Adobe AIR Development

[SumiGhosh]

I want to save the image to application local folder, since my app get slowed while using database to save the images. Can anyone help me with the code.

[jtegen]

I believe you mean the app-storage folder. Just use the File class to manage the file, and FileStream to manage the i/o.

[SumiGhosh]

Im still stuck. I used FileRefernce class to save the image. But im not able to list it while using browse(). So anyone give me the right code for saving the image and retrieve it back..................

[pyth]

you shouldn't use filereference when you try something huge, use file and filestream as jtegen said. btw, using file also isn't very fast when you store a large amount of images

heree's a snippet that may be useful, storing bytearrays. you can convert images to bytearrays as well

//storing
						function writeFile(file:File, ba:ByteArray):void
						{
							
							if(file.exists == false) 
							{
								//create a default file
								var fs:FileStream = new FileStream(); 
								fs.open(file, FileMode.WRITE);
								fs.close();
							}
							
							var fileStream:FileStream = new FileStream();
							fileStream.open(file, FileMode.UPDATE); //tried using async, but that does not necessarily store the images (and also takes a lot time)
							fileStream.writeBytes(ba,0,ba.length);
							fileStream.close();
						}

//reading
var fs:FileStream;
						var ba:ByteArray;
						var file:File = //get your file
						if(file.exists) 
						{
							fs = new FileStream(); 
							ba = new ByteArray;
							fs.open(file, FileMode.READ);
							fs.readBytes(ba, 0, fs.bytesAvailable);
							fs.close();
							
							return ba;
						}

[SumiGhosh]

So how to convert it into image from bytearray. Im used bitmapData but that requires some additional parameter like width and height. 

[pyth]

a short google search returned this

//bitmapdata to bytearray

var ww:int = bitmapData.width;
                        var hh:int = bitmapData.height;
                        var ba:ByteArray = bitmapData.getPixels(new Rectangle(0,0,ww,hh));

//other way around

var bm:BitmapData = new BitmapData(ww, hh);
                        bm.setPixels(new Rectangle(0,0,ww,hh), ba);

                        var _img:Image = new Image();

                        _img.setImage(bm);

you need to store width and height though, and that's where you can use your database, because just storing numbers is faster than images

[SumiGhosh]

That code works fine for me. Is it possible to create a jpg image from the byte array. And bitmap is working fine for me...........

[SumiGhosh]

I checked the image size by putting it to document storage area. And i found the image sizes are larger comparitive to its original size.(eg. a 3.6kb image to 56kb and 20kb image around 500kb).

[pyth]

yes, that's because the bitmapdata of the image is bein read. so you can imagine that any compressed image like jpeg etc is being put pixel by pixel into a bitmap, making it uncompressed, which is why the image is significantly larger. :/

it also won't help if you tried to zip it, tried that already, didn't work

but maybe you could try to encode the bitmapData as JPEG or something, storing that as JPEGEncoded bytearray and decoding it when read again (google for AS3 jpeg encoder/decoder ?). would be awesome if you could share that

[SumiGhosh]

Yeah. I will try that and post here the  code.