How to use

determineScaleSize

method

in

com.atlassian.core.util.thumbnail.Thumber

private WidthHeightHelper determineScaleSize(int maxWidth, int maxHeight, Image image)
{
  return determineScaleSize(maxWidth, maxHeight, image.getWidth(null), image.getHeight(null));
}

private BufferedImage scaleImage(Image originalImage, int maxWidth, int maxHeight)
{
  return scaleImage(originalImage, determineScaleSize(maxWidth, maxHeight, originalImage));
}

  public UploadedAvatar scaleImageToTempFile(final Image sourceImage, final File targetFile, final int edgeSize)
      throws IOException
  {
    ThumbnailDimension targetDimension = thumber.determineScaleSize(edgeSize, edgeSize, sourceImage.getWidth(null), sourceImage.getHeight(null));
    BufferedImage scaledImage = thumber.scaleImage(sourceImage, targetDimension);

    ImageIO.write(scaledImage, AVATAR_IMAGE_FORMAT, targetFile);

    return new UploadedAvatar(targetFile, AVATAR_IMAGE_FORMAT_FULL.getContentType(), targetDimension.getWidth(), targetDimension.getHeight());
  }
}

private ResultAndContentTypeChanged cropImageToFile(final int edgeSize, final Image sourceImage)
{
  Result<File> prescaledFile = createTemporaryFile(TEMP_FILE_EXTENSION);
  if (!prescaledFile.isValid())
  {
    return new ResultAndContentTypeChanged(prescaledFile, false);
  }
  ThumbnailDimension dimensions = thumber.determineScaleSize(edgeSize, edgeSize, sourceImage.getWidth(null), sourceImage.getHeight(null));
  BufferedImage scaledImage = thumber.scaleImage(sourceImage, dimensions);
  try
  {
    ImageIO.write(scaledImage, AVATAR_IMAGE_FORMAT, prescaledFile.getResult());
    return new ResultAndContentTypeChanged(prescaledFile, true);
  }
  catch (IOException e)
  {
    return new ResultAndContentTypeChanged(new Result<File>().addError(getText("avatarpicker.upload.temp.io", e.getMessage()), ErrorCollection.Reason.SERVER_ERROR), false);
  }
}