Overview
This page describes techniques you can use to reduce the disk space required by the files that comprise your site. While disk space is plentiful on your own PC, you may want or need to reduce the disk space required by your site in order to fit within a disk space quota on a web server.
You can determine the size of your site using the Utilities > Output Folder > Show Size... command. That command sums the size of the files under the Output (-o) folder. Do not change any files in that folder in an attempt to reduce the size of the site. Instead, follow the directions here to change the configuration of the site or change the size of files that GedSite uses to make the site.
People
The number of people included in your site determines how many HTML pages will be created by GedSite. Unless your site includes a lot of people—a hundred thousand people or more—the number of people will not be a significant factor in the disk space required by the site. HTML files are small relative to image files, so image files are usually the most important factor.
The number of people per page is an important factor. Setting this value to a low number, like one, will dramatically increase the number of person pages and thus the number of HTML files required by the site. I strongly recommend that all GedSite users set People per Page to 25 or higher.
Images
For most GedSite users, the amount of disk space required by a site is mostly determined by the number and size of its image files. Images included in the site fall into these categories:
- Exhibit images — These are attached to records in your genealogy database and are sometimes called media items.
- Image User Item images — These are added to custom pages as content items.
- Background images, icons, and other images — These are included in the site via the Theme or customizations you make. These are rarely an important factor.
On this page, image size refers to the number of bytes in the image file whereas image dimensions refer to the height and width of the image in pixels.
The image format, image dimensions, and image compression ratio are factors that influence an image's file size.
- Image format — Web image formats are JPEG (AKA JPG), PNG, and GIF.
The JPEG format is highly compressable and is usually the best choice for photographs or for high-resolution scanned document images. JPEG uses a "lossy" compression method meaning that some fine details will be lost as part of saving an image to the JPEG format. For photographs, this is typically not a significant issue except at the highest compression ratios. JPEG file size is determined by the image dimensions and the compression ratio. Compression ratio is sometimes determined by an image quality setting: high quality = low compression, low quality = high compression.
The PNG format is less compressable than JPEG and is usually the best choice for small icons on scanned images with fine detail, such as small text. PNG file size is determined by the image dimensions and, for the "8bit PNG" format, where colors are limited to a pallette with 256 or fewer colors, redcuing the size of the color pallette will reduce the size of the PNG file.
The GIF format is very similar to the PNG format described above.
- Image dimensions — On the web, the only important image dimension factor is the width and height of the image in pixels.
Web browsers ignore the "pixels per inch" setting for an image, so even though an 1200px by 1200px with 300 pixels per inch will by 4 inches by 4 inches when printed, the image will be closer to 12 inches by 12 inches on a web page. (The actual size on a monitor will vary according to several factors.)
I recommend using images that are a maximum of 1200 pixels wide, and many images can be smaller than that. Many visitors to your site will be using smartphones and other mobile devices that have small displays/monitors that are only a few hundred pixels wide. Others will be using PC monitors, and those will be a couple thousand pixels wide, but they may not have their browser windows maximized and they may have their monitors scaled: at a 150% scaling factor, a 1200 x 1200 image will use 1800 x 1800 pixels on the visitor's monitor.
When an image exceeds the width or height of the browser window, the browser may either resize the image to fit the window or leave the image as-is which means the user will have to scroll to see all of the image.
To provide the best experience for your visitors, reduce image dimensions as much as possible while maintaining good image quality.
- Image compression — Image compression refers to techniques used to reduce the number of bytes in an image file. The techniques vary by image format; see the Image format discussion above.
Image File Size Reduction
To save disk space on a web server, you should consider reducing the size of image files. Any image file that is larger than 500KB is a good candidate.
- When you manipulate images, you should always keep the original.
- Reduce the dimensions of high-resolution images. So, for example, if you have a JPEG file that is 2400px by 3000px, you should resize it, probably down to 1200px by 1500px or smaller. When choosign the optimal dimensions, consider file size, image quality/usability, and the visitor experience.
- Increase the compression ratio for JPEG images. Some photo editors use the opposite terminology and call this “decreasing the quality”. By incresaing compression, or reducing quality, the file size will drop. You can judge for yourself how increasing the compression ratio affects the quality. In many cases, you won’t be able to tell the difference.
- For image exhibits—image files attached to records in your genealogy database—you may want to keep the high-resolution version for use in reports printed from your genealogy software. To keep those images, but use smaller files in your web site, use GedSite's Alternate Folder feature.
- Use GedSite's Optimize Image Files feature.