binary-data

I accidentally committed some large binary data into some commits. Since then I've updated my .gitignore, and those files are no longer being committed. But I'd like to go back into the older commits and selectively prune out this data from the repository, removing a couple directories that should have been in .gitignore. I don't want to remove the commits themselves. How would I go about accomplishing this? My preferred method would be some way to retroactively apply the .gitignore rules to old commits... an answer that uses this method would also be pretty generally useful to others, since I

Specifically, what programs are out there and what has the highest compression ratio? I tried Googling it, but it seems experience would trump search results, so I ask. If file sizes could be specified accurate to the bit, for any file size N, there would be precisely 2^(N+1)-1 possible files of N bits or smaller. In order for a file of size X to be mapped to some smaller size Y, some file of size Y or smaller must be mapped to a file of size X or larger. The only way lossless compression can work is if some possible files can be identified as being more probable than others; in that scenario,

I want to store image documents in MongoDB. I am using java. Any links or suggestions would be appreciated. Edward83 For storing binary data like images you can use GridFS or implement your own realization; Download the driver and look at src/test/com/mongodb/gridfs/GridFSTest.java ;) Edit: you are lucky today! I made complete code for you;) Enjoy! package mongodb.testing.java; import com.mongodb.*; import com.mongodb.gridfs.*; import java.io.*; public class Main { public static byte[] LoadImage(String filePath) throws Exception { File file = new File(filePath); int size = (int)file.length();

I've seen a few questions here related to determining the similarity of files, but they are all linked to a particular domain (images, sounds, text, etc). The techniques offered as solutions require knowledge of the underlying file format of the files being compared. What I am looking for is a method without this requirement, where arbitrary binary files could be compared without needing to understand what type of data they contain. That is, I am looking to determine the similarity percentage of two files' binary data . To give a little more detail for you to work with, even though this is

I have a simple binary vector a which I try to translate into vector b using the R function cumsum . However, cumsum does not exactly return vector b . Here is an example: a <- c(1,0,0,0,1,1,1,1,0,0,1,0,0,0,1,1) b <- c(1,2,2,2,3,4,5,6,7,7,8,9,9,9,10,11) > cumsum(a) [1] 1 1 1 1 2 3 4 5 5 5 6 6 6 6 7 8 The problem is that whenever a 0 appears in vector a then the previous number should be increased by 1 but only for the first 0. The remaining ones are given the same value. Any advise would be great! :-) The trick is to use diff to mark the transitions: cumsum(as.logical(a+c(0,abs(diff(a))))) [1]

Let's say I have a string that contains a binary like this one "0110110101011110110010010000010". Is there a easy way to output that string into a binary file so that the file contains 0110110101011110110010010000010? I understand that the computer writes one byte at a time but I am having trouble coming up with a way to write the contents of the string as a binary to a binary file. Use a bitset: //Added extra leading zero to make 32-bit. std::bitset<32> b("00110110101011110110010010000010"); auto ull = b.to_ullong(); std::ofstream f; f.open("test_file.dat", std::ios_base::out | std::ios_base: