Lossless Format
An image file format that preserves all original pixel data through compression, allowing perfect reconstruction upon decoding.
A lossless format compresses image data without discarding any information, guaranteeing bit-perfect reconstruction. Key examples include PNG (Deflate), WebP Lossless (predictive + entropy coding), and TIFF (LZW/ZIP).
Compression ratios depend heavily on image content. Images with large uniform areas or smooth gradients can achieve over 90% reduction, while complex photographic textures typically compress only 20-50%. This is why photos favor lossy JPEG, while logos and screenshots benefit from lossless formats.
In editing workflows, saving intermediate files in lossless formats prevents generation loss from repeated encode-decode cycles. Lossy compression is applied only at the final export stage, preserving maximum quality throughout the creative process.