Version 53.0.0 "Fool's Gold" 2021-01-30

New features and enhancements

• mkvmerge: AVI reader: added support for reading the video aspect ratio from the video properties header (vprp chunk) if present and setting the display dimensions accordingly. Implements #2993.
• mkvmerge: MP4 reader: for h.264/AVC tracks that don't have an AVCConfigurationBox (avcC atom) in their sample description (stsd) atom or whose avcC atom contains no content mkvmerge will now re-derive the AVCConfigurationBox from the bitstream. Implements #2995.
• mkvextract: mkvextract will now check if any of the destination file names is the same as the source file name and abort with an error if that's the case. Implements #3001.
• MKVToolNix GUI: when querying the user for a file name for saving things (e.g. multiplexer settings or an attachment in the header editor), the automatically suggested file name will now be based on the situation-specific file names (e.g. the destination file name for multiplexer settings or the attachment's name when saving an attachment in the header editor) instead of the directory's name. Implements #3012.
• MKVToolNix GUI: multiplexer: when deriving track languages from file names the GUI will now select the right-most match instead of the left-most one. For example, "La.vie.en.rose.(fr).srt" will now be detected as French (fr) instead of English (en). Implements #3013.
• MKVToolNix GUI: preferences: the items in the "pre-defined …" lists can now be renamed by double-clicking with the mouse or pressing the F2 key.

Bug fixes

• mkvmerge: stretching chapter timestamps with --chapter-sync now works correctly with floating point values including fractions of floating point numbers (e.g. 12.3/45.67). The tooltips in the GUI have been adjusted accordingly. Fixes #3002.
• mkvmerge: MPEG 1/2 video handling: the "default duration" header field was often half the value it actually should be, resulting in all video frames having an explicit block duration with the correct value. This has been fixed with a patch by Tom Yan.
• mkvmerge: MPEG 1/2 video handling: the data stored in Codec private and Codec state doesn't contain extensions other than sequence & sequence display extensions anymore. Fix by Tom Yan.
• mkvmerge: tag handling: when remuxing a Matroska file with the --no-track-tags, existing SOURCE_ID track tags are now skipped, too.
• MKVToolNix GUI: multiplexer: the drop-down boxes with pre-defined track names now follow the order set in the preferences instead of sorting the entries alphabetically. Fixes #2999.

Version 52.0.0 "Secret For The Mad" 2021-01-04

New features and enhancements

• MKVToolNix GUI: job queue: the maximum number of jobs to run concurrently can now be increased in the preferences. The default remains at 1. Implements #2984.
• MKVToolNix GUI: the GUI will now add a context-specific default extension to file names selected for saving on platforms that don't add one itself (e.g. GNOME). For example, when saving multiplexer settings the extension .mtxcfg will be added. Implements #2983.
• MKVToolNix GUI: added an option to the preferences for the window to stay on top of other windows. Implements #2967.

Bug fixes

• mkvextract: h.265/HEVC extraction: the code for skipping extraction of prefix SEI NALUs in the first frame was skipping two bytes too few, resulting in broken processing of all following bytes. Patch by Mike Chen.
• libEBML: the optional, bundled version of libEBML was updated to v1.4.1.

Build system changes

• libEBML v1.4.1 is now required due to a bug in libEBML that caused pointers to just-freed memory being returned to the caller under certain invalid data constellations, causing use-after-free errors in all of MKVToolNix's programs. Fixes #2989.