MKVToolNix 48

# Version 34.0.0 "Sight and Seen" 2019-05-18
## Bug fixes
* mkvmerge: all subtitle frames are now treated as key frames in order to fix
wrong data in source files. Fixes #2541.
* mkvmerge: AV1: fixed frame timestamp calculation when reading bitstreams
that lack timing information from IVF files. Fixes #2553.
* mkvmerge: Matroska reader: fixed an infinite loop that could happen with
large video frames and applied timestamp files due to too much data being
buffered at the wrong time. Fixes #2550.

## New features and enhancements
* mkvmerge: JSON identification: the "codec name" track property will be
output as `codec_name`. The JSON schema has been bumped to v12 for this
change.
* MKVToolNix GUI: job queue: added a new type of action to execute after job
completion: deleting source files for of multiplexer jobs. As this is a
destructive operation, the action is disabled by default. Implements #869
and #2570.
## Bug fixes...

## New features and enhancements
* mkvmerge: mkvmerge now allows appending AV1, VP8, VP9, H.264/AVC and
H.265/HEVC tracks whose pixel dimensions differ. Implements #2582.
## Bug fixes...

## New features and enhancements
* mkvextract: chapters, tags & cue sheets will now be written to standard
output if no file name is given, same as if `-` is given as the file name.
* MKVToolNix GUI: job queue: added a new setting in the preferences' "job
queue & job status" section that, when enabled, will cause the GUI to remove
all output files created by jobs that are either aborted by the user or that
end in an error. Implements #2614.
## Bug fixes...

## New features and enhancements
* mkvmerge: Blu-ray: when reading an MPLS playlist mkvmerge will look up and
use chapter names from the Blu-ray's "track/chapter names" meta data if it
exists. Part of the implementation of 2486.
* mkvmerge: MP4 reader: if present, cover art images (the
`meta.udta.ilist.covr` atom) will be converted into attachments.
* MKVToolNix GUI: multiplexer: when adding a playlist from a Blu-ray disc, the
disc library meta data will be parsed, and the biggest thumbnail, if
present, will be added as a new attachment with name `cover.jpg` (extension
depends on thumbnail's extension). Implements #2644.
* MKVToolNix GUI: multiplexer: when adding a playlist from a Blu-ray disc, the
title from the disc library meta data will be set as the new file title if
the disc library meta data contains one & no title has been set yet.
* MKVToolNix GUI: multiplexer: the automatically generated destination file
name will now be based on the file title if one is set at that point. This
works in conjunction with the title being said from the Blu-ray disc library
meta data.
* MKVToolNix GUI: chapter editor: when reading chapters from an MPLS playlist
the GUI will look up and use chapter names from the Blu-ray's "track/chapter
names" meta data if it exists. Part of the implementation of 2486.
* MKVToolNix GUI: Windows: added a dark mode that's enabled when Windows 10's
dark mode is turned on.
* translations: added a Bulgarian translation of the programs & the man pages
by Симеон Цветков (see `AUTHORS`).
## Bug fixes...

## New features and enhancements
* mkvmerge: MP4 reader: added support for BMP covert art images.
* MKVToolNix GUI: multiplexer: added an option to disable deriving the
destination file name from the file title. Implements #2648.
* MKVToolNix GUI: multiplexer: the content of the "stereoscopy" combo box has
been simplified making the box's minimum width much smaller, allowing the
user to resize the GUI's whole window to a much smaller width.
* MKVToolNix GUI: multiplexer: whenever the user changes the "aspect ratio" or
"display dimensions" controls, the corresponding radio button will be
activated automatically. Implements #2651.
* MKVToolNix GUI: Windows: added a setting in the preferences to disable the
GUI's dark color mode even if Windows's app color mode is set to
dark. Implements #2646.
* MKVToolNix GUI: Windows: replaced the dark mode introduced in v39 with
another dark mode that's less wasteful with space between widgets.
## Bug fixes...

## New features and enhancements
* mkvmerge: Matroska reader: Vorbis tracks: stream comments (aka Vorbis
comments) will be converted to Matroska attachments (for cover arts) and
Matroska track tags (for other comments). Additionally the stream comments
will be removed from Vorbis headers.
* mkvmerge: MP4 reader: added support for reading Opus audio from MP4
files. Part of the implementation of #2673.
* mkvmerge: MP4 reader: added support for reading VP9 video from MP4
files. Part of the implementation of #2673.
* mkvmerge: Ogg reader: Vorbis, Opus & VP8 streams: stream comments (aka
Vorbis comments) will be converted to Matroska attachments (for cover arts)
and Matroska track tags (for other comments). Additionally the stream
comments will be removed from Vorbis headers.
* mkvmerge: WAV reader: added support for reading RF64 files.
* MKVToolNix GUI: multiplexer: the list of predefined track names is now split
up into three lists, one for each track type (audio, video &
subtitles). Part of the implementation of #2654.
* MKVToolNix GUI: multiplexer: when trying to add thumbnails for a Blu-ray the
GUI will determine the thumbnail's pixel size from the thumbnail files if
the XML file doesn't contain that information. This works for JPEG and PNG
files. Implements #2674.
* MKVToolNix GUI: general: line edits & combo boxes will now have a "clear
text" button appear whenever they're not empty. Part of the implementation
of #2654.
* MKVToolNix GUI: update check: the dialog showing the latest news & version
information states explicitly where the links take the user (the MKVToolNix
`NEWS.md` file and YouTube respectively).
## Bug fixes...