Multiple source images
Only one image is decoded; a concatenated image sequence is not exported as a complete set.
Convert PGM to JPEG XL
- In your browser
- No upload
- Private by design
What happens when you convert PGM to JPEG XL?
No new colour information
The source stores grayscale or bitonal values. A colour-capable JPEG XL can represent these tones, but conversion cannot infer original scene colours or recover missing intermediate shades. Colourisation would be a separate image-editing operation.
Transparency
The target can store an alpha channel, but converting an opaque image does not create transparent areas. Removing a background is a separate editing step.
Encoding mode
Lossless pixels, lossy pixels and reversible recompression of an eligible JPEG bitstream are separate modes. Exact JPEG reconstruction requires its reconstruction data, not just matching rendered pixels. Quality defaults to 80; adjust it in Advanced options. File size depends on the image and encoder.
PGM
Source
PGM
Portable Graymap
Compression: UncompressedTransparency: NoMetadata: Header, Comments
Portable Graymap: simple uncompressed raster samples for image-processing pipelines.
Explore PGM format →JPEG XL
Target
JPEG XL
JPEG XL Image Coding System
Compression: Lossy & losslessTransparency: YesMetadata: Exif, XMP, ICC, JUMBF
A JPEG-family image system for lossy and lossless pictures, high precision, alpha and animation.
Explore JPEG XL format →Is PGM → JPEG XL right for you?
Good choice when
- JPEG XL fits your delivery use: High-precision photographic storage.
- You can choose the source image or part needed for delivery.
- You need the existing gray or binary image in a compatible delivery format.
- Your receiving application supports the required JPEG XL variant.
- You need a JPEG XL-compatible workflow that can hold transparency added in a separate edit.
Probably not when
- You require a complete collection, page set or multipart round trip.
- You expect automatic colourisation or reconstruction of absent tones.
- You need a guaranteed output file size or archival pixel equality. Encoder settings do not guarantee either.
- You require identical samples without a defined colour and precision policy.
- You expect automatic background removal or transparency.
PGM to JPEG XL conversion details
- Multiple source images
- Only one image is decoded; a concatenated image sequence is not exported as a complete set.
- No new colour information
- The source stores grayscale or bitonal values. A colour-capable JPEG XL can represent these tones, but conversion cannot infer original scene colours or recover missing intermediate shades. Colourisation would be a separate image-editing operation.
- Transparency
- The target can store an alpha channel, but converting an opaque image does not create transparent areas. Removing a background is a separate editing step.
- Encoding mode
- Lossless pixels, lossy pixels and reversible recompression of an eligible JPEG bitstream are separate modes. Exact JPEG reconstruction requires its reconstruction data, not just matching rendered pixels. Quality defaults to 80; adjust it in Advanced options. File size depends on the image and encoder.
- Sample precision & colour
- Pixel conversion only. Original EXIF, GPS, XMP and ICC profiles are not copied; processing uses 8-bit display pixels.
- Metadata & colour
- Pixel conversion only. Original EXIF, GPS, XMP and ICC profiles are not copied; processing uses 8-bit display pixels.
- Compression
- PGM: Uncompressed → JPEG XL: Lossy & lossless PGM: Netpbm stores these samples without compression. Reducing colour, thresholding or changing maxval can still lose information before storage; text and binary representations change the layout, not its image meaning. JPEG XL: Lossless pixels, lossy pixels and reversible recompression of an eligible JPEG bitstream are separate modes. Exact JPEG reconstruction requires its reconstruction data, not just matching rendered pixels.
- Transparency
- Transparency is replaced with white by default. Change the background in Advanced options.
- Animation
- Still image output. Animated files use only the first frame; animation is not preserved.
- Colour depth
- PGM: maxval up to 65535 → JPEG XL: High-bit-depth samples
- HDR
- JPEG XL: Supported
- Layers
- JPEG XL: Frame blending; not PSD editing
- Dimensions
- Rendered image dimensions are retained within the converter limits; this tool does not offer resizing. Orientation handling depends on the source decoder.
- Metadata
- Pixel conversion only. Original EXIF, GPS, XMP and ICC profiles are not copied; processing uses 8-bit display pixels.
Common questions
Will every source image be exported?
Only one image is decoded; a concatenated image sequence is not exported as a complete set.
Can conversion restore colour or missing shades?
The source stores grayscale or bitonal values. A colour-capable JPEG XL can represent these tones, but conversion cannot infer original scene colours or recover missing intermediate shades. Colourisation would be a separate image-editing operation.
Will the background become transparent?
The target can store an alpha channel, but converting an opaque image does not create transparent areas. Removing a background is a separate editing step.
Are bit depth and colour values guaranteed to match?
Pixel conversion only. Original EXIF, GPS, XMP and ICC profiles are not copied; processing uses 8-bit display pixels.
Will metadata and colour profiles be retained?
Pixel conversion only. Original EXIF, GPS, XMP and ICC profiles are not copied; processing uses 8-bit display pixels.