experimental TimeInfoStream

Author: pschatzmann

README.md

@@ -95,7 +95,7 @@ void loop(){
 
 ```
 Each stream has it's own [configuration object](https://pschatzmann.github.io/arduino-audio-tools/html/structaudio__tools_1_1_audio_base_info.html) that should be passed to the begin method. The defaultConfig() method is providing a default proposal which will usually "just work". Please consult 
-the class documentation for the available configuration parameters. You can also easily adapt any provided examples: If you e.g. replace the I2SStream with the AnalogAudioStream class, you will get analog instead of digital output.
+the class documentation for the available configuration parameters. You can also __easily adapt__ any provided examples: If you e.g. replace the I2SStream with the AnalogAudioStream class, you will get analog instead of digital output.
 
 Further examples can be found in the [Wiki](https://github.com/pschatzmann/arduino-audio-tools/wiki/Examples). 
 

src/AudioTools/AudioOutput.h

@@ -56,7 +56,7 @@ class AudioPrint : public Print, public AudioBaseInfoDependent, public AudioBase
             return false;
         }
 
-        virtual AudioBaseInfo audioInfo() {
+        virtual AudioBaseInfo audioInfo() override {
             return cfg;
         }
 

src/AudioTools/AudioStreams.h

@@ -62,7 +62,7 @@ class AudioStream : public Stream, public AudioBaseInfoDependent, public AudioBa
 
   operator bool() { return available() > 0; }
 
-  virtual AudioBaseInfo audioInfo() {
+  virtual AudioBaseInfo audioInfo() override {
     return info;
   }
 

src/AudioTools/AudioTypes.h

@@ -63,6 +63,7 @@ class AudioBaseInfoDependent {
     public:
       virtual ~AudioBaseInfoDependent(){}
       virtual void setAudioInfo(AudioBaseInfo info)=0;
+      virtual AudioBaseInfo audioInfo() = 0;
       virtual bool validate(AudioBaseInfo &info){
         return true;
       }

src/Experiments/TimeInfoStream.h

@@ -0,0 +1,101 @@
+#pragma once
+
+#include "AudioTools/AudioStreams.h"
+
+namespace audio_tools {
+
+/**
+ * @brief Wrapper class that can define a start and (an optional) stop time
+ * Only wrap classes which represent PCM data!
+ * @author Phil Schatzmann
+ * @copyright GPLv3
+ */
+class TimeInfoStream : public AudioStreamX {
+    public:
+        TimeInfoStream(AudioStream &io, long startSeconds=0, long endSeconds=-1){
+            p_stream = &io;
+            p_print = &io;
+            p_info = &io;
+            start_time = startSeconds;
+            end_time = endSeconds;
+        }
+
+        TimeInfoStream(AudioPrint &o,long startSeconds=0, long endSeconds=-1){
+            p_print = &o;
+            p_info = &o;
+            start_time = startSeconds;
+            end_time = endSeconds;
+        }
+
+        void setStartTime(long startSeconds){
+            start_time = startSeconds;
+        }
+
+        void setEndTime(long endSeconds){
+            end_time = endSeconds;
+        }
+
+        /// Resets the current time 
+        void setCurrentTime(double timeScalculateTimeeStartSeconds=0) {
+            current_time = timeScalculateTimeeStartSeconds;
+            bytes_per_second = -1.0; // trigger new calculation
+        }
+
+        /// Provides the current time in seconds from the start
+        double currentTime() {
+            return current_time;
+        }
+
+        /// Returns true if we are in a valid time range and are still playing sound 
+        bool isPlaying() {
+            if (current_time<start_time) return false;
+            if (end_time>0 && current_time>end_time) return false;
+            return true;
+        }
+
+        /// Returns true if we are not past the end time; 
+        bool isActive() {
+            if (end_time>0 && current_time>end_time) return false;
+            return true;
+        }
+
+        operator bool() {
+            return isActive();
+        }
+
+        size_t readBytes(uint8_t *buffer, size_t length) override { 
+            if (p_stream==nullptr) return 0;
+            calculateTime(length); 
+            return isPlaying()?p_stream->readBytes(buffer, length):length; 
+        }
+
+        size_t write(const uint8_t *buffer, size_t length) override{ 
+            calculateTime(length); 
+            return isPlaying()?p_print->write(buffer, length):length;  
+        }
+
+        int available() override { return p_stream!=nullptr ? p_stream->available():0; };
+        int availableForWrite() override { return p_print->availableForWrite(); }
+
+    protected:    
+        Stream *p_stream=nullptr;
+        Print *p_print=nullptr;
+        AudioBaseInfoDependent *p_info=nullptr;
+        long start_time = 0;
+        long end_time = -1;
+        double current_time = 0; 
+        double bytes_per_second = -1.0;
+
+        void calculateTime(int bytes){
+            if (bytes_per_second<0.0){
+                int channels = p_info->audioInfo().channels;
+                int sample_rate = p_info->audioInfo().sample_rate; // frames per second
+                int bytes_per_sample = p_info->audioInfo().bits_per_sample / 8;
+                bytes_per_second =  sample_rate * channels * bytes_per_sample;
+            }
+            current_time = static_cast<double>(bytes) / bytes_per_second;
+        }
+
+};
+
+}