How to Convert PGM to HEIF

PGM's uncompressed storage makes even simple grayscale research output far larger than necessary, while HEIF's HEVC-based compression can shrink that same content dramatically, often to a small fraction of the original PGM file size. This conversion is mainly useful for archiving finished research or computer vision results once active processing is complete, rather than as part of an active technical workflow.

Since most Netpbm-based tools and command-line pipelines expect PGM directly rather than HEIF, this conversion works best as a final archival step after the processing work is done.

1. Install Turbo Batch Image Converter Pro on your Windows PC.
2. Open the app and select Batch Mode for multiple files, or Individual Mode for a single PGM.
3. Drag your PGM file or folder into the app window, enabling recursive folder scanning if needed.
4. Set the "From" format to PGM and the "To" format to HEIF.
5. Adjust the quality setting to balance file size against visual detail.
6. Click Convert. HEIF files are written to the output folder, fully offline.

• 100% offline — your research and pipeline output is never uploaded anywhere
• Significant storage savings compared to uncompressed PGM
• Bulk conversion of entire folders, including sub-folders, in one pass
• Multi-core processing for fast handling of large batches
• Option to delete original PGM files automatically once converted
• No recurring subscription or hidden upload limits