Astc-encoder-py

The 3.7 release contains another round of performance optimizations, including significant improvements to the command line front-end (faster PNG loader) and the arm64 build of the codec (faster NEON implementation).

Change log

**General:**
* **Feature:** The command line tool PNG loader has been switched to use the Wuffs library, which is significantly faster than the current implementation.
* **Feature:** Support for non-invariant builds returns. Opt-in to slightly faster, but not bit-exact, builds by setting `-DNO_INVARIANCE=ON` for the CMake configuration. This improves performance by around 2%.
* **Optimization:** Changed SIMD `select()` so that it matches the default NEON behavior (bitwise select), rather than the default x86-64 behavior (lane select on MSB). Specialization `select_msb()` added for the one case we want to select on a sign-bit, where NEON needs a different implementation. This provides a significant (>25%) performance uplift on NEON implementations.

Binary release sha256 checksums


f69c2acbb3b07386cc95001c253cddfa567e71b9618682856f0ff600955cc2ba astcenc-3.7-linux-x64.zip
41c691613e15d844bac56e97a042cc8aea7bc7e8e76fc767ffe875a4d8c5e995 astcenc-3.7-macos-aarch64.zip
5608f4c0b3e1d56a30070cdf61aff42050576833ac7e2719031cec461aa4d102 astcenc-3.7-macos-x64.zip
ecb0e1a5dcbfbaca8a38630e427638380b9d337c266660b39738260e1df5244a astcenc-3.7-windows-x64.zip

The 3.6 release contains another round of performance optimizations. There are no interface changes in this release, but in general the API is not designed to be binary compatible across versions. We always recommend rebuilding your client-side code using the updated `astcenc.h` header.

Change log

**General:**
* **Feature:** Compressor configurations no longer require the `SELF_DECOMPRESS_ONLY` flag to use defragmented data tables. Tables are always sorted to store active data table entries at the start of the list, with inactive entries stores at the end. If the `SELF_DECOMPRESS_ONLY` flag is specified the inactive entries are not created, reducing context creation time and memory footprint.
* **Feature:** Image quality for 4x4 `-fastest` compression has been improved.
* **Optimization:** Decimation modes are reliably excluded from processing when they are only partially selected in the compressor configuration (e.g. if used for single plane, but not dual plane modes). This is a significant performance optimization for all quality levels.
* **Optimization:** Fast-path block load function variant added for 2D LDR images with no swizzle. This is a moderate performance optimization for the `-fast` and `-fastest` quality levels.

Binary release sha256 checksums


cd0392bccb64da8177f3e3869c5ac37aea6d096cbbf804ecc0b62b3581a2b56b astcenc-3.6-linux-x64.zip
a04c3e930ba7397fb0c33fa6a70bb64ff798cd42a031124164a164f81634930c astcenc-3.6-macos-aarch64.zip
b51f7f53c7c113f708666dca11dcaec545c535c081bc9b27030cf2eee73a279a astcenc-3.6-macos-x64.zip
2a9c1edf98e1d28d542fb728c88f9afc03c9de18e5662b348e44be3f1a227059 astcenc-3.6-windows-x64.zip

The 3.5 release contains another round of performance optimizations. There are no interface changes in this release, but in general the API is not designed to be binary compatible across versions. We always recommend rebuilding your client-side code using the updated astcenc.h header.

Change log

**General:**
* **Feature:** Compressor configurations using the `SELF_DECOMPRESS_ONLY` flag store compacted partition tables, which significantly improves both context creation time and compressor runtime performance.
* **Feature:** Bilinear infill for decimated weight grids supports a new variant for half-decimated grids which are only decimated in one axis, which gives a small performance boost across all quality levels.

Binary release sha256 checksums


08e4dc8e263c0dcb0dc8d9d63b194ff881b8737de8f554458b2d66935da9c4fe astcenc-3.5-linux-x64.zip
ced2d434cbade742ef1f3879f90918e983381ddec1cea794ea30e6d4b2fa9573 astcenc-3.5-macos-aarch64.zip
806d86f69d84d4c30d0e6f8ca7cfe222005e51ca86684e265dd5aa4b68f9ddcf astcenc-3.5-macos-x64.zip
b531b89a677a41535f2704d50677904ae7ffefe83b403dfbbf6bfe6b028d573d astcenc-3.5-windows-x64.zip

**Status:** Released

The 3.4 release introduces another round of optimizations, removing a number of power-user configuration options to simplify the core compressor data path. It is expected that there is some minor loss of image quality at the same compressor effort setting, but the improved performance allows a higher compressor effort level to be used for the same runtime as earlier releases.

