or with cargo binstall:

cargo binstall trv

Usage

Create a Typst presentation with speaker notes:

#import "@preview/polylux:0.4.0": *

#set page(paper: "presentation-16-9")

#set text(size: 25pt)

#slide[
    #toolbox.pdfpc.speaker-note(
    ```md
    What if you could show code in a video?
    ```
    )

    \
    #align(center)[Code examples or code videos?]
]

To create a video from the presentation with DeepInfra, run:

$ export DEEPINFRA_KEY="<YOUR KEY>"

$ trv --input=presentation.typ
 INFO Generating audio file for slide 0
 INFO Generating audio file for slide 1
 INFO Creating video clip _out/1.mp4
 INFO Created video clip _out/1.mp4
 INFO Creating video clip _out/2.mp4
 INFO Created video clip _out/2.mp4
 INFO Concatenated video clips into _out/out.mp4

Now, the presentation is available as _out/out.mp4.

To create a video without an API key nor an internet connection, you can self-host Kokoros. See the Kokoros section for more information.

A simple alternative is to use the hosted version at https://kokoros.transformrs.org. For example, this command creates a video using the hosted service:

$ trv --input=presentation.typ \
    --provider=openai-compatible(kokoros.transformrs.org) \
    --model=tts-1 \
    --voice=bm_lewis \
    --audio-format=wav \
    --release

Kokoros

To use Kokoros locally, the easiest way is to use the Docker image.

$ git clone https://github.com/lucasjinreal/Kokoros.git

$ cd Kokoros/

$ docker build --rm -t kokoros .

$ docker run -it --rm -p 3000:3000 kokoros openai

Then, you can use the Docker image as the provider:

$ trv --input=presentation.typ --provider=openai-compatible(localhost:3000)

Compatibility

The output video is not compatible with all video players. To make it more compatible, you can use ffmpeg. For example, this script converts the video to a more compatible format with aac audio.

#!/usr/bin/env bash

set -e

# Convert video to highly-compatible format with aac audio.
# Using the advanced aac encoder via fdk-aac (unix) or aac_at (apple).

ffmpeg \
    -y \
    -i _out/out.mp4 \
    -c:v libx264 -crf 23 -preset fast \
    -vf "scale=-1:1080,format=yuv420p" \
    -c:a aac_at \
    -strict experimental \
    _out/out-aac.mp4

About Audio

Audio is generated using the transformrs crate. It supports multiple providers, including DeepInfra, OpenAI, and Google.

So trv should also work with providers other than DeepInfra. However, during testing, I got the best results with DeepInfra for the lowest price.

For example, OpenAI text-to-speech requires any video to contain a "clear disclosure" that the voice they are hearing is AI-generated.

Google, meanwhile, has the best text-to-speech engine that I've found as part of Gemini 2.0 Flash Experimental. However, audio output is not yet available via the API.