Changed distutils.spawn.fine_executable() to shutil.which() (ref #32).

Converted os.path to pathlib and all #! lines to python3 (ref #32).

Converted all print statements to functions for Python 3 (ref #32).

• Added --copy-audio and --copy-video options to disable all additional stream processing (reducing audio channels, etc.). ...

• Removed -n for --no-normalise.
• Added configurable audio and video codecs via --audio-codec and --video-codec options.
• Fixed bug where the final punch out time for an odd number of timestamps was incorrectly calculated.

• Rewrote shellquote() to ignore things like command-line switched and executable paths. Also only execute the catch-all regex when no other regexes match (closes #27). ...

• Switched to double-quoting of strings because that makes it easier to handle single quotes in strings (which is more likely than double quotes).
• Added more test cases.

• Updated regular expressions in ShellCommand.shellquote() to catch the weirder edge cases (closes #26).

• Deleted leftover development debugging output. ...

• Added code to resize frame inputs to the size of the smallest video segment where applicable (closes #23). Still need to add resizing for differently sized video inputs.

• Redesigned FFprobeCommand to retrieve media file entries in JSON format for easier extraction and processing. ...

• Changed default of --input-prefix to “.”.
• Added check that the input prefix actually exists.
• Ensured that the segments list variable actually exists when cleanup happens.

• Ensured that prefix isn’t added if input filename is “^”. ...

• Rearranged display of frame processing progress bar.
• Better handling of frame segment processing errors:
    – Added SegmentException.
    – Checked all subprocess exit status values.
• Moved cleanup() call into finally clause.
• Added Segment._temp_files_list to make deletion of temporary files more predictable, and eliminate inadvertent deletion of original source files for PDF frame inputs.
• Refactored segment temporary file generation (closes #22).

• Added progress bars for all long-running operations (closes #18). ...

• Added new ProgressBar class.
• Switched from subprocess to pexpect for running shell commands.
• Added general shell quoting for debugging output of commands.
• Rewrote the way command strings and argument lists are generated.
• Removed “-loglevel error” from ffmpeg commands to enable capturing progress information (pexpect doesn’t echo the output anyway).

• Ensured that audio/video output options and filters are only included when there actually is an audio/video stream (closes #19). ...

• Rearranged exception handling on main() so that a KeyboardInterrupt is caught no matter where you are in the process.

• Shifted -truecolor setting from the outer image sequence into the parenthesised image sequence, to fix weird coloured box that were appearing on certain pages.

• Refactored input/output options variables and methods from FFmpegCommand into ShellCommand, so that all subclasses can use them. ...

• Enhanced ConvertCommand to do more intelligent processing of PDF frames of varying sizes and aspect ratios.

• When appending a concat filter, check that the segments list actually contains something.

• Added white background and removed transparency for PDF to PNG image conversions.

• Moved shell command classes into separate module.