satdump/src-core/common/codings/differential/generic.cpp
2021-05-21 23:07:07 +02:00

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642 B
C++

#include "generic.h"
namespace diff
{
GenericDiff::GenericDiff(unsigned int modulus) : d_modulus(modulus)
{
}
int GenericDiff::work(uint8_t *in, int length, uint8_t *out)
{
tmp_.insert(tmp_.end(), in, &in[length]);
uint8_t *input = &tmp_[1]; // ensure that input[-1] is valid
unsigned modulus = d_modulus;
for (int i = 0; i < (int)tmp_.size() - 2; i++)
{
out[i] = (input[i] - input[i - 1]) % modulus;
}
int out_size = tmp_.size() - 2;
tmp_.erase(tmp_.begin(), tmp_.end() - 2); // History
return out_size;
}
} // namespace diff