44 lines
1.2 KiB
C++
44 lines
1.2 KiB
C++
/* SPDX-FileCopyrightText: 2025 Blender Authors
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*
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* SPDX-License-Identifier: GPL-2.0-or-later */
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#pragma once
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/** \file
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* \ingroup bli
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*
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* Utilities for lossless data compression.
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*/
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#include <cstddef>
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#include <cstdint>
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namespace blender {
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/**
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* Transforms array of data, making it more compressible,
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* especially if data is smoothly varying. Typically you do
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* this before compression with a general purpose compressor.
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*
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* Transposes input array so that output data is first byte of
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* all items, then 2nd byte of all items, etc. And successive
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* items within each "byte stream" are stored as difference
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* from previous byte.
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*
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* See https://aras-p.info/blog/2023/03/01/Float-Compression-7-More-Filtering-Optimization/
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* for details.
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*/
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void filter_transpose_delta(const uint8_t *src, uint8_t *dst, size_t items_num, size_t item_size);
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/**
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* Reverses the data transform done by #unfilter_transpose_delta.
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* Typically you do this after decompression with a general purpose
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* compressor.
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*/
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void unfilter_transpose_delta(const uint8_t *src,
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uint8_t *dst,
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size_t items_num,
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size_t item_size);
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} // namespace blender
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