Raspberry Pi 4: Chronicling the Desktop Experience – Viewing PDFs – Week 9

Last Updated on April 8, 2020

Charts

The ratings apply to the software provided in Raspbian’s repository. A few of the software in the repository lag behind the latest version although the majority are the latest release or a sufficiently recent release not to pose an issue. I’ve summarized the position in this regard in the final page of this week’s blog.

Let’s start off with features. Almost all the software has support for zooming, basic navigation, and a full screen option. Extra credit is given for features like thumbnails, tabs, the ability to read encrypted files, continuous and multi-page layouts, useful keyboard shortcuts, night mode, and lots more besides. A surprising number omit search functionality which is a significant omission from any perspective. I also give credit to programs that offer multi-format support rather than focus solely on PDFs.

While features are important, the responsiveness of the viewer is equally as important. Most of the programs start up promptly, with MuPDF offering lightening speed, whereas pdfpc is a real slowcoach. Startup time isn’t that important. More significant is navigation speed i.e. how fluid the experience of navigating around the document. Any delay in advancing to the next page is a real turn-off.

Factors that weigh heavily on the ratings include the responsiveness of navigating between pages, the speed of searching a PDF, as well as other specifics like keyboard shortcuts to jump to a specific page.

Many of the programs navigate between pages extremely quickly. The pre-installed qpdfview is fast at navigating pages, but it’s definitely not the quickest; okular, MuPDF are expeditious. This helps make reading PDFs a pleasurable experience.

In fact the only ones that are too slow for my liking are apvlv, pdfpc, and ePDFview, the latter suffers from terrible lags. At least searching PDFs with apvlv is reasonably quick.

Many of the programs are pretty sluggish at searching PDFs. qpdfview’s search functionality is a mite disappointing although enabling parallel search execution from the Settings panel makes a big improvement. And it’s search functionality is much quicker than Evince even though Evince has the edge on rendering pages. Others are painfully slow. Ones that search at a pedestrian speed include okular, ePDFview, and katarakt although the latter also usefully performs operations (such as rendering pages and searching) in parallel. Quite a few of the programs lack search functionality which lowers their navigational abilities.

The two charts indicate the PDF viewers that warrant my recommendation.

Another important factor to consider is the memory usage. The chart below shows the memory usage of each program loaded with a fairly hefty PDF, and performing an identical series of actions on that file.

For okular, I show memory consumption for the default memory setting. okular has 4 memory settings (Low, Normal (default), Aggressive, and Greedy. In Greedy move everything is kept in memory with all pages preloaded.

Some of the other applications also offer low memory settings which aren’t reflected in the chart. For example, pqiv has a –low-memory flag which reduces memory usage by disabling optimizations such as preloading the next and previous image.

As you can see, qpdfview uses a fairly hefty chunk of memory which will be an important consideration for users of the 1GB RAM and 2GB RAM model. All of them use significantly less memory than viewing a PDF using Chromium.

Next page: Page 3 – Software Information

Pages in this article:
Page 1 – qpdfview
Page 2 – Charts: Features, Navigation, Memory Usage
Page 3 – Software Information

Read all my blog posts about the RPI4.

This blog is written on the RPI4.