| # 3.x series change log |
| |
| This page summarizes the major functional and performance changes in each |
| release of the 3.x series. |
| |
| All performance data on this page is measured on an Intel Core i5-9600K |
| clocked at 4.2 GHz, running `astcenc` using AVX2 and 6 threads. |
| |
| <!-- ---------------------------------------------------------------------- --> |
| ## 3.7 |
| |
| **Status:** April 2022 |
| |
| 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). |
| |
| * **General:** |
| * **Feature:** The command line tool PNG loader has been switched to use |
| the Wuffs library, which is robust and significantly faster than the |
| current stb_image 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. |
| |
| ### Performance: |
| |
| Key for charts: |
| |
| * Color = block size (see legend). |
| * Letter = image format (N = normal map, G = grayscale, L = LDR, H = HDR). |
| |
| **Relative performance vs 3.5 release:** |
| |
|  |
| |
| <!-- ---------------------------------------------------------------------- --> |
| ## 3.6 |
| |
| **Status:** April 2022 |
| |
| 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. |
| |
| * **General:** |
| * **Feature:** Data tables are now optimized for contexts without the |
| `SELF_DECOMPRESS_ONLY` flag set. The flag therefore no longer improves |
| compression performance, but still reduces context creation time and |
| context data table memory footprint. |
| * **Feature:** Image quality for 4x4 `-fastest` configuration 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. |
| |
| ### Performance: |
| |
| Key for charts: |
| |
| * Color = block size (see legend). |
| * Letter = image format (N = normal map, G = grayscale, L = LDR, H = HDR). |
| |
| **Relative performance vs 3.5 release:** |
| |
|  |
| |
| <!-- ---------------------------------------------------------------------- --> |
| ## 3.5 |
| |
| **Status:** March 2022 |
| |
| 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. |
| |
| * **General:** |
| * **Feature:** Compressor configurations using `SELF_DECOMPRESS_ONLY` mode |
| store compacted partition tables, which significantly improves both |
| context create time and runtime performance. |
| * **Feature:** Bilinear infill for decimated weight grids supports a new |
| variant for half-decimated grids which are only decimated in one axis. |
| |
| ### Performance: |
| |
| Key for charts: |
| |
| * Color = block size (see legend). |
| * Letter = image format (N = normal map, G = grayscale, L = LDR, H = HDR). |
| |
| **Relative performance vs 3.4 release:** |
| |
|  |
| |
| |
| <!-- ---------------------------------------------------------------------- --> |
| ## 3.4 |
| |
| **Status:** February 2022 |
| |
| The 3.4 release introduces another round of optimizations, removing a number |
| of power-user configuration options to simplify the core compressor data path. |
| |
| 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 releases:** |
| * **Improvement:** Windows binaries changed to use ClangCL 12.0, which gives |
| up to 10% performance improvement. |
| |
| ### Performance: |
| |
| Key for charts: |
| |
| * Color = block size (see legend). |
| * Letter = image format (N = normal map, G = grayscale, L = LDR, H = HDR). |
| |
| **Relative performance vs 3.3 release:** |
| |
|  |
| |
| |
| <!-- ---------------------------------------------------------------------- --> |
| ## 3.3 |
| |
| **Status:** November 2021 |
| |
| 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 a constant color blocks. |
| |
| <!-- ---------------------------------------------------------------------- --> |
| ## 3.2 |
| |
| **Status:** August 2021 |
| |
| The 3.2 release is a bugfix release; no significant image quality or |
| performance differences are expected. |
| |
| * **General:** |
| * **Bug-fix:** Improved stability when new contexts were created while other |
| contexts were compressing or decompressing an image. |
| * **Bug-fix:** Improved stability when decompressing blocks with invalid |
| block encodings. |
| |
| <!-- ---------------------------------------------------------------------- --> |
| ## 3.1 |
| |
| **Status:** July 2021 |
| |
| The 3.1 release gives another performance boost, typically between 5 and 20% |
| faster than the 3.0 release, as well as further incremental improvements to |
| image quality. A number of build system improvements make astcenc easier and |
| faster to integrate into other projects as a library, including support for |
| building universal binaries on macOS. Full change list is shown below. |
| |
