Clamp AudioBuffer float to int{16,32} conversion

media/base/audio_bus.cc

Index: media/base/audio_bus.cc
diff --git a/media/base/audio_bus.cc b/media/base/audio_bus.cc
index 2b0379a7542bc4672abd51d256394b4700f7c94d..c808bcd81d92b9fc7509600013e98d35b057187a 100644
--- a/media/base/audio_bus.cc
+++ b/media/base/audio_bus.cc
@@ -12,13 +12,12 @@
 #include "base/logging.h"
 #include "base/numerics/safe_conversions.h"
 #include "media/audio/audio_parameters.h"
+#include "media/base/audio_sample_conversion.h"
 #include "media/base/limits.h"
 #include "media/base/vector_math.h"
 
 namespace media {
 
-static const uint8_t kUint8Bias = 128;
-
 static bool IsAligned(void* ptr) {
   return (reinterpret_cast<uintptr_t>(ptr) &
           (AudioBus::kChannelAlignment - 1)) == 0U;
@@ -40,51 +39,29 @@ static int CalculateMemorySizeInternal(int channels, int frames,
   return sizeof(float) * channels * aligned_frames;
 }
 
-// |Format| is the destination type.  If a bias is present, |Fixed| must be a
-// type larger than |Format| such that operations can be made without
-// overflowing.  Without a bias |Fixed| must be the same as |Format|.
-template<class Format, class Fixed, Format Bias>
-static void FromInterleavedInternal(const void* src, int start_frame,
-                                    int frames, AudioBus* dest,
-                                    float min, float max) {
-  static_assert((Bias == 0 && sizeof(Fixed) == sizeof(Format)) ||
-                sizeof(Fixed) > sizeof(Format), "invalid deinterleave types");
+template <class Format>
+static void FromInterleavedInternal(const void* src,
+                                    int start_frame,
+                                    int frames,
+                                    AudioBus* dest) {
   const Format* source = static_cast<const Format*>(src);
   const int channels = dest->channels();
   for (int ch = 0; ch < channels; ++ch) {
-    float* channel_data = dest->channel(ch);
-    for (int i = start_frame, offset = ch; i < start_frame + frames;
-         ++i, offset += channels) {
-      const Fixed v = static_cast<Fixed>(source[offset]) - Bias;
-      channel_data[i] = v * (v < 0 ? -min : max);
-    }
+    DeinterleaveOneChannel(source, start_frame, frames, dest->channel(ch),
+                           channels, ch);
   }
 }
 
-// |Format| is the destination type.  If a bias is present, |Fixed| must be a
-// type larger than |Format| such that operations can be made without
-// overflowing.  Without a bias |Fixed| must be the same as |Format|.
-template<class Format, class Fixed, Format Bias>
-static void ToInterleavedInternal(const AudioBus* source, int start_frame,
-                                  int frames, void* dst, Fixed min, Fixed max) {
-  static_assert((Bias == 0 && sizeof(Fixed) == sizeof(Format)) ||
-                sizeof(Fixed) > sizeof(Format), "invalid interleave types");
+template <class Format>
+static void ToInterleavedInternal(const AudioBus* source,
+                                  int start_frame,
+                                  int frames,
+                                  void* dst) {
   Format* dest = static_cast<Format*>(dst);
   const int channels = source->channels();
   for (int ch = 0; ch < channels; ++ch) {
-    const float* channel_data = source->channel(ch);
-    for (int i = start_frame, offset = ch; i < start_frame + frames;
-         ++i, offset += channels) {
-      const float v = channel_data[i];
-
-      Fixed sample;
-      if (v < 0)
-        sample = v <= -1 ? min : static_cast<Fixed>(-v * min);
-      else
-        sample = v >= 1 ? max : static_cast<Fixed>(v * max);
-
-      dest[offset] = static_cast<Format>(sample) + Bias;
-    }
+    InterleaveOneChannel(source->channel(ch), start_frame, frames, dest,
+                         channels, ch);
   }
 }
 
@@ -257,22 +234,13 @@ void AudioBus::FromInterleavedPartial(const void* source, int start_frame,
   CheckOverflow(start_frame, frames, frames_);
   switch (bytes_per_sample) {
     case 1:
-      FromInterleavedInternal<uint8_t, int16_t, kUint8Bias>(
-          source, start_frame, frames, this,
-          1.0f / std::numeric_limits<int8_t>::min(),
-          1.0f / std::numeric_limits<int8_t>::max());
+      FromInterleavedInternal<uint8_t>(source, start_frame, frames, this);
       break;
     case 2:
-      FromInterleavedInternal<int16_t, int16_t, 0>(
-          source, start_frame, frames, this,
-          1.0f / std::numeric_limits<int16_t>::min(),
-          1.0f / std::numeric_limits<int16_t>::max());
+      FromInterleavedInternal<int16_t>(source, start_frame, frames, this);
       break;
     case 4:
-      FromInterleavedInternal<int32_t, int32_t, 0>(
-          source, start_frame, frames, this,
-          1.0f / std::numeric_limits<int32_t>::min(),
-          1.0f / std::numeric_limits<int32_t>::max());
+      FromInterleavedInternal<int32_t>(source, start_frame, frames, this);
       break;
     default:
       NOTREACHED() << "Unsupported bytes per sample encountered.";
@@ -303,19 +271,13 @@ void AudioBus::ToInterleavedPartial(int start_frame, int frames,
   CheckOverflow(start_frame, frames, frames_);
   switch (bytes_per_sample) {
     case 1:
-      ToInterleavedInternal<uint8_t, int16_t, kUint8Bias>(
-          this, start_frame, frames, dest, std::numeric_limits<int8_t>::min(),
-          std::numeric_limits<int8_t>::max());
+      ToInterleavedInternal<uint8_t>(this, start_frame, frames, dest);
       break;
     case 2:
-      ToInterleavedInternal<int16_t, int16_t, 0>(
-          this, start_frame, frames, dest, std::numeric_limits<int16_t>::min(),
-          std::numeric_limits<int16_t>::max());
+      ToInterleavedInternal<int16_t>(this, start_frame, frames, dest);
       break;
     case 4:
-      ToInterleavedInternal<int32_t, int32_t, 0>(
-          this, start_frame, frames, dest, std::numeric_limits<int32_t>::min(),
-          std::numeric_limits<int32_t>::max());
+      ToInterleavedInternal<int32_t>(this, start_frame, frames, dest);
       break;
     default:
       NOTREACHED() << "Unsupported bytes per sample encountered.";