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Special-case sparse transform

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If the number of non-zero coeffs is <= 3, use a
simplified transform for luma.

Change-Id: I78a1252704228d21720d4bc1221252c84338d9c8
This commit is contained in:
skal
2013-10-08 22:05:38 +02:00
parent 00125196f3
commit f9bbc2a034
6 changed files with 159 additions and 72 deletions
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36
src/dec/vp8.c
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@ -509,8 +509,8 @@ static int ParseResiduals(VP8Decoder* const dec,
int16_t* dst = block->coeffs_;
VP8MB* const left_mb = dec->mb_info_ - 1;
uint8_t tnz, lnz;
uint32_t non_zero_ac = 0;
uint32_t non_zero_dc = 0;
uint32_t non_zero_y = 0;
uint32_t non_zero_uv = 0;
int x, y, ch;
uint32_t out_t_nz, out_l_nz;
int first;
@ -539,26 +539,27 @@ static int ParseResiduals(VP8Decoder* const dec,
lnz = left_mb->nz_ & 0x0f;
for (y = 0; y < 4; ++y) {
int l = lnz & 1;
uint32_t nz_dc = 0, nz_ac = 0;
uint32_t nz_coeffs = 0;
for (x = 0; x < 4; ++x) {
const int ctx = l + (tnz & 1);
const int nz = GetCoeffs(token_br, ac_proba, ctx, q->y1_mat_, first, dst);
l = (nz > first);
tnz = (tnz >> 1) | (l << 7);
nz_dc = (nz_dc << 1) | (dst[0] != 0);
nz_ac = (nz_ac << 1) | (nz > 1);
nz_coeffs <<= 2;
if (nz > 3) nz_coeffs |= 3;
else if (nz > 1) nz_coeffs |= 2;
else if (dst[0] != 0) nz_coeffs |= 1;
dst += 16;
}
tnz >>= 4;
lnz = (lnz >> 1) | (l << 7);
non_zero_dc = (non_zero_dc << 4) | nz_dc;
non_zero_ac = (non_zero_ac << 4) | nz_ac;
non_zero_y = (non_zero_y << 8) | nz_coeffs;
}
out_t_nz = tnz;
out_l_nz = lnz >> 4;
for (ch = 0; ch < 4; ch += 2) {
uint32_t nz_dc = 0, nz_ac = 0;
uint32_t nz_coeffs = 0;
tnz = mb->nz_ >> (4 + ch);
lnz = left_mb->nz_ >> (4 + ch);
for (y = 0; y < 2; ++y) {
@ -568,25 +569,26 @@ static int ParseResiduals(VP8Decoder* const dec,
const int nz = GetCoeffs(token_br, bands[2], ctx, q->uv_mat_, 0, dst);
l = (nz > 0);
tnz = (tnz >> 1) | (l << 3);
nz_dc = (nz_dc << 1) | (dst[0] != 0);
nz_ac = (nz_ac << 1) | (nz > 1);
nz_coeffs <<= 2;
if (nz > 3) nz_coeffs |= 3;
else if (nz > 1) nz_coeffs |= 2;
else if (dst[0] != 0) nz_coeffs |= 1;
dst += 16;
}
tnz >>= 2;
lnz = (lnz >> 1) | (l << 5);
}
// Note: we don't really need the per-4x4 details for U/V blocks.
non_zero_dc |= (nz_dc & 0x0f) << (16 + 2 * ch);
non_zero_ac |= (nz_ac & 0x0f) << (16 + 2 * ch);
non_zero_uv |= nz_coeffs << (4 * ch);
out_t_nz |= (tnz << 4) << ch;
out_l_nz |= (lnz & 0xf0) << ch;
}
mb->nz_ = out_t_nz;
left_mb->nz_ = out_l_nz;
block->non_zero_ac_ = non_zero_ac;
block->non_zero_ = non_zero_ac | non_zero_dc;
return !block->non_zero_; // will be used for further optimization
block->non_zero_y_ = non_zero_y;
block->non_zero_uv_ = non_zero_uv;
return !(non_zero_y | non_zero_uv); // will be used for further optimization
}
//------------------------------------------------------------------------------
@ -621,8 +623,8 @@ int VP8DecodeMB(VP8Decoder* const dec, VP8BitReader* const token_br) {
if (!block->is_i4x4_) {
left->nz_dc_ = mb->nz_dc_ = 0;
}
block->non_zero_ = 0;
block->non_zero_ac_ = 0;
block->non_zero_y_ = 0;
block->non_zero_uv_ = 0;
}
if (dec->filter_type_ > 0) { // store filter info