PDF417 can not decodifcar

[Angeles]

Hello!

I hope you can help me as I have had some problem while using zxing library, I'm using the client version .. some codes if I read them perfectly and to and others not and really need your help ... do not know if it's because I need to add reed-solomon .. if so could give me an example because I really do not know where to start I'm using C # .. and I wonder how it works and I could not decoficar an image PDF417 and really very urgent me solve my problem ... and I would also like to know if ay one size or resolution to be having the images to make them better their reading,,,

Thanks I attached the image I could not decode ..

thanks ..