title: ffmpeg saves only first frame
body: <p>I generated rotating pictures in Python and now I want to create an animation from it using ffmpeg. But the generated video includes only the first frame (viewed in VLC) and is way to small (half the size of one png) for all 36 pictures. What am I doing wrong? Thank you.</p>
  <p>command in shell: <code>ffmpeg -framerate 5 -i &quot;./mov/movie%03d.png&quot; -y &quot;movie.mp4&quot;</code></p>
  <p>Files in Folder <code>mov</code>:</p>
  <ul>
  <li><code>movie000.png</code></li>
  <li><code>movie010.png</code></li>
  <li>..</li>
  <li><code>movie350.png</code></li>
  </ul>
  <p><code>ffmpeg</code> version f<code>fmpeg-20170620-ae6