formats

I've been doing some reading on file formats and I'm very interested in them. I'm wondering what the process is to create a format. For example, a .jpeg, or .gif, or an audio format. What programming language would you use (if you use a programming language at all)? The site warned me that this question might be closed, but that's just a risk I'll take in the pursuit of knowledge. :) You do not need a programming language to write the specification for a file format, although a word processor might prove to be a handy tool. Basically, you need to decide how the information of the file is to be

How to convert all audio formats to mp3 in php Using ffmpeg can be helpful. For details http://ffmpeg.org/ at first you install ffmpeg on your system. (it is free), then in PHP you can call the ffmpeg to convert any audio file to mp3 using the system command like this: <?php $output = system("ffmpeg parameters..."); echo $output; ?> see the ffmpeg documentation for examples how to call ffmpeg. 来源： https://stackoverflow.com/questions/11840650/how-to-convert-all-audio-formats-to-mp3-in-php

When any TGraphic descendant registering its own graphic file format with a class procedure TPicture.RegisterFileFormat(), they're all stored in Graphics.FileFormats global variable. Too bad that FileFormats variable is not in the "interface" section of "Graphics.pas", so I can't access it. I need to read this variable to implement a special filter for my file-list control. Can I get that list without manual fixing the Graphics.pas's source code? Remy Lebeau You are working with a file-list control, and presumably thus a list of filenames. If you don't need to know the actual TGraphic class