Types of input Amazon EMR can accept

The default input format for a cluster is text files with each line separated by a newline (\n) character, which is the input format most commonly used.

If your input data is in a format other than the default text files, you can use the Hadoop interface InputFormat to specify other input types. You can even create a subclass of the FileInputFormat class to handle custom data types. For more information, see http://hadoop.apache.org/docs/current/api/org/apache/hadoop/mapred/InputFormat.html.

If you are using Hive, you can use a serializer/deserializer (SerDe) to read data in from a given format into HDFS. For more information, see https://cwiki.apache.org/confluence/display/Hive/SerDe.