feat: Add support for ffmpeg via snap package, requires ability to specify custom ffmpeg binary names if required

closes: https://github.com/KrumpetPirate/AAXtoMP3/issues/200

AAXtoMP3

@@ -35,6 +35,8 @@ audibleCli=0                # Default off, Use additional data gathered from mkb
 aaxc_key=                   # Initialize variables, in case we need them in debug_vars
 aaxc_iv=                    # Initialize variables, in case we need them in debug_vars
 ffmpegPath=                 # Set a custom path, useful for using the updated version that supports aaxc
+ffmpegName=ffmpeg           # Set a custom ffmpeg binary name, useful tailoring to local setup
+ffprobeName=ffprobe         # Set a custom ffprobe binary name, useful tailoring to local setup
 library_file=               # Libraryfile generated by mkb79/audible-cli
 
 # -----
@@ -92,6 +94,10 @@ while true; do
     --author          ) authorOverride="$2";                                            shift 2 ;;
                       # Ffmpeg path override
     --ffmpeg-path     ) ffmpegPath="$2";                                                shift 2 ;;
+                      # Ffmpeg name override
+    --ffmpeg-name     ) ffmpegName="$2";                                                shift 2 ;;
+                      # Ffprobe name override
+    --ffprobe-name    ) ffprobeName="$2";                                                shift 2 ;;
                       # Command synopsis.
     -h | --help       ) printf "$usage" $0 ;                                            exit ;;
                       # Standard flag signifying the end of command line processing.
@@ -218,11 +224,11 @@ fi
 
 # Use custom ffmpeg (and ffprobe) binary ( --ffmpeg-path flag)
 if [ -n "$ffmpegPath" ]; then
-  FFMPEG="$ffmpegPath/ffmpeg"
-  FFPROBE="$ffmpegPath/ffprobe"
+  FFMPEG="$ffmpegPath/${ffmpegName}"
+  FFPROBE="$ffmpegPath/${ffprobeName}"
 else
-  FFMPEG="ffmpeg"
-  FFPROBE="ffprobe"
+  FFMPEG="${ffmpegName}"
+  FFPROBE="${ffprobeName}"
 fi
 
 debug_vars "ffmpeg/ffprobe paths" FFMPEG FFPROBE

README.md

@@ -59,6 +59,8 @@ bash interactiveAAXtoMP3 [-a|--advanced] [-h|--help]
 * **--use-audible-cli-data** Use additional data got with mkb79/audible-cli. See [below](#audible-cli-integration) for more info. Needed for the files in the `aaxc` format.
 * **--audible-cli-library-file** or **-L** Path of the library-file, generated by mkb79/audible-cli (`audible library export -o ./library.tsv`). Only available if `--use-audible-cli-data` is set. This file is required to parse additional metadata such as `$series` or `$series_sequence`.
 * **--ffmpeg-path**  Set the ffmpeg/ffprobe binaries folder. Both of them must be executable and in the same folder.
+* **--ffmpeg-name**  Set a custom name for the ffmpeg binary. Must be executable and in path, or in custom path specified by --ffmpeg-path.
+* **--ffprobe-name**  Set a custom name for the ffprobe binary. Must be executable and in path, or in custom path specified by --ffmpeg-path.
 
 ## Options for interactiveAAXtoMP3
 * **-a** or **--advanced** Get more options to choose. Not used right now.
@@ -174,6 +176,12 @@ You can then tell AAXtoMP3 to use the compiled binaries with the `--ffmpeg-path`
 You need to specify the folder where the ffmpeg and ffprobe binaries are. Make sure
 they are both executable.
 
+If you have snapd installed, you can also install a recent version of 4.4 from the edge channel:
+```
+snap install ffmpeg --edge
+```
+In this case you will need to confiure a custom path _and_ binary name for ffprobe, `--ffmpeg-path /snap/bin/ --ffprobe-name ffmpeg.ffprobe`.
+
 __Fedora__
 
 Fedora users need to enable the rpm fusion repository to install ffmpeg. Version 22 and upwards are currently supported. The following command works independent of your current version: