# Changelog All notable changes to this project will be documented in this file. The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/), and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html). ## Unreleased ### Added - decoder API: new function `JxlDecoderSetImageBitDepth` to set the bit depth of the output buffer. - decoder API proposal: add `JxlDecoderSetOutputColorProfile` and `JxlDecoderSetCms` to enable decoding to desired colorspace; NB: not implemented yet. - encoder API: new function `JxlEncoderSetFrameBitDepth` to set the bit depth of the input buffer. - encoder API: add an effort 10 option for lossless compression; using this setting requires calling `JxlEncoderAllowExpertOptions`. - encoder API: new `JXL_ENC_FRAME_SETTING_JPEG_COMPRESS_BOXES` enum value to allow explicit control of metadata compression ### Removed - common API: removed `JxlIntrinsicSizeHeader` - decoder API: removed deprecated `JXL_DEC_NEED_DC_OUT_BUFFER` and `JXL_DEC_DC_IMAGE` events, `JxlDecoderDCOutBufferSize` and `JxlDecoderSetDCOutBuffer` functions ### Changed / clarified - encoder API: `JxlEncoderProcessOutput` requires at least 32 bytes of output space to proceed and guarantees that at least one byte will be written ## [0.7] - 2022-07-21 ### Added - Export version information in headers. - decoder API: Ability to decode the content of metadata boxes: `JXL_DEC_BOX`, `JXL_DEC_BOX_NEED_MORE_OUTPUT`, `JxlDecoderSetBoxBuffer`, `JxlDecoderGetBoxType`, `JxlDecoderGetBoxSizeRaw` and `JxlDecoderSetDecompressBoxes`. - decoder API: ability to mark the input is finished: `JxlDecoderCloseInput`. - decoder API: ability to request updates on different progressive events using `JxlDecoderSetProgressiveDetail`; currently supported events are `kDC`, `kLastPasses` and `kPasses`. - decoder API: ability to specify desired intensity target using `JxlDecoderSetDesiredIntensityTarget` - decoder API: new function `JxlDecoderSetCoalesced` to allow decoding non-coalesced (unblended) frames, e.g. layers of a composite still image or the cropped frames of a recompressed GIF/APNG. - decoder API: new function `JxlDecoderSetUnpremultiplyAlpha` to set preference for getting an associated alpha channel with premultiplied or unpremultiplied colors. - decoder API: field added to `JxlFrameHeader`: a `JxlLayerInfo` struct that contains crop dimensions and offsets and blending information for the non-coalesced case. - decoder API: new function `JxlDecoderGetExtraChannelBlendInfo` to get the blending information for extra channels in the non-coalesced case. - decoder API: new function `JxlDecoderSetMultithreadedImageOutCallback`, allowing output callbacks to receive more information about the number of threads on which they are running. - decoder API: new function `JxlDecoderSkipCurrentFrame` to skip processing the current frame after a progressive detail is reached. - decoder API: new function `JxlDecoderGetIntendedDownsamplingRatio` to get the intended downsampling ratio of progressive steps, based on the information in the frame header. - decoder API: new function `JxlDecoderSetRenderSpotcolors` to allow disabling rendering of spot colors. - decoder/encoder API: add two fields to `JXLBasicInfo`: `intrinsic_xsize` and `intrinsic_ysize` to signal the intrinsic size. - encoder API: ability to add metadata boxes, added new functions `JxlEncoderAddBox`, `JxlEncoderUseBoxes`, `JxlEncoderCloseBoxes` and `JxlEncoderCloseFrames`. - encoder API: added ability to set several encoder options / extra fields to frames using `JxlEncoderSetFrameName`, `JxlEncoderFrameSettingsSetOption`, `JxlEncoderFrameSettingsSetFloatOption`. - encoder API: added ability to check required codestream compatibility level and force specified using `JxlEncoderGetRequiredCodestreamLevel` and `JxlEncoderSetCodestreamLevel`. - encoder API: added ability to force emitting box-based container format using `JxlEncoderUseContainer`. - encoder API: added ability to store JPEG metadata for lossless reconstruction using `JxlEncoderStoreJPEGMetadata` - encoder API: new functions `JxlEncoderSetFrameHeader` and `JxlEncoderSetExtraChannelBlendInfo` to set animation and blending parameters of the frame, and `JxlEncoderInitFrameHeader` and `JxlEncoderInitBlendInfo` to initialize the structs to set. - encoder