From 5c5e42a26df6bd5afa05750967352ffa15a67e29 Mon Sep 17 00:00:00 2001
From: Tim Redfern <tim@herge.(none)>
Date: Wed, 27 Mar 2013 17:16:25 +0000
Subject: nearly reading samples

---
 rotord/rotor.cpp | 66 ++++++++++++++++++++++++++++++++++++++++++++++++++++++--
 1 file changed, 64 insertions(+), 2 deletions(-)

(limited to 'rotord/rotor.cpp')

diff --git a/rotord/rotor.cpp b/rotord/rotor.cpp
index 85382ea..36cc6f3 100644
--- a/rotord/rotor.cpp
+++ b/rotord/rotor.cpp
@@ -119,7 +119,7 @@ Command_response Render_context::session_command(const std::vector<std::string>&
 				response.description="<status context='"+command[1]+"'>Rotor: audio ready</status>\n";
 				response.description+="<audio>\n";
 				response.description+=audio_thumb->print();
-				response.description+="\n</audio>";
+				response.description+="</audio>";
 				state=IDLE;
 			}
 	     }
@@ -536,7 +536,7 @@ bool Render_context::load_audio(const string &filename,vector<base_audio_process
 				// documentation on an FFmpeg structure or function, I just type "<name> doxygen" into google (like
 				// "AVFrame doxygen" for AVFrame's docs)
 
-				//std::cout << "Got a frame: bytes " << bytes << std::endl;
+				//std::cout << "Got a frame: bytes " << bytes << ", "<<frame->nb_samples<<" samples"<<std::endl;
 				//now we can pass the data to the processor(s)
 				for (auto p: processors) {
 					sample_processed=p->process_frame(frame->data[0],frame->nb_samples);
@@ -633,3 +633,65 @@ Node_factory::Node_factory(){
 	add_type("==",new Is_new_integer());
 	add_type("signal_output",new Signal_output());
 }
+void audio_thumbnailer::init(int _channels,int _bits,int _samples) {
+	//base_audio_processor::init(_channels,_bits,_samples);
+	channels=_channels;
+	bits=_bits;
+	samples=_samples;
+
+
+	samples_per_column=samples/width;
+	column=0; //point thumbnail bitmap
+	out_sample=0; //sample in whole track
+	offset=(int)(pow(2.0,bits)/2.0);
+	scale=1.0/offset;
+}
+int audio_thumbnailer::process_frame(uint8_t *_data,int samples_in_frame){
+	//begin by processing remaining samplesthread 4
+    //samples per column could be larger than a frame! (probably is)
+	//but all we are doing is averaging
+  int bytes=(bits>>3);
+	int stride=channels*bytes;
+	int in_sample=0;
+	while (in_sample<samples_in_frame&&column<width) {
+		int sample=0;
+		int samples=0;
+		double accum=0;
+		while (sample<samples_per_column&&in_sample<samples_in_frame) {
+			//accumulate squares for this column
+			for (int i=0;i<channels;i++) {
+				int this_val=0;
+				for (int j=0;j<bytes;j++) {
+					this_val+=_data[(sample*stride)+(i*bytes)+j]<<(j*8);
+				}
+				//convert from integer data format - i.e s16p - to audio signal in -1..1 range
+				//don't know how many bytes we are dealing with necessarily?
+				double val=((double)(this_val-offset))*scale;
+				accum+=(val*val);
+				samples++;
+			}
+			in_sample++;
+			sample++;
+			out_sample++;
+		}
+		//get root-mean
+		double mean=pow(accum/samples,0.5);
+		int colheight=height*mean*0.5;
+		int hh=height>>1;
+		for (int i=0;i<height;i++) {
+			data[i*width+column]=abs(i-hh)<colheight?0xff:0x00;
+		}
+		column++;
+	}
+	return out_sample;
+}
+string audio_thumbnailer::print(){
+	string output;
+	for (int j=0;j<height;j++) {
+		for (int i=0;i<width;i++) {
+			output+=data[j*width+i]<0x7f?"0":"1";
+		}
+		output +="\n";
+	}
+	return output;
+}
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