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frame: Use copy when possible

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This commit is contained in:
Hajime Hoshi 2017-12-31 00:51:00 +09:00
parent 3bda0e6aa0
commit b43def0c64
1 changed files with 6 additions and 11 deletions
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17
internal/frame/frame.go
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@ -265,9 +265,8 @@ func (f *Frame) reorder(gr int, ch int) {
// Check if we're into the next scalefac band
if i == next_sfb {
// Copy reordered data back to the original vector
for j := 0; j < 3*win_len; j++ {
f.mainData.Is[gr][ch][3*consts.SfBandIndicesSet[sfreq].S[sfb]+j] = re[j]
}
j := 3 * consts.SfBandIndicesSet[sfreq].S[sfb]
copy(f.mainData.Is[gr][ch][j:j+win_len], re[0:3*win_len])
// Check if this band is above the rzero region,if so we're done
if i >= f.sideInfo.Count1[gr][ch] {
return
@ -284,9 +283,8 @@ func (f *Frame) reorder(gr int, ch int) {
}
}
// Copy reordered data of last band back to original vector
for j := 0; j < 3*win_len; j++ {
f.mainData.Is[gr][ch][3*consts.SfBandIndicesSet[sfreq].S[12]+j] = re[j]
}
j := 3 * consts.SfBandIndicesSet[sfreq].S[12]
copy(f.mainData.Is[gr][ch][j:j+3*win_len], re[0:3*win_len])
}
}
@ -298,8 +296,7 @@ func (f *Frame) stereoProcessIntensityLong(gr int, sfb int) {
is_ratio_l := float32(0)
is_ratio_r := float32(0)
// Check that((is_pos[sfb]=scalefac) != 7) => no intensity stereo
is_pos := f.mainData.ScalefacL[gr][0][sfb]
if is_pos != 7 {
if is_pos := f.mainData.ScalefacL[gr][0][sfb]; is_pos != 7 {
sfreq := f.header.SamplingFrequency() // Setup sampling freq index
sfb_start := consts.SfBandIndicesSet[sfreq].L[sfb]
sfb_stop := consts.SfBandIndicesSet[sfreq].L[sfb+1]
@ -623,9 +620,7 @@ func (f *Frame) subbandSynthesis(gr int, ch int, out []byte) {
nch := f.header.NumberOfChannels()
// Setup the n_win windowing vector and the v_vec intermediate vector
for ss := 0; ss < 18; ss++ { // Loop through 18 samples in 32 subbands
for i := 1023; i > 63; i-- { // Shift up the V vector
f.v_vec[ch][i] = f.v_vec[ch][i-64]
}
copy(f.v_vec[ch][64:1024], f.v_vec[ch][0:1024-64])
for i := 0; i < 32; i++ { // Copy next 32 time samples to a temp vector
s_vec[i] = f.mainData.Is[gr][ch][i*18+ss]
}