{
  "checked": "2026-09-20",
  "encoder": "ffmpeg version 6.1.1-3ubuntu5 Copyright (c) 2000-2023 the FFmpeg developers",
  "method": "Executed the same commandFor/runFfmpeg functions as the Mediaivo tools. Checked file streams with ffprobe and decoded audio to 48 kHz mono float samples for sample peak and RMS. Not LUFS, true peak or a perceptual quality score.",
  "sources": [
    {
      "name": "Flower footage",
      "source": "https://github.com/mdn/shared-assets/blob/main/videos/flower.mp4",
      "credit": "MDN Web Docs contributors",
      "license": "CC BY-SA 2.5 under the MDN shared-assets content license",
      "licenseUrl": "https://github.com/mdn/shared-assets/blob/main/LICENSE.md",
      "changes": "Audio and metadata removed; H.264 video stream retained. Outputs re-encoded using the indicated Mediaivo presets. Video derivatives and extracted poster frames are offered under CC BY-SA 2.5."
    },
    {
      "name": "Alice’s Adventures in Wonderland, Chapter 1",
      "source": "https://librivox.org/alices-adventures-in-wonderland-by-lewis-carroll/",
      "download": "https://archive.org/download/alice_in_wonderland_librivox/wonderland_ch_01.mp3",
      "credit": "Lewis Carroll; read by Kristen McQuillin for LibriVox",
      "license": "Public-domain recording released by LibriVox",
      "licenseUrl": "https://librivox.org/pages/about-librivox/",
      "changes": "Excerpt 00:35–00:47, decoded to mono 48 kHz WAV, amplitude multiplied by 0.35 to prepare a quiet example. Outputs exported as MP3 at 125% and 200%."
    }
  ],
  "limitations": "One short nature clip and one prepared speech excerpt. These results do not represent every phone, speaker, codec, recording or scene. No claim of lossless compression, noise removal, loudness normalization or endorsement by the source creators.",
  "cases": [
    {
      "id": "flower-balanced",
      "input": "flower-source.mp4",
      "tool": "compress-video",
      "options": {
        "quality": "balanced"
      },
      "label": "Flower footage · Balanced",
      "output": "flower-balanced.mp4",
      "source": {
        "bytes": 964911,
        "sha256": "9f32dba823a4c36df93b683e3773019d4cec0267705ba1b0f542c7cd58306823",
        "duration": 5.005,
        "codec": "h264",
        "width": 960,
        "height": 540,
        "fps": "30000/1001"
      },
      "result": {
        "bytes": 243705,
        "sha256": "17c8e4fc1644d47aef1ec0ff700e8c74a8fe18afc98ec24d2092bd30a01a5fbc",
        "duration": 5.005,
        "codec": "h264",
        "width": 960,
        "height": 540,
        "fps": "30000/1001"
      },
      "poster": "flower-balanced.jpg"
    },
    {
      "id": "flower-smaller",
      "input": "flower-source.mp4",
      "tool": "compress-video",
      "options": {
        "quality": "smaller"
      },
      "label": "Flower footage · Smaller file",
      "output": "flower-smaller.mp4",
      "source": {
        "bytes": 964911,
        "sha256": "9f32dba823a4c36df93b683e3773019d4cec0267705ba1b0f542c7cd58306823",
        "duration": 5.005,
        "codec": "h264",
        "width": 960,
        "height": 540,
        "fps": "30000/1001"
      },
      "result": {
        "bytes": 122658,
        "sha256": "bea75037744ba87a59de8c2de9057dd18ca0d38a48888b9ce769a6438bd9b093",
        "duration": 5.005,
        "codec": "h264",
        "width": 960,
        "height": 540,
        "fps": "30000/1001"
      },
      "poster": "flower-smaller.jpg"
    },
    {
      "id": "speech-125",
      "input": "speech-quiet.wav",
      "tool": "change-audio-volume",
      "options": {
        "volume": "1.25"
      },
      "label": "Speech · 125%",
      "output": "speech-125.mp3",
      "source": {
        "bytes": 1152078,
        "sha256": "85b5f38de2c480b652f866f3e7123ecec2ab0f950b248ccc9177359762dda861",
        "duration": 12,
        "codec": "pcm_s16le",
        "sampleRate": 48000,
        "channels": 1,
        "peakDbfs": -15.44,
        "rmsDbfs": -31.42,
        "fullScaleSamples": 0
      },
      "result": {
        "bytes": 125325,
        "sha256": "4290ba84f432a2686defd95dfe0b0fee52559e27e133bb2c646b4b57d3e48151",
        "duration": 12.024,
        "codec": "mp3",
        "sampleRate": 48000,
        "channels": 1,
        "peakDbfs": -13.57,
        "rmsDbfs": -29.48,
        "fullScaleSamples": 0
      }
    },
    {
      "id": "speech-200",
      "input": "speech-quiet.wav",
      "tool": "change-audio-volume",
      "options": {
        "volume": "2"
      },
      "label": "Speech · 200%",
      "output": "speech-200.mp3",
      "source": {
        "bytes": 1152078,
        "sha256": "85b5f38de2c480b652f866f3e7123ecec2ab0f950b248ccc9177359762dda861",
        "duration": 12,
        "codec": "pcm_s16le",
        "sampleRate": 48000,
        "channels": 1,
        "peakDbfs": -15.44,
        "rmsDbfs": -31.42,
        "fullScaleSamples": 0
      },
      "result": {
        "bytes": 126429,
        "sha256": "d7924ec2d7f214d8126b681bf5975edef352297279fd9f6867281aefed9bf224",
        "duration": 12.024,
        "codec": "mp3",
        "sampleRate": 48000,
        "channels": 1,
        "peakDbfs": -9.39,
        "rmsDbfs": -25.4,
        "fullScaleSamples": 0
      }
    }
  ]
}