MV Render Render music videos with waveform visualization and synced lyrics from audio + lyrics input. Prerequisites Remotion project at scripts/ directory within this skill Node.js + npm dependencies installed ffprobe available (for audio duration detection) First-Time Setup Before first use, check and install dependencies:

1. Check Node.js

node --version

2. Install npm dependencies

cd { project_root } / { .claude or .codex } /skills/acestep-simplemv/scripts && npm install

3. Check ffprobe

ffprobe
-version
If ffprobe is not available, install ffmpeg (which includes ffprobe):
Windows
:
choco install ffmpeg
or download from
https://ffmpeg.org/download.html
and add to PATH
macOS
:
brew install ffmpeg
Linux
:
sudo apt-get install ffmpeg
(Debian/Ubuntu) or
sudo dnf install ffmpeg
(Fedora)
Quick Start
cd
{
project_root
}
/
{
.claude or .codex
}
/skills/acestep-simplemv/
./scripts/render-mv.sh
--audio
/path/to/song.mp3
--lyrics
/path/to/song.lrc
--title
"Song Title"
Output: MP4 file at
out/.mp4
(or custom
--output
path).
Script Usage
./scripts/render-mv.sh
--audio
<
file
>
--lyrics
<
lrc_file
>
--title
"Title"
[
options
]
Options:
--audio
Audio
file
path
(
absolute paths supported
)
--lyrics
LRC
format
lyrics
file
(
timestamped
)
--lyrics-json JSON lyrics
file
[
{
start, end, text
}
]
(
alternative to --lyrics
)
--title
Video title
(
default:
"Music Video"
)
--subtitle
Subtitle text
--credit
Bottom credit text
--offset
Lyric timing offset
in
seconds
(
default: -0.5
)
--output
Output
file
path
(
default: out/
<
audio_basename
>
.mp4
)
--codec
h264
|
h265
|
vp8
|
vp9
(
default: h264
)
--browser
Custom browser executable path
(
Chrome/Edge/Chromium
)
Environment variables:
BROWSER_EXECUTABLE Path to browser executable
(
overrides auto-detection
)
Browser Detection
Remotion requires a Chromium-based browser for rendering. The script auto-detects browsers in this priority order:
BROWSER_EXECUTABLE
environment variable
--browser
CLI argument
Remotion cache (
chrome-headless-shell
, downloaded by Remotion)
System Chrome (auto-uses
--chrome-mode=chrome-for-testing
)
System Edge
(pre-installed on Windows 10/11, auto-uses
--chrome-mode=chrome-for-testing
)
System Chromium (auto-uses
--chrome-mode=chrome-for-testing
)
Important: New versions of Chrome/Edge removed the old headless mode. When using regular Chrome/Edge/Chromium, the script automatically sets --chrome-mode=chrome-for-testing (which uses --headless=new ). When using chrome-headless-shell , it uses the default headless-shell mode (which uses --headless=old ). This is handled transparently. If no browser is found, Remotion will attempt to download chrome-headless-shell from Google servers. This will fail if Google servers are inaccessible from your network. Workarounds for restricted networks Since Edge is pre-installed on Windows 10/11 , it should be auto-detected without any manual configuration. The script automatically detects Chrome/Edge and uses the correct headless mode. If auto-detection fails:

Option 1: Set environment variable

export BROWSER_EXECUTABLE = "/path/to/msedge.exe"

Option 2: Pass as CLI argument

./scripts/render-mv.sh --audio song.mp3 --lyrics song.lrc --title "Song" --browser "/path/to/msedge.exe"

Option 3: Enable proxy and let Remotion download chrome-headless-shell

Examples

Basic render

./scripts/render-mv.sh --audio /tmp/abc123_1.mp3 --lyrics /tmp/abc123.lrc --title "夜桜"

Custom output path

./scripts/render-mv.sh --audio song.mp3 --lyrics song.lrc --title "My Song" --output /tmp/my_mv.mp4

With subtitle and credit

./scripts/render-mv.sh
--audio
song.mp3
--lyrics
song.lrc
--title
"Song"
--subtitle
"Artist Name"
--credit
"Generated by ACE-Step"
File Naming
IMPORTANT: Use the audio file's job ID as the output filename to avoid overwriting. Do NOT use custom names like --output my_song.mp4 . Let the default naming handle it (derives from audio filename). Default output uses the audio filename as base: Audio: acestep_output/{job_id}_1.mp3 Lyrics: acestep_output/{job_id}_1.lrc Video: Pass --output acestep_output/{job_id}.mp4 (use the job ID from the audio file) Example: if audio is chatcmpl-abc123_1.mp3 , pass --output acestep_output/chatcmpl-abc123.mp4 Title Guidelines Keep --title short and single-line (max ~50 chars, auto-truncated) Use --subtitle for additional info Do NOT put newlines in --title Good: --title "Open Source" --subtitle "ACE-Step v1.5" Bad: --title "Open Source - ACE-Step v1.5\nCelebrating Music AI" Notes Audio files with absolute paths are auto-copied to public/ by render.mjs Duration is auto-detected via ffprobe Typical render time: ~1-2 minutes for a 90s song Output resolution: 1920x1080, 30fps

安装