Lines Matching defs:energy
878 // Filter energy
894 // Measure energy in each filter partition to determine delay.
1116 // losing half the energy on the average. We take care of the first
1317 // Do the energy calculation in the frequency domain. The FFT is performed on
1318 // a segment of PART_LEN2 samples due to overlap, but we only want the energy
1320 // that the energy is preserved according to
1323 // = ENERGY,
1325 // where N = PART_LEN2. Since we are only interested in calculating the energy
1326 // for the last PART_LEN samples we approximate by calculating ENERGY and
1329 // \sum_{n=N/2}^{N-1} |x(n)|^2 ~= ENERGY / 2
1332 // bins [0, PART_LEN], which is what |in| consists of. To calculate ENERGY we
1339 // TODO(bjornv): Investigate reusing energy calculations performed at other
1343 float energy = (in[0][0] * in[0][0]) / 2;
1344 energy += (in[0][PART_LEN] * in[0][PART_LEN]) / 2;
1347 energy += (in[0][k] * in[0][k] + in[1][k] * in[1][k]);
1349 energy /= PART_LEN2;
1351 level->sfrsum += energy;
