dany/libwebp
1
0
Fork 0
mirror of https://github.com/webmproject/libwebp.git synced 2024-12-25 13:18:22 +01:00
Code Issues Actions Packages Projects Releases Wiki Activity

simplify the fwd transform

Browse Source 
-> remove two shifts

Change-Id: Ibc55bca98588da30553a7870224ffd0e13d57f52
This commit is contained in:
skal 2012-11-15 09:51:35 +01:00
parent b542611964
commit 42c3b550ba
3 changed files with 60 additions and 60 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

22
src/dsp/enc.c
View File

@ -134,25 +134,25 @@ static void FTransform(const uint8_t* src, const uint8_t* ref, int16_t* out) {
int i;
int tmp[16];
for (i = 0; i < 4; ++i, src += BPS, ref += BPS) {
const int d0 = src[0] - ref[0];
const int d0 = src[0] - ref[0]; // 9bit dynamic range ([-255,255])
const int d1 = src[1] - ref[1];
const int d2 = src[2] - ref[2];
const int d3 = src[3] - ref[3];
const int a0 = (d0 + d3) << 3;
const int a1 = (d1 + d2) << 3;
const int a2 = (d1 - d2) << 3;
const int a3 = (d0 - d3) << 3;
tmp[0 + i * 4] = (a0 + a1);
tmp[1 + i * 4] = (a2 * 2217 + a3 * 5352 + 14500) >> 12;
tmp[2 + i * 4] = (a0 - a1);
tmp[3 + i * 4] = (a3 * 2217 - a2 * 5352 + 7500) >> 12;
const int a0 = (d0 + d3); // 10b [-510,510]
const int a1 = (d1 + d2);
const int a2 = (d1 - d2);
const int a3 = (d0 - d3);
tmp[0 + i * 4] = (a0 + a1) << 3; // 14b [-8160,8160]
tmp[1 + i * 4] = (a2 * 2217 + a3 * 5352 + 1812) >> 9; // [-7536,7542]
tmp[2 + i * 4] = (a0 - a1) << 3;
tmp[3 + i * 4] = (a3 * 2217 - a2 * 5352 + 937) >> 9;
}
for (i = 0; i < 4; ++i) {
const int a0 = (tmp[0 + i] + tmp[12 + i]);
const int a0 = (tmp[0 + i] + tmp[12 + i]); // 15b
const int a1 = (tmp[4 + i] + tmp[ 8 + i]);
const int a2 = (tmp[4 + i] - tmp[ 8 + i]);
const int a3 = (tmp[0 + i] - tmp[12 + i]);
out[0 + i] = (a0 + a1 + 7) >> 4;
out[0 + i] = (a0 + a1 + 7) >> 4; // 12b
out[4 + i] = ((a2 * 2217 + a3 * 5352 + 12000) >> 16) + (a3 != 0);
out[8 + i] = (a0 - a1 + 7) >> 4;
out[12+ i] = ((a3 * 2217 - a2 * 5352 + 51000) >> 16);

