Most of you'd know the basic differences between JPEG and GIF files. Especially, if you are a photographer, it is a must to understand the difference between lossless and lossy image formats. Using a different type of image compression from these may damage your file’s quality in a miserable way. And, we’ll also tell you whether it’s a good option to convert from a lossy image type into a lossless one.
What are Lossless Formats?
If an image file type preserves all of the file’s original data, it’s a lossless format. RAW image types are typical examples of it. If you save an image in RAW format, it’ll keep all the optical data along with meta information in that image, resulting in a large image file.
Apart from RAW files, there are several image types in lossless formats including PNG, BMP, etc.
Lossy Formats Explained
Lossy image formats remove some of the image data from the file producing a much smaller file. JPEG is a popular example. Even on JPEG, there is a variable quality setting that controls its lossy levels. So, you can have a much smaller JPEG file compromising much of its quality.
TIFF, and GIF, are some of the famous lossy image formats other than JPEG.
Comparison Between Lossy and Lossless
| Factors | Lossy Compression | Lossless Compression |
| Compression Ratio | High compression ratios | Lower compression ratios |
| File Size | Smaller file size | Larger file size |
| Quality | Loss of image quality | No loss of image quality |
| Multimedia Files | Suitable for images, audio, and video with minor quality loss | Not suitable as it struggles to compress multimedia files. |
| Reversibility | Irreversible | Fully reversible |
Now comes the real question: Is It Good to Convert from Lossy to Lossless?
Technically, a lossless algorithm looks for recurring patterns in files to compress and replace each occurrence with a short abbreviation. As a result, file sizes will get reduced.
Conversely, lossy algorithms store color-coded information in a lower resolution as compared to the original image so as to result in a substantial size reduction of files.
You know that you’ll remove some part of the image when you convert a lossless format to a lossy one. But, if you go on converting a lossy format to a lossless one, you won’t get any of the lost data back. Say, for example, you’re converting a JPEG file to a PNG file. You may get a larger PNG file after conversion. But the quality of the file won’t be different from that of the JPEG file. That’s why you should not convert lossy images into lossless types.
Frequently Asked Questions
How does compression affect an image?
When an image is going through the compression process the redundant data like colors, pixels, or metadata are removed and several filters are applied to reduce the size of the image while maintaining the visual aspect of the image.
Is PDF format lossy or lossless?
PDF is a lossless image format as it is designed to preserve the original content.
Is JPEG XL lossless or lossy?
JPEG XL is an image compression format that supports both lossless and lossy compression.
