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Diffstat (limited to 'media/libwebp/src/dsp/quant.h')
-rw-r--r-- | media/libwebp/src/dsp/quant.h | 90 |
1 files changed, 90 insertions, 0 deletions
diff --git a/media/libwebp/src/dsp/quant.h b/media/libwebp/src/dsp/quant.h new file mode 100644 index 0000000000..fc099bf9d6 --- /dev/null +++ b/media/libwebp/src/dsp/quant.h @@ -0,0 +1,90 @@ +// 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 "src/dsp/dsp.h" +#include "src/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 uint32_t horizontal_add_uint32x4(const uint32x4_t a) { +#if defined(__aarch64__) + return vaddvq_u32(a); +#else + const uint64x2_t b = vpaddlq_u32(a); + const uint32x2_t c = vadd_u32(vreinterpret_u32_u64(vget_low_u64(b)), + vreinterpret_u32_u64(vget_high_u64(b))); + return vget_lane_u32(c, 0); +#endif +} + +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 >= (int)horizontal_add_uint32x4(sum); +} + +#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_ |