AudioFormat: add TimeToSize(), SizeToTime()

src/AudioFormat.hxx

@@ -23,6 +23,8 @@
 #include "pcm/SampleFormat.hxx"
 #include "util/Compiler.h"
 
+#include <chrono>
+
 #include <stdint.h>
 #include <stddef.h>
 
@@ -152,6 +154,28 @@ struct AudioFormat {
 	 * span to a storage size in bytes.
 	 */
 	double GetTimeToSize() const;
+
+	template<typename D>
+	constexpr auto TimeToFrames(D t) const noexcept {
+		using Period = typename D::period;
+		return ((t.count() * sample_rate) / Period::den) * Period::num;
+	}
+
+	template<typename D>
+	constexpr size_t TimeToSize(D t) const noexcept {
+		return size_t(size_t(TimeToFrames(t)) * GetFrameSize());
+	}
+
+	template<typename D>
+	constexpr D FramesToTime(std::uintmax_t size) const noexcept {
+		using Period = typename D::period;
+		return D(((size / Period::num) * Period::den) / sample_rate);
+	}
+
+	template<typename D>
+	constexpr D SizeToTime(std::uintmax_t size) const noexcept {
+		return FramesToTime<D>(size / GetFrameSize());
+	}
 };
 
 /**

src/decoder/Bridge.cxx

@@ -532,8 +532,7 @@ DecoderBridge::SubmitData(InputStream *is,
 		data = (const uint8_t *)data + nbytes;
 		length -= nbytes;
 
-		timestamp += FloatDuration((double)nbytes /
-					   dc.out_audio_format.GetTimeToSize());
+		timestamp += dc.out_audio_format.SizeToTime<FloatDuration>(nbytes);
 	}
 
 	absolute_frame += data_frames;

src/decoder/plugins/HybridDsdDecoderPlugin.cxx

@@ -183,7 +183,7 @@ HybridDsdDecode(DecoderClient &client, InputStream &input)
 
 	try {
 		auto result = FindHybridDsdData(client, input);
-		auto duration = SignedSongTime::FromS(result.second / result.first.GetTimeToSize());
+		auto duration = result.first.SizeToTime<SignedSongTime>(result.second);
 		client.Ready(result.first, true, duration);
 		frame_size = result.first.GetFrameSize();
 		kbit_rate = frame_size * result.first.sample_rate /

src/decoder/plugins/Mpg123DecoderPlugin.cxx

@@ -264,8 +264,7 @@ mpd_mpg123_file_decode(DecoderClient &client, Path path_fs)
 				client.SeekError();
 			else {
 				client.CommandFinished();
-				client.SubmitTimestamp(FloatDuration(c)
-						       / audio_format.sample_rate);
+				client.SubmitTimestamp(audio_format.FramesToTime<FloatDuration>(c));
 			}
 
 			cmd = DecoderCommand::NONE;

src/player/Thread.cxx

@@ -766,7 +766,7 @@ PlayerControl::PlayChunk(DetachedSong &song, MusicChunkPtr chunk,
 	const double chunk_length(chunk->length);
 
 	outputs.Play(std::move(chunk));
-	total_play_time += FloatDuration(chunk_length / format.GetTimeToSize());
+	total_play_time += format.SizeToTime<decltype(total_play_time)>(chunk_length);
 }
 
 inline bool