Error cropping picture for png images

[MKa2]

Hi everyone,
I would like to make a movie from some png images and crop the top.
The pngs have the size 3083x981.

ffmpeg -i img%d.png -croptop 10 finalVideo.mp4
yields the error

Input #0, image2, from 'img%d.png':
  Duration: 00:00:00.2, start: 0.000000, bitrate: N/A
  Stream #0.0: Video: png, rgb24, 3083x981, 25.00 fps(r)
Output #0, mp4, to 'finalVideo.mp4':
  Stream #0.0: Video: mpeg4, yuv420p, 3083x971, q=2-31, 200 kb/s, 25.00 fps(c)
Stream mapping:
  Stream #0.0 -> #0.0
Press [q] to stop encoding
error cropping picture
error cropping picture
error cropping picture
frame=    0 q=0.0 Lsize=       0kB time=10000000000.0 bitrate=   0.0kbits/s    
video:0kB audio:0kB global headers:0kB muxing overhead 233.333333%

With jpgs it works fine:
ffmpeg -i img%d.jpg finalVideo.mp4

Is the crop function generally not working for png images?

[poisondeathray]

But did you crop the .jpg as well for that jpg test?

It might be that crop values usually have to be even (and the image dimensions usually have to be even in video). So you could try resizing first to an even dimension size (e.g. 3082x970), then crop

[MKa2]

Hi, thanks for your reply.
I'm sorry, I meant
ffmpeg -i img%d.jpg -croptop 10 finalVideo.mp4
worked fine.

I thought the same thing as you. I tried it but still: For jpg no problem and for png there's an error.