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From "AMARNATH, Balachandar" <BALACHANDAR.AMARN...@airbus.com>
Subject RE: Map reduce technique
Date Wed, 06 Mar 2013 05:54:23 GMT
Thanks for the mail,

Can u please share few links to start with?


Regards
Bala

From: Samir Kumar Das Mohapatra [mailto:dasmohap@adobe.com]
Sent: 06 March 2013 11:21
To: user@hadoop.apache.org
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.

Regards,
Samir.

From: AMARNATH, Balachandar [mailto:BALACHANDAR.AMARNATH@airbus.com]
Sent: 06 March 2013 11:07
To: user@hadoop.apache.org
Subject: Map reduce technique

Hi,

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
Balachandar




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