Android - 压缩位图,然后将其保存到SDCARD的活动结果中
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我一直在讨论这个问题,并不确定该怎么做。我要做的是:拍照,压缩到png(保持原始尺寸),然后将其保存到sdCard。我需要这样做的原因是因为我必须再次重新压缩它,然后Base64编码它,以便我可以将它发送到服务器。问题是1.文件太大2.我的内存不足3.不确定我是否正确执行此操作。
谢谢你的帮助
这是我的代码:
@Override
public void onClick(View button) {
switch (button.getId()) {
case R.id.cameraButton:
Intent cameraIntent = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);
cameraIntent.putExtra(android.provider.MediaStore.EXTRA_OUTPUT,
Uri.fromFile(new File("/sdcard/test.png")));
startActivityForResult(cameraIntent, CAMERA_PIC_REQUEST);
break;
case R.id.galleryButton:
sendToDatabase();
break;
}
}
// Camera on activity for result - save it as a bmp and place in imageview
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
if (requestCode == CAMERA_PIC_REQUEST) {
// do something
}
if (resultCode == Activity.RESULT_OK) {
Log.d(TAG, "result ok");
picture = BitmapFactory.decodeFile("/sdcard/test.png");
// Create string to place it in sd card
String extStorageDirectory = Environment
.getExternalStorageDirectory().toString();
//create output stream
OutputStream outputStream = null;
//create file
File file = new File(extStorageDirectory, "test.png");
try {
outputStream = new FileOutputStream(file);
picture.compress(Bitmap.CompressFormat.PNG, 80, outputStream);
//picture.recycle();
outputStream.flush();
outputStream.close();
} catch (IOException e){
Log.d(TAG, "ERROR");
}
imageView.setImageBitmap(picture);
}
}
public void sendToDatabase() {
InputStream inputStream = null;
//get the picture from location
picture = BitmapFactory.decodeFile("/sdcard/test.png");
// CONVERT:
ByteArrayOutputStream outStream = new ByteArrayOutputStream();
Boolean didItWork = picture.compress(Bitmap.CompressFormat.PNG, 50, outStream);
picture.recycle();
if (didItWork = true) {
Log.d(TAG, "compression worked");
}
Log.d(TAG, "AFTER. Height: " + picture.getHeight() + " Width: "
+ picture.getWidth());
final byte[] ba = outStream.toByteArray();
try {
outStream.close();
} catch (IOException e1) {
// TODO Auto-generated catch block
e1.printStackTrace();
}
}
答案
当你做picture.compress(Bitmap.CompressFormat.PNG,50,outStream);压缩不能作为无损的PNG工作,将忽略质量设置。因此参数50在这种情况下不起作用。所以我建议你将CompressFormat.PNG改为CompressFormat.JPEG。
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