API: ability to encode arbitrary extra channels: `JxlEncoderInitExtraChannelInfo`, `JxlEncoderSetExtraChannelInfo`, `JxlEncoderSetExtraChannelName` and `JxlEncoderSetExtraChannelBuffer`. - encoder API: ability to plug custom CMS implementation using `JxlEncoderSetCms(JxlEncoder* enc, JxlCmsInterface cms)` - encoder API: added `JxlEncoderGetError` to retrieve last encoder error. ### Changed - decoder API: using `JxlDecoderCloseInput` at the end of all input is required when using JXL_DEC_BOX, and is now also encouraged in other cases, but not required in those other cases for backwards compatibility. - encoder API: `JxlEncoderCloseInput` now closes both frames and boxes input. - CLI: `cjxl` and `djxl` have been reimplemented on the base of public decoder and encoder API; dropped dependency on `gflags` for argument parsing. ### Deprecated - decoder API: `JXL_DEC_EXTENSIONS` event: use `JXL_DEC_BASIC_INFO` - decoder / encoder API: pixel types `JXL_TYPE_BOOLEAN` and `JXL_TYPE_UINT32`: consider using `JXL_TYPE_UINT8` and `JXL_TYPE_FLOAT` correspondingly. - decoder API: pixel format parameter for `JxlDecoderGetColorAsEncodedProfile` and `JxlDecoderGetICCProfileSize`: pass `NULL`. - decoder API: `JxlDecoderDefaultPixelFormat` - encoder API: `JxlEncoderOptions`: use `JxlEncoderFrameSettings` instead. - encoder API: `JxlEncoderOptionsCreate`: use `JxlEncoderFrameSettingsCreate` instead. - encoder API: `JxlEncoderOptionsSetDistance`: use `JxlEncoderSetFrameDistance` instead. - encoder API: `JxlEncoderOptionsSetLossless`: use `JxlEncoderSetFrameLossless` instead. - encoder API: `JxlEncoderOptionsSetEffort`: use `JxlEncoderFrameSettingsSetOption(frame_settings, JXL_ENC_FRAME_SETTING_EFFORT, effort)` instead. - encoder API: `JxlEncoderOptionsSetDecodingSpeed`: use `JxlEncoderFrameSettingsSetOption(frame_settings, JXL_ENC_FRAME_SETTING_DECODING_SPEED, tier)` instead. - encoder API: deprecated `JXL_ENC_NOT_SUPPORTED`, the encoder returns `JXL_ENC_ERROR` instead and there is no need to handle `JXL_ENC_NOT_SUPPORTED`. ## [0.6.1] - 2021-10-29 ### Changed - Security: Fix OOB read in splines rendering (#735 - [CVE-2021-22563](https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-22563)) - Security: Fix OOB copy (read/write) in out-of-order/multi-threaded decoding (#708 - [CVE-2021-22564](https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-22564)) - Fix segfault in `djxl` tool with `--allow_partial_files` flag (#781). - Fix border in extra channels when using upsampling (#796) ## [0.6] - 2021-10-04 ### Added - API: New functions to decode extra channels: `JxlDecoderExtraChannelBufferSize` and `JxlDecoderSetExtraChannelBuffer`. - API: New function `JxlEncoderInitBasicInfo` to initialize `JxlBasicInfo` (only needed when encoding). NOTE: it is now required to call this function when using the encoder. Padding was added to the struct for forward compatibility. - API: Support for encoding oriented images. - API: FLOAT16 support in the encoder API. - Rewrite of the GDK pixbuf loader plugin. Added proper color management and animation support. - Rewrite of GIMP plugin. Added compression parameters dialog and switched to using the public C API. - Debian packages for GDK pixbuf loader (`libjxl-gdk-pixbuf`) and GIMP (`libjxl-gimp-plugin`) plugins. - `cjxl`/`djxl` support for `stdin` and `stdout`. ### Changed - API: Renamed the field `alpha_associated` in `JxlExtraChannelInfo` to `alpha_premultiplied`, to match the corresponding name in `JxlBasicInfo`. - Improved the 2x2 downscaling method in the encoder for the optional color channel resampling for low bit rates. - Fixed: the combination of floating point original data, XYB color encoding, and Modular mode was broken (in both encoder and decoder). It now works. NOTE: this can cause the current encoder to write jxl bitstreams that do not decode with the old decoder. In particular this will happen when using cjxl with PFM, EXR, or floating point PSD input, and a combination of XYB and modular mode is used (which caused an encoder error before), e.g. using options like `-m -q 80` (lossy modular), `-d 4.5` or `--progressive_dc=1` (modular DC frame), or default lossy encoding on an image where patches end up being used. There is no problem when using cjxl with