指定FFmpeg命令将3GP转换为PNG失败的问题求助

大家好，我在使用FFmpeg把3GP视频转成PNG格式时碰到了问题，想请教下社区里的大佬有没有解决思路。

我用的命令是：

ffmpeg -skip_frame nokey -i input.3gp -vsync vfr -frame_pts true output.png

注：这个命令不能修改，它是来自谷歌测试用例的代码片段

执行命令后，我得到了如下报错信息：

ffmpeg version 4.2.7 Copyright (c) 2000-2022 the FFmpeg developers
  built with gcc 7 (Ubuntu 7.5.0-3ubuntu1~18.04)
  configuration:
  libavutil      56. 31.100 / 56. 31.100
  libavcodec     58. 54.100 / 58. 54.100
  libavformat    58. 29.100 / 58. 29.100
  libavdevice    58.  8.100 / 58.  8.100
  libavfilter     7. 57.100 /  7. 57.100
  libswscale      5.  5.100 /  5.  5.100
  libswresample   3.  5.100 /  3.  5.100
Input #0, mov,mp4,m4a,3gp,3g2,mj2, from 'VID_20240327_034002_0_LOW_176x144.3gp':
  Metadata:
    major_brand     : 3gp4
    minor_version   : 0
    compatible_brands: isom3gp4
    creation_time   : 2024-03-27T07:40:05.000000Z
    com.android.version: 13
  Duration: 00:00:02.95, start: 0.000000, bitrate: 144 kb/s
    Stream #0:0(eng): Video: h264 (High) (avc1 / 0x31637661), yuvj420p(pc, bt470bg/bt470bg/smpte170m), 176x144, 137 kb/s, 29.97 fps, 29.92 tbr, 90k tbn, 180k tbc (default)
    Metadata:
      creation_time   : 2024-03-27T07:40:05.000000Z
      handler_name    : VideoHandle
    Stream #0:1(eng): Audio: amr_nb (samr / 0x726D6173), 8000 Hz, mono, flt, 12 kb/s (default)
    Metadata:
      creation_time   : 2024-03-27T07:40:05.000000Z
      handler_name    : SoundHandle
Stream mapping:
  Stream #0:0 -> #0:0 (h264 (native) -> png (native))
Press [q] to stop, [?] for help
[swscaler @ 0x55ccaac84dc0] deprecated pixel format used, make sure you did set range correctly
Output #0, image2, to 'output.png':
  Metadata:
    major_brand     : 3gp4
    minor_version   : 0
    compatible_brands: isom3gp4
    com.android.version: 13
    encoder         : Lavf58.29.100
    Stream #0:0(eng): Video: png, rgb24, 176x144, q=2-31, 200 kb/s, 29.92 fps, 29.92 tbn, 29.92 tbc (default)
    Metadata:
      creation_time   : 2024-03-27T07:40:05.000000Z
      handler_name    : VideoHandle
      encoder         : Lavc58.54.100 png
[image2 @ 0x55ccaaa36c40] Cannot write filename by pts of the frames.av_interleaved_write_frame(): Invalid argument
frame=    3 fps=0.0 q=-0.0 Lsize=N/A time=00:00:00.33 bitrate=N/A speed=24.7x
video:17kB audio:0kB subtitle:0kB other streams:0kB global headers:0kB muxing overhead: unknown
Conversion failed!

我已经试过好几个不同版本的FFmpeg了，但都没法正常完成转换。想问问有没有人遇到过类似的问题，或者有什么可行的解决方案能修复这个问题？

提前感谢大家的帮助，谢谢！

备注：内容来源于stack exchange，提问作者Alex