CODEWITHSUNDEEP
objective-ciphonexcodeaudiosqlite
Rahul Vyas
Rahul Vyas

Reputation: 28720

how do i store audio files in sqlite3 database and play them in iphone?

i want to store audio files(any of these formats mp3,wav,and iphone supported) in database and play them in iphone...any idea how to do this?

Upvotes: 3

Views: 7016

Answers (3)

Opptatt Jobber
Opptatt Jobber

Reputation: 319

It's not always best to store the file on disk. Have a look at this comparison:

http://www.sqlite.org/intern-v-extern-blob.html

Here is how I do it using ruby and the sequel gem:

Create a table using this schema. The file is a blob, the sha is the name of the file. In this case, all my files are variable bit rate mono mp3 files, 2K-3K in size. I have about 40 000 files in the db. I'm using a sha1 value as file name since I have a lot of entries that have the same sound so I'm saving some space.

CREATE TABLE `sound` (`id` integer PRIMARY KEY AUTOINCREMENT, `sha` text, `file` blob); CREATE INDEX `sound_sha_index` ON `sound` (`sha`);

Using ruby you can create the db like this:

db = Sequel.sqlite('./sound.db')     
db.create_table :sound do
  primary_key :id, :index => true   
  column :sha, :text, :index => true
  column :file, :blob 
end

Load the files into the database. Assuming you have the files in a directory called 'sound', here is how:

DB = Sequel.sqlite('./sound.db')
files = Dir['./sound/*.mp3']
files.each_with_index do |f, i|
  # progress
  print "\r #{((i.to_f / files.size)*100).round(2)}%"
  # get the file name without directory and extension
  f =~ /\/sound\/(.+)\.mp3/
  # insert into db
  DB[:sound].insert :sha => $1, :file => File.read("#{f}").to_sequel_blob
end

Play sound in the iPhone app. Copy the sound.db file to your iPhone project. This is the code I'm using. It's based on FMDB and AVAudioPlayer.

SoundPlayer.h

#import <Foundation/Foundation.h>
#import <AVFoundation/AVFoundation.h>
#import "FMDatabase.h"
#import "FMDatabaseQueue.h"

@interface SoundPlayer : NSObject
{
    FMDatabaseQueue *db;
}

@property (nonatomic, retain) AVAudioPlayer *audioPlayer;

- (void)play:(NSString *)sha;
- (void)free;
@end

SoundPlayer.m

#import "SoundPlayer.h"
#import "DictAppDelegate.h"

@implementation SoundPlayer

- (SoundPlayer*)init
{
    NSString *dbPath = [[[NSBundle mainBundle] resourcePath] stringByAppendingPathComponent:@"sound.db"];
    db = [FMDatabaseQueue databaseQueueWithPath: dbPath];

    return self;
}

- (void)play:(NSString *)sha
{
    [db inDatabase:^(FMDatabase *connection) {
        // Execute and fetch result
        NSString *query = [NSString stringWithFormat:@"select file from sound where sha = '%@' limit 1", sha];

        FMResultSet *rs = [connection executeQuery:query];

        while([rs next]) {

            NSData *file = [rs dataForColumn: @"file"];

            NSError *error;

            self.audioPlayer = [[AVAudioPlayer alloc] initWithData: file error:&error];
            self.audioPlayer.numberOfLoops = 0;
            self.audioPlayer.volume = 1.0f;
            [self.audioPlayer prepareToPlay];

            if (self.audioPlayer == nil) {
                NSLog(@"Error playing sound: %@", [error description]);
            } else {
                [self.audioPlayer play];
            }
        }
    }];
}

// Cleanup
- (void)free {
    [db close];
}

@end

Use the file from somewhere in your code like this:

self.soundPlayer = [[SoundPlayer alloc] init];
[self.soundPlayer play:[entry valueForKey:@"sha"]];

where [entry valueForKey:@"sha"]] returns a NSString which is the file name I have stored in my other table of entries.

Upvotes: 3

Lounges
Lounges

Reputation: 4664

In general it's best to not store binary files in any database. You are better off writing that file to the disk as a file and then storing the path in the database.

Upvotes: 2

hhafez
hhafez

Reputation: 39760

I don't know why you would want to store the audio files in a SQL database but sqlite3 supports BLOB. So store them as BLOB and retrieve them.

Alternatively why not store references to the files that you want to play?

Upvotes: 6

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