Images and photos can often be compressed to reduce their storage space requirements. If used with care, image compression can reduce file sizes of images and photos anywhere between 10% to 90%, without a visible loss in quality.
Webmasters for instance need to make sure the images they post on their websites are optimized, to avoid prolonged loading times for their visitors.
But compressing images can also be beneficial for other computer users, for instance before sending the latest holiday photos to friends and family.
Caesium is a lightweight image compressor that comes with all the bells and whistles one would expect.
The Open Source software needs to be installed before it can be used. Images are then loaded into the interface by clicking on the Add Files button in the main menu.
Each image is listed with its name, current file size and full path on the local computer system.
The lower half of the screen contains the image compression settings that are applied to the images during compression. The program will convert them by default into jpg images with a quality setting of 80%. Both the output format and the quality can be changed easily on the screen.
Additional options include the selection of an output directory, and an (optional) suffix.
A click on the preview button renders a preview image and displays it beneath the original image in the program interface.
This way it is possible to compare the original image with the compressed image, to see if there is the need for fine tuning the image compression settings.
Caesium displays the new size, ratio and quality next to the original image information. It is important to set the image container size to original under View > Image Container Size. The default image size is to small to compare the image's quality thoroughly.
A click on the compress button compresses the images in the queue, and either saves them in the same directory as the input images, or in the output directory location.
- Resize your pictures up to 90% preserving the file format. The software use an intelligent file compressing method.
- Batch processing. Compress in a few second as pictures as you like.
- Most common file format are supported. (JPG, BMP, PNG, GIF, WMF)
- Easy preview, with a twin picture box that display the final result with a button.
- Picture-by-picture compression level. You can set every single compression level at every picture.
- Compression level can be set with an easy slider.
- Drag&Drop. Drop your pictures directly into the list.
- Rename all files with a custom suffix.
Caesium does an excellent compression job most of the time. The standard output settings seem to work really well, and usually do not generate an output image of noticeable lower quality than the original. Depending on the original image, it can happen that the new compressed size of the image is in fact larger than the original size.
The Open Source software Caesium is available for download at the developer's website over at Sourceforge.
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