File Formats Overview
This is an introduction and reference to the file formats that are available for saving image captures in Snagit. This tutorial doesn't go in depth on each format; instead, the goal is to introduce the strengths and weaknesses of each format to help you make informed decisions when choosing a file format.
The SNAG file format is used to store Snagit projects with unflattened vector objects and an undo history. This is the only format that allows you to edit vector objects like arrows and callouts after saving.
SNAG files can't be viewed outside of Snagit, making this file format unsuitable for sharing or displaying images. It is, however, the best format for archiving captures (and is the format used behind the scenes when Snagit autosaves your captures in the Library).
Tip: It's often useful to save a copy of your image in the SNAG file format as well as your chosen final file format in case you need to make changes later.
The PNG file format is great for sharing images in documents, presentation slides, and online. What makes PNG so great? Here's a list.
- It's lossless. That means that when the file is compressed, it has the exact same quality as an uncompressed image. This means that PNG files look exactly like the screen you captured.
- It supports full and partial transparency with 32 bit color depth.
- Can be viewed in almost all file viewers, graphics programs, and web browsers. (The only exception is Internet Explorer 6-- it doesn't display transparency information in PNG files.)
Aside from the Internet Explorer 6 issue (which is becoming less relevant as support for Internet Explorer 6 fades), the only possible drawback to PNG is file size. PNG's lossless compression results in smaller files than other lossless formats (like BMP), but still produces files larger than a lossy format like JPG. A slightly larger file is the trade-off for a lossless image.
The JPG file format is found all over the Internet and is the default used by many digital cameras. JPG is a lossy format, which means that the compression process used when saving the file degrades the quality of the image. This results in blocky, uneven colors and shapes in your image.
This lossy compression works best in photographs, but tends to look bad with the solid colors and square shapes found in most screen captures.
So, when should you use JPG? Some programs or websites might require JPGs. Other times, file size is a concern. Because it is a lossy format, JPG often results in the smallest file size for saved images. Unless you're really counting the kilobytes, PNG is almost always a better choice over JPG when it comes to screen capture images.
The GIF file format is an older image file format, but is still in use. GIF supports a limited amount of animation, which is one of the reasons it's still useful. GIF only supports 256 colors per image. This limited color palette can lead to color banding on images with lots of color or gradients.
GIF supports full color transparency only. A single color in the palette of 256 colors can be treated as a transparent color.
Computer interfaces have become more visually complex, which means 256 colored paletted formats like GIF no longer accurately reflect what you see on your screen. The limited colors result in a smaller file size, but the drop in quality is a steep trade-off.
The BMP file format is a lossless format, but unlike the lossless PNG format, BMP does not compress file size. This can result in a very large files.
Unless you have a specific need for a BMP file, the lossless and compressed PNG format is better for your images. Transparency in BMP files is not supported in Snagit.
The TIF file format is often used for document scanning. TIF is not a common format on the PC, and is used mostly by applications taking advantage of the ability to add metadata to the file (TIF stands for Tagged Image Format). TIFs saved in Snagit don't have any particular advantage over a file format like PNG. But, TIF is there if you need it (and if you don't, you can safely ignore it).
Snagit captures can be saved as a PDF. The most popular reason to save in the PDF format is when you use the "Keep Web links active" option. This captures hyperlink information and saves that as part of your capture. When saved as a PDF, the links that appear in your image are active links that point to their original destinations.
Once saved as a PDF, the PDF file cannot be re-opened in Snagit.
The SWF file format is used to create a file that contains active links and hotspots. The only problem is that by default, SWF files aren't associated with a viewing program on most computers. Viewing a SWF file requires the viewer to open it in a web browser or Flash player. Unless you plan on hosting the SWF on the web or embedding it in a presentation slide or email, SWF files often cause confusion for your viewers.
Once saved as a SWF, the SWF file cannot be re-opened in Snagit.
For almost all screen captures, the recommended file type is PNG. This the default save type in Snagit, and for good reason. Its lossless compression gives great quality, reasonable file size, and supports features like transparency.
For archiving captures, the SNAG file is the format of choice. It saves your editing history and allows you to make changes to vector objects on the canvas.