[FFmpeg-user] I am unable to get ffmpeg to calculate PSNR for any video files.

[Gyan Doshi]

On 19-01-2021 10:38 pm, Reed Crowe wrote:
> Still does not work.
> With this command:
> ffmpeg -i /home/rcrowe/LVT/17647_20210118_195325.mp4 -i
> /home/rcrowe/LVT/test.mp4 -enc_time_base -1 -filter_complex psnr -f null -
> I get the same results:
> ffmpeg version N-100671-gc48110a4a4 Copyright (c) 2000-2021 the FFmpeg
> developers
>    built with gcc 7 (Ubuntu 7.5.0-3ubuntu1~18.04)
>    configuration:
>    libavutil      56. 63.101 / 56. 63.101
>    libavcodec     58.117.101 / 58.117.101
>    libavformat    58. 65.101 / 58. 65.101
>    libavdevice    58. 11.103 / 58. 11.103
>    libavfilter     7. 96.100 /  7. 96.100
>    libswscale      5.  8.100 /  5.  8.100
>    libswresample   3.  8.100 /  3.  8.100
> Input #0, mov,mp4,m4a,3gp,3g2,mj2, from
> '/home/rcrowe/LVT/17647_20210118_195325.mp4':
>    Metadata:
>      major_brand     : isom
>      minor_version   : 512
>      compatible_brands: isomiso2avc1mp41
>      title           : 'LVT17647'
>      encoder         : Lavf58.20.100
>    Duration: 00:00:59.87, start: 0.000000, bitrate: 67 kb/s
>      Stream #0:0(und): Video: h264 (Main) (avc1 / 0x31637661), yuvj420p(pc,
> bt470bg/bt470bg/bt709), 704x480, 66 kb/s, 15.03 fps, 15 tbr, 90k tbn, 180k
> tbc (default)
>      Metadata:
>        handler_name    : VideoHandler
>        vendor_id       : [0][0][0][0]
> Input #1, mov,mp4,m4a,3gp,3g2,mj2, from '/home/rcrowe/LVT/test.mp4':
>    Metadata:
>      major_brand     : isom
>      minor_version   : 512
>      compatible_brands: isomiso2avc1mp41
>      title           : 'LVT17647'
>      encoder         : Lavf58.20.100
>    Duration: 00:00:59.87, start: 0.000000, bitrate: 67 kb/s
>      Stream #1:0(und): Video: h264 (Main) (avc1 / 0x31637661), yuvj420p(pc,
> bt470bg/bt470bg/bt709), 704x480, 66 kb/s, 15.03 fps, 15 tbr, 90k tbn, 180k
> tbc (default)
>      Metadata:
>        handler_name    : VideoHandler
>        vendor_id       : [0][0][0][0]
> Stream mapping:
>    Stream #0:0 (h264) -> psnr:main
>    Stream #1:0 (h264) -> psnr:reference
>    psnr -> Stream #0:0 (wrapped_avframe)
> Press [q] to stop, [?] for help
> [null @ 0x559c3fc0d6c0] Input stream data not available, using default time
> base
> Output #0, null, to 'pipe:':
>    Metadata:
>      major_brand     : isom
>      minor_version   : 512
>      compatible_brands: isomiso2avc1mp41
>      title           : 'LVT17647'
>      encoder         : Lavf58.65.101
>      Stream #0:0: Video: wrapped_avframe, yuvj420p(pc,
> bt470bg/bt470bg/bt709, progressive), 704x480, q=2-31, 200 kb/s, 15 fps, 15
> tbn (default)
>      Metadata:
>        encoder         : Lavc58.117.101 wrapped_avframe
> *[null @ 0x559c3fc0d6c0] Application provided invalid, non monotonically
> increasing dts to muxer in stream 0: 748 >= 748*
> frame=  899 fps=0.0 q=-0.0 Lsize=N/A time=00:00:59.86 bitrate=N/A
> speed=79.3x
> video:471kB audio:0kB subtitle:0kB other streams:0kB global headers:0kB
> muxing overhead: unknown
> *[Parsed_psnr_0 @ 0x559c3fe87bc0] PSNR y:inf u:inf v:inf average:inf
> min:inf max:inf*

The results are right above, on the last line.  'inf' is infinity 
meaning the two inputs are identical.

Regards,
Gyan