videowmark: die on error

Signed-off-by: Stefan Westerfeld <stefan@space.twc.de>

src/TODO

@@ -2,6 +2,5 @@ possible improvements:
 - dynamic bit strength
 
 plausibility checks
-die on errors
 stream issue
 opus length ffprobe -show_format phil.mkv

src/videowmark

 #!/bin/bash
 
 
+function die
+{
+  echo >&2 "videowmark: error: $@"
+  exit 1
+}
+
 # auto detect codec and bitrate from input stream, generate ffmpeg options for audio encoder
 function audio_encode_options
 {
@@ -85,20 +91,21 @@ if [ "$1" == "add" ]; then
   wm_wav=/dev/fd/4
 
   # get audio as wav
-  ffmpeg $FFMPEG_VERBOSE -y -i "$2" -f wav "$orig_wav"
+  ffmpeg $FFMPEG_VERBOSE -y -i "$2" -f wav "$orig_wav" || die "extracting audio from video failed (ffmpeg)"
   # watermark
-  audiowmark "${AUDIOWMARK_ARGS[@]}" add "$orig_wav" "$wm_wav" "$4"
+  audiowmark "${AUDIOWMARK_ARGS[@]}" add "$orig_wav" "$wm_wav" "$4" || die "watermark generation failed (audiowmark)"
   # rejoin
-  ffmpeg $FFMPEG_VERBOSE -y -i "$2" -i "$wm_wav" -c:v copy $(audio_encode_options "$2") -map 0:v:0 -map 1:a:0 "$3"
+  ffmpeg $FFMPEG_VERBOSE -y -i "$2" -i "$wm_wav" -c:v copy $(audio_encode_options "$2") -map 0:v:0 -map 1:a:0 "$3" || \
+    die "merging video and watermarked audio failed (ffmpeg)"
 elif [ "$1" == "get" ]; then
   # create tmpfiles
   create_temp_files 3
   wav=/dev/fd/3
 
   # get audio as wav
-  ffmpeg $FFMPEG_VERBOSE -y -i "$2" -f wav "$wav"
+  ffmpeg $FFMPEG_VERBOSE -y -i "$2" -f wav "$wav" || die "extracting audio from video failed (ffmpeg)"
   # get watermark
-  audiowmark "${AUDIOWMARK_ARGS[@]}" get "$wav"
+  audiowmark "${AUDIOWMARK_ARGS[@]}" get "$wav" || die "retrieving watermark from audio failed (audiowmark)"
 elif [ "$1" == "probe" ]; then
   echo $2 $(audio_encode_options "$2")
 else