Linux ffmpeg output

to hide [swscaler @ 0xa899060] Warning , i can used "-vf format=rgb24" , but same frame drop remains.

linux output:

Data: ffmpeg version N-37504-gfeccf2f Copyright (c) 2000-2013 the FFmpeg developers
  built on Mar 13 2013 13:34:13 with gcc 4.6 (Ubuntu/Linaro 4.6.3-1ubuntu5)
  configuration: --enable-gpl --enable-libass --enable-libfdk-aac --enable-libmp3lame --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libspeex --enable-librtmp --enable-libtheora --enable-libvorbis --enable-libvpx --enable-x11grab --enable-libx264 --enable-nonfree --enable-version3

Data:   libavutil      52. 19.100 / 52. 19.100
  libavcodec     55.  0.100 / 55.  0.100
  libavformat    55.  0.100 / 55.  0.100
  libavdevice    54.  4.100 / 54.  4.100
  libavfilter     3. 45.101 /  3. 45.101
  libswscale      2.  2.100 /  2.  2.100
  libswresample   0. 17.102 /  0. 17.102
  libpostproc    52.  2.100 / 52.  2.100

Data: [rawvideo @ 0xa8aa660] Estimating duration from bitrate, this may be inaccurate
Input #0, rawvideo, from 'pipe:':
  Duration: N/A, start: 0.000000, bitrate: 196608 kb/s
    Stream #0:0: Video: rawvideo (ARGB / 0x42475241), argb, 640x320, 196608 kb/s, 30 tbr, 30 tbn, 30 tbc

Data: Output #0, flv, to 'demo2013.flv':
  Metadata:
    encoder         : Lavf55.0.100
    Stream #0:0: Video: flv1 ([2][0][0][0] / 0x0002), yuv420p, 640x320, q=2-31, 200 kb/s, 1k tbn, 30 tbc
Stream mapping:
  Stream #0:0 -> #0:0 (rawvideo -> flv)
[swscaler @ 0xa899060] Warning: data is not aligned! This can lead to a speedloss

Data: frame=    3 fps=0.0 q=10.0 size=      49kB time=00:00:00.10 bitrate=4043.4kbits/s
Data: frame=    4 fps=2.4 q=10.0 size=      65kB time=00:00:00.13 bitrate=4000.1kbits/s
Data: frame=    5 fps=1.9 q=10.0 size=      82kB time=00:00:00.16 bitrate=4045.3kbits/s
Data: frame=    6 fps=1.8 q=10.0 size=      99kB time=00:00:00.20 bitrate=4061.1kbits/s
Data: frame=    7 fps=1.7 q=10.0 size=     115kB time=00:00:00.23 bitrate=4051.1kbits/s
Data: frame=    8 fps=1.7 q=10.0 size=     132kB time=00:00:00.26 bitrate=4058.5kbits/s
Data: frame=    9 fps=1.6 q=10.0 size=     149kB time=00:00:00.30 bitrate=4056.8kbits/s
Data: frame=   10 fps=1.6 q=10.0 size=     165kB time=00:00:00.33 bitrate=4058.5kbits/s
Data: frame=   11 fps=1.6 q=10.0 size=     184kB time=00:00:00.36 bitrate=4109.0kbits/s