📰 Picopt News¶

v6.7.0¶

Features¶

• JPEG XL support, read and write, using the internal pillow-jxl-plugin module.
• JXL is now optimized by default. .jxl files that previous versions ignored are re-encoded on a plain picopt -r run. Only lossless JXL is touched; lossy (XYB encoded) JXL is left alone, as lossy WebP is.
• Lossless images convert to JXL with -c JXL, which now leads the preference order for still images ahead of WEBP and PNG.
• New --convert-jpeg-to-jxl converts JPEG to JXL losslessly and reversibly: the JXL stores the original JPEG bitstream and can restore it byte for byte. Files carrying that reconstruction data are never re-encoded, so the original JPEG stays recoverable.
• New --convert-webp-to-jxl converts lossless WebP to JXL. Off by default because JXL support is still much thinner than WebP’s.
• Both flags require -c JXL as well. JPEG and WEBP are formats picopt already processes by default, so unlike BMP or TIFF they cannot be gated by naming them with -x. A plain -c JXL still converts only GIF and PNG.

v6.6.3¶

Fixes¶

• Corrupt images that PIL recognizes but cannot parse (e.g. a BMP with an unsupported pixel depth) are reported as a one-line warning and counted in the summary instead of dumping a stack trace.

v6.6.2¶

Fixes¶

• Timestamps are no longer silently invalidated when options come from a tree root’s .picopt.yaml instead of identical CLI flags: the config check now compares each tree’s effective configuration, directory configs included.
• timestamps: true in a tree root’s .picopt.yaml (e.g. written by -W -t) now enables timestamping for that tree without -t. CLI flags still win, and --dry-run / --list still disable stamping.
• Timestamp invalidation is now per tree and value-based: comment or formatting edits to .picopt.yaml files, rewriting them with -W, or running with a different set of top paths no longer invalidate stamps — only actual option changes do.
• Discarding stamps because the configuration changed now prints a warning naming the differing options instead of silently re-optimizing.
• Verbose timestamps, ignores, after, and memory budget summaries are no longer repeated once per directory when using per-directory .picopt.yaml files.

Migration note¶

• Existing timestamp files will mismatch once after this upgrade because the stored config changed shape. Either let the first timestamped run re-examine each tree once, or run once with -N (--timestamps-no-check-config) to keep the old stamps.

v6.6.1¶

Fixes¶

• Animated WebP images with zero-duration frames no longer fail to optimize.
• The Optimizing formats summary is no longer repeated once per directory when using -W or per-directory .picopt.yaml files.

v6.6.0¶

Fixes¶

• Files are now replaced atomically: a crash, kill, or full disk mid-write can no longer destroy the original image.
• Archive members whose optimization fails are kept in the repacked archive; previously they were silently dropped.
• Nested archives (e.g. a CBZ inside a ZIP) now optimize; previously they always errored.
• Archives keep their comments and member order through repack; tar symlinks and hardlinks survive; 7z member times are preserved; pre-1980 member times no longer crash conversion; legacy non-UTF8 zip member names are repaired.
• Archive conversions compress each member by content; converting a rar, tar, or 7z no longer leaves every member stored uncompressed.
• Files that fail to optimize are retried on the next timestamped run; previously directory timestamps covered them and they were skipped forever.
• One corrupt file inside an archive (e.g. a decompression bomb) no longer aborts the entire run.
• Boolean options set in config files or environment variables are no longer ignored.
• Requested archive conversions (e.g. CBR to CBZ) now happen even when the contents are already optimized.
• Lossless WebPs with large metadata inside archives are no longer misdetected as lossy.
• Owner-password-restricted PDFs keep their encryption; optimized PDF images keep their color transform; more signed PDFs are detected and refused.
• svgo no longer strips viewBox, and keeps title/desc metadata unless --strip-metadata is given.
• Conversions discarded for being bigger (and dry runs) are reported as skips, not errors.
• --preserve no longer fails as a non-root user when it cannot change ownership; it still restores permissions and modification time.
• Temporary files and animated-WebP frame directories are cleaned up when a tool fails or a run is cancelled, instead of leaking to disk.
• picopt doctor no longer reports missing tools and exits nonzero on healthy installs.
• Symlink loops, unreadable directories, and FIFOs no longer hang or crash the walk.
• Bad --memory-limit and --after values abort with clean error messages; timezone-aware --after values are honored; lowercase format lists are accepted for -x and -c.
• -I/--no-default-ignores without -i no longer aborts at startup.
• Existing timestamps are invalidated once after upgrading because the timestamp config check gained new keys; the first -t run re-examines already-optimized trees.

