Home Forums ActiveX components Xceed Zip for ActiveX & x64 About Fast Random Access in Zip File.

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    #41880 |

    Hello again. 🙂

    I run a company which develop online game, and I tring to use your library for storing Image and Texture data in one zip file.

    It need to extract certain file each time the game requested.

    However, zLib can make modify to access file with offset which is faster than xceedzip method, but zLib has slower function to extract compressed file than XceedZip.

    I suggest make some functions to store file offset, and access files with offset for faster random access.

    In game, there are over 5,000 files.

    If I use it with XceedZip, it takes too long time to wait to complete… 🙁

    The game request about small 300 files to extract to memory each time..

    So, I use zLib for it, but as you know I am a big fan of XceedZip. 🙂

    I hope I can use XceedZip with it.

    Please comment about this idea.

    Thanks a lot.

    P.S : How’s going v5.0’s ‘basepath’ bug?

    Imported from legacy forums. Posted by midmee (had 4027 views)

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    Hello midmee.

    If I’m right, I believe this zlib feature has nothing to do with zip files. Compressed data in a zip file uses the deflate compression algorithm, in a sequencial series of bytes. If you wish to decompress a single byte in a file, you need to decompress ALL preceeding bytes for that file. This is not a limitation of Xceed Zip, but a limitation of the zip file format.

    To decompress deflated data at a specific offset (as long as this offset is the beginning of a sequencial series of compressed data), you can use the Xceed Streaming Compression Library. But you’ll have to create yourself your own file format and manage offsets manually.

    I will take good note of your suggestion, but I cannot promise anything shortly!

    Imported from legacy forums. Posted by Martin (had 227 views)

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    Of course I have to make manage routine for that. 🙂 and I did it with zLib.

    But I could not make it with XceedZip, cuz, It doesn’t contain source code of it..

    Anyway, Is your streaming lib support access with offset?

    I didn’t look that streaming lib, but should I load all file data to memory if I use your streaming lib?

    Thanks.

    Imported from legacy forums. Posted by midmee (had 259 views)

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    Xceed Streaming Compression will allow you to do either of these:

    – Decompress from a file to memory, at a specific offset, for a specific compressed size.
    – Decompress from a file to a file, at a specific offset, for a specific compressed size.

    Take a look at both <A HREF=”http://doc.xceedsoft.com/products/Stream/index.htm?page=sources/readfile_method.htm”>ReadFile</A&gt; and <A HREF=”http://doc.xceedsoft.com/products/Stream/index.htm?page=sources/processfile_method.htm”>ProcessFile</A&gt; methods of the main XceedStreamingCompression class.

    Imported from legacy forums. Posted by Martin (had 168 views)

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    but… Xceed Streaming Compression not support password encryption…

    Imported from legacy forums. Posted by midmee (had 4984 views)

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