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image-processingjpegcodecimage-compressionjpeg2000

Can a JPEG2000 file have multiple fragment list box?


According to specification, The Fragment List box specifies the location, length and order of each of the fragments that, once combined, form a valid and complete data stream.

I want to know can single JPEG2000 file have multiple fragment list box?


Solution

  • Each Fragment table contains the location, length and order of the fragments needed to recontruct one codestream. Within a JPX file, you can include more than one codestream so, yes, you can have more than one fragment tables.

    From section M.11.3 of the JPEG 2000 Part 2 standard,

    M.11.3 Fragment Table box (superbox)

    A Fragment Table box specifies the location of one of the codestreams in a JPX file. A file may contain zero or more Fragment Table boxes. For the purpose of numbering codestreams, the Fragment Table box shall be considered equivalent to a Contiguous Codestream box. Fragment Table boxes shall be found only at the top level of the file; they shall not be found within a superbox.

    However, I don't think you can have more than one table for a single codestream.