Raspberry Pi 4: Chronicling the Desktop Experience – Viewing Photos – Week 23

Last Updated on August 20, 2020

This is a weekly blog about the Raspberry Pi 4 (“RPI4”), the latest product in the popular Raspberry Pi range of computers.

This week, I’m examining photo viewer software on the RPI4. The first thing to point out is that there’s lots of open source photo viewer software available for Linux. I’m not going to attempt any sort of wholesale survey from an RPI4 perspective. And I’ve not looked at the many open source photo managers even if they double as a photo viewer; I’ll cover them in a future edition of the blog.

Most of the images I work with use PNG and JPEG formats, although I’m also heavily dependent on WebP. PNG offers lossless compression. It supports alpha transparency, palette-based images, grayscale images, and full-color non-palette-based RGB or RGBA images. JPEG is another extremely popular image compression standard in the world, and the most widely used digital image format. Unlike PNG, JPEG uses lossy compression. WebP covers both bases, employing both lossy and lossless compression, and it’s a relatively modern format compared to JPEG and PNG. In a large scale study of 900,000 web images, WebP images were 39.8% smaller than JPEG images of similar quality.

GPicView

Raspbian’s default image viewer is GPicView (which is named “Image Viewer” in the Graphics section of the menu system).

GPicView offers the virtue of minimal library dependency, with only pure GTK+ being used. While you get the latest version (0.2.5) the program hasn’t seen any development for 4 years.

GPicView works well on the RPI4 for general usage. My main issues with GPicView are that it doesn’t support WebP, its customisation options are very limited, and it doesn’t support human-friendly “natural sorting”. Natural sort order is an ordering of strings in alphabetical order, except that multi-digit numbers are treated atomically, i.e., as if they were a single character. For example, z2.png is listed before z12.png. Given that the project is essentially abandoned, there seems little prospect of these limitations being resolved.

As GPicView doesn’t meet my requirements, I turned to our Group Test for Photo Viewers. The recommended free and open source image viewers are feh, gThumb and QuickViewer. As time is limited this week, I’ve focused my investigations on these 3 programs. Let’s start with gThumb.

gThumb

gThumb is an advanced image viewer and browser. It’s much more than an image viewer.

Unlike GPicView, gThumb supports WebP, human-friendly natural sorting, it’s under active development, and offers tons more functionality. It has many useful features, such as filesystem browsing, slide show, image catalogs, web album creation, camera import, image CD burning, batch file operations and quick image editing features like transformation and color manipulation. There’s lots of extensions that add even more functionality.

There’s a package in Raspbian. You get version 3.6.2, which was published back in September 2018. At the time of writing this blog, the latest version is 3.9.1. We’re missing out on a lot of development with the Raspbian package.

There’s a few steps needed to install the latest release, so I’ve set them out on a separate page.

How’s the performance of gThumb? Overall, I’m really impressed. The software runs really well on the RPI4. Even with a huge image collection, it’s very fast at navigating images.

It’s hard to make any memory comparisons with GPicView. But I can say that with a very small collection of 56 images, gThumb’s memory usage (version 3.6.2) was reported by ps_mem to be around 130MB of RAM. With version 3.9.1 the same test procedure reduced that memory usage to around 82MB of RAM.

feh

feh is notable for the highest score from the LinuxLinks Group Test. It’s text-based software, so if you’re hoping for a whizzy graphical interface, you’re going to be disappointed. Go with gThumb if a GUI is essential. But don’t dismiss command line software without giving it a try first.

feh is a very powerful and flexible image viewer. Like gThumb it supports a wide range of image formats, human-friendly natural sorting, and offers even more customization options. From my tests, it’s much quicker at navigating through huge image collections, and has a significantly lower memory footprint than gThumb. This will be important consideration when running the software on the 1GB or 2GB RAM models.

The Raspbian repositories host version 3.1.3 of feh which was released in February 2019. That’s a fairly recent release, but feh is under active development, with version 3.3 released in December 2019. I’ve detailed the steps you need to follow to compile the latest version separate page.

QuickViewer

QuickViewer is a highly regarded image viewer. It’s notable for drawing the imported image data on the screen with OpenGL.

Despite my best efforts, I wasn’t able to compile QuickViewer for the RPI4. And there isn’t a package in the Raspbian repositories. If you’re managed to compile QuickViewer, please explain how you were successful in the Comments box below. Your help would be very much appreciated. I’m certainly no expert at compiling, so you might have had better luck. As an aside, I also need to investigate the position regarding OpenGL on the RPI4 in more detail.

Summary

The default image viewer, GPicView, leaves a lot to be desired, missing key functionality. I strongly recommend you install gThumb and/or feh on your system. Both are excellent open source tools, gThumb will be your choice if you insist on a graphical user interface. But overall, the command-line feh offers everything I need, it’s lightning fast, and leaner.

Next page: Page 2 – Compiling gThumb

Pages in this article:
Page 1 – Main page
Page 2 – Compiling gThumb
Page 3 – Compiling feh

Read all my blog posts about the RPI4.

This blog is written on the RPI4.