Multiple source images
Only one image is decoded; a concatenated image sequence is not exported as a complete set.
Convert PGM to QOI
- In your browser
- No upload
- Private by design
What happens when you convert PGM to QOI?
No new colour information
The source stores grayscale or bitonal values. A colour-capable QOI 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.
Lossless sample storage
QOI preserves 8-bit RGB/RGBA samples losslessly. Reducing 16-bit data or discarding profiles and metadata before encoding is outside that guarantee. QOI can store its supported image samples without lossy compression. This applies after rendering and sample conversion: it does not guarantee preservation of source precision, colour space or document structure, and cannot undo earlier losses.
PGM
Source
PGM
Portable Graymap
Compression: UncompressedTransparency: NoMetadata: Header, Comments
Portable Graymap: simple uncompressed raster samples for image-processing pipelines.
Explore PGM format →QOI
Target
QOI
Quite OK Image Format
Compression: LosslessTransparency: YesMetadata: Colour-space flag
A small lossless codec for 8-bit RGB and RGBA images, designed for simple, fast implementations.
Explore QOI format →Is PGM → QOI right for you?
Good choice when
- QOI fits your delivery use: Application assets & simple decoding.
- You can choose the source image or part needed for delivery.
- You need the existing gray or binary image in a compatible delivery format.
- You need lossless storage of the rendered samples supported by QOI.
- You need a QOI-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 expect lossless encoding to restore lost details or editing structure.
- You need higher-precision samples for grading or measurement.
- You expect automatic background removal or transparency.
PGM to QOI 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 QOI 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.
- Lossless sample storage
- QOI preserves 8-bit RGB/RGBA samples losslessly. Reducing 16-bit data or discarding profiles and metadata before encoding is outside that guarantee. QOI can store its supported image samples without lossy compression. This applies after rendering and sample conversion: it does not guarantee preservation of source precision, colour space or document structure, and cannot undo earlier losses.
- 8-bit destination samples
- Pixel conversion only. Original EXIF, GPS, XMP and ICC profiles are not copied; processing uses 8-bit display pixels.
- 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 → QOI: 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. QOI: QOI preserves 8-bit RGB/RGBA samples losslessly. Reducing 16-bit data or discarding profiles and metadata before encoding is outside that guarantee.
- Transparency
- Transparency is replaced with white by default. Change the background in Advanced options.
- Colour depth
- PGM: maxval up to 65535 → QOI: 8 bits/sample
- 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 QOI 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.