feat: initial release of transcode.sh v1.0.0

Batch transcode helper for media files using ffmpeg. Encoding parameters
are supplied by user-defined preset files (shell snippets that set an
`ffargs` array) stored under
${XDG_CONFIG_HOME:-$HOME/.config}/transcode.sh/presets/.

Key capabilities:
- Probes input codec and pixel format via ffprobe; derives an output
  pixel format that preserves chroma subsampling and bit depth.
- Per-user and per-invocation codec skip lists to leave already-encoded
  files untouched.
- Atomic in-place replacement: encodes to a temp file in the same
  directory, then renames on success.
- --only-if-smaller: discard the result if it is larger than the
  original.
- --saving: append filename, original/new sizes and percentage saved to
  a log file after each successful encode.
- --dry-run, --verbose, --quiet, --nice and --continue flags.
- Respects the NO_COLOR standard.
- Script hardening: strict PATH, safe IFS, errtrace, nounset, pipefail.

Also included:
- Man page (transcode.sh.1)
- Bash completion script (transcode.sh.bash-completion)
- README.md
- .gitmessage commit message template

License: BSD-3-Clause

1 files changed, 149 insertions, 0 deletions

diff --git a/transcode.sh.bash-completion b/transcode.sh.bash-completion
new file mode 100644
index 0000000..ce153dd
--- /dev/null
+++ b/transcode.sh.bash-completion
@@ -0,0 +1,149 @@
+# bash completion for transcode.sh
+# Install to:
+#   /etc/bash_completion.d/transcode.sh
+# or source manually:
+#   source transcode.sh.bash-completion
+#
+# Each option that takes an argument is supported in all three forms:
+#   short          -f list.txt
+#   long space     --encodefile list.txt
+#   long equals    --encodefile=list.txt
+
+_transcode_sh() {
+    local cur prev words cword
+    _init_completion || return
+
+    local -r preset_dir="${XDG_CONFIG_HOME:-$HOME/.config}/transcode.sh/presets"
+
+    # ---------------------------------------------------------------------------
+    # Helper: collect preset names from the preset directory
+    # ---------------------------------------------------------------------------
+    _transcode_presets() {
+        local presets=()
+        if [[ -d "$preset_dir" ]]; then
+            local f
+            while IFS= read -r f; do
+                f="${f##*/}"   # basename
+                f="${f%.sh}"   # strip .sh extension
+                presets+=("$f")
+            done < <(find "$preset_dir" -maxdepth 1 -name '*.sh' -type f 2>/dev/null)
+        fi
+        printf '%s\n' "${presets[@]}"
+    }
+
+    local codecs='h264 hevc av1 vp8 vp9 mpeg2video mpeg4 mjpeg theora'
+    local nice_vals='0 5 10 15 19'
+
+    # ---------------------------------------------------------------------------
+    # Handle --option=VALUE: cur contains the entire "--opt=val" token.
+    # Strip the "opt=" prefix and delegate to the appropriate completer.
+    # This must be checked before the $prev dispatch below.
+    # ---------------------------------------------------------------------------
+    case "$cur" in
+        --encodefile=*)
+            cur="${cur#*=}"
+            _filedir
+            return
+            ;;
+        --saving-file=*)
+            cur="${cur#*=}"
+            _filedir
+            return
+            ;;
+        --nice=*)
+            cur="${cur#*=}"
+            COMPREPLY=( $(compgen -W "$nice_vals" -- "$cur") )
+            return
+            ;;
+        --skip-codec=*)
+            cur="${cur#*=}"
+            COMPREPLY=( $(compgen -W "$codecs" -- "$cur") )
+            return
+            ;;
+        --preset=*)
+            cur="${cur#*=}"
+            COMPREPLY=( $(compgen -W "$(_transcode_presets)" -- "$cur") )
+            return
+            ;;
+    esac
+
+    # ---------------------------------------------------------------------------
+    # Handle VALUE after short form (-f, -N, -S, -p) and
+    # long space form (--encodefile, --nice, --saving-file, --skip-codec, --preset).
+    # $prev is the option word, $cur is the value being typed.
+    # ---------------------------------------------------------------------------
+    case "$prev" in
+        -f|--encodefile)
+            _filedir
+            return
+            ;;
+        -N|--nice)
+            COMPREPLY=( $(compgen -W "$nice_vals" -- "$cur") )
+            return
+            ;;
+        --saving-file)
+            _filedir
+            return
+            ;;
+        -S|--skip-codec)
+            COMPREPLY=( $(compgen -W "$codecs" -- "$cur") )
+            return
+            ;;
+        -p|--preset)
+            COMPREPLY=( $(compgen -W "$(_transcode_presets)" -- "$cur") )
+            return
+            ;;
+    esac
+
+    # ---------------------------------------------------------------------------
+    # Complete option names themselves.
+    # For options that accept an argument we list both the bare long form
+    # (--nice) and the equals form (--nice=) so the user can choose their
+    # preferred style.  compopt -o nospace is applied when the sole match
+    # ends with '=' to avoid an unwanted trailing space in that case.
+    # ---------------------------------------------------------------------------
+    case "$cur" in
+        --*)
+            local longopts='
+                --continue
+                --encodefile
+                --encodefile=
+                --dry-run
+                --nice
+                --nice=
+                --saving
+                --saving-file
+                --saving-file=
+                --skip-codec
+                --skip-codec=
+                --only-if-smaller
+                --preset
+                --preset=
+                --help
+                --quiet
+                --verbose
+                --version
+                --color
+                --no-color
+            '
+            COMPREPLY=( $(compgen -W "$longopts" -- "$cur") )
+            # Suppress the trailing space when the only completion ends with '='
+            [[ ${#COMPREPLY[@]} -eq 1 && "${COMPREPLY[0]}" == *= ]] \
+                && compopt -o nospace
+            return
+            ;;
+        -*)
+            local shortopts='-c -f -n -N -s -S -l -p -h -? -q -v --'
+            COMPREPLY=( $(compgen -W "$shortopts" -- "$cur") )
+            return
+            ;;
+    esac
+
+    # ---------------------------------------------------------------------------
+    # Default: complete positional FILE arguments with common media extensions
+    # ---------------------------------------------------------------------------
+    _filedir '@(mkv|mp4|mov|avi|webm|flv|wmv|m4v|ts|mts|m2ts|mpg|mpeg|ogv|3gp|rm|rmvb)'
+}
+
+complete -F _transcode_sh transcode.sh
+complete -F _transcode_sh transcode