PNG, JPEG, GIF, APNG, PPM, PGM, PGX, or integer (8-bit or 16-bit) PSD input. - `libjxl` static library now bundles skcms, fixing static linking in downstream projects when skcms is used. - Spline rendering performance improvements. - Butteraugli changes for less visual masking. ## [0.5] - 2021-08-02 ### Added - API: New function to decode the image using a callback outputting a part of a row per call. - API: 16-bit float output support. - API: `JxlDecoderRewind` and `JxlDecoderSkipFrames` functions to skip more efficiently to earlier animation frames. - API: `JxlDecoderSetPreferredColorProfile` function to choose color profile in certain circumstances. - encoder: Adding `center_x` and `center_y` flags for more control of the tile order. - New encoder speeds `lightning` (1) and `thunder` (2). ### Changed - Re-licensed the project under a BSD 3-Clause license. See the [LICENSE](LICENSE) and [PATENTS](PATENTS) files for details. - Full JPEG XL part 1 specification support: Implemented all the spec required to decode files to pixels, including cases that are not used by the encoder yet. Part 2 of the spec (container format) is final but not fully implemented here. - Butteraugli metric improvements. Exact numbers are different from previous versions. - Memory reductions during decoding. - Reduce the size of the jxl_dec library by removing dependencies. - A few encoding speedups. - Clarify the security policy. - Significant encoding improvements (~5 %) and less ringing. - Butteraugli metric to have some less masking. - `cjxl` flag `--speed` is deprecated and replaced by the `--effort` synonym. ### Removed - API for returning a downsampled DC was deprecated (`JxlDecoderDCOutBufferSize` and `JxlDecoderSetDCOutBuffer`) and will be removed in the next release. ## [0.3.7] - 2021-03-29 ### Changed - Fix a rounding issue in 8-bit decoding. ## [0.3.6] - 2021-03-25 ### Changed - Fix a bug that could result in the generation of invalid codestreams as well as failure to decode valid streams. ## [0.3.5] - 2021-03-23 ### Added - New encode-time options for faster decoding at the cost of quality. - Man pages for cjxl and djxl. ### Changed - Memory usage improvements. - Faster decoding to 8-bit output with the C API. - GIMP plugin: avoid the sRGB conversion dialog for sRGB images, do not show a console window on Windows. - Various bug fixes. ## [0.3.4] - 2021-03-16 ### Changed - Improved box parsing. - Improved metadata handling. - Performance and memory usage improvements. ## [0.3.3] - 2021-03-05 ### Changed - Performance improvements for small images. - Add a (flag-protected) non-high-precision mode with better speed. - Significantly speed up the PQ EOTF. - Allow optional HDR tone mapping in djxl (--tone_map, --display_nits). - Change the behavior of djxl -j to make it consistent with cjxl (#153). - Improve image quality. - Improve EXIF handling. ## [0.3.2] - 2021-02-12 ### Changed - Fix embedded ICC encoding regression [#149](https://gitlab.com/wg1/jpeg-xl/-/issues/149). ## [0.3.1] - 2021-02-10 ### Changed - New experimental Butteraugli API (`jxl/butteraugli.h`). - Encoder improvements to low quality settings. - Bug fixes, including fuzzer-found potential security bug fixes. - Fixed `-q 100` and `-d 0` not triggering lossless modes. ## [0.3] - 2021-01-29 ### Changed - Minor change to the Decoder C API to accommodate future work for other ways to provide input. - Future decoder C API changes will be backwards compatible. - Lots of bug fixes since the previous version. ## [0.2] - 2020-12-24 ### Added - JPEG XL bitstream format is frozen. Files encoded with 0.2 will be supported by future versions. ### Changed - Files encoded with previous versions are not supported. ## [0.1.1] - 2020-12-01 ## [0.1] - 2020-11-14 ### Added - Initial release of an encoder (`cjxl`) and decoder (`djxl`) that work together as well as a benchmark tool for comparison with other codecs (`benchmark_xl`). - Note: JPEG XL format is in the final stages of standardization, minor changes to the codestream format are still possible but we are not expecting any changes beyond what is required by bug fixing. - API: new decoder API in C, check the `examples/` directory for its example usage. The C API is a work in progress and likely to change both in API and ABI in future releases.