我正在使用以下代码在Android中向图像添加文本:
public Bitmap drawTextToBitmap(Context gContext, Bitmap image, String gText) {
Resources resources = gContext.getResources();
float scale = resources.getDisplayMetrics().density;
android.graphics.Bitmap.Config bitmapConfig =
image.getConfig();
// set default bitmap config if none
if(bitmapConfig == null) {
bitmapConfig = android.graphics.Bitmap.Config.ARGB_8888;
}
// resource bitmaps are imutable,
// so we need to convert it to mutable one
Bitmap bitmap = null;
try{
bitmap = image.copy(bitmapConfig, true);
image.recycle();
Canvas canvas = new Canvas(bitmap);
// new antialised Paint
Paint paint = new Paint(Paint.ANTI_ALIAS_FLAG);
// text color - #3D3D3D
paint.setColor(Color.WHITE);
// text size in pixels
paint.setTextSize((int) (50 * scale));
// text shadow
paint.setShadowLayer(1f, 0f, 1f, Color.BLACK);
// draw text to the Canvas center
Rect bounds = new Rect();
paint.getTextBounds(gText, 0, gText.length(), bounds);
int padding = bounds.height()/2;
int x = bitmap.getWidth() - (bounds.width()+padding);
int y = (bitmap.getHeight() - (bounds.height()+padding));
canvas.drawText(gText, x, y, paint);
}catch (Throwable e){
AppLog.e("DrawingBitmap","error while adding timestamp",e);
}
return bitmap;
}
然后我用转换后的位图创建了一个新文件。storeImage(newBitmap, newFileName);
private File storeImage(Bitmap image, String nameFile) {
File pictureFile = new File(getExternalCacheDir(), nameFile);
try {
FileOutputStream fos = new FileOutputStream(pictureFile);
image.compress(Bitmap.CompressFormat.JPEG, 100, fos);
fos.close();
} catch (FileNotFoundException e) {
AppLog.e("error creating bitmap", "File not found: " + e.getMessage());
} catch (IOException e) {
AppLog.e("error creating bitmap", "Error accessing file: " + e.getMessage());
}
return pictureFile;
}
我将文件发送到服务器,接收输入流,创建一个文件,按比例缩放它,并创建一个带有缩放图像的新文件:
ImageWriter.write(metadata, new IIOImage(image, null, metadata), param);
我收到了一个IIOException错误:
javax.imageio.IIOException: Missing Huffman code table entry
at com.sun.imageio.plugins.jpeg.JPEGImageWriter.writeImage(Native Method)
at com.sun.imageio.plugins.jpeg.JPEGImageWriter.writeOnThread(JPEGImageWriter.java:1067)
at com.sun.imageio.plugins.jpeg.JPEGImageWriter.write(JPEGImageWriter.java:363)
at com.twelvemonkeys.imageio.plugins.jpeg.JPEGImageWriter.write(JPEGImageWriter.java:162)
如果我不从安卓中调用drawTextToBitmap(),就不会出现那个错误。
如果有人能帮忙...谢谢
编辑:这是我用来获取文件元数据的方式。
private static IIOMetadata readMetaData(File source) {
try {
ImageInputStream stream = ImageIO.createImageInputStream(source);
Iterator<ImageReader> readers = ImageIO.getImageReaders(stream);
IIOMetadata metadata = null;
if (readers.hasNext()) {
ImageReader reader = readers.next();
reader.setInput(stream);
metadata = reader.getImageMetadata(0);
}
return metadata;
}catch (Exception e){
_logger.error(e);
e.printStackTrace();
}
return null;
}
编辑2:
使用jpegParams.setOptimizeHuffmanTables(true);可以解决问题,但会重置所有元数据,我想保留它们,例如GPS位置...
ImageWriter.write()
方法的JPEG参数上设置setOptimizeHuffmanTables(true)
的值。 - NikolaystoreImage
方法后,发送到服务器之前,您能否在 Android 端打开文件? - Ferran