Make background transparent in image.(Example image attached)

Question

How can I remove white background color(white in this) from image?. Or Want to make image background transparent.

These are two images.
Image 1 is: Text with white background
Image 2 is: Green(or close to green color) image

I need to make white remove background transparent of image 1

Answer 1

Here is an example to make BLUE color transparent in this image.

Here we have an Image with a blue background like and we want to display it in an Applet with a white background. All we have to do is to look for the blue color with the "Alpha bits" set to opaque and make them transparent.

You can adapt it and make WHITE color transparent.

Also you can check this answer.

Answer 2

The question is that, you want to make background transparent at runtime or just this image? if just this one then you should edit the image with any tool like irfanView to remove background color. just open this image in this tool and then save it as PNG and tick save transparent color and untick use window background color and then press enter. After that select white color.

Answer 3

You can do it easily with photoshop.

Using the magic wand or lasso tool, select the area of the image you want to be transparent.

and then just hit DELETE button.

for additional information check this link

you can also check this tutorial

here is useful video

Answer 4

when i had to solve that problem i used a buffer...

private IntBuffer buffer;
public void toBuffer(File tempFile){
    final Bitmap temp = BitmapFactory.decodeFile(imgSource
            .getAbsolutePath());
    buffer.rewind(); //setting the buffers index to '0'
    temp.copyPixelsToBuffer(buffer);
}

then you can simply edit all pixels (int-values) on your buffer (as mentioned from https://stackoverflow.com/users/3850595/jordi-castilla) ... ...setting ARGB for 0xFFFFFFFF (white&transparent) to 0x00?????? (any color would suit, it's transparent anyway)

so here's your code to edit transparenty on a buffer:

public void convert(){
    for (int dy = 0; dy < imgHeight; dy ++){            
        for (int dx = 0; dx < imgWidth; dx ++ ){

            int px = buffer.get();
            int a = (0xFF000000 & px) >> 24;
            int r = (0x00FF0000 & px) >> 16;
            int g = (0x0000FF00 & px) >> 8;
            int b = (0x000000FF & px);

            int result = px;    

            if (px == 0xFFFFFFFF){ //only adjust alpha when the color is 'white'
               a = 0xFF000000; //transparent? 
               int result = a | r | g | b;
            }

            int pos = buffer.position();
            buffer.put(pos-1, result);
        }       
    }

later you want to write back your image into an converted file:

public void copyBufferIntoImage(File tempFile) throws IOException {
    buffer.rewind();
    Bitmap temp = Bitmap.createBitmap(imgWidth, imgHeight,
            Config.ARGB_8888);
    temp.copyPixelsFromBuffer(buffer);

    FileOutputStream out = new FileOutputStream(tempFile);
    temp.compress(Bitmap.CompressFormat.PNG, 90, out);
    out.flush();
    out.close();
}

maybe you still want to know how to map a buffer?

    public void mapBuffer(final File tempFile, long size) throws IOException {

    RandomAccessFile aFile = new RandomAccessFile(tempFile, "rw");
    aFile.setLength(4 * size); // 4 byte pro int
    FileChannel fc = aFile.getChannel();
    buffer = fc.map(FileChannel.MapMode.READ_WRITE, 0, fc.size())
            .asIntBuffer();

}