Merge "Fix rounding in RecordThread resampler buffer computation" into lmp-dev
diff --git a/services/audioflinger/Threads.cpp b/services/audioflinger/Threads.cpp
index c959b9f..0ef5bb8 100644
--- a/services/audioflinger/Threads.cpp
+++ b/services/audioflinger/Threads.cpp
@@ -5297,11 +5297,13 @@
// to keep mRsmpInBuffer full so resampler always has sufficient input
size_t framesInNeeded;
// FIXME only re-calculate when it changes, and optimize for common ratios
- double inOverOut = (double) mSampleRate / activeTrack->mSampleRate;
- double outOverIn = (double) activeTrack->mSampleRate / mSampleRate;
- framesInNeeded = ceil(framesOut * inOverOut) + 1;
+ // Do not precompute in/out because floating point is not associative
+ // e.g. a*b/c != a*(b/c).
+ const double in(mSampleRate);
+ const double out(activeTrack->mSampleRate);
+ framesInNeeded = ceil(framesOut * in / out) + 1;
ALOGV("need %u frames in to produce %u out given in/out ratio of %.4g",
- framesInNeeded, framesOut, inOverOut);
+ framesInNeeded, framesOut, in / out);
// Although we theoretically have framesIn in circular buffer, some of those are
// unreleased frames, and thus must be discounted for purpose of budgeting.
size_t unreleased = activeTrack->mRsmpInUnrel;
@@ -5309,24 +5311,24 @@
if (framesIn < framesInNeeded) {
ALOGV("not enough to resample: have %u frames in but need %u in to "
"produce %u out given in/out ratio of %.4g",
- framesIn, framesInNeeded, framesOut, inOverOut);
- size_t newFramesOut = framesIn > 0 ? floor((framesIn - 1) * outOverIn) : 0;
+ framesIn, framesInNeeded, framesOut, in / out);
+ size_t newFramesOut = framesIn > 0 ? floor((framesIn - 1) * out / in) : 0;
LOG_ALWAYS_FATAL_IF(newFramesOut >= framesOut);
if (newFramesOut == 0) {
break;
}
- framesInNeeded = ceil(newFramesOut * inOverOut) + 1;
+ framesInNeeded = ceil(newFramesOut * in / out) + 1;
ALOGV("now need %u frames in to produce %u out given out/in ratio of %.4g",
- framesInNeeded, newFramesOut, outOverIn);
+ framesInNeeded, newFramesOut, out / in);
LOG_ALWAYS_FATAL_IF(framesIn < framesInNeeded);
ALOGV("success 2: have %u frames in and need %u in to produce %u out "
"given in/out ratio of %.4g",
- framesIn, framesInNeeded, newFramesOut, inOverOut);
+ framesIn, framesInNeeded, newFramesOut, in / out);
framesOut = newFramesOut;
} else {
ALOGV("success 1: have %u in and need %u in to produce %u out "
"given in/out ratio of %.4g",
- framesIn, framesInNeeded, framesOut, inOverOut);
+ framesIn, framesInNeeded, framesOut, in / out);
}
// reallocate mRsmpOutBuffer as needed; we will grow but never shrink