What Is Lossless Compression?
Lossless compression reduces file size without discarding any data, allowing the original file to be perfectly reconstructed from the compressed version.
Lossless Compression explained
Lossless compression reduces file size by finding and encoding patterns and redundancies in data without discarding any information. The original data can be perfectly reconstructed from the compressed file, bit for bit. Common algorithms include DEFLATE (used in PNG and ZIP), LZW (used in GIF and TIFF), and FLAC for audio. Lossless compression typically achieves 2:1 to 3:1 compression ratios for images and 2:1 for audio, which is significantly less than lossy methods but guarantees zero quality loss. It is essential for archival, medical imaging, professional photography, and any use case where data integrity is non-negotiable.
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Related terms
Lossy compression reduces file size by permanently discarding data deemed less perceptible, trading some quality for significantly smaller files.
A codec (coder-decoder) is an algorithm that compresses and decompresses audio or video data, determining the quality, file size, and compatibility of media files.
Bit depth determines how many distinct colors or tones each pixel (or audio sample) can represent, directly affecting quality and file size.
TIFF (Tagged Image File Format) is a flexible, high-quality image format used in publishing, photography, and archival for lossless image storage.