46
src/dsp/enc_neon.c
View File

@ -222,15 +222,15 @@ static const int16_t kCoeff16[] = {
5352, 5352, 5352, 5352, 2217, 2217, 2217, 2217
};
static const int32_t kCoeff32[] = {
14500, 14500, 14500, 14500,
7500, 7500, 7500, 7500,
1812, 1812, 1812, 1812,
937, 937, 937, 937,
12000, 12000, 12000, 12000,
51000, 51000, 51000, 51000
};
static void FTransform(const uint8_t* src, const uint8_t* ref,
int16_t* out) {
const int kBPS = BPS;
const int kBPS = BPS;
const uint8_t* src_ptr = src;
const uint8_t* ref_ptr = ref;
int16_t* coeff16 = kCoeff16;
@ -253,45 +253,45 @@ static void FTransform(const uint8_t* src, const uint8_t* ref,
"vtrn.32 q4, q5 \n"
"vtrn.32 q6, q7 \n"
// {q0, q1} = q4 - q6
// d[0-3] = src - ref
"vsubl.u8 q0, d8, d12 \n"
"vsubl.u8 q1, d9, d13 \n"
// load coeff16 into q8(d16=5352, d17=2217)
"vld1.16 {q8}, [%[coeff16]] \n"
// load coeff32 high half into q9 = 14500, q10 = 7500
// load coeff32 high half into q9 = 1812, q10 = 937
"vld1.32 {q9, q10}, [%[coeff32]]! \n"
// load coeff32 low half into q11=12000, q12=51000
"vld1.32 {q11,q12}, [%[coeff32]] \n"
// part 1
// transpose d0=ip[0], d1=ip[1], d2=ip[2], d3=ip[3]
// Transpose. Register dN is the same as dN in C
"vtrn.32 d0, d2 \n"
"vtrn.32 d1, d3 \n"
"vtrn.16 d0, d1 \n"
"vtrn.16 d2, d3 \n"
"vadd.s16 d4, d0, d3 \n" // a1 = ip[0] + ip[3]
"vadd.s16 d5, d1, d2 \n" // b1 = ip[1] + ip[2]
"vsub.s16 d6, d1, d2 \n" // c1 = ip[1] - ip[2]
"vsub.s16 d7, d0, d3 \n" // d1 = ip[0] - ip[3]
"vadd.s16 d4, d0, d3 \n" // a0 = d0 + d3
"vadd.s16 d5, d1, d2 \n" // a1 = d1 + d2
"vsub.s16 d6, d1, d2 \n" // a2 = d1 - d2
"vsub.s16 d7, d0, d3 \n" // a3 = d0 - d3
"vshl.s16 q2, q2, #3 \n" // (a1, b1) << 3
"vshl.s16 q3, q3, #3 \n" // (c1, d1) << 3
"vadd.s16 d0, d4, d5 \n" // a0 + a1
"vshl.s16 d0, d0, #3 \n" // temp[0+i*4] = (a0+a1) << 3
"vsub.s16 d2, d4, d5 \n" // a0 - a1
"vshl.s16 d2, d2, #3 \n" // (temp[2+i*4] = (a0-a1) << 3
"vadd.s16 d0, d4, d5 \n" // op[0] = a1 + b1
"vsub.s16 d2, d4, d5 \n" // op[2] = a1 - b1
"vmlal.s16 q9, d7, d16 \n" // d1*5352 + 14500
"vmlal.s16 q10, d7, d17 \n" // d1*2217 + 7500
"vmlal.s16 q9, d6, d17 \n" // c1*2217 + d1*5352 + 14500
"vmlsl.s16 q10, d6, d16 \n" // d1*2217 - c1*5352 + 7500
"vmlal.s16 q9, d7, d16 \n" // a3*5352 + 1812
"vmlal.s16 q10, d7, d17 \n" // a3*2217 + 937
"vmlal.s16 q9, d6, d17 \n" // a2*2217 + a3*5352 + 1812
"vmlsl.s16 q10, d6, d16 \n" // a3*2217 + 937 - a2*5352
// op[1] = (c1*2217 + d1*5352 + 14500) >> 12
// op[3] = (d1*2217 - c1*5352 + 7500) >> 12
"vshrn.s32 d1, q9, #12 \n"
"vshrn.s32 d3, q10, #12 \n"
// temp[1+i*4] = (d2*2217 + d3*5352 + 1812) >> 9
// temp[3+i*4] = (d3*2217 + 937 - d2*5352) >> 9
"vshrn.s32 d1, q9, #9 \n"
"vshrn.s32 d3, q10, #9 \n"
// part 2
// transpose d0=ip[0], d1=ip[4], d2=ip[8], d3=ip[12]
@ -398,7 +398,7 @@ static void FTransformWHT(const int16_t* in, int16_t* out) {
"vqsub.s32 q6, q3, q2 \n" // b2 = a3 - a2
"vqsub.s32 q7, q0, q1 \n" // b3 = a0 - a1
"vmov.32 q0, #3 \n" // q0 = 3
"vmov.s32 q0, #3 \n" // q0 = 3
"vcgt.s32 q1, q4, #0 \n" // (b0>0)
"vqsub.s32 q2, q4, q1 \n" // (b0+(b0>0))

