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NEON functions for lossless coding

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Verified OK, but right now they don't seem faster.
So they are disabled behind a USE_INTRINSICS flag (off for now)

Change-Id: I72a1c4fa3798f98c1e034f7ca781914c36d3392c
This commit is contained in:
skal 2014-04-09 18:40:02 +02:00
parent 3fe0291530
commit 3d49871dbe
1 changed files with 190 additions and 0 deletions
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190
src/dsp/lossless_neon.c
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@ -19,6 +19,10 @@
#include "./lossless.h"
// Right now, some intrinsics function seem slower, so we disable it.
// Uncomment the following for testing:
// #define USE_INTRINSICS
//------------------------------------------------------------------------------
// Colorspace conversion functions
@ -140,6 +144,176 @@ static void ConvertBGRAToRGB(const uint32_t* src,
#endif // gcc-4.8
//------------------------------------------------------------------------------
#ifdef USE_INTRINSICS
static WEBP_INLINE uint32_t Average2(const uint32_t* const a,
const uint32_t* const b) {
const uint64x1_t a0 = { *a }, b0 = { *b };
const uint8x8_t a1 = vreinterpret_u8_u64(a0);
const uint8x8_t b1 = vreinterpret_u8_u64(b0);
const uint8x8_t avg = vhadd_u8(a1, b1);
uint32_t ret;
vst1_lane_u32(&ret, vreinterpret_u32_u8(avg), 0);
return ret;
}
static WEBP_INLINE uint32_t Average3(const uint32_t* const a,
const uint32_t* const b,
const uint32_t* const c) {
const uint64x1_t a0 = { *a }, b0 = { *b }, c0 = { *c };
const uint8x8_t a1 = vreinterpret_u8_u64(a0);
const uint8x8_t b1 = vreinterpret_u8_u64(b0);
const uint8x8_t c1 = vreinterpret_u8_u64(c0);
const uint8x8_t avg1 = vhadd_u8(a1, c1);
const uint8x8_t avg2 = vhadd_u8(avg1, b1);
uint32_t ret;
vst1_lane_u32(&ret, vreinterpret_u32_u8(avg2), 0);
return ret;
}
static WEBP_INLINE uint32_t Average4(const uint32_t* const a,
const uint32_t* const b,
const uint32_t* const c,
const uint32_t* const d) {
const uint64x1_t a0 = { *a }, b0 = { *b }, c0 = { *c }, d0 = { *d };
const uint8x8_t a1 = vreinterpret_u8_u64(a0);
const uint8x8_t b1 = vreinterpret_u8_u64(b0);
const uint8x8_t c1 = vreinterpret_u8_u64(c0);
const uint8x8_t d1 = vreinterpret_u8_u64(d0);
const uint8x8_t avg1 = vhadd_u8(a1, b1);
const uint8x8_t avg2 = vhadd_u8(c1, d1);
const uint8x8_t avg3 = vhadd_u8(avg1, avg2);
uint32_t ret;
vst1_lane_u32(&ret, vreinterpret_u32_u8(avg3), 0);
return ret;
}
static uint32_t Predictor5(uint32_t left, const uint32_t* const top) {
return Average3(&left, top + 0, top + 1);
}
static uint32_t Predictor6(uint32_t left, const uint32_t* const top) {
return Average2(&left, top - 1);
}
static uint32_t Predictor7(uint32_t left, const uint32_t* const top) {
return Average2(&left, top + 0);
}
static uint32_t Predictor8(uint32_t left, const uint32_t* const top) {
(void)left;
return Average2(top - 1, top + 0);
}
static uint32_t Predictor9(uint32_t left, const uint32_t* const top) {
(void)left;
return Average2(top + 0, top + 1);
}
static uint32_t Predictor10(uint32_t left, const uint32_t* const top) {
return Average4(&left, top - 1, top + 0, top + 1);
}
//------------------------------------------------------------------------------
static WEBP_INLINE uint32_t Select(const uint32_t* const c0,
const uint32_t* const c1,
const uint32_t* const c2) {
const uint64x1_t C0 = { *c0, 0 }, C1 = { *c1, 0 }, C2 = { *c2, 0 };
const uint8x8_t p0 = vreinterpret_u8_u64(C0);
const uint8x8_t p1 = vreinterpret_u8_u64(C1);
const uint8x8_t p2 = vreinterpret_u8_u64(C2);
const uint8x8_t bc = vabd_u8(p1, p2); // |b-c|
const uint8x8_t ac = vabd_u8(p0, p2); // |a-c|
const int16x4_t sum_bc = vreinterpret_s16_u16(vpaddl_u8(bc));
const int16x4_t sum_ac = vreinterpret_s16_u16(vpaddl_u8(ac));
const int32x2_t diff = vpaddl_s16(vsub_s16(sum_bc, sum_ac));
