compression

In the uncompressed situation I know I need to read the wav header, pull out the number of channels, bits, and sample rate and work it out from there: (channels) * (bits) * (samples/s) * (seconds) = (filesize) Is there a simpler way - a free library, or something in the .net framework perhaps? How would I do this if the .wav file is compressed (with the mpeg codec for example)? Jan Zich You may consider using the mciSendString(...) function (error checking is omitted for clarity): using System; using System.Text; using System.Runtime.InteropServices; namespace Sound { public static class

I was thinking about compression, and it seems like there would have to be some sort of limit to the compression that could be applied to it, otherwise it'd be a single byte. So my question is, how many times can I compress a file before: It does not get any smaller? The file becomes corrupt? Are these two points the same or different? Where does the point of diminishing returns appear? How can these points be found? I'm not talking about any specific algorithm or particular file, just in general. Nosredna For lossless compression, the only way you can know how many times you can gain by

I have list of gzip files: file1.gz file2.gz file3.gz Is there a way to concatenate or gzipping these files into one gzip file without having to decompress them? In practice we will use this in a web database (CGI). Where the web will receive a query from user and list out all the files based on the query and present them in a batch file back to the user. With gzip files, you can simply concatenate the files together. Per the gzip RFC , A gzip file consists of a series of "members" (compressed data sets). [...] The members simply appear one after another in the file, with no additional

I am trying to compress video taken with the users camera from UIImagePickerController (Not an existing video but one on the fly) to upload to my server and take a small amount of time to do so, so a smaller size is ideal instead of 30-45 mb on newer quality cameras. Here is the code to do a compression in swift for iOS 8 and it compresses wonderfully, i go from 35 mb down to 2.1 mb easily. func convertVideo(inputUrl: NSURL, outputURL: NSURL) { //setup video writer var videoAsset = AVURLAsset(URL: inputUrl, options: nil) as AVAsset var videoTrack = videoAsset.tracksWithMediaType

I have a large amount of data to move using two PHP scripts: one on the client side using a command line PHP script and other behind Apache. I POST the data to the server side and use php://input stream to save it on the web-server end. To prevent from reaching any memory limits, data is separated into 500kB chunks for each POST request. All this works fine. Now, to save the bandwidth and speed it up, I want to compress the data before sending and decompress when received on the other end. I found 3 pairs of functions that can do the job, but I cannot decide which one to use: gzencode /

I have a large array with a range of integers that are mostly continuous, eg 1-100, 110-160, etc. All integers are positive. What would be the best algorithm to compress this? I tried the deflate algorithm but that gives me only 50% compression. Note that the algorithm cannot be lossy. All numbers are unique and progressively increasing. Also if you can point me to the java implementation of such algorithm that would be great. We have written recent research papers that survey the best schemes for this problem. Please see: Daniel Lemire and Leonid Boytsov, Decoding billions of integers per