Flash as3 online image processing before uploading

Flash Player 10 finally supports the image client processing and preview functions, greatly saving the bandwidth for uploading files/images to the website-happy, but only FP 10 supports pain, record important processes and hope to help you. currently, I only use the image upload function. The client re-encodes the image and changes the image size.

Prepare the flash cs4 environment, or flex builder. You need the FP 10 SDK. I like flex builder to create an as project. This small tool is the key. This release is only 20 K.

There are several open-source class libraries. The key is two, namely, javasencoder. As (note that this is not Adobe's jpgencoder. As, which can be done, but the efficiency is too low), uploadposthelper;

1. Use the built-in filereference, browse, and select of fp10 to open and load files;

2. Use javasencoder to compress and process images in JPG format;

3. You can use uploadposthelper. getpostdata to generate the post body. Because I want to upload both the file and form fields, it is critical to paste them.Code:

Key code

1 Public   Static Function compress (Source: ibitmapdrawable, W: uint =   1024 , H: uint =   1024 ): Bytearray {
2 VaR orgw: uint = Source. width;
3 VaR orgh: uint source. height;
4 VaR mat: Matrix =   New Matrix ();
5 If (Orgw > W | Orgh > H ){
6 VaR IP: Number = Orgw / Orgh;
7 If (IP >   1 ){
8 IP =   1024 / Orgw;
9 } Else {
10 IP =   1024 / Orgh;
11 }
12 W = IP * Orgw;
13 H = IP * Orgh;
14 Mat. Scale (IP, ip );
15 } Else {
16 W = Orgw;
17 H = Orgh;
18 }
19 VaR BPD: bitmapdata =   New Bitmapdata (W, H, True , 0x00ffffff );
20 BPD. Draw (source, mat ); // Zookeeper
21 VaR incluenc: incluencoder =   New Jpegencoder ( 80 );
22 Return Jpegenc. encode (BPD );
23 }
24
25 VaR DAT: bytearray = Picproccess. Compress (source, 800 , 600 );
26
27 ... ...
28
29 VaR postparams: Object =   New Object ();
30
31 Postparams. Username = "";
32
33 ... ... ...
34
35 VaR URLRequest: URLRequest =   New URLRequest (_ posturl );
36 URLRequest. Method = Urlrequestmethod. post;
37 URLRequest. Data = Uploadposthelper. getpostdata (_ file. Name, dat, ' Filename ' , Postparams );
38 URLRequest. requestheaders. Push ( New Urlrequestheader ( ' Cache-control ' , ' No-Cache ' ));
39 URLRequest. requestheaders. Push ( New Urlrequestheader ( ' Content-Type ' , ' Multipart/form-data; boundary = '   + Uploadposthelper. getboundary ()));
40 VaR urlloader: urlloader =   New Urlloader ();
41 Urlloader. dataformat = Urlloaderdataformat. Binary;
42 Urlloader. addeventlistener (ioerrorevent. io_error, uppicerror );
43 Urlloader. addeventlistener (securityerrorevent. security_error, uppicerror );
44 Urlloader. addeventlistener (httpstatusevent. http_status, uppicerror );
45 Urlloader. addeventlistener (event. Complete, uppiccompleted );
46 Urlloader. Load (URLRequest );
47

 

 

The server directly receives the same post form. there is basically no modification to the server code. When uploading images, I can process a maximum of 150 x pixels and kb. Otherwise, the current high-pixel camera is 10 MB, which makes it impossible for users to process images. or simply upload the data at 1 MB or 2 MB.