[FFmpeg-user] Errors in swscaler or broken video

[WR]

Hello community,

since some days I experience errormessages in ffplay:
(ffplay version 4.2.4-1ubuntu0.1 )

[swscaler @ 0x55c6a680c880] 82x0 -> 82x0 is invalid scaling dimension
Cannot initialize the conversion context
[swscaler @ 0x55c6a680c880] 82x0 -> 82x0 is invalid scaling dimension
Cannot initialize the conversion context
[swscaler @ 0x55c6a680c880] 82x0 -> 82x0 is invalid scaling dimension
Cannot initialize the conversion context
[swscaler @ 0x55c6a680c880] 82x0 -> 82x0 is invalid scaling dimension
Cannot initialize the conversion context
[swscaler @ 0x55c6a680c880] 82x0 -> 82x0 is invalid scaling dimension
Cannot initialize the conversion context
[swscaler @ 0x55c6a680c880] 82x0 -> 82x0 is invalid scaling dimension
Cannot initialize the conversion context
[swscaler @ 0x55c6a680c880] 291x0 -> 291x0 is invalid scaling dimension
Cannot initialize the conversion context
[swscaler @ 0x55c6a680c880] 291x0 -> 291x0 is invalid scaling dimension
Cannot initialize the conversion context
[swscaler @ 0x55c6a680c880] 291x0 -> 291x0 is invalid scaling dimension
Cannot initialize the conversion context
[swscaler @ 0x55c6a680c880] 291x0 -> 291x0 is invalid scaling dimension
Cannot initialize the conversion context
[swscaler @ 0x55c6a680c880] 291x0 -> 291x0 is invalid scaling dimension
Cannot initialize the conversion context
[swscaler @ 0x55c6a680c880] 291x0 -> 291x0 is invalid scaling dimension
Cannot initialize the conversion context
[swscaler @ 0x55c6a680c880] 291x0 -> 291x0 is invalid scaling dimension
Cannot initialize the conversion context
[swscaler @ 0x55c6a680c880] 291x0 -> 291x0 is invalid scaling dimension
Cannot initialize the conversion context

The messages arise in chunks and while they arise video output is black. 
between the chunks, the video runs fine.

It only happens, when I play a video, which I edited before with 
ffmpeg's crop-filter :
-c:v libx264 -preset medium  -filter:v crop=iw-0-0:ih-72-74:0:72

The source video comes from a DVD (from what I created a concat-file 
with dvd2concat-script from ffmpeg-sources)

I do that to cut the black stripes on the top and at the bottom.
When I don't use the crop filter, the result video runs fine in ffplay.

The cropped video (which produces the error messages) runs fine in other 
players (vlc, parole). I also (for test) took it as input for another 
transcoding in ffmpeg -> no errors while processing (but again errors 
while playing this result)

So my question is: can I be sure, that the cropped videofile is without 
scaling faults and only the ffplay has a problem while playing? Or is 
the cropped video really erroneous because the crop filter makes 
mistakes and all other players are a bit more "scaling problems friendly".

I think this appeared since one of the last ubuntu updates, I can't 
remember such an effect in former times, but I use the crop filter since 
a long time now.

(And another strange effect in the last days is, that video playback 
runs in double speed for some seconds, when I switch the audio-channels 
with key A. I've never seen this before.)

Thank you, RockfordC64

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May the source be with you