detect ffmpeg binary + better logging

README.txt

@@ -1,4 +1,8 @@
-usage: video-randomizer [-h] [-o OUTPUT] [-d DURATION] [-s SAMPLE] [-p HEIGHT] [-w WIDTH] [-f FRAMERATE] [-i IGNORE] [--dry] [-q] [-qf] [--crf CRF] [-r SEED] file [file ...]
+usage: video-randomizer.py [-h] [-o OUTPUT] [-d DURATION] [-s SAMPLE]
+                           [-p HEIGHT] [-w WIDTH] [-f FRAMERATE] [-i IGNORE]
+                           [--dry] [-q] [-qf] [--crf CRF] [-r SEED]
+                           [--ffmpeg FFMPEG]
+                           file [file ...]
 
 randomize videos by taking small random samples and merging them together
 
@@ -10,7 +14,8 @@ optional arguments:
   -o OUTPUT, --output OUTPUT
                         output video path (default: random_[time].mp4)
   -d DURATION, --duration DURATION
-                        floating duration of output video in seconds (default: 60s)
+                        floating duration of output video in seconds (default:
+                        60s)
   -s SAMPLE, --sample SAMPLE
                         floating samples duration in seconds (default: 1s)
   -p HEIGHT, --height HEIGHT
@@ -20,9 +25,11 @@ optional arguments:
   -f FRAMERATE, --framerate FRAMERATE
                         output video framerate (default: 30fps)
   -i IGNORE, --ignore IGNORE
-                        video input content start/end ignore in % (default: 10)
+                        video input content start/end ignore in % (default:
+                        10)
   --dry                 dry mode, do not output video
   -q, --quiet           silent mode
-  -qf, --ffmpeg-quiet   do not output ffmpeg stdout
+  -qf, --quiet-ffmpeg   do not output ffmpeg stdout
   --crf CRF             libx264 Constant Rate Factor (default: 23)
-  -r SEED, --seed SEED  random seed
+  -r SEED, --seed SEED  random seed
+  --ffmpeg FFMPEG       ffmpeg binary path (default is found on PATH)