| |
| /* intel_init.c - SSE2 optimized filter functions |
| * |
| * Copyright (c) 2018 Cosmin Truta |
| * Copyright (c) 2016-2017 Glenn Randers-Pehrson |
| * Written by Mike Klein and Matt Sarett, Google, Inc. |
| * Derived from arm/arm_init.c |
| * |
| * This code is released under the libpng license. |
| * For conditions of distribution and use, see the disclaimer |
| * and license in png.h |
| */ |
| |
| #include "../pngpriv.h" |
| |
| #ifdef PNG_READ_SUPPORTED |
| #if PNG_INTEL_SSE_IMPLEMENTATION > 0 |
| |
| void |
| png_init_filter_functions_sse2(png_structp pp, unsigned int bpp) |
| { |
| /* The techniques used to implement each of these filters in SSE operate on |
| * one pixel at a time. |
| * So they generally speed up 3bpp images about 3x, 4bpp images about 4x. |
| * They can scale up to 6 and 8 bpp images and down to 2 bpp images, |
| * but they'd not likely have any benefit for 1bpp images. |
| * Most of these can be implemented using only MMX and 64-bit registers, |
| * but they end up a bit slower than using the equally-ubiquitous SSE2. |
| */ |
| png_debug(1, "in png_init_filter_functions_sse2"); |
| if (bpp == 3) |
| { |
| pp->read_filter[PNG_FILTER_VALUE_SUB-1] = png_read_filter_row_sub3_sse2; |
| pp->read_filter[PNG_FILTER_VALUE_AVG-1] = png_read_filter_row_avg3_sse2; |
| pp->read_filter[PNG_FILTER_VALUE_PAETH-1] = |
| png_read_filter_row_paeth3_sse2; |
| } |
| else if (bpp == 4) |
| { |
| pp->read_filter[PNG_FILTER_VALUE_SUB-1] = png_read_filter_row_sub4_sse2; |
| pp->read_filter[PNG_FILTER_VALUE_AVG-1] = png_read_filter_row_avg4_sse2; |
| pp->read_filter[PNG_FILTER_VALUE_PAETH-1] = |
| png_read_filter_row_paeth4_sse2; |
| } |
| |
| /* No need optimize PNG_FILTER_VALUE_UP. The compiler should |
| * autovectorize. |
| */ |
| } |
| |
| #endif /* PNG_INTEL_SSE_IMPLEMENTATION > 0 */ |
| #endif /* PNG_READ_SUPPORTED */ |
