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imagegraphicsheader

What is the header size of png, jpg/jpeg, bmp, gif and other common graphics format?

I have search in google. I found something here, http://paulbourke.net/dataformats/bmp/ , but I can't understand the size of header.

Reading some webpages I got confused. http://en.wikipedia.org/wiki/JPEG

Can anyone give the correct information of header about all these format?

Solution

  • PNG file contains 8-bytes header.

    JPEG file (see specification) contains 2-bytes header (SOI) followed by series of markers, some markers can be followed by data array. Each type of marker has different header format. The bytes where the image is stored follows SOF0 marker (10-bytes length). However, between JPEG header and SOF0 marker there can be other segments.

    BMP file contains 14-bytes header.

    GIF file contains at least 14 bytes in its header.