Compress Videos with FFmpeg and PHP‑FFMpeg: Command Line and Code Guide

FFmpeg Overview

FFmpeg is an open‑source suite for recording, converting and streaming audio/video. It includes libavcodec with many codecs written from scratch for portability and quality. It runs on Linux, Windows, macOS, and other operating systems.

Command‑line video compression

Original file size 3.8 MiB. The following command compresses it to ~644 KiB (≈83 % reduction).

ffmpeg -i "tinywan-input.mp4" -c:v libx264 -tag:v avc1 -movflags faststart -crf 30 -preset superfast "tinywan-output.mp4"

Explanation of key options: -c:v libx264 – use the H.264 encoder. -crf 30 – constant‑rate‑factor; higher values give smaller size at lower quality. -preset superfast – trade encoding speed for compression efficiency. -movflags faststart – relocate the MP4 moov atom to the file beginning for progressive streaming. -tag:v avc1 – set the video codec tag for compatibility.

Resulting file size: 644 KiB.

Online lossless compression tool

An online tool (rotato) can achieve a similar reduction without installing FFmpeg. The service is reachable at https://tools.rotato.app.

PHP‑FFMpeg library example

PHP‑FFMpeg requires PHP 8.0+. Install it via Composer: composer require php-ffmpeg/php-ffmpeg The script below creates an FFmpeg instance, opens a source video, resizes it to 640×480, synchronizes timestamps, and saves the output as an H.264 MP4 file.

<?php
declare(strict_types=1);
require_once __DIR__ . '/vendor/autoload.php';

/* 1. Initialize configuration */
$ffmpeg = \FFMpeg\FFMpeg::create([
    'ffmpeg.binaries'  => '/usr/bin/ffmpeg',
    'ffprobe.binaries' => '/usr/bin/ffprobe',
]);

/* 2. Open video file */
$video = $ffmpeg->open('/home/www/build/tinywan-input.mp4');

/* 3. Apply compression (resize) */
$video->filters()
      ->resize(new \FFMpeg\Coordinate\Dimension(640, 480))
      ->synchronize();

/* 4. Save compressed video */
$video->save(new \FFMpeg\Format\Video\X264(), '/home/www/build/ffmpeg/php-tinywan-output.mp4');

Resulting file size: 735 KiB.