<p>FFmpeg is a powerful framework for manipulating audiovisual files. Unfortunately, it also has a steep learning curve, especially for users unfamiliar with the command line. This app helps users through the bash command generation process so that more people can reap the benefits of the FFmpeg library. </p>
<p>This project is very much a work in progress. Each button displays a form to help fulfill a popular user request. To use, click on the button and fill out the form. After clicking the Generate button, a command line will appear in the box below. That line can be copied and pasted into a Terminal, with the assumption that the video file is located in the same directory that the user currently is in.</p>
<p>For FFmpeg basics, check out their <ahref="https://www.ffmpeg.org/">official website.</a></p>
<p>For bash and command line basics, try the <ahref="http://cli.learncodethehardway.org/book/">Command Line Crash Course</a></p>
<spandata-toggle="modal"data-target=".example"><buttontype="button"class="btn btn-default"data-toggle="tooltip"data-placement="bottom"title="Displays information about a media file">Sample example</button></span>
<p>This is all about info! This is all about info! This is all about info! This is all about info! This is all about info! This is all about info! This is all about info! This is all about info! This is all about info! This is all about info! This is all about info! This is all about info! This is all about info! This is all about info! </p>
<spandata-toggle="modal"data-target=".one_thumbnail"><buttontype="button"class="btn btn-default"data-toggle="tooltip"data-placement="bottom"title="Export one thumbnail per video file">One thumbnail</button></span>
<spandata-toggle="modal"data-target=".multi_thumbnail"><buttontype="button"class="btn btn-default"data-toggle="tooltip"data-placement="bottom"title="Export many thumbnails per video file">Many thumbnails</button></span>
<p>This will grab a thumbnail every minute and output sequential png files.</p>
<ul>
<li>ffmpeg: calls the program</li>
<li>-i for input</li>
<li>-ss 00:00:20: seeks video file to 20 seconds into the video</li>
<li>-f image2: Forces the file format. image2 is an image file demuxer</li>
<li>-vf fps=fps=1/60: -vf is an alias for -filter:v, which creates a filtergraph to use for the streams. The rest of the command identifies filtering by frames per second, and sets the frames per second at 1/60 (which is one per minute).</li>
<li>out%d.png: Names the output file. The %d is a regular expression that adds a number (d is for digit) and increments with each frame (out1.png, out2.png, out3.png…)</li>
<spandata-toggle="modal"data-target=".pull_specs"><buttontype="button"class="btn btn-default"data-toggle="tooltip"data-placement="bottom"title="Pull specs from video file">Pull specs</button></span>
<p>ffmpeg documentation on ffprobe (full list of flags, commands, <ahref="https://www.ffmpeg.org/ffprobe.html">https://www.ffmpeg.org/ffprobe.html</a>) </p>
<spandata-toggle="modal"data-target=".pull_specs"><buttontype="button"class="btn btn-default"data-toggle="tooltip"data-placement="bottom"title="Join files together">Concatenate two or more files into a single file</button></span>
<p>This command takes two or more files of the same filetype and joins them together to make a single file. All that the program needs is a list specifying the files that should be concatenated. However, it only works if the files to be combined have the exact same codec and technical specifications. </p>
<p>ffmpeg documentation on concatenating files (full list of flags, commands, <ahref="https://trac.ffmpeg.org/wiki/Concatenate">https://trac.ffmpeg.org/wiki/Concatenate</a>) </p>
</div>
<divclass="well">
<ul>
<li>ffmpeg: calls the program</li>
<li>-f: forces the input file format</li>
<li>concat: ffmpeg’s concatenate command</li>
<li>-i: tells ffmpeg to expect input files</li>
<li>mylist.txt: a text file indicating the list of files to be concatenated. Should be formatted as:</li>
<li>-c copy: specifies the encoder for the output file by telling the program to copy the codecs of the original files and use them for the output file</li>
<li>[output]: desired filename for the output file</li>
<p>Made with ♥ at <ahref="http://wiki.curatecamp.org/index.php/Association_of_Moving_Image_Archivists_%26_Digital_Library_Federation_Hack_Day_2015">AMIA #AVhack15</a></p>