From 527006942268320a59ea4383ea1daffe19db8a9c Mon Sep 17 00:00:00 2001
From: Ahmet Inan <inan@aicodix.de>
Date: Wed, 12 Sep 2018 14:43:22 +0200
Subject: [PATCH] added rate() and channels() to pcm writer interface

---
 pcm.hh |  2 ++
 wav.hh | 26 ++++++++++++++++++--------
 2 files changed, 20 insertions(+), 8 deletions(-)

diff --git a/pcm.hh b/pcm.hh
index 5905a16..e015430 100644
--- a/pcm.hh
+++ b/pcm.hh
@@ -15,6 +15,8 @@ struct WritePCM
 	virtual void write(TYPE *, int, int = 1) = 0;
 	virtual bool good() = 0;
 	virtual void silence(int) = 0;
+	virtual int rate() = 0;
+	virtual int channels() = 0;
 };
 
 template <typename TYPE>
diff --git a/wav.hh b/wav.hh
index 3e432b1..39043c4 100644
--- a/wav.hh
+++ b/wav.hh
@@ -134,7 +134,7 @@ template <typename TYPE>
 class WriteWAV : public WritePCM<TYPE>
 {
 	std::ofstream os;
-	int bytes, channels;
+	int bytes, channels_, rate_;
 	int offset, factor, min, max;
 	void writeLE(int v, int b)
 	{
@@ -142,7 +142,9 @@ class WriteWAV : public WritePCM<TYPE>
 			os.put(255 & (v >> (8 * i)));
 	}
 public:
-	WriteWAV(const char *name, int rate, int bits, int channels) : os(name, std::ios::binary | std::ios::trunc), bytes(bits / 8), channels(channels)
+	WriteWAV(const char *name, int rate, int bits, int channels) :
+		os(name, std::ios::binary | std::ios::trunc),
+		bytes(bits / 8), channels_(channels), rate_(rate)
 	{
 		switch (bits) {
 			case 8:
@@ -183,10 +185,10 @@ public:
 		os.write("fmt ", 4); // Subchunk1ID
 		writeLE(16, 4); // Subchunk1Size
 		writeLE(1, 2); // AudioFormat
-		writeLE(channels, 2); // NumChannels
-		writeLE(rate, 4); // SampleRate
-		writeLE(rate * channels * bytes, 4); // ByteRate
-		writeLE(channels * bytes, 2); // BlockAlign
+		writeLE(channels_, 2); // NumChannels
+		writeLE(rate_, 4); // SampleRate
+		writeLE(rate_ * channels_ * bytes, 4); // ByteRate
+		writeLE(channels_ * bytes, 2); // BlockAlign
 		writeLE(8 * bytes, 2); // BitsPerSample
 		os.write("data", 4); // Subchunk2ID
 		writeLE(0, 4); // Subchunk2Size
@@ -202,7 +204,7 @@ public:
 	void write(TYPE *buf, int num, int stride = 1)
 	{
 		for (int n = 0; n < num; ++n) {
-			for (int c = 0; c < channels; ++c) {
+			for (int c = 0; c < channels_; ++c) {
 				TYPE v = TYPE(offset) + TYPE(factor) * buf[stride * n + c];
 				writeLE(std::nearbyint(std::clamp(v, TYPE(min), TYPE(max))), bytes);
 			}
@@ -214,9 +216,17 @@ public:
 	}
 	void silence(int num)
 	{
-		for (int i = 0; i < num * channels; ++i)
+		for (int i = 0; i < num * channels_; ++i)
 			writeLE(offset, bytes);
 	}
+	int channels()
+	{
+		return channels_;
+	}
+	int rate()
+	{
+		return rate_;
+	}
 };
 
 }