图像重新缩放并在黑莓中写入重新缩放的图像文件

时间:2010-05-19 06:16:03

标签: blackberry jde

我使用以下代码调整大小并将文件保存到blackberry设备中。在图像缩放后,我尝试将图像文件写入设备。但它提供了相同的数据。 (图像的高度和宽度相同)。我必须重新缩放图像文件。任何人都可以帮我???

类ResizeImage扩展MainScreen实现了FieldChangeListener {     private String path =“file:///SDCard/BlackBerry/pictures/test.jpg”;     私人ButtonField btn;     ResizeImage()     {         btn = new ButtonField(“Write File”);         btn.setChangeListener(本);         添加(BTN);       }       public void fieldChanged(Field field,int context)       {             if(field == btn)             {                 尝试                 {
                    InputStream inputStream = null;                     //获取文件连接                     FileConnection fileConnection =(FileConnection)Connector.open(path);                     if(fileConnection.exists())                     {                         inputStream = fileConnection.openInputStream();                         // byte data [] = inputStream.toString()。getBytes();

                    ByteArrayOutputStream baos = new ByteArrayOutputStream();
                    int j = 0;
                    while((j=inputStream.read()) != -1) {
                    baos.write(j);
                    }
                    byte data[] = baos.toByteArray();                
                    inputStream.close();
                    fileConnection.close();  

                    WriteFile("file:///SDCard/BlackBerry/pictures/org_Image.jpg",data);           


                    EncodedImage  eImage = EncodedImage.createEncodedImage(data,0,data.length);                               
                    int scaleFactorX = Fixed32.div(Fixed32.toFP(eImage.getWidth()), Fixed32.toFP(80));
                    int scaleFactorY = Fixed32.div(Fixed32.toFP(eImage.getHeight()), Fixed32.toFP(80));
                    eImage=eImage.scaleImage32(scaleFactorX, scaleFactorY);   

                    WriteFile("file:///SDCard/BlackBerry/pictures/resize.jpg",eImage.getData());

                    BitmapField bit=new BitmapField(eImage.getBitmap());                       
                    add(bit);

                }       
            }
            catch(Exception e)
            {
                System.out.println("Exception is ==> "+e.getMessage());
            }

        }
   }


   void WriteFile(String fileName,byte[] data)
   {
       FileConnection fconn = null;
        try
        {
            fconn = (FileConnection) Connector.open(fileName,Connector.READ_WRITE);
        } 
        catch (IOException e) 
        {
            System.out.print("Error opening file");
        }

        if (fconn.exists())
        try 
        {
            fconn.delete();
        }
        catch (IOException e)
        {
            System.out.print("Error deleting file");
        }
        try 
        {
            fconn.create();
        }
        catch (IOException e) 
        {
            System.out.print("Error creating file");
        }
        OutputStream out = null;
        try
        {
            out = fconn.openOutputStream();
        } 
        catch (IOException e) {
            System.out.print("Error opening output stream");
        }

        try 
        {
            out.write(data);
        }
        catch (IOException e) {
            System.out.print("Error writing to output stream");
        }

        try
        {
            fconn.close();
        } 
        catch (IOException e) {
            System.out.print("Error closing file");
        }
    }

}

1 个答案:

答案 0 :(得分:0)

在EncodedImage中查看getScaledHeight()和getScaledWidth()。

这是一个肮脏的RIM技巧。

如果使用具有有效getHeight()和getWidth()的getBitmap()剥离位图。

然后,如果您想将该缩放图像保存为jpeg,则需要重新编码。

e.g。

Bitmap scaledBMP = scaledEI.getBitmap();
JPEGEncodedImage finalJPEG = JPEGEncodedImage.encode(scaledBMP, 80); // int arg is quality
raw_media_bytes = finalJPEG.getData();
raw_length = finalJPEG.getLength();
raw_offset = finalJPEG.getOffset();

// don't forget to use the length and offset info, because getData() is
// not guaranteed to work by itself.

AFAIK,预售5.0,至少没有原生的in-jpeg缩放,无需转换为位图。