Features¶

• Per-directory .picopt.yaml config files: pin any setting to a directory tree. Deeper directories win; environment variables and the command line still override. Editing one re-processes its tree on timestamped runs.
• Write your invoked options to config files: -w to the user config, -W to a .picopt.yaml in each target directory, --write-config-file PATH to an explicit path.
• Memory-aware scheduling: picopt now estimates the peak memory of large archives and limits how many run at once so big libraries (e.g. multi-GB comic archives) no longer exhaust RAM and get the process OOM-killed. Tune the budget with the new --memory-limit option (e.g. --memory-limit 8G), which reads as an approximate peak-memory target; the default is two-thirds of detected RAM.
• Incremental archive re-optimization: when a timestamped archive changes, members older than its timestamp are skipped instead of re-optimized; -E disables the member check. Timestamp files found inside archives are consumed and removed on repack.

Performance¶

• Archive member format detection runs in parallel workers instead of serializing the scheduler.
• Solid 7z archives extract in one pass instead of decompressing from the start for every member.
• The progress pre-scan is skipped in quiet mode, less image data is shipped between processes, and scheduling under a memory limit no longer rescans the whole queue on every completion.

v6.5.2¶

• Update to latest oxipng v10

v6.5.1¶

• Fix data loss when converting without external tools.
• Show platform-specific install hints in picopt doctor for missing tools.

v6.5.0¶

• Faster PDF detection
• Faster metadata extraction
• Defer animated image duration doublecheck to only WebP animated and only at handler time. Speeds up other animated images.
• Use rich_argparse to format cli help.

v6.4.0¶

• Update to Confuse 2.2.0
• Introduce new PicoptSettings class to type the config.

v6.3.1¶

• Fix frame duration erroneously extracted for MPO format, causing an error.

v6.3.0¶

• New progress and logging

v6.2.0¶

• Add bunx support for svgo
• Fix multiprocessing crash when using timestamps with some archives.
• Print stack traces when errors occur.

v6.1.1¶

• Treestamps 3.0.0

v6.1.0¶

• Rewote multiprocessing to enable more throughput.
• Added fail fast options for the entire workflow or only containers.

v6.0.0¶

• Picopt now recompresses PDFs and their image contents losslessly.
• Picopt now skips writing timestamps if no other disk writing operation occurred.
• Picopt doctor command shows what optimization tools are available.
• New architecture uses discoverable plugins to keep behavior contained in plugin files rather than spread out across the codebase.

v5.3.2¶

• Add option –timestamps-ignore-archive-entry-mtimes.
• Add type hints and py.typed sentinel file.

v5.3.1¶

• Fix incompatibility with Confuse v2.2.0
• Pin to Confuse v2.1.0 due to typing issues with Confuse v2.2.0

v5.3.0¶

• Use webpmux if available to unpack and repack animated webp images.
• Fix Animated WebP images:
  • Sometimes being repacked in reverse frame order.
  • Sometimes degrading quality.
  • Sometimes dropping frames.
• Use secure python temporary directory for unpacking animated webp images and chaining webp conversion input.
• Use img2webp if available for animated conversion to webp from png.
• Use memory buffers instead of disk for webp output.

v5.2.2¶

• Support Python 3.14

v5.2.1¶

• The confuse library dependency doesn’t support Python 3.14. So neither does picopt :(

v5.2.0¶

• MozJpeg is now an internal python module. External mozjpeg & jpegtran support removed.

v5.1.1¶

• Fix verbosity default too high.

v5.1.0¶

• Use gif2webp to convert GIFs to WebP. It saves space compared to picopt’s custom method.

v5.0.1¶

• Fix crash converting animated images with bad duration metadata.

