file-format

问题 I'm a newbie in programming bmp files and i checked this web site to learn about bmp header.. http://www.daubnet.com/en/file-format-bmp it seems that the header of a bmp file is 54 bytes. Using paint, i created a simple 10x10 image, and i saved it in 24 bits. so according to simple math, the file size should be 10*10*3 + 54 = 354 bytes. but hex editor and file explorer returned a size of 374 bytes. So i have a difference of 20 bytes, and i don't know why. could you tell me why please? thanks

问题 I'm a newbie in programming bmp files and i checked this web site to learn about bmp header.. http://www.daubnet.com/en/file-format-bmp it seems that the header of a bmp file is 54 bytes. Using paint, i created a simple 10x10 image, and i saved it in 24 bits. so according to simple math, the file size should be 10*10*3 + 54 = 354 bytes. but hex editor and file explorer returned a size of 374 bytes. So i have a difference of 20 bytes, and i don't know why. could you tell me why please? thanks

问题 I'm following the python challenge riddles, and I now need to analyse a wav file. I learn there is a python module that reads the frames, and that these frames are 16bit or 8bit. What I don't understand, is what does this bits represent? Are these values directly transformed to a voltage applied to the speakers (say via factoring)? 回答1: The bits represent the voltage level of an electrical waveform at a specific moment in time. To convert the electrical representation of a sound wave (an

问题 I need to parse a file which is in the following format: "General" { "Description" = "Some Text" "Version" = "4" "ProjType" = "1" } "Configurations" { "Mice" { "BuildOutputs" = "BuildProject" "OutputFile" = "output.txt" } "Men" { "BuildOutputs" = "BuildProject" "ChangedSinceLastBuilt" = "True" } } Does anyone have any idea what file format this is? If it's well known then there could be already made libraries to help parse it. It appears to be similar to JSON but instead of colons it uses

问题 My understanding of the Git pack file format is something like: Where the table is 32-bits wide, and the first three 32-bit words are the pack file header. The last row of 32 bits are the first 4 bytes of an entry. As I understand it, the size of the entry is specified by consecutive bytes with the MSB set, followed by compressed data. In the first byte whose MSB is not set, is the MSB part of the compressed data, or is it a gap? If it's part of the compressed data, how can you guarantee that

问题 Anyone knows how to load a .AI file (Adobe Illustrator) and then rasterize/render the vectors into a Bitmap so I could generate eg. a JPG or PNG from it? I would like to produce thumbnails + render the big version with transparent background in PNG if possible. Ofcause its "possible" if you know the specs of the .AI, but has anyone any knowledge or code to share for a start? or perhaps just a link to some components? C# .NET please :o) Code is most interesting as I know nothing about reading

问题 I am new to ORC file. I went through many blogs, but didn't get clear understanding. Please help and clarify below questions. Can I fetch schema from ORC file? I know in Avro, schema can fetched. How it actually provides schema evolution? I know that few columns can be added. But how to do it. The only I know, creating orc file is by loading data into hive table which store data in orc format. How ORC files index works? What I know is for every stripe index will be maintained. But as file is

问题 I have a few questions: Why was a.out replaced by ELF ? What were the major flaws in the a.out format that led to the raise of ELF file format? Earlier core dumps were based on a.out, but now they are based on ELF. What are the various advantages provided by ELF? 回答1: The a.out format forced shared libraries to occupy a fixed place in memory. If you wanted to distribute an a.out shared library, you had to register its address space. This was good for performance but it didn't scale at all.

问题 Wikipedia has an excellent description of the ZIP file format, but the "central directory" structure is confusing to me. Specifically this: This ordering allows a ZIP file to be created in one pass, but it is usually decompressed by first reading the central directory at the end. The problem is that even the trailing header for the central directory is variable length. How then, can someone get the start of the central directory to parse? (Oh, and I did spend some time looking at APPNOTE.TXT

问题 I'm trying to write my own vce reader (Visual Cert Exam). But .vce is a binary format. Does exist any way to decode the format? Otherwise, does exist any other equivalent open format? 回答1: So... this question is rather old and I have recently (a few hours over 2 days of investigation so far) been working on this same issue. The .vce file contains a sqlite database file which is encrypted using AES-256-CBC. It can apparently be read using the libsqlcipher library which is partly what has