Soundtouch for iPhone - iphone

Question

Has someone been able to make
http://www.surina.net/soundtouch/
work for iPhone?
Simple Xcode Demo would be helpful.
I'd just like to play a soundeffect with some pitch manipulation.
thx
chris

Answer 1

The best way to implement audio effects using SoundTouch is using also SoundStretch.
You can download the source code of both from here http://www.surina.net/soundtouch/sourcecode.html
SoundStretch is a command-line program that performs SoundTouch
library effects on WAV audio files. The program is a source code
example how SoundTouch library routines can be used to process sound
in other programs, but it can be used as a stand-alone audio
processing tool as well.
SoundStretch features:
Reads & writes .wav audio files
Allows very broad parameter adjustment ranges:
Tempo & Playback Rate adjustable in range -95% .. +5000%
The sound Pitch (key) adjustable in range -60 .. +60 semitones (+- 5 octaves).
Beats-Per-Second (BPM) detection that can adjust tempo to match with the desired BPM rate.
Full source codes available
Command-line interface allows using the SoundStretch utility for processing .wav audio files in batch mode
Supports processing .wav audio streams through standard input/output pipes
SoundStretch uses the SoundTouch library routines for the audio procesing.
Example of use:
NSArray *effects = [NSArray arrayWithObjects:#"-rate=-22", nil];
NSURL *audio = [self base:input output:output effects:effects];
Where base:output:effects is defined as:
- (NSURL *)base:(NSURL *)input output:(NSURL *)output effects:(NSArray *)effects{
int _argc = 3 + (int)[effects count];
const char *_argv[]={"createWavWithEffect",[[input path] UTF8String], [[output path] UTF8String],[#"" UTF8String],[#"" UTF8String],[#"" UTF8String],[#"" UTF8String],[#"" UTF8String],[#"" UTF8String],[#"" UTF8String],[#"" UTF8String],[#"" UTF8String]};
for (int i=0; i<[effects count]; i++) {
_argv[i+3] = [effects[i] UTF8String];
}
createWavWithEffect(_argc, _argv);
// IMPORTANT! Check the file size, maybe you will need to set by yourself
return output;
}
If you don't want to compile by yourself SoundTouch, I have shared a GitHub repository with that libraries compiled for armv7, armv7s, arm64, i386 and x86_64
https://github.com/enrimr/soundtouch-ios-library
And if you want to use SoundTouch by yourself without using SoundStretch, you have to add SoundTouch directory (which includes libSoundTouch.a and the directory with headers) in your Xcode project.
For SWIFT projects:
Programming with SWIFT you can't import a .h so you will need to create a .h file named <Your-Project-Name>-Bridging-Header-File.h
Then reference it in your projects build settings (under "Swift Compiler" look for "Objective C Bridging Header") with:
$(SRCROOT)/<Your-Project-Name>-Bridging-Header.h
And now you must be able to use SoundTouch class.
For Objective-C projects:
Include the following line
#include "SoundTouch.h"
in your controller file.
Implementation of createWavWithEffect:
int createWavWithEffect(const int nParams, const char * const paramStr[])
{
WavInFile *inFile;
WavOutFile *outFile;
RunParameters *params;
SoundTouch soundTouch;
fprintf(stderr, _helloText, SoundTouch::getVersionString());
try
{
// Parse command line parameters
params = new RunParameters(nParams, paramStr);
// Open input & output files
openFiles(&inFile, &outFile, params);
if (params->detectBPM == TRUE)
{
// detect sound BPM (and adjust processing parameters
// accordingly if necessary)
detectBPM(inFile, params);
}
// Setup the 'SoundTouch' object for processing the sound
setup(&soundTouch, inFile, params);
// clock_t cs = clock(); // for benchmarking processing duration
// Process the sound
process(&soundTouch, inFile, outFile);
// clock_t ce = clock(); // for benchmarking processing duration
// printf("duration: %lf\n", (double)(ce-cs)/CLOCKS_PER_SEC);
// Close WAV file handles & dispose of the objects
delete inFile;
delete outFile;
delete params;
fprintf(stderr, "Done!\n");
}
catch (const runtime_error &e)
{
// An exception occurred during processing, display an error message
fprintf(stderr, "%s\n", e.what());
return -1;
}
return 0;
}