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Code Issues Releases Wiki Activity

Fix summary values for edge cases when overall signal does not straddle zero line.

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martynshaw99 2012-05-05 20:57:50 +00:00
parent f98809817d
commit 2268f6f1e9
1 changed files with 8 additions and 8 deletions
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16
src/BlockFile.cpp
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@ -245,9 +245,10 @@ void *BlockFile::CalcSummary(samplePtr buffer, sampleCount len,
summary256[i * 3 + 2] = rms; summary256[i * 3 + 2] = rms;
} }
for (i = sumLen; i < mSummaryInfo.frames256; i++) { for (i = sumLen; i < mSummaryInfo.frames256; i++) {
summary256[i * 3] = 0.0f; // filling in the remaining bits with non-harming/contributing values
summary256[i * 3 + 1] = 0.0f; summary256[i * 3] = FLT_MAX; // min
summary256[i * 3 + 2] = 0.0f; summary256[i * 3 + 1] = -FLT_MAX; // max
summary256[i * 3 + 2] = 0.0f; // rms
} }
// Recalc 64K summaries // Recalc 64K summaries
@ -258,8 +259,7 @@ void *BlockFile::CalcSummary(samplePtr buffer, sampleCount len,
max = summary256[3 * i * 256 + 1]; max = summary256[3 * i * 256 + 1];
sumsq = (float)summary256[3 * i * 256 + 2]; sumsq = (float)summary256[3 * i * 256 + 2];
sumsq *= sumsq; sumsq *= sumsq;
for (j = 1; j < 256; j++) { // we can overflow the useful summary256 values here, but have put non-harmful values in them
for (j = 1; j < 256; j++) {
if (summary256[3 * (i * 256 + j)] < min) if (summary256[3 * (i * 256 + j)] < min)
min = summary256[3 * (i * 256 + j)]; min = summary256[3 * (i * 256 + j)];
if (summary256[3 * (i * 256 + j) + 1] > max) if (summary256[3 * (i * 256 + j) + 1] > max)
@ -268,15 +268,15 @@ void *BlockFile::CalcSummary(samplePtr buffer, sampleCount len,
sumsq += r1*r1; sumsq += r1*r1;
} }
float rms = (float)sqrt(sumsq / 256); float rms = (float)sqrt(sumsq / 256); // the '256' is not quite right at the edges as not all summary256 entries will be filled with useful values
summary64K[i * 3] = min; summary64K[i * 3] = min;
summary64K[i * 3 + 1] = max; summary64K[i * 3 + 1] = max;
summary64K[i * 3 + 2] = rms; summary64K[i * 3 + 2] = rms;
} }
for (i = sumLen; i < mSummaryInfo.frames64K; i++) { for (i = sumLen; i < mSummaryInfo.frames64K; i++) {
summary64K[i * 3] = 0.0f; summary64K[i * 3] = 0.0f; // probably should be FLT_MAX, need a test case
summary64K[i * 3 + 1] = 0.0f; summary64K[i * 3 + 1] = 0.0f; // probably should be -FLT_MAX, need a test case
summary64K[i * 3 + 2] = 0.0f; summary64K[i * 3 + 2] = 0.0f;
} }