v5.0.0¶

• Alert!
  • Timestamps options changed, invalidating old timestamps. On your first run in a path with picopt 5.0 you may use the -N option to ignore the old timestamp’s config differences.
• Fixes
  • Fix tif & animated gifs were not converted to pngs when specified.
  • Fix –ignore option wildcards and performance.
  • --ignore is now case insensitive on case insenstitive filesystems
• Features
  • Picopt learned to optimize 7-Zip and Tar Archives.
  • Ignore dotfiles by default. Disable with -I.
  • -T –test option becomes -d –dry-run
  • colors changed.
• Performance
  • Archives skipped without unpacking contents if all contents are skippable.
  • Animated pngs better optimized with oxipng
  • Faster scanning for legacy timestamps on startup.
• Dev
  • Updated treestamps
  • uv build system

v4.0.4¶

• Pillow 11 support.
• Better jpeg xmp preservation.
• Fix crash on reporting some errors.
• README Redhat installation and spelling fixes by @bpepple

v4.0.3 - Bad release¶

v4.0.2¶

• Fix windows mmap crash. Thanks @Fletcher.

v4.0.1¶

• Reduce overzealous png optimization. Provide an option to do that.

v4.0.0¶

• Alert!
  • Timestamps options changed, invalidating old timestamps. On your first run in a path with picopt 4.0 use the -N option to ignoring the old timestamp.
• Features
  • Support optimizing SVG with svgo.
  • Support converting more lossless formats to PNG & WEBP: CUR, DIB, FITS, IMT, PCX, PIXAR, PSD, QOI, SGI, SPIDER, SUN, TGA, XBM, XPM.
  • Support converting animated formats to animated PNG.
  • Support converting losslessly converting MPO to JPEG (choose primary image)
  • Internal oxipng replaces external optipng for png compression.
  • Better support for preserving EXIF, ICC_PROFILE, & XMP data across optimization and conversion.
  • --destroy-metadata option becomes --strip-metadata
  • --near-lossless option for lossless WebP.
  • --preserve file attributes after optimization.
  • --disable-programs option.
  • \~25% faster due to avoiding disk io.
• Fixes
  • wal file would write illegal key names and fail to load for some files.
• Dev
  • walk.run now returns totals instead of running report on them.

v3.3.7¶

• Fix
  • Remove Lossy WebP optimization. Wasn’t optimal.
  • Fix non zero exit code on success.
• Features
  • Improve WebP optimization.

v3.3.6¶

• If unrar is not available do not convert rar. Was making empty zips.
• Support zip deflate64

v3.3.5¶

• Wasn’t skipping directories appropriately.

v3.3.4¶

• Keep original path suffix if not converting.

v3.3.3¶

• Update treestamps fixes bugs.

v3.3.2¶

• Upstream treestamps returns to relative stamp paths for portability.

v3.3.1¶

• Upstream treestamps fixes crashes and check_config option.

v3.3.0¶

• Update deps including treestamps.
• New option to disable treestamps check of config section for a run.

v3.2.6¶

• Fix cleanup of temp dir when repacking a container or animated images fails.
• Simple error message instead of stack trace on config failure.

v3.2.5¶

• Fix occasionally removing both final and originals on case insensitive filesystem.

v3.2.4¶

• Fix error reporting
• Fix WebP Lossless detection

v3.2.3¶

• Color help. Change bigger color to blue.

v3.2.2¶

• Remove more debug print statements.

v3.2.1¶

• Remove debug print statements.

v3.2.0¶

• Animated PNG conversion to WEBP support
• Fixed showing total saved at the end
• Highlight conversions with color output
• Lowlight nothing saved results with dark colors
• Suppress stdout from programs
• Report errors in more detail
• Fixed verbosity count for cli
• Report on unhandled formats at verbosity > 1.

v3.1.4¶

• Remove extraneous debug print statement.

v3.1.3¶

• Fix not deleting working files
• Add progress dots to verbose level 1

v3.1.2¶

• Fix treestamps factory breaking.

v3.1.1¶

• Fix not skipping older than timestamp files.
• Add verbose logging skip files reason.

v3.1.0¶

• Change walk algorithm to complete directories and containers before opening new ones.
• Case insensitive format config.
• Ignore symlinks when asked to in timestamps.

v3.0.5¶

• Timestamps respect ignore option.
• Don’t record timestamps for items inside containers.
• Traverse directories alphabetically.

v3.0.4¶

• Fix timestamps not recording sometimes.

v3.0.3¶

• Don’t dump full timestamps after every dir completes.

v3.0.2¶

• Trap container repack errors.

v3.0.1¶

• Update treestamps to accept string paths.

