compression

问题 I am using the LZString.compressToBase64 function of lz-string.js and need to decompress/compress the data on the server side. The obvious solution seems to be lz_string_csharp but I am concerned about this statement: If you use just the regular Javascript 'compress' function then depending on the data in the string, it will not decompress correctly on the C# side. However, if you are using the 'compress' function built into this C# version, then you should be ok to use the regular

问题 I am using the LZString.compressToBase64 function of lz-string.js and need to decompress/compress the data on the server side. The obvious solution seems to be lz_string_csharp but I am concerned about this statement: If you use just the regular Javascript 'compress' function then depending on the data in the string, it will not decompress correctly on the C# side. However, if you are using the 'compress' function built into this C# version, then you should be ok to use the regular

问题 I have a script which saves and caches images with intervention, and it's working 100% However i am trying to work out how i can add 75% compression to jpg & png files, but i don't know i would apply it in this situation. I didn't think PNG files could be compressed apart from software which does it, so im not really sure if its the same thing? There is an example of compression here: http://image.intervention.io/api/save /* ////////////////////// IMAGES //////////////////////// */ Route::get

问题 I want to emulate the functionality of gzcat | tail -n. This would be helpful for times when there are huge files (of a few GB's or so). Can I tail the last few lines of such a file w/o reading it from the beginning? I doubt that this won't be possible since I'd guess for gzip, the encoding would depend on all the previous text. But still I'd like to hear if anyone has tried doing something similar - maybe investigating over a compression algorithm that could provide such a feature. 回答1: No,

问题 I want to emulate the functionality of gzcat | tail -n. This would be helpful for times when there are huge files (of a few GB's or so). Can I tail the last few lines of such a file w/o reading it from the beginning? I doubt that this won't be possible since I'd guess for gzip, the encoding would depend on all the previous text. But still I'd like to hear if anyone has tried doing something similar - maybe investigating over a compression algorithm that could provide such a feature. 回答1: No,

问题 I need to compress portions of our application's network traffic for performance. I presume this means I need to stay away from some of the newer algorithms like bzip2, which I think I have heard is slower. 回答1: You can use Deflater/Inflater which is built into the JDK. There are also GZIPInputStream and GZIPOutputStream, but it really depends on your exact use. Edit: Reading further comments it looks like the network taffic is HTTP. Depending on the server, it probably has support for

问题 I have huge data in hadoop archive .har format. Since, har doesn't include any compression, I am trying to further gzip it in and store in HDFS. The only thing I can get to work without error is : harFile.coalesce(1, "true") .saveAsTextFile("hdfs://namenode/archive/GzipOutput", classOf[org.apache.hadoop.io.compress.GzipCodec]) //`coalesce` because Gzip isn't splittable. But, this doesn't give me the correct results. A Gzipped file is generated but with invalid output ( a single line saying

问题 If I have a folder with a bunch of images, how can I tar ONLY the images and not the folder structure leading to the images without having to CD into the directory of images? tar czf images.tgz /path/to/images/* Now when images.tgz is extracted, the contents that are extracted are /path/to/images/... How I can only have the images included into the tgz file (and not the three folders that lead to the images)? 回答1: I know you can use --strip-components when untarring although I'm not sure if

问题 I wrote this function to remove the most significant bit in every byte. But this function doesn't seem to be working the way I wanted it to be. The output file size is always '0', I don't understand why nothing's been written to the output file. Is there a better and simple way to remove the most significant bit in every byte?? 回答1: In relation to shift operators, section 6.5.7 of the C standard says: If the value of the right operand is negative or is greater than or equal to the width of

问题 I wrote this function to remove the most significant bit in every byte. But this function doesn't seem to be working the way I wanted it to be. The output file size is always '0', I don't understand why nothing's been written to the output file. Is there a better and simple way to remove the most significant bit in every byte?? 回答1: In relation to shift operators, section 6.5.7 of the C standard says: If the value of the right operand is negative or is greater than or equal to the width of