52
src/dsp/enc_sse2.c
View File

@ -295,8 +295,8 @@ static void FTransformSSE2(const uint8_t* src, const uint8_t* ref,
int16_t* out) {
const __m128i zero = _mm_setzero_si128();
const __m128i seven = _mm_set1_epi16(7);
const __m128i k7500 = _mm_set1_epi32(7500);
const __m128i k14500 = _mm_set1_epi32(14500);
const __m128i k937 = _mm_set1_epi32(937);
const __m128i k1812 = _mm_set1_epi32(1812);
const __m128i k51000 = _mm_set1_epi32(51000);
const __m128i k12000_plus_one = _mm_set1_epi32(12000 + (1 << 16));
const __m128i k5352_2217 = _mm_set_epi16(5352, 2217, 5352, 2217,
@ -352,32 +352,32 @@ static void FTransformSSE2(const uint8_t* src, const uint8_t* ref,
// First pass and subsequent transpose.
{
// Same operations are done on the (0,3) and (1,2) pairs.
// b0 = (a0 + a3) << 3
// b1 = (a1 + a2) << 3
// b3 = (a0 - a3) << 3
// b2 = (a1 - a2) << 3
// b0 = (a0 + a3)
// b1 = (a1 + a2)
// b3 = (a0 - a3)
// b2 = (a1 - a2)
const __m128i a01 = _mm_add_epi16(v01, v32);
const __m128i a32 = _mm_sub_epi16(v01, v32);
const __m128i b01 = _mm_slli_epi16(a01, 3);
const __m128i b32 = _mm_slli_epi16(a32, 3);
const __m128i b11 = _mm_unpackhi_epi64(b01, b01);
const __m128i b22 = _mm_unpackhi_epi64(b32, b32);
const __m128i b11 = _mm_unpackhi_epi64(a01, a01);
const __m128i b22 = _mm_unpackhi_epi64(a32, a32);
// e0 = b0 + b1
// e2 = b0 - b1
const __m128i e0 = _mm_add_epi16(b01, b11);
const __m128i e2 = _mm_sub_epi16(b01, b11);
const __m128i e02 = _mm_unpacklo_epi64(e0, e2);
// e0 = (b0 + b1)
// e2 = (b0 - b1)
const __m128i e0 = _mm_add_epi16(a01, b11);
const __m128i e2 = _mm_sub_epi16(a01, b11);
// e02 = [e0 | e2] << 3
const __m128i e0_e2 = _mm_unpacklo_epi64(e0, e2);
const __m128i e02 = _mm_slli_epi16(e0_e2, 3);
// e1 = (b3 * 5352 + b2 * 2217 + 14500) >> 12
// e3 = (b3 * 2217 - b2 * 5352 + 7500) >> 12
const __m128i b23 = _mm_unpacklo_epi16(b22, b32);
// e1 = (b3 * 5352 + b2 * 2217 + 1812) >> 9
// e3 = (b3 * 2217 - b2 * 5352 + 937) >> 9
const __m128i b23 = _mm_unpacklo_epi16(b22, a32);
const __m128i c1 = _mm_madd_epi16(b23, k5352_2217);
const __m128i c3 = _mm_madd_epi16(b23, k2217_5352);
const __m128i d1 = _mm_add_epi32(c1, k14500);
const __m128i d3 = _mm_add_epi32(c3, k7500);
const __m128i e1 = _mm_srai_epi32(d1, 12);
const __m128i e3 = _mm_srai_epi32(d3, 12);
const __m128i d1 = _mm_add_epi32(c1, k1812);
const __m128i d3 = _mm_add_epi32(c3, k937);
const __m128i e1 = _mm_srai_epi32(d1, 9);
const __m128i e3 = _mm_srai_epi32(d3, 9);
const __m128i e13 = _mm_packs_epi32(e1, e3);
// Transpose.
@ -406,13 +406,12 @@ static void FTransformSSE2(const uint8_t* src, const uint8_t* ref,
const __m128i a32 = _mm_sub_epi16(v01, v32);
const __m128i a11 = _mm_unpackhi_epi64(a01, a01);
const __m128i a22 = _mm_unpackhi_epi64(a32, a32);
const __m128i a01_plus_7 = _mm_add_epi16(a01, seven);
// d0 = (a0 + a1 + 7) >> 4;
// d2 = (a0 - a1 + 7) >> 4;
const __m128i b0 = _mm_add_epi16(a01, a11);
const __m128i b2 = _mm_sub_epi16(a01, a11);
const __m128i c0 = _mm_add_epi16(b0, seven);
const __m128i c2 = _mm_add_epi16(b2, seven);
const __m128i c0 = _mm_add_epi16(a01_plus_7, a11);
const __m128i c2 = _mm_sub_epi16(a01_plus_7, a11);
const __m128i d0 = _mm_srai_epi16(c0, 4);
const __m128i d2 = _mm_srai_epi16(c2, 4);
@ -430,6 +429,7 @@ static void FTransformSSE2(const uint8_t* src, const uint8_t* ref,
// f1 = f1 + (a3 != 0);
// The compare will return (0xffff, 0) for (==0, !=0). To turn that into the
// desired (0, 1), we add one earlier through k12000_plus_one.
// -> f1 = f1 + 1 - (a3 == 0)
const __m128i g1 = _mm_add_epi16(f1, _mm_cmpeq_epi16(a32, zero));
_mm_storel_epi64((__m128i*)&out[ 0], d0);