You are viewing a plain text version of this content. The canonical link for it is here.
Posted to dev@tika.apache.org by "Marco Quaranta (JIRA)" <ji...@apache.org> on 2013/02/15 11:49:12 UTC

[jira] [Updated] (TIKA-1085) PDF header and mime detection

     [ https://issues.apache.org/jira/browse/TIKA-1085?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]

Marco Quaranta updated TIKA-1085:
---------------------------------

    Issue Type: Improvement  (was: Bug)
    
> PDF header and mime detection
> -----------------------------
>
>                 Key: TIKA-1085
>                 URL: https://issues.apache.org/jira/browse/TIKA-1085
>             Project: Tika
>          Issue Type: Improvement
>          Components: mime
>    Affects Versions: 1.3
>            Reporter: Marco Quaranta
>            Priority: Minor
>              Labels: detection, header, mime, pdf
>
> I've found some PDF files Tika recognizes as application/octet-stream.
> These files differs from regularly identified PDF having a different header: the %PDF-N.n string isn't at the beginning (zero offset) of the file but in the first 1024 bytes.
> PDF reference states that "The first line of a PDF file shall be a header consisting of the 5 characters  %PDF–  followed by a version 
> number of the form 1.N, where N is a digit between 0 and 7" (http://tinyurl.com/8vnzm3c "p. 7.5.2 File Header"). 
> Looking further at implementation notes by Adobe (http://tinyurl.com/cbqpb24 p. 3.4.1 File Header) I've discover that: "Acrobat viewers require only that the header appear somewhere within the first 1024 bytes of the file"
> What do you think about a PDF magic match with an offset 0:1024?
> <match value="%PDF-" type="string" offset="0:1024"/>
> Thank you,
> Marco

--
This message is automatically generated by JIRA.
If you think it was sent incorrectly, please contact your JIRA administrators
For more information on JIRA, see: http://www.atlassian.com/software/jira