Function decodeASTC

tests/ktxdiff/ktxdiff_main.cpp:274–321

}

auto decodeASTC(const char* compressedData, std::size_t compressedSize, uint32_t width, uint32_t height,
        const std::string& filepath, bool isFormatSRGB, uint32_t blockSizeX, uint32_t blockSizeY, uint32_t blockSizeZ) {

    const auto threadCount = 1u;
    static constexpr astcenc_swizzle swizzle{ASTCENC_SWZ_R, ASTCENC_SWZ_G, ASTCENC_SWZ_B, ASTCENC_SWZ_A};

    astcenc_error ec = ASTCENC_SUCCESS;

    const astcenc_profile profile = isFormatSRGB ? ASTCENC_PRF_LDR_SRGB : ASTCENC_PRF_LDR;
    astcenc_config config{};
    ec = astcenc_config_init(profile, blockSizeX, blockSizeY, blockSizeZ, ASTCENC_PRE_MEDIUM, ASTCENC_FLG_DECOMPRESS_ONLY, &config);
    if (ec != ASTCENC_SUCCESS)
        error(EXIT_CODE_ERROR, "ktxdiff error \"{}\": astcenc_config_init: {}\n", filepath, astcenc_get_error_string(ec));

    struct ASTCencStruct {
        astcenc_context* context = nullptr;
        ~ASTCencStruct() {
            astcenc_context_free(context);
        }
    } astcenc;
    astcenc_context*& context = astcenc.context;

    ec = astcenc_context_alloc(&config, threadCount, &context);
    if (ec != ASTCENC_SUCCESS)
        error(EXIT_CODE_ERROR, "ktxdiff error \"{}\": astcenc_context_alloc: {}\n", filepath, astcenc_get_error_string(ec));

    astcenc_image image{};
    image.dim_x = width;
    image.dim_y = height;
    image.dim_z = 1; // 3D ASTC formats are currently not supported
    const auto uncompressedSize = width * height * 4 * sizeof(uint8_t);
    auto uncompressedBuffer = std::make_unique<uint8_t[]>(uncompressedSize);
    auto* bufferPtr = uncompressedBuffer.get();
    image.data = reinterpret_cast<void**>(&bufferPtr);
    image.data_type = ASTCENC_TYPE_U8;

    ec = astcenc_decompress_image(context, reinterpret_cast<const uint8_t*>(compressedData), compressedSize, &image, &swizzle, 0);
    if (ec != ASTCENC_SUCCESS)
        error(EXIT_CODE_ERROR, "ktxdiff error \"{}\": astcenc_decompress_image: {}\n", filepath, astcenc_get_error_string(ec));

    astcenc_decompress_reset(context);

    struct Result {
        std::unique_ptr<uint8_t[]> data;
        std::size_t size;
    };
    return Result{std::move(uncompressedBuffer), uncompressedSize};
}

CompareResult compareAstc(const char* lhs, const char* rhs, std::size_t size, uint32_t width, uint32_t height,
        const std::string& filepathLhs, const std::string& filepathRhs,