| 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:** RGB color data now supports `-perceptual` operation. The |
| current implementation is simple, weighting color channel errors by their |
| contribution to perceived luminance. This mimics the behavior of the human |
| visual system, which is most sensitive to green, then red, then blue. |
| * **Feature:** Codec supports a new low weight search mode, which is a |
| simpler weight assignment for encodings with a low number of weights in the |
| weight grid. The weight threshold can be overridden using the new |
| `-lowweightmodelimit` command line option. |
| * **Feature:** All platform builds now support building a native binary. |
| Native binaries automatically select the SIMD level based on the default |
| configuration of the compiler in use. Native binaries built on one machine |
| may use different SIMD options than native binaries build on another. |
| * **Feature:** macOS platform builds now support building universal binaries |
| containing both `x86_64` and `arm64` target support. |
| * **Feature:** Building the command line can be disabled when using as a |
| library in another project. Set `-DCLI=OFF` during the CMake configure |
| step. |
| * **Feature:** A standalone minimal example of the core codec API usage has |
| been added in the `./Utils/Example/` directory. |
| * **Core API:** |
| * **Feature:** Config flag `ASTCENC_FLG_USE_PERCEPTUAL` works for color data. |
| * **Feature:** Config option `tune_low_weight_count_limit` added. |
| * **Feature:** New heuristic added which prunes dual weight plane searches if |
| they are unlikely to help. This heuristic is not user controllable. |
| * **Feature:** Image quality has been improved. In general we see significant |
| improvements (up to 0.2dB) for high bitrate encodings (4x4, 5x4), and a |
| smaller improvement (up to 0.1dB) for lower bitrate encodings. |
| * **Bug fix:** Arm "none" SIMD builds could be invariant with other builds. |
| This fix has also been back-ported to the 2.x LTS branch. |
| |
| ### Performance: |
| |
| Key for charts: |
| |
| * Color = block size (see legend). |
| * Letter = image format (N = normal map, G = grayscale, L = LDR, H = HDR). |
| |
| **Relative performance vs 3.0 release:** |
| |
|  |
| |
| <!-- ---------------------------------------------------------------------- --> |
| ## 3.0 |
| |
| **Status:** June 2021 |
| |
| The 3.0 release is the first in a series of updates to the compressor that are |
| making more radical changes than we felt we could make with the 2.x series. |
| The primary goals of the 3.x series are to keep the image quality ~static or |
| better compared to the 2.5 release, but continue to improve performance. |
| |
| 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:** The code has been significantly cleaned up, with improved |
| comments, API documentation, function naming, and variable naming. |
| * **Core API:** |
| * **API Change:** The core APIs for `astcenc_compress_image()` and for |
| `astcenc_decompress_image()` now accept swizzle structures by `const` |
| pointer, instead of pass-by-value. |
| * **API Change:** Calling the `astcenc_compress_reset()` and the |
| `astcenc_decompress_reset()` functions between images is no longer required |
| if the context was created for use by a single thread. |
| * **Feature:** New heuristics have been added for controlling when to search |
| beyond 2 partitions and 1 plane, and when to search beyond 3 partitions and |
| 1 plane. The previous `tune_partition_early_out_limit` config option has |
| been removed, and replaced with two new options |
| `tune_2_partition_early_out_limit_factor` and |
| `tune_3_partition_early_out_limit_factor`. See command line help for more |
| detailed documentation. |
| * **Feature:** New heuristics have been added for controlling when to use |
| dual weight planes. The previous `tune_two_plane_early_out_limit` has been |
| renamed to`tune_2_plane_early_out_limit_correlation`. See command line help |
| for more detailed documentation. |
| * **Feature:** Support for using dual weight planes has been restricted to |
| single partition blocks; it rarely helps blocks with 2 or more partitions |
| and takes considerable compression search time. |
| |
| ### Performance: |
| |
| Key for charts: |
| |
| * Color = block size (see legend). |
| * Letter = image format (N = normal map, G = grayscale, L = LDR, H = HDR). |
| |
| **Relative performance vs 2.5 release:** |
| |
|  |
| |
| - - - |
| |
| _Copyright © 2021-2022, Arm Limited and contributors. All rights reserved._ |
