diff options
Diffstat (limited to 'thirdparty/libpng/arm/palette_neon_intrinsics.c')
-rw-r--r-- | thirdparty/libpng/arm/palette_neon_intrinsics.c | 149 |
1 files changed, 149 insertions, 0 deletions
diff --git a/thirdparty/libpng/arm/palette_neon_intrinsics.c b/thirdparty/libpng/arm/palette_neon_intrinsics.c new file mode 100644 index 0000000000..fa02d6a8b3 --- /dev/null +++ b/thirdparty/libpng/arm/palette_neon_intrinsics.c @@ -0,0 +1,149 @@ + +/* palette_neon_intrinsics.c - NEON optimised palette expansion functions + * + * Copyright (c) 2018 Cosmin Truta + * Copyright (c) 2017-2018 Arm Holdings. All rights reserved. + * Written by Richard Townsend <Richard.Townsend@arm.com>, February 2017. + * + * 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" + +#if PNG_ARM_NEON_IMPLEMENTATION == 1 + +#if defined(_MSC_VER) && defined(_M_ARM64) +# include <arm64_neon.h> +#else +# include <arm_neon.h> +#endif + +/* Build an RGBA palette from the RGB and separate alpha palettes. */ +void +png_riffle_palette_rgba(png_structrp png_ptr, png_row_infop row_info) +{ + png_const_colorp palette = png_ptr->palette; + png_bytep riffled_palette = png_ptr->riffled_palette; + png_const_bytep trans_alpha = png_ptr->trans_alpha; + int num_trans = png_ptr->num_trans; + int i; + + /* Initially black, opaque. */ + uint8x16x4_t w = {{ + vdupq_n_u8(0x00), + vdupq_n_u8(0x00), + vdupq_n_u8(0x00), + vdupq_n_u8(0xff), + }}; + + if (row_info->bit_depth != 8) + { + png_error(png_ptr, "bit_depth must be 8 for png_riffle_palette_rgba"); + return; + } + + /* First, riffle the RGB colours into a RGBA palette, the A value is + * set to opaque for now. + */ + for (i = 0; i < (1 << row_info->bit_depth); i += 16) + { + uint8x16x3_t v = vld3q_u8((png_const_bytep)(palette + i)); + w.val[0] = v.val[0]; + w.val[1] = v.val[1]; + w.val[2] = v.val[2]; + vst4q_u8(riffled_palette + (i << 2), w); + } + + /* Fix up the missing transparency values. */ + for (i = 0; i < num_trans; i++) + riffled_palette[(i << 2) + 3] = trans_alpha[i]; +} + +/* Expands a palettized row into RGBA. */ +int +png_do_expand_palette_neon_rgba(png_structrp png_ptr, png_row_infop row_info, + png_const_bytep row, png_bytepp ssp, png_bytepp ddp) +{ + png_uint_32 row_width = row_info->width; + const png_uint_32 *riffled_palette = + (const png_uint_32 *)png_ptr->riffled_palette; + const png_int_32 pixels_per_chunk = 4; + int i; + + if (row_width < pixels_per_chunk) + return 0; + + /* This function originally gets the last byte of the output row. + * The NEON part writes forward from a given position, so we have + * to seek this back by 4 pixels x 4 bytes. + */ + *ddp = *ddp - ((pixels_per_chunk * sizeof(png_uint_32)) - 1); + + for (i = 0; i < row_width; i += pixels_per_chunk) + { + uint32x4_t cur; + png_bytep sp = *ssp - i, dp = *ddp - (i << 2); + cur = vld1q_dup_u32 (riffled_palette + *(sp - 3)); + cur = vld1q_lane_u32(riffled_palette + *(sp - 2), cur, 1); + cur = vld1q_lane_u32(riffled_palette + *(sp - 1), cur, 2); + cur = vld1q_lane_u32(riffled_palette + *(sp - 0), cur, 3); + vst1q_u32((void *)dp, cur); + } + if (i != row_width) + { + /* Remove the amount that wasn't processed. */ + i -= pixels_per_chunk; + } + + /* Decrement output pointers. */ + *ssp = *ssp - i; + *ddp = *ddp - (i << 2); + return i; +} + +/* Expands a palettized row into RGB format. */ +int +png_do_expand_palette_neon_rgb(png_structrp png_ptr, png_row_infop row_info, + png_const_bytep row, png_bytepp ssp, png_bytepp ddp) +{ + png_uint_32 row_width = row_info->width; + png_const_bytep palette = (png_const_bytep)png_ptr->palette; + const png_uint_32 pixels_per_chunk = 8; + int i; + + if (row_width <= pixels_per_chunk) + return 0; + + /* Seeking this back by 8 pixels x 3 bytes. */ + *ddp = *ddp - ((pixels_per_chunk * sizeof(png_color)) - 1); + + for (i = 0; i < row_width; i += pixels_per_chunk) + { + uint8x8x3_t cur; + png_bytep sp = *ssp - i, dp = *ddp - ((i << 1) + i); + cur = vld3_dup_u8(palette + sizeof(png_color) * (*(sp - 7))); + cur = vld3_lane_u8(palette + sizeof(png_color) * (*(sp - 6)), cur, 1); + cur = vld3_lane_u8(palette + sizeof(png_color) * (*(sp - 5)), cur, 2); + cur = vld3_lane_u8(palette + sizeof(png_color) * (*(sp - 4)), cur, 3); + cur = vld3_lane_u8(palette + sizeof(png_color) * (*(sp - 3)), cur, 4); + cur = vld3_lane_u8(palette + sizeof(png_color) * (*(sp - 2)), cur, 5); + cur = vld3_lane_u8(palette + sizeof(png_color) * (*(sp - 1)), cur, 6); + cur = vld3_lane_u8(palette + sizeof(png_color) * (*(sp - 0)), cur, 7); + vst3_u8((void *)dp, cur); + } + + if (i != row_width) + { + /* Remove the amount that wasn't processed. */ + i -= pixels_per_chunk; + } + + /* Decrement output pointers. */ + *ssp = *ssp - i; + *ddp = *ddp - ((i << 1) + i); + return i; +} + +#endif /* PNG_ARM_NEON_IMPLEMENTATION */ |