The initial node, GM Image JPEG Save, is an output-only JPEG saver. It saves ComfyUI IMAGE tensors directly as JPEG using GraphicsMagick, without creating intermediate PNG files and without returning preview images.

Node

GM Image JPEG Save

A deliberately narrow JPEG saver node.

It does not try to be a general image saver.

JPEG only
No PNG output
No preview output
No IMAGE passthrough
No frontend/localStorage dependency
No HandpickerSuite dependency
Optional JPEG comment via input pin only
Optional label input pin for filename/directory naming
Image-by-image progress bar updates

For PNG output, use ComfyUI's standard Save Image node.

Requirements

GraphicsMagick is required.

Download GraphicsMagick from the official site:

GM Image JPEG Save resolves GraphicsMagick in this order:

GM_PATH environment variable
gm from PATH

If GraphicsMagick is available in PATH, no setting is needed.

Timeout

GraphicsMagick is given a per-image timeout. The default is 300 seconds.

To change it, set this environment variable before starting ComfyUI:

GM_IMAGE_SAVER_TIMEOUT=300

Windows

Install GraphicsMagick and enable the option to update PATH if available. After installing, restart ComfyUI so the updated PATH is visible.

If PATH is not available, set the GM_PATH environment variable to the full path of gm.exe, for example:

C:\Program Files\GraphicsMagick-1.3.45-Q16\gm.exe

Linux

Install GraphicsMagick using your distribution package manager and make sure gm is available in PATH.

For example, on Debian / Ubuntu:

sudo apt install graphicsmagick

Inputs

Required:

images: ComfyUI IMAGE
filename_prefix: filename prefix. Default image.
directory_pattern: directory layout pattern. Default prefix/date.
filename_date_format: optional date text in the filename. Default none.
quality: JPEG quality, default 95
subsampling: JPEG chroma subsampling, default 4:4:4
progressive: progressive JPEG, default False

Optional input pins:

output_dir: base output directory. Connect from a string/text node.
label: optional extra naming string. You can connect ckpt_name_safe or any other label string.
comment: JPEG comment string. Connect from a string/text node.

If output_dir is unconnected or empty, ComfyUI's standard output directory is used.

If output_dir is a relative path, it is resolved under ComfyUI's standard output directory.

If output_dir is an absolute path, it is used as-is.

Generated directory/file components are sanitized. Hyphens are intentionally converted to underscores.

Directory patterns

directory_pattern controls folders under output_dir.

The date part is always yyyyMMdd.

Available patterns:

none
date
prefix
prefix_date
prefix/date
label
label_date
label/date
prefix_label
prefix/label
prefix_label_date
prefix/label/date
prefix_date_label
prefix/date/label

Example values:

output_dir: D:\ComfyJPEG
filename_prefix: image
label: meinamix_v11
date: 20260601

Results:

none                -> D:\ComfyJPEG
date                -> D:\ComfyJPEG\20260601
prefix              -> D:\ComfyJPEG\image
prefix_date         -> D:\ComfyJPEG\image_20260601
prefix/date         -> D:\ComfyJPEG\image\20260601
label               -> D:\ComfyJPEG\meinamix_v11
label_date          -> D:\ComfyJPEG\meinamix_v11_20260601
label/date          -> D:\ComfyJPEG\meinamix_v11\20260601
prefix_label        -> D:\ComfyJPEG\image_meinamix_v11
prefix/label        -> D:\ComfyJPEG\image\meinamix_v11
prefix_label_date   -> D:\ComfyJPEG\image_meinamix_v11_20260601
prefix/label/date   -> D:\ComfyJPEG\image\meinamix_v11\20260601
prefix_date_label   -> D:\ComfyJPEG\image_20260601_meinamix_v11
prefix/date/label   -> D:\ComfyJPEG\image\20260601\meinamix_v11

Patterns containing label require a label input.

Naming compatibility

Generated path parts are sanitized for filesystem safety, but hyphens are preserved.

This keeps the label input compatible with tools such as HandpickerSuite's ckpt_name_safe, where names like foo-model-v1 are expected to remain unchanged.

Filename date formats

filename_date_format controls date text in the filename, not the directory.

Available values:

none
yyyyMMdd
yyyyMMdd_HHmm

The counter is four digits.

Examples:

image_0001.jpg
image_20260601_0001.jpg
image_20260601_1423_0001.jpg
image_meinamix_v11_0001.jpg
image_meinamix_v11_20260601_1423_0001.jpg

If label is connected, it is included in the filename automatically.

The timestamp is fixed once per node execution, so images in the same batch use the same timestamp.

Progress

The node updates ComfyUI's progress bar once per successfully saved image.

Preview policy

This node intentionally does not return preview images.

For previews, branch the IMAGE before this node and connect it to your preferred preview node.

Example:

VAE Decode / IMAGE
  ├─ Preview node
  └─ GM Image JPEG Save

Project scope

This repository is named GMImageSaver so that additional GraphicsMagick-based saver nodes can be added in the future.

However, the initial node is intentionally narrow:

JPEG only
no preview
no PNG support
no automatic metadata injection
no external project coupling

License

MIT