FFmpeg Thumbnail Extraction Error

$ ffmpeg -y -i input.ogv -vcodec mjpeg -ss $SEEK_POINT -vframes 1 -an -s 120x90 -f rawvideo output.jpg
Input #0, ogg, from 'input.ogv':
  Duration: 00:21:52.76, start: 0.000000, bitrate: 844 kb/s
    Stream #0.0: Video: theora, yuv420p, 800x600 [PAR 4:3 DAR 16:9], 25 fps, 25 tbr, 25 tbn, 25 tbc
    Stream #0.1: Audio: vorbis, 44100 Hz, stereo, s16, 192 kb/s
    Metadata:
      ENCODER         : Lavf52.102.0
Incompatible pixel format 'yuv420p' for codec 'mjpeg', auto-selecting format 'yuvj420p'
[buffer @ 0x9250840] w:800 h:600 pixfmt:yuv420p
[scale @ 0x92508a0] w:800 h:600 fmt:yuv420p -> w:120 h:90 fmt:yuvj420p flags:0x4
Output #0, rawvideo, to 'output.jpg':
  Metadata:
    encoder         : Lavf53.2.0
    Stream #0.0: Video: mjpeg, yuvj420p, 120x90 [PAR 4:3 DAR 16:9], q=2-31, 200 kb/s, 90k tbn, 25 tbc
Stream mapping:
  Stream #0.0 -> #0.0
Press ctrl-c to stop encoding
[buffer @ 0x9250840] Buffering several frames is not supported. Please consume all available frames before adding a new one.
frame=    0 fps=  0 q=0.0 size=       0kB time=10000000000.00 bitrate=   0.0kbit
frame=    0 fps=  0 q=0.0 size=       0kB time=10000000000.00 bitrate=   0.0kbit
frame=    0 fps=  0 q=0.0 size=       0kB time=10000000000.00 bitrate=   0.0kbit
frame=    0 fps=  0 q=0.0 size=       0kB time=10000000000.00 bitrate=   0.0kbit
frame=    0 fps=  0 q=0.0 size=       0kB time=10000000000.00 bitrate=   0.0kbit
Last message repeated 15448 times
frame=    1 fps=  0 q=3.4 Lsize=       3kB time=0.04 bitrate= 598.8kbits/s
video:3kB audio:0kB global headers:0kB muxing overhead 0.000000%