Same Error after waiting a few minutes:
2017/12/28 15:20:32 [HWE] Trying /Users/parents/channels-dvr/latest/ffmpeg /Users/parents/channels-dvr/latest/ffmpeg -hide_banner -nostats -loglevel warning -loglevel verbose -f lavfi -t 0.1 -i color=black:640x480 -c:v h264_videotoolbox -profile:v high -level 4.2 -realtime 1 -f null -y /dev/null
[Parsed_color_0 @ 0x7fa08c4031e0] size:640x480 rate:25/1 duration:-1.000000 sar:1/1
Input #0, lavfi, from 'color=black:640x480':
Duration: N/A, start: 0.000000, bitrate: N/A
Stream #0:0: Video: rawvideo, 1 reference frame (I420 / 0x30323449), yuv420p, 640x480 [SAR 1:1 DAR 4:3], 25 tbr, 25 tbn, 25 tbc
Stream mapping:
Stream #0:0 -> #0:0 (rawvideo (native) -> h264 (h264_videotoolbox))
Press [q] to stop, [?] for help
[graph 0 input from stream 0:0 @ 0x7fa08c500680] w:640 h:480 pixfmt:yuv420p tb:1/25 fr:25/1 sar:1/1 sws_param:flags=2
[h264_videotoolbox @ 0x7fa08c830400] Error: cannot create compression session: -12915
[h264_videotoolbox @ 0x7fa08c830400] Try -allow_sw 1. The hardware encoder may be busy, or not supported.
Error initializing output stream 0:0 -- Error while opening encoder for output stream #0:0 - maybe incorrect parameters such as bit_rate, rate, width or height
Conversion failed!
GVA info: Successfully connected to the Intel plugin, offline Gen75
AVDCreateGPUAccelerator: Error loading GPU renderer
2017/12/28 15:20:33 [HWE] Failure: exit status 1
Looks like command worked after login in with a user:
2017/12/28 15:23:39 [HWE] Trying /Users/parents/channels-dvr/latest/ffmpeg /Users/parents/channels-dvr/latest/ffmpeg -hide_banner -nostats -loglevel warning -loglevel verbose -f lavfi -t 0.1 -i color=black:640x480 -c:v h264_videotoolbox -profile:v high -level 4.2 -realtime 1 -f null -y /dev/null
[Parsed_color_0 @ 0x7f978b600340] size:640x480 rate:25/1 duration:-1.000000 sar:1/1
Input #0, lavfi, from 'color=black:640x480':
Duration: N/A, start: 0.000000, bitrate: N/A
Stream #0:0: Video: rawvideo, 1 reference frame (I420 / 0x30323449), yuv420p, 640x480 [SAR 1:1 DAR 4:3], 25 tbr, 25 tbn, 25 tbc
Stream mapping:
Stream #0:0 -> #0:0 (rawvideo (native) -> h264 (h264_videotoolbox))
Press [q] to stop, [?] for help
[graph 0 input from stream 0:0 @ 0x7f978b603840] w:640 h:480 pixfmt:yuv420p tb:1/25 fr:25/1 sar:1/1 sws_param:flags=2
Output #0, null, to '/dev/null':
Metadata:
encoder : Lavf57.71.100
Stream #0:0: Video: h264 (h264_videotoolbox), 1 reference frame, yuv420p, 640x480 [SAR 1:1 DAR 4:3], q=2-31, 200 kb/s, 25 fps, 25 tbn, 25 tbc
Metadata:
encoder : Lavc57.89.100 h264_videotoolbox
[h264_videotoolbox @ 0x7f978c828a00] Color range not set for yuv420p. Using MPEG range.
No more output streams to write to, finishing.
frame= 3 fps=0.0 q=-0.0 Lsize=N/A time=00:00:00.12 bitrate=N/A speed=0.699x
video:0kB audio:0kB subtitle:0kB other streams:0kB global headers:0kB muxing overhead: unknown
Input file #0 (color=black:640x480):
Input stream #0:0 (video): 4 packets read (1843200 bytes); 4 frames decoded;
Total: 4 packets (1843200 bytes) demuxed
Output file #0 (/dev/null):
Output stream #0:0 (video): 3 frames encoded; 3 packets muxed (217 bytes);
Total: 3 packets (217 bytes) muxed
GVA info: Successfully connected to the Intel plugin, offline Gen75