why does picture quality changes after downloading from website?
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I am writing parsing code to extract images from website. Its based on taking <img> tags and getting the source link of the image.

If we take website BBC as example ([news article][1]), the source of the first picture they show is ([link][2]) but if i open that link directly, the quality of the images changes drastically. 

I am not able to understand how BBC shows a good quality of the picture with same link and how i am not able to get same quality BBC shows by downloadin

Can you tell me how i can get the same quality picture by downloading ?

Many Thanks


  [1]: http://www.bbc.co.uk/news/world-asia-pacific-18844149
  [2]: http://news.bbcimg.co.uk/media/images/61576000/jpg/_61576956_015313589.jpg