Reminder for users of the library interface - the API is not designed to be binary compatible across versions, and this release is not compatible with earlier releases. Please update and rebuild your client-side code using the updated `astcenc.h` header.

* **General:**
* **Feature:** Many memory allocations have been moved off the stack into dynamically allocated working memory. This significantly reduces the peak stack usage, allowing the compressor to run in systems with 128KB stack limits.
* **Feature:** Builds now support `-DBLOCK_MAX_TEXELS=<count>` to allow a compressor to support a subset of block sizes. This can reduce binary size and runtime memory footprint, and improve performance.
* **Feature:** The `-v` and `-va` options to set a per-texel error weight function are no longer supported.
* **Feature:** The `-b` option to set a per-texel error weight boost for block border texels is no longer supported.
* **Feature:** The `-a` option to set a per-texel error weight based on texel alpha value is no longer supported as an error weighting tool, but is still supported for providing sprite-sheet RDO.
* **Feature:** The `-mask` option to set an error metric for mask map textures is still supported, but is currently a no-op in the compressor.
* **Feature:** The `-perceptual` option to set a perceptual error metric is still supported, but is currently a no-op in the compressor for mask map and normal map textures.
* **Bug-fix:** Corrected decompression of error blocks in some cases, so now returning the expected error color (magenta for LDR, NaN for HDR). Note that `astcenc` determines the error color to use based on the output image data type not the decoder profile.

Binary release sha256 checksums

**Note:** Due to a delay publishing the binaries, caused by a DevOps pipeline upgrade, these binaries have actually been built from a slightly newer git hash (`c82259f`) than the 3.4 tag. This includes a number of performance optimizations which didn't land in time for the 3.4 release tag, as well as a change to use ClangCL to compile the Windows builds.


ceb268d8eb393281bf5646450c17f64c7fbfeddad7f02c52c28ab1b74f129fce astcenc-3.4-linux-x64.zip
0619c92b1ba3c24f209c7affb21b56d29aeaef6bdbb1a73793cad560853e53c9 astcenc-3.4-macos-aarch64.zip
faf389fa734855fdf5c070920ad682c083d354d0b8e5310a6d4134cea1921485 astcenc-3.4-macos-x64.zip
d85c89f6a6251ccda71b3aace66502a7b54668b8bc23632180bfc48cebeb74de astcenc-3.4-windows-x64.zip

**Status:** Released

The 3.3 release improves image quality for normal maps, and two component textures. Normal maps are expected to compress 25% slower than the 3.2 release, although it should be noted that they are still faster to compress in 3.3 than when using the 2.5 series. This release also fixes one reported stability issue.

* **General:**
* **Feature:** Normal map image quality has been improved.
* **Feature:** Two component image quality has been improved, provided that unused components are correctly zero-weighted using e.g. `-cw` on the command line.
* **Bug-fix:** Improved stability when trying to compress complex blocks that could not beat even the starting quality threshold. These will now always compress in to constant color blocks.

Binary release sha256 checksums


d686330476b104b94ff74eadc79b1778bf36aa42eb6f3904dca36af05a4c8c87 astcenc-3.3-linux-x64.zip
0b9eb51e75a433e68b5f8659d95b6e315b12a2263617beb2bca4cc5fbd396c00 astcenc-3.3-macos-aarch64.zip
c7f150dc54bd26f177cc94dd9531c2f9ec94f419047d943be8822d9d62e2e65e astcenc-3.3-macos-x64.zip
71644196c3e8a9205844fbf407e9f41df1911c787ac055b664307b60c3e9155d astcenc-3.3-windows-x64.zip

**Status:** Released

The 3.2 release is the third release in the 3.x series. This release is a maintenance release, fixing two issues in the 3.1 release.

* **General:**
* **Bug fix:** Multi-context usage of the library could result in poor quality block encodings or decompressed images if a new context was allocated while an image was being compressed or decompressed using another context.
* **Bug fix:** Invalid block encodings that could not be encoded in the available bitrate are more consistently rejected during decompression.

Binary release sha256 checksums


a5de27ffd291bb2ae4d1ecd68e563ddfd60d1ead6022abe46d34ef141968ce6b astcenc-3.2-linuxx64.zip
2f4dee7aa61e9b0728a5f558520c117cd9107753ef5d8a2bbab502761dc21417 astcenc-3.2-macosaarch64.zip
0a76024c92e6205cad661481551051a84673e5dda1d0d83c6d0541d964b06a95 astcenc-3.2-macosx64.zip
1e6b526841f5f721a6c154df18ed5e0493e34539b3149fe1ad46f54e08d6bdf7 astcenc-3.2-windowsx64.zip