Add a method for the input sample delay for the SampleConverter

2 files changed, 14 insertions, 1 deletions

diff --git a/core/converter.cpp b/core/converter.cpp
index 6a06b464..f4c36c87 100644
--- a/core/converter.cpp
+++ b/core/converter.cpp
@@ -167,8 +167,13 @@ SampleConverterPtr CreateSampleConverter(DevFmtType srcType, DevFmtType dstType,
     converter->mSrcTypeSize = BytesFromDevFmt(srcType);
     converter->mDstTypeSize = BytesFromDevFmt(dstType);
 
-    converter->mSrcPrepCount = 0;
+    converter->mSrcPrepCount = MaxResamplerEdge;
     converter->mFracOffset = 0;
+    for(auto &chan : converter->mChan)
+    {
+        const al::span<float> buffer{chan.PrevSamples};
+        std::fill(buffer.begin(), buffer.end(), 0.0f);
+    }
 
     /* Have to set the mixer FPU mode since that's what the resampler code expects. */
     FPUCtl mixer_mode{};
diff --git a/core/converter.h b/core/converter.h
index 2d22ae38..46d9b83e 100644
--- a/core/converter.h
+++ b/core/converter.h
@@ -1,6 +1,7 @@
 #ifndef CORE_CONVERTER_H
 #define CORE_CONVERTER_H
 
+#include <chrono>
 #include <cstddef>
 #include <memory>
 
@@ -37,6 +38,13 @@ struct SampleConverter {
     uint convert(const void **src, uint *srcframes, void *dst, uint dstframes);
     uint availableOut(uint srcframes) const;
 
+    using SampleOffset = std::chrono::duration<int64_t, std::ratio<1,MixerFracOne>>;
+    SampleOffset currentInputDelay() const noexcept
+    {
+        const int64_t prep{mSrcPrepCount - MaxResamplerEdge};
+        return SampleOffset{(prep<<MixerFracBits) + mFracOffset};
+    }
+
     DEF_FAM_NEWDEL(SampleConverter, mChan)
 };
 using SampleConverterPtr = std::unique_ptr<SampleConverter>;