int32_t pa_minus_pb;
vst1_lane_s32(&pa_minus_pb, diff, 0);
return (pa_minus_pb <= 0) ? *c0 : *c1;
}
static uint32_t Predictor11(uint32_t left, const uint32_t* const top) {
return Select(top + 0, &left, top - 1);
}
static WEBP_INLINE uint32_t ClampedAddSubtractFull(const uint32_t* const c0,
const uint32_t* const c1,
const uint32_t* const c2) {
const uint64x1_t C0 = { *c0, 0 }, C1 = { *c1, 0 }, C2 = { *c2, 0 };
const uint8x8_t p0 = vreinterpret_u8_u64(C0);
const uint8x8_t p1 = vreinterpret_u8_u64(C1);
const uint8x8_t p2 = vreinterpret_u8_u64(C2);
const uint16x8_t sum0 = vaddl_u8(p0, p1); // add and widen
const uint16x8_t sum1 = vqsubq_u16(sum0, vmovl_u8(p2)); // widen and subtract
const uint8x8_t out = vqmovn_u16(sum1); // narrow and clamp
uint32_t ret;
vst1_lane_u32(&ret, vreinterpret_u32_u8(out), 0);
return ret;
}
static uint32_t Predictor12(uint32_t left, const uint32_t* const top) {
return ClampedAddSubtractFull(&left, top + 0, top - 1);
}
static WEBP_INLINE uint32_t ClampedAddSubtractHalf(const uint32_t* const c0,
const uint32_t* const c1,
const uint32_t* const c2) {
const uint64x1_t C0 = { *c0, 0 }, C1 = { *c1, 0 }, C2 = { *c2, 0 };
const uint8x8_t p0 = vreinterpret_u8_u64(C0);
const uint8x8_t p1 = vreinterpret_u8_u64(C1);
const uint8x8_t p2 = vreinterpret_u8_u64(C2);
const uint8x8_t avg = vhadd_u8(p0, p1); // Average(c0,c1)
const uint8x8_t ab = vshr_n_u8(vqsub_u8(avg, p2), 1); // (a-b)>>1 saturated
const uint8x8_t ba = vshr_n_u8(vqsub_u8(p2, avg), 1); // (b-a)>>1 saturated
const uint8x8_t out = vqsub_u8(vqadd_u8(avg, ab), ba);
uint32_t ret;
vst1_lane_u32(&ret, vreinterpret_u32_u8(out), 0);
return ret;
}
static uint32_t Predictor13(uint32_t left, const uint32_t* const top) {
return ClampedAddSubtractHalf(&left, top + 0, top - 1);
}
//------------------------------------------------------------------------------
// Subtract-Green Transform
// 255 = byte will be zero'd
static const uint8_t kGreenShuffle[8] = { 1, 255, 1, 255, 5, 255, 5, 255 };
static void SubtractGreenFromBlueAndRed(uint32_t* argb_data, int num_pixels) {
const uint32_t* const end = argb_data + (num_pixels & ~3);
const uint8x8_t shuffle = vld1_u8(kGreenShuffle);
for (; argb_data < end; argb_data += 4) {
const uint8x16_t argb = vld1q_u8((uint8_t*)argb_data);
const uint8x16_t greens =
vcombine_u8(vtbl1_u8(vget_low_u8(argb), shuffle),
vtbl1_u8(vget_high_u8(argb), shuffle));
vst1q_u8((uint8_t*)argb_data, vsubq_u8(argb, greens));
}
// fallthrough and finish off with plain-C
VP8LSubtractGreenFromBlueAndRed_C(argb_data, num_pixels & 3);
}
static void AddGreenToBlueAndRed(uint32_t* argb_data, int num_pixels) {
const uint32_t* const end = argb_data + (num_pixels & ~3);
const uint8x8_t shuffle = vld1_u8(kGreenShuffle);
for (; argb_data < end; argb_data += 4) {
const uint8x16_t argb = vld1q_u8((uint8_t*)argb_data);
const uint8x16_t greens =
vcombine_u8(vtbl1_u8(vget_low_u8(argb), shuffle),
vtbl1_u8(vget_high_u8(argb), shuffle));
vst1q_u8((uint8_t*)argb_data, vaddq_u8(argb, greens));
}
// fallthrough and finish off with plain-C
VP8LAddGreenToBlueAndRed_C(argb_data, num_pixels & 3);
}
#endif // USE_INTRINSICS
#endif // WEBP_USE_NEON
//------------------------------------------------------------------------------
@ -151,6 +325,22 @@ void VP8LDspInitNEON(void) {
VP8LConvertBGRAToRGBA = ConvertBGRAToRGBA;
VP8LConvertBGRAToBGR = ConvertBGRAToBGR;
VP8LConvertBGRAToRGB = ConvertBGRAToRGB;
#ifdef USE_INTRINSICS
VP8LPredictors[5] = Predictor5;
VP8LPredictors[6] = Predictor6;
VP8LPredictors[7] = Predictor7;
VP8LPredictors[8] = Predictor8;
VP8LPredictors[9] = Predictor9;
VP8LPredictors[10] = Predictor10;
VP8LPredictors[11] = Predictor11;
VP8LPredictors[12] = Predictor12;
VP8LPredictors[13] = Predictor13;
VP8LSubtractGreenFromBlueAndRed = SubtractGreenFromBlueAndRed;
VP8LAddGreenToBlueAndRed = AddGreenToBlueAndRed;
#endif
#endif // WEBP_USE_NEON
}