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Thread: reading LSB of binarydata

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    Default reading LSB of binarydata

    i am able to change the content of text file to binary but now i have to select all the LSB of that binary data for further work how can i do that


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    Default Re: reading LSB of binarydata

    By LSB I assume you mean the Least Significant Byte of an int value.
    To get that byte, AND the int value with 0xFF.

    i am able to change the content of text file to binary
    I'm not sure what that means. A file is made up of bytes. A byte is made of 8 binary bits. There is not conversion needed when reading the bytes of a file. Can you explain and give an example.
    For example if the file contained these two bytes (in hex) 9591
    or in binary(1001 0101 1001 0001)
    what would the "changed" bytes look like?
    If you don't understand my answer, don't ignore it, ask a question.

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    Default Re: reading LSB of binarydata

    i mean to say i used byte[] b=filename.getBytes() to covert a text file into bytes now i need to change the LSB of that data

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    Default Re: reading LSB of binarydata

    Please define what LSB means and give an example.

    byte[] b=filename.getBytes() to covert a text file into bytes
    Is filename a String? What does it contain? How is that related to the contents of a text file?
    Are the lineend characters from the file included in the bytes that are obtained?
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    Default Re: reading LSB of binarydata

    i need to hide text into image file so for that purpose i have read a text file and converted into binary now how do i select LSB from that data and embedd into another LSB of image
    Define what you mean by LSB of data.

    Can you give an example?
    If you don't understand my answer, don't ignore it, ask a question.

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    Default Re: reading LSB of binarydata

    LSB means least significant Bit and i am doing a project on staganographyso for that purpose ineed to hide LSB of text data into the LSB of image file.SO i need to read LSB which i dont no so i need your help.plz

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    Default Re: reading LSB of binarydata

    hide LSB of text data
    What are you going to do with the other 7 bits? I assume the LSB is of a byte.

    If you read a file, byte by byte, and only save the LSB of each byte, then you would never be able to restore the full 8 bits of the byte having only saved the LSB.
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    Default Re: reading LSB of binarydata

    ok thanx for that sugestion then now what i have to do to hide whole text data into an image file just give me some hints so that i can work .

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    Default Re: reading LSB of binarydata

    To hide the whole text take the bits of each byte of the text and save them in the LSB of each byte in the image. First bit of first byte of text in LSB of first byte of image, second bit in second byte, third bit in third byte etc
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    Default Re: reading LSB of binarydata

    thanx
    to take each bits we have to read the bytes of the text files right but then howto save them in lsb of image?

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    Default Re: reading LSB of binarydata

    Here's a suggestion: Work with ByteArray streams for easier debugging.
    Write a method that takes two input streams and one output stream. Read the bits from one input stream, add its bits to the LSB of the other stream and write to the output stream.
    Then another method that takes an input stream (with the hidden text) and an output stream that gets the LSBs of the input stream, makes bytes and writes the bytes to the output stream.

    howto save them in lsb of image?
    Use the OR operator to set a bit in an int: 0b100 OR 0b001 gives 0b101
    Use the AND operator to clear a bit:
    0b011(input) AND 0b110 (the filter) gives 0b010 clearing the LSB

    NOTE: I'm using 0b to denote binary
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