How to compress and uncompress image file on linux?

Use the following command :

1.UNCOMPRESS :


uncompress the image and extract the archive into /tmp/initrd

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#gzip -dc < /tmp/initrd.img | cpio -idv ----- or ---- zcat -d image|cpio -idv ---- 2COMPRESS :


a) Generate a list of files to be made into a new cpio archive.

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#find . -depth -print | cpio -ovc > ../custom-initrd.cpio
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b) gzip the cpio image:

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#gzip -9 ../custom-initrd.cpio
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tc..