$ ffmpeg -f image2 -i PICT0005.JPG -i PICT0006.JPG -framerate 25 -r 50 show.mp4
ffmpeg version 1.2 Copyright (c) 2000-2013 the FFmpeg developers
  built on Apr  1 2013 09:33:17 with gcc 4.7.2 (GCC)
  configuration: --prefix=/usr --disable-debug --disable-static --enable-avresample --enable-dxva2 --enable-fontconfig --enable-gpl --enable-libass --enable-libbluray --enable-libfreetype --enable-libgsm --enable-libmodplug --enable-libmp3lame --enable-libopencore_amrnb --enable-libopencore_amrwb --enable-libopenjpeg --enable-libopus --enable-libpulse --enable-librtmp --enable-libschroedinger --enable-libspeex --enable-libtheora --enable-libv4l2 --enable-libvorbis --enable-libvpx --enable-libx264 --enable-libxvid --enable-postproc --enable-runtime-cpudetect --enable-shared --enable-vdpau --enable-version3 --enable-x11grab
  libavutil      52. 18.100 / 52. 18.100
  libavcodec     54. 92.100 / 54. 92.100
  libavformat    54. 63.104 / 54. 63.104
  libavdevice    54.  3.103 / 54.  3.103
  libavfilter     3. 42.103 /  3. 42.103
  libswscale      2.  2.100 /  2.  2.100
  libswresample   0. 17.102 /  0. 17.102
  libpostproc    52.  2.100 / 52.  2.100
Input #0, image2, from 'PICT0005.JPG':
  Duration: 00:00:00.04, start: 0.000000, bitrate: N/A
    Stream #0:0: Video: mjpeg, yuvj422p, 2048x1536, 25 tbr, 25 tbn, 25 tbc
Input #1, image2, from 'PICT0006.JPG':
  Duration: 00:00:00.04, start: 0.000000, bitrate: N/A
    Stream #1:0: Video: mjpeg, yuvj422p, 2048x1536, 25 tbr, 25 tbn, 25 tbc
File 'show.mp4' already exists. Overwrite ? [y/N] y
using cpu capabilities: MMX2 SSE2Slow SlowCTZ
[libx264 @ 0x205cca0] profile High, level 5.1
[libx264 @ 0x205cca0] 264 - core 129 r2238 9c4ba4b - H.264/MPEG-4 AVC codec - Copyleft 2003-2012 - http://www.videolan.org/x264.html - options: cabac=1 ref=3 deblock=1:0:0 analyse=0x3:0x113 me=hex subme=7 psy=1 psy_rd=1.00:0.00 mixed_ref=1 me_range=16 chroma_me=1 trellis=1 8x8dct=1 cqm=0 deadzone=21,11 fast_pskip=1 chroma_qp_offset=-2 threads=3 lookahead_threads=1 sliced_threads=0 nr=0 decimate=1 interlaced=0 bluray_compat=0 constrained_intra=0 bframes=3 b_pyramid=2 b_adapt=1 b_bias=0 direct=1 weightb=1 open_gop=0 weightp=2 keyint=250 keyint_min=25 scenecut=40 intra_refresh=0 rc_lookahead=40 rc=crf mbtree=1 crf=23.0 qcomp=0.60 qpmin=0 qpmax=69 qpstep=4 ip_ratio=1.40 aq=1:1.00
Output #0, mp4, to 'show.mp4':
  Metadata:
    encoder         : Lavf54.63.104
    Stream #0:0: Video: h264 ([33][0][0][0] / 0x0021), yuvj420p, 2048x1536, q=-1--1, 12800 tbn, 50 tbc
Stream mapping:
  Stream #0:0 -> #0:0 (mjpeg -> libx264)
Press [q] to stop, [?] for help
frame=    1 fps=0.0 q=31.0 Lsize=      75kB time=00:00:00.02 bitrate=30558.0kbits/s
video:74kB audio:0kB subtitle:0 global headers:0kB muxing overhead 1.006161%
[libx264 @ 0x205cca0] frame I:1     Avg QP:29.67  size: 74905
[libx264 @ 0x205cca0] mb I  I16..4: 15.6% 80.4%  4.0%
[libx264 @ 0x205cca0] 8x8 transform intra:80.4%
[libx264 @ 0x205cca0] coded y,uvDC,uvAC intra: 61.6% 63.0% 5.8%
[libx264 @ 0x205cca0] i16 v,h,dc,p: 21% 34%  9% 35%
[libx264 @ 0x205cca0] i8 v,h,dc,ddl,ddr,vr,hd,vl,hu:  8% 26% 17%  8%  7%  4% 11%  4% 14%
[libx264 @ 0x205cca0] i4 v,h,dc,ddl,ddr,vr,hd,vl,hu:  8% 34% 12% 11%  8%  4%  8%  5% 11%
[libx264 @ 0x205cca0] i8c dc,h,v,p: 59% 27% 11%  3%
[libx264 @ 0x205cca0] kb/s:29962.00