Trim each read from bam file

Question

[SSK]

Hi. I'm trying to trim each reads in bam. I want to crop not whole reads but each read, so I don't think trimBam is good way.

How can I do this ?

[ATpoint]

Your question lacks any details. What do you want to trim? What is not whole reads but each read? Please give representative examples.

[SSK]

Sorry, my words was not enough. I want to do bootstrap method. Thus I sampled randomly from bam file, and made subsampled.bam. On the top of that, I want to crop read randomly from subsampled.bam.

Ex.

[pre bam]

read1 150b

read2 150b

read3 150b

[trimmed bam]

read1 100b (trimmed 50b)

read2 150b (trimmed 0b)

read3 20b (trimmed 130b)

Do you understand what I mean?