MKVToolNix (64-bit)

What's new in this version:

New features and enhancements:
- mkvmerge: AAC: implemented support for AAC with 960 samples per frame
- mkvmerge: identification: if the encoding/character set of a text subtitle track is known (e.g. because a byte order mark is present in the file), then it will be output during identification as the `encoding` property
- mkvmerge: WAV reader: added support for Wave64 files
- mkvmerge, mkvpropedit, MKVToolNix GUI (chapter editor): added support for chapters in WebM files that is spec-compliant by removing all tag elements not supported by the WebM spec
- mkvpropedit: added support for tags in WebM files that is spec-compliant by removing all tag elements not supported by the WebM spec
- MKVToolNix GUI: multiplexer: if the encoding/character set of a subtitle track cannot be changed, the GUI will deactivate the "subtitle character set" drop-down box and ignore changes to it when multiple tracks are selected. Additionally, if the track's encoding is known and cannot be changed (e.g. due to a byte order mark in the file), that encoding will be selected in the drop down box automatically. Both changes signal to the user that she doesn't have to take care of the encoding herself
- MKVToolNix GUI: chapter editor: added a function to the "additional modifications" dialog for calculating and setting the end timestamps
- MKVToolNix GUI: changed the shortcuts for switching between the various tools from `Alt+number` (e.g. `Alt+1` for the multiplexer tool) to Ctrl+Alt+number` in order to avoid clashing with Windows' input method for arbitrary characters (pressing and holding `Alt` and typing the codepoint on the number pad)
- MKVToolNix GUI: added a "Window" menu and entries with shortcuts for selecting the next (`Ctrl+F6`) respectively previous tab (`Ctrl+Shift+F6`) in the current tool
- MKVToolNix GUI: on Windows the GUI will now determine the default font to use by querying Windows for the default UI/message box font instead of using the hardcoded `Segoe UI`. This might fix issues such as #2003 (unverified). translations: added a Romanian translation of the programs by Daniel (see AUTHORS)

Bug fixes:
- mkvmerge: AVC/h.264 parser: fixed wrong frame order & timestamp calculation in certain situations when SPS (sequence parameter sets) or PPS (picture parameter sets) change mid-stream
- mkvmerge: HEVC/h.265 parser: fixed wrong frame order & timestamp calculation in certain situations when SPS (sequence parameter sets) or PPS (picture parameter sets) change mid-stream
- mkvmerge: MPEG-1/-2 video: the "remove stuffing bytes" feature introduced in v5.8.0 (feature request #734) was broken. In a lot of situations it did not detect the end of a slice correctly and removed 0 bytes that were actually part of the slice structure. Often there were no visual problems as decoders were able to ignore such errors, but in other cases there are visual artifacts upon decoding. As detecting the slice end properly requires parsing the whole slice structure, this feature has been removed again
- mkvmerge: MPEG PS reader: fixed mkvmerge trying to handle an "end" code the same way as a "program stream map" code
- mkvmerge: MPEG TS reader: mkvmerge won't emit warnings if the system's iconv` library doesn't support the ISO 6937 character set
- mkvmerge: when appending fails the error message details (e.g. "the number of channels differs: 1 and 2") were often not output
- MKVToolNix GUI: multiplex tool: implemented a workaround for a crash that could occur during drag & drop if at least one of the columns is hidden
- MKVToolNix GUI: multiplex tool: appended tracks can no longer be enabled selected for multiplexing) if the track they're going to be appended to is not enabled
- MKVToolNix GUI: multiplex tool: if the GUI is set to ensure unique output file names, it will now verify that right before starting to multiplex/adding the job to the queue, too
- MKVToolNix GUI: fixed the total progress reverting to 0% instead of staying at 100% when all jobs have finished. This was introduced by the attempt at fixing the computation of the value of total progress bar for multiple jobs running. Fixes #2005. configure: fixed DocBook detection if `/bin/sh` is `dash`

Build system changes:
- Boost: the minimum required version has been bumped to 1.49.0. Earlier releases fail to build on my current systems and will therefore not be supported anymore. configure: when looking for the "nlohnmann JSON" include files configure will now try the path "nlohmann/json.hpp" first, "json.hpp" second (only "json.hpp" was tried before). If neither is found, the copy included in the MKVToolNix sources will be used