a hardware-accelerated media viewer built with Rust

---

About

Bloom is a fast, lightweight media viewer with GPU-accelerated rendering and a wide range of supported formats, from everyday JPEGs to camera RAW, HDR, scientific formats, animation, and video. It also includes a set of light, non-destructive editing tools for quick adjustments. It is a viewer first and not a full editor, focused on doing the simple things well.

Features

• GPU rendering: hardware-accelerated via wgpu, with mipmaps and tiled textures for images beyond GPU limits
• Broad format support: dozens of image formats plus animation (GIF, APNG, WebP) and video (MP4, MOV, MKV, WebM, and more) with audio, scrubbing, and frame stepping
• Non-destructive modifiers: 26 stackable effects, from color correction (levels, exposure, vibrance, and more) to blur (Gaussian, motion), halftone, grain, pixel sort at any angle, and geometry (crop, resize, trim)
• Draw and text tools: paint freehand brush strokes and place text directly on the canvas
• Export: PNG, JPEG, or WebP with crop, rotation, and modifiers applied
• Gallery: browse every image in a folder, and open files by drag and drop or clipboard paste
• Info panel: dimensions, EXIF, RGB histogram, and pixel color under the cursor
• Themes: 22 built-in, including Catppuccin, Tokyo Night, Nord, and Gruvbox
• Customizable keybindings: rebind any action in preferences

Supported Formats

Format	Extension	Notes
Animated PNG	.apng	Animated
Apple Icon	.icns	Largest available size
BMP	.bmp
DDS	.dds	BC1–BC7 and uncompressed
DICOM	.dcm .dicom	Medical imaging, first frame
EPS / PostScript	.eps .ps .epsf	Requires Ghostscript on PATH
Farbfeld	.ff
FITS	.fits .fit .fts	Astronomy imaging; linear normalized to greyscale
GIF	.gif	Animated
GIMP	.xcf	Layers composited top-to-bottom
HDR (Radiance)	.hdr	Tonemapped (Reinhard)
HEIC / HEIF	.heic .heif	In default/-heif downloads; --features heif from source
ICO	.ico	Largest available size
JPEG	.jpg .jpeg
JPEG 2000	.jp2 .j2k .j2c .jpx
JPEG XL	.jxl
Krita	.kra	Merged composite, no layers
KTX2	.ktx2	Basis Universal and uncompressed
OpenEXR	.exr	Tonemapped (Reinhard)
Photoshop	.psd .psb	Merged composite, no layers
PNG	.png
Portable bitmap	.pbm .pgm .ppm
QOI	.qoi
RAW	.ari .arw .cr2 .cr3 .crm .crw .dcr .dcs .dng .erf .fff .iiq .kdc .mef .mos .mrw .nef .nrw .orf .ori .pef .qtk .raf .raw .rwl .rw2 .srw .x3f .3fr	Camera RAW; not all models supported
SVG	.svg .svgz	Rasterized at native size
TGA	.tga
TIFF	.tif .tiff	No 64-bit float
Video	.mp4 .m4v .mov .mkv .webm .avi .mpg .mpeg .ts .m2ts .wmv .flv	Playback with audio; in the default download or --features av from source
WebP	.webp	Static and animated

Download

Prebuilt releases come in three flavors per platform. Pick based on which formats you need:

Download	Includes	Size
bloom-<platform>	Everything, including HEIC/HEIF and video	Largest
bloom-<platform>-heif	Core formats + HEIC/HEIF, no video	Smaller
bloom-<platform>-minimal	Core formats only	Smallest

Video is the bulk of the size (it bundles FFmpeg), so grab -heif or -minimal if you don't need it.

Builds are published for Windows x86_64, Linux x86_64 and Apple Silicon macOS. Intel Macs are not covered yet, so those need a build from source.

Build

The feature flags below only matter when building from source. Prebuilt downloads above already include them.

cargo build --release

For HEIC/HEIF support, the libheif-rs bindings link against libheif. A helper script sets it up:

# macOS / Linux
./scripts/setup-heif.sh

# Windows (PowerShell): builds libheif via vcpkg into vendor/ and sets VCPKG_ROOT
./scripts/setup-heif.ps1

cargo build --release --features heif

On macOS the script installs libheif with Homebrew. On Linux it checks for libheif and tells you the package to install if it is missing:

sudo apt install libheif-dev   # Ubuntu/Debian
sudo dnf install libheif-devel # Fedora
sudo pacman -S libheif         # Arch

On Windows it clones vcpkg into vendor/vcpkg, builds libheif from source, and sets a persistent VCPKG_ROOT. Open a new terminal afterward so the environment changes take effect.

For video playback, the ffmpeg-next bindings link against FFmpeg. A helper script sets it up:

# macOS / Linux
./scripts/setup-av.sh

# Windows (PowerShell): downloads a prebuilt FFmpeg into vendor/ and sets FFMPEG_DIR
./scripts/setup-av.ps1

cargo build --release --features av

On macOS the script installs FFmpeg with Homebrew. On Linux it checks for the FFmpeg dev libraries and tells you the package to install if they are missing:

sudo apt install libavformat-dev libavfilter-dev libavdevice-dev libclang-dev   # Ubuntu/Debian
sudo dnf install ffmpeg-devel clang                                            # Fedora
sudo pacman -S ffmpeg clang                                                    # Arch

On Windows it fetches a prebuilt FFmpeg into vendor/ffmpeg and installs LLVM. Open a new terminal afterward so the environment changes take effect.

Requires a GPU with WebGPU support. On Windows, DX12 is used by default.

Privacy

Bloom is entirely local. No telemetry, no analytics, no network requests — ever. Your files stay on your machine.