v3.0.0¶

• Formats
  • WebP lossless, lossy and animated support.
  • Gain support for .zip archives
  • EPub support. ePub contents are never converted.
  • TIFF support
• Timestamps
  • Timestamps are now kept in .picopt_treestamps.yaml files.
  • Picopt will convert and clean up old style timestamps.
  • Timestamps are now recorded after optimizing every image for each image individually instead of directories, preserving progress.
  • Timestamps record configuration. Running with a new config invalidates non-matching timestamps.
• Configuration
  • .picoptrc.yaml files can configure options
  • Changed cli option names.
  • Removed cli args for manually disabling programs
  • Faster checking for external programs
• Fall back to Pillow optimization if better external programs not found.
• Colored terminal output.
• Fixes
  • Cleans up old temporary files from aborted picopt runs.
  • Fix condition where new files in an old archive were not processed.
  • optiping optimization level changed to o5
  • Exif & icc metadata preserved in all formats much better by default.

v2.2.1¶

• Support python v3.9
• Preserve comments when optimizing comic archives

v2.2.0¶

• Walk in alphabetical order
• Check code with vulture and radon

v2.1.0¶

• Remove adv support.
• Remove jpegrescan support. Inferior to mozjpeg
• Don’t preserve ctime/mtime when making new pngs
• Use pytest instead of nosetest
• Require formatting with black & isort

v2.0.1¶

• Pillow 7 compatibility

v2.0.0¶

• Stop supporting python 2
• Switch to poetry build system
• Type checking with mypy

v1.6.3¶

• Don’t use pngout on 16 bit pngs because it crashes
• Fix broken option -D –optimize_after

v1.6.2¶

• Fix illegal stack trace call.

v1.6.1¶

• Fix exception handling when extern process returns non-zero

v1.6.0¶

• Report on all errors at the end
• Remove PIL support in favor of Pillow.
• Python3 proof

v1.5.3¶

• Fix hang on external program error. Likely with 16 bit PNGs and pngout.

v1.5.2¶

• More compatibility with Python 3
• Fix formats as a list when it should be a set issue

v1.5.1¶

• Drop TIFF support.
• Fix space savings reporting bug where savings always equaled zero

v1.4.5¶

• When setting new timestamps, don’t remove timestamps above the root paths specified as input

v1.4.4¶

• Use timestamp caching more often

v1.4.3¶

• Fix bug where files were not detected
• Fix broken timestamp processing.

v1.4.1¶

• fix main entry bug for cli

v1.4.0¶

• let the archive date override the newness of its contained files.
• let the cli run programmatically with passed in args
• code no longer relies on cwd for finding its way
• -d –directory argument goes away
• nosetests now run the old inadequate cli tests
• big code cleanup
• don’t redetect new image format type

v1.3.3¶

• Print found picopt timestamps
• Lots of linting
• Fix jpeg_multithread flag
• moved tests out of picopt module

v1.3.2¶

• Keep version in one place in picopt/init.py

v1.3.1¶

• Remove dev dependencies from installed requirements.

v1.3¶

• break up monolithic picopt into modules. No functional change.

v1.2¶

• picopt learned the -j option for specifying number of subprocesses (thanks @DarwinAwardWinner)

v1.1.3¶

• fixed rare crash on sequential gif detection

v1.1.2¶

• detect PNM images properly for conversion with optipng

v1.1.1¶

• fix verifying gif crash (thanks @DarwinAwardWinner)

v1.1.0¶

• mozjpeg support (thanks to @crass00)

v1.0.6¶

• Fix disabled comic archive switch.

v1.0.5¶

• Fix timestamp writing to happen once workers have finished
• Fix size saved if size in is zero

v1.0.3¶

• Fix -v to actually be more verbose than default
• Fix from Dennis Schwertel to jpegtran runner

v1.0.2¶

• Fix -Y to actually disable not enable type conversion

v1.0.1¶

• Fix typos in –help

v1.0.0¶

• Packaging for PyPI
• Internal changes to make picopt more modular and library friendly
• CHANGED COMMAND LINE ARGUMENT LETTERS.
• Added verbosity setting
• Truncated relative and in-archive path names for readibiliy
• Nag about animated gifs less

v0.12.0.1¶

• Fix error on no directories

v0.12.0¶

• Added multithreaded jpegrescan operation when picopt isn’t using up all the cores at the suggestion of Alex Roe.
• Added destroy metadata option at the suggestion of Alex Roe.

v0.11.4¶

• Added to ArchLinux by Alex Roe.