getting Image ThumbNail in Android

问题

I need Thumbnail of an image . I only know about the name of image which is stored in SD card . Can anyone help me.

回答1:

Try this.

final int THUMBSIZE = 64;

Bitmap ThumbImage = ThumbnailUtils.extractThumbnail(BitmapFactory.decodeFile(imagePath), 
                    THUMBSIZE, THUMBSIZE);

Refer this for more details.

回答2:

Using MediaStore.Images.Thumbnails you can query and get two kinds of thumbnails: MINI_KIND: 512 x 384 thumbnail MICRO_KIND: 96 x 96 thumbnail.

The advantage of using this call is that the thumbnails are cached by the MediaStore. So retrieval would be faster if the thumbnail was previously created.

回答3:

byte[] imageData = null;

try
{

final int THUMBNAIL_SIZE = 64;

FileInputStream fis = new FileInputStream(fileName);
Bitmap imageBitmap = BitmapFactory.decodeStream(fis);

Float width = new Float(imageBitmap.getWidth());
Float height = new Float(imageBitmap.getHeight());
Float ratio = width/height;
imageBitmap = Bitmap.createScaledBitmap(imageBitmap, (int)(THUMBNAIL_SIZE * ratio), THUMBNAIL_SIZE, false);

ByteArrayOutputStream baos = new ByteArrayOutputStream();
imageBitmap.compress(Bitmap.CompressFormat.JPEG, 100, baos);
imageData = baos.toByteArray();

}
catch(Exception ex) {

}

回答4:

If you like HQ thumbnails, so use [RapidDecoder][1] library. It is simple as follow:

import rapid.decoder.BitmapDecoder;
...
Bitmap bitmap = BitmapDecoder.from(getResources(), R.drawable.image)
                             .scale(width, height)
                             .useBuiltInDecoder(true)
                             .decode();

Don't forget to use builtin decoder if you want to scale down less than 50% and a HQ result.

来源：https://stackoverflow.com/questions/14110163/getting-image-thumbnail-in-android

标签

android

image

thumbnails