// Copyright 2018 Google Inc. All Rights Reserved. // // Use of this source code is governed by a BSD-style license // that can be found in the COPYING file in the root of the source // tree. An additional intellectual property rights grant can be found // in the file PATENTS. All contributing project authors may // be found in the AUTHORS file in the root of the source tree. // ----------------------------------------------------------------------------- #ifndef WEBP_DSP_QUANT_H_ #define WEBP_DSP_QUANT_H_ #include <string.h> #include "dsp_dsp.h" #include "webp_types.h" #if defined(WEBP_USE_NEON) && !defined(WEBP_ANDROID_NEON) && \ !defined(WEBP_HAVE_NEON_RTCD) #include <arm_neon.h> #define IsFlat IsFlat_NEON static uint32x2_t horizontal_add_uint32x4(const uint32x4_t a) { const uint64x2_t b = vpaddlq_u32(a); return vadd_u32(vreinterpret_u32_u64(vget_low_u64(b)), vreinterpret_u32_u64(vget_high_u64(b))); } static WEBP_INLINE int IsFlat(const int16_t* levels, int num_blocks, int thresh) { const int16x8_t tst_ones = vdupq_n_s16(-1); uint32x4_t sum = vdupq_n_u32(0); for (int i = 0; i < num_blocks; ++i) { // Set DC to zero. const int16x8_t a_0 = vsetq_lane_s16(0, vld1q_s16(levels), 0); const int16x8_t a_1 = vld1q_s16(levels + 8); const uint16x8_t b_0 = vshrq_n_u16(vtstq_s16(a_0, tst_ones), 15); const uint16x8_t b_1 = vshrq_n_u16(vtstq_s16(a_1, tst_ones), 15); sum = vpadalq_u16(sum, b_0); sum = vpadalq_u16(sum, b_1); levels += 16; } return thresh >= (int32_t)vget_lane_u32(horizontal_add_uint32x4(sum), 0); } #else #define IsFlat IsFlat_C static WEBP_INLINE int IsFlat(const int16_t* levels, int num_blocks, int thresh) { int score = 0; while (num_blocks-- > 0) { // TODO(skal): refine positional scoring? int i; for (i = 1; i < 16; ++i) { // omit DC, we're only interested in AC score += (levels[i] != 0); if (score > thresh) return 0; } levels += 16; } return 1; } #endif // defined(WEBP_USE_NEON) && !defined(WEBP_ANDROID_NEON) && // !defined(WEBP_HAVE_NEON_RTCD) static WEBP_INLINE int IsFlatSource16(const uint8_t* src) { const uint32_t v = src[0] * 0x01010101u; int i; for (i = 0; i < 16; ++i) { if (memcmp(src + 0, &v, 4) || memcmp(src + 4, &v, 4) || memcmp(src + 8, &v, 4) || memcmp(src + 12, &v, 4)) { return 0; } src += BPS; } return 1; } #endif // WEBP_DSP_QUANT_H_