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Less memory copy in Clock Recovery MM

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This commit is contained in:
Aang23 2021-10-22 19:18:13 +02:00
parent 3c4019cb2b
commit 9da3205bb5
1 changed files with 17 additions and 9 deletions
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26
src-core/common/dsp/clock_recovery_mm.cpp
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@ -46,13 +46,13 @@ namespace dsp
return;
}
memcpy(&buffer[in_buffer], input_stream->readBuf, nsamples * sizeof(complex_t));
in_buffer += nsamples;
// Copy NTAPS samples in the buffer from input, as that's required for the last samples
memcpy(&buffer[in_buffer], input_stream->readBuf, NTAPS * sizeof(complex_t));
int out_c = 0; // Output index
int in_c = 0; // Input index
int input_number = in_buffer - NTAPS - 16; // Number of samples to use
float phase_error = 0; // Phase Error
int out_c = 0; // Output index
int in_c = 0; // Input index
int input_number = (in_buffer + nsamples) - NTAPS - 16; // Number of samples to use
float phase_error = 0; // Phase Error
for (; in_c < input_number;)
{
@ -68,7 +68,11 @@ namespace dsp
imu = 0;
if (imu > NSTEPS)
imu = NSTEPS;
volk_32fc_32f_dot_prod_32fc((lv_32fc_t *)&p_0T, (lv_32fc_t *)&buffer[in_c], TAPS[imu], NTAPS);
if (in_c < in_buffer)
volk_32fc_32f_dot_prod_32fc((lv_32fc_t *)&p_0T, (lv_32fc_t *)&buffer[in_c], TAPS[imu], NTAPS);
else
volk_32fc_32f_dot_prod_32fc((lv_32fc_t *)&p_0T, (lv_32fc_t *)&input_stream->readBuf[in_c - in_buffer], TAPS[imu], NTAPS);
// Slice it
c_0T = complex_t(p_0T.real > 0.0f ? 1.0f : 0.0f, p_0T.imag > 0.0f ? 1.0f : 0.0f);
@ -92,8 +96,12 @@ namespace dsp
in_c = 0;
}
memmove(&buffer[0], &buffer[in_c], (in_buffer - in_c) * sizeof(complex_t));
in_buffer -= in_c;
// We need some history for the next run, so copy it over into our buffer
// If everything's normal this will be around NTAPS - 16 +-1, but the buffer
// is way larger just by safety
int to_keep = nsamples - (in_c - in_buffer);
memcpy(&buffer[0], &input_stream->readBuf[in_c - in_buffer], to_keep * sizeof(complex_t));
in_buffer = to_keep;
input_stream->flush();
output_stream->swap(out_c);