bitc.py - ffmpeg command fixed for logo option

[hyz2993]

Fixed:

• logo option requires -filter_complex option to replace -vf.

[vf#0:0 @ 0x600003549680] Simple filtergraph 'overlay=main_w-overlay_w-5:5' was expected to have exactly 1 input and 1 output. However, it had 2 input(s) and 1 output(s). Please adjust, or use a complex filtergraph (-filter_complex) instead.
[vost#0:0/libx264 @ 0x126e08510] Error initializing a simple filtergraph
Error opening output file /Volumes/......_h264.mov.
Error opening output files: Invalid argument

• ffmpeg cannot locate stream from multiple streams (video and timecode mostly) in the input for overlay.

[fc#0 @ 0x600001824000] Cannot find a matching stream for unlabeled input pad overlay
Error binding filtergraph inputs/outputs: Invalid argument

• Output is generated with two video streams: one with logo and one without. And the default stream was set to the latter.