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RE: Map reduce technique
Few points,
  Sequence File Layout
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From: Samir Kumar Das Mohapatra
Sent: 06 March 2013 11:21
Subject: RE: Map reduce technique

I think  you have to look the sequence file  as input format .

Basically, the way this works is, you will have a separate Java process that takes several image files, reads the ray bytes into memory, then stores the data into a key-value pair in a SequenceFile. Keep going and keep writing into HDFS. This may take a while, but you'll only have to do it once.


From: AMARNATH, Balachandar [mailto:[EMAIL PROTECTED]]
Sent: 06 March 2013 11:07
Subject: Map reduce technique


I am new to map reduce paradigm. I read in a tutorial that says that 'map' function splits the data and into key value pairs. This means, the map-reduce framework automatically splits the data into pieces or do we need to explicitly provide the method to split the data into pieces. If it does automatically, how it splits an image file (size etc)? I see, processing of an image file as a whole will give different results than processing them in chunks.

With thanks and regards
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