is it Possible to Resize a Picture in MIDP1 ?

[mehiii2]

i know how can i Resize a picture with MIDP2 ,
is it Possible to do this with MIDP1 ?


thanks..

[shmoove]

It's possible but not easy. The problem is that MIDP 1.0 doesn't give you any methods to get the pixel data of the picture. So in order to use the method I gave you in the other thread you would have to write your own png decoding/encoding method.

You can find some code to get you started on that here.

shmoove

[mehiii2]

I can get the Hexa Nr of a Picture by some Editor and put it in a byte Array
and


static byte dukeData[] = {

(byte)0x89,(byte)0x50,(byte)0x4E,(byte)0x47,(byte)0x0D
,...........}

img = Image.createImage(dukeData, 0, dukeData.length);




if i have the byteArray, can i use the Hexa Nr for Resizing with MIDP2 code ,which you gave me ?

[shmoove]

No because that data is not raw pixel data (which is what you need for the resizing algorithm), it's encoded (usually PNG encoded) data.

That's why I said you have to write methods to decode (to get the raw pixel data from the encoded data) and encode (so you can convert the resized pixel data into a byte array that you can use with createImage) images.

You can get the specification for PNG and other formats from Wotsit.

shmoove

[Cheiz]

It's not necessary to write your own decoding algorythm. You can let the JVM + Nokia UI do it for you by drawing the PNG on an off-screen graphics context and the use GetPixels to get the pixeldata. Here's the code I use in my program(designed for MIDP1.0 12bit color):

Image temp = Image.createImage("/crosshair.gif");
Image workSpaceImg = Image.createImage(16,16);
DirectGraphics workSpace = DirectUtils.getDirectGraphics(workSpaceImg.getGraphics());
workSpace.drawImage(temp, 0, 0, Graphics.LEFT | Graphics.TOP, 0);
workSpace.getPixels(image, 0, 16, 0, 0, 16, 16, DirectGraphics.TYPE_USHORT_4444_ARGB);

What it does: it creates a blank 16x16 image plus an image from the GIF file, gets the graphics context of the blank image, draws the GIF image on that context, and gets the pixels(image is a short[] array)

Encoding is not possible this way i guess, so for that you have to write some code.

[The.French.DJ]

Probably a bit too late..

But an obvious solution is to scale a source image vertically first by blitting only the required lines to a temporary image. Then doing the same horizontally.

I use this approach to have a generic MIDP1 scaling method in a small slideshow engine.

cheers,

tfdj

[Rafoso]

Creating a Thumbnail Image
source: http://developers.sun.com/techtopics...icles/picture/

One seemingly simple thing I wanted to do in this article was talk about how to create a thumbnail image, a smaller version of the image captured from the camera. MIDP 2.0 includes methods for obtaining the raw pixel values of an Image, which would make a true scaling transformation possible. Unfortunately MIDP 1.0 does not provide access to the pixel data.

The solution I implemented is neither elegant nor strictly correct (in an image-processing sense), but it approximates the behavior I wanted and doesn't involve parsing the PNG format. I create a new (blank) image for the thumbnail. For each pixel of that image, I set the clipping region to encompass that single pixel, and draw the source image at an appropriately scaled location.

private Image createThumbnail(Image image) {
int sourceWidth = image.getWidth();
int sourceHeight = image.getHeight();

int thumbWidth = 64;
int thumbHeight = -1;

if (thumbHeight == -1)
thumbHeight = thumbWidth * sourceHeight / sourceWidth;

Image thumb = Image.createImage(thumbWidth, thumbHeight);
Graphics g = thumb.getGraphics();

for (int y = 0; y < thumbHeight; y++) {
for (int x = 0; x < thumbWidth; x++) {
g.setClip(x, y, 1, 1);
int dx = x * sourceWidth / thumbWidth;
int dy = y * sourceHeight / thumbHeight;
g.drawImage(image, x - dx, y - dy,
Graphics.LEFT | Graphics.TOP);
}
}

Image immutableThumb = Image.createImage(thumb);

return immutableThumb;
}