Image formats for presentations JPEG vs. PNG vs. GIF
So far I’ve told you about where to find beautiful images for your presentations, but we have not mentioned that not all the image files are the same.
I would like to share with you the three formats I use in my presentations to understand what the main differences are and when to use one over another.
JPEG – Joint Photographic Experts Group
Image format commonly used, widely used in the world of photography.
It has a compression algorithm that reduces the size of an image, on average, 1/10 of the original size.
In summary, the JPEG compression algorithm is based on the fusion of pixels that resemble each other. For this reason, it is a file that significantly reduces the quality of the image with the advantage of weight and, therefore, can’t be used to store images because, once compressed, it can’t go back.
In presentations, JPEG is good for photographs, but it is not good for graphics (lines, typography, drawings, etc.) because it tends to granulate the edges.
Finally, JPEG is an image that lives on a level, so it will always have a white background that could create the problems that are seen above when we talk about transparent and non-transparent images.
PNG – Portable Network Graphics
This image format is based on the LSW compression algorithm which, unlike JPEG compression, works without losing the initial information.
Therefore, a PNG file compresses the image without losing the details of the original, which may not be displayed on the screen, but which can certainly be recovered by graphically editing the file.
For presentations, the most interesting feature of PNG is that it supports the transparent background layer, so you can get photos with transparent background thanks to this format, which I know from now on that you will adopt as the only format of your presentations.
I use PNG every time I present a logo in SlideMaster, work with the icon (unless you can use them in SVG or EPS, of course – see the definitive guide for the use of icons in PowerPoint), or images that should have a transparent background.
In conclusion, the PNG does not present a risk of blurry images over time.
GIF – Graphical Interchange Format
Very low quality image format that allows you to store 8 bits per pixel for a total of 256 colors per image compared to 16 million JPEGs that reach the limits of what the human eye can see.
The GIF was born as a specific format for the web in the 80s. Therefore, taking into account the needs related to the band, it made his work perfectly given the minimum weight.
The reason why everyone knows this format is because it allows you to store multiple images in sequence by creating small animations that are often used in social networks.
Do not think of GIF as a poor loop animation, because you can get a really interesting work.
If, when inserting a GIF, in PowerPoint you do not see that it comes to life, do not worry, it’s normal. In fact, PowerPoint reads animated GIF only in presentation mode.
Therefore, always check the slide show mode where you placed the GIF to see if it works correctly.
GIFs can usually be downloaded from Google Images or from portals such as giphy.