David Kleiner

Microsoft has added HEIF support to Windows 10 in the meantime, however support needs to be downloaded separately. To be able to open HEIF in JPEGView, download the HEIF package from Microsoft (download will be offered when you first try opening HEIF in the Windows Photo Viewer), then add the HEIF extension to JPEGView.ini, key FilesProcessedByWIC: FilesProcessedByWIC=.wdp;.hdp;.jxr;.heic You may also set JPEGView as default program to open HEIF - do this using the standard Windows mechanism (Open...

Not reproducible. Starting 30 instances, total CPU load is 1%. CPU load of JPEGView processes is 0 %. Maybe Windows OS has issues on your system (related to OneDrive??). You can turn off scanning current folder in INI with: ReloadWhenDisplayedImageChanged=false

JPEGView uses GDI+ to read GIF files. GDI+ is part of the operating system, i.e. Windows. JPEGView thus can read exactly the GIFs Windows can read. With my Windows 10, I can open the animated GIF you provided above without problems. Maybe Microsoft had a bug in former Windows versions.

If you volunteer, you can try now with VS 2017 community edition and try to find out which files are missing and how to get them. I can then include that into a HOWTO file, including links where to find the missing files. As I said, directly including has license issues.

I moved the main project to VS 2017 now. Be aware that I am using the professional edition. For the community edition, I fear that some ATL headers are missing. Due to licensing issues, I cannot include them. You need to borrow these files from a professional version or from somewhere in the internet...

Moved to VS2017. A VS 2013 version still exists.

1.0.37 is released today.

JPEGView 1.0.37 released