【发布时间】:2019-10-03 20:02:03
【问题描述】:
我在 Android 中使用此代码向图像添加文本:
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;
}
我将文件发送到我的服务器,我收到一个输入流,我创建一个文件,我对其进行缩放,并使用缩放后的图像创建一个新文件:
ImageWriter.write(metadata, new IIOImage(image, null, metadata), param);
我得到一个 IIOException:
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 android 调用 drawTextToBitmap(),我不会收到该错误。
如果有人可以帮助我...谢谢
编辑:这是我用来从文件中获取元数据的方式
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);有效,但它会重置所有元数据,我想像 gps 位置一样保留它们......
【问题讨论】:
-
服务器端是否异常?
-
尝试在传递给
ImageWriter.write()方法的jpeg参数上设置valuesetOptimizeHuffmanTables(true)。 -
服务器端异常,如果 setOptimizeHuffmanTables(true) 结果文件会丢失其元数据,如 gps ..
-
如果可能的话,贴出相关的服务器代码。
-
我已经发布了服务器代码:ImageWriter.write(metadata, new IIOImage(image, null, metadata), param);,如果我不在 android 上调用 drawTextToBitmap,它可以工作,如果我调用android 上的 drawTextToBitmap 然后我在 ImageWriter.write(metadata, new IIOImage(image, null, metadata), param); 上有一个 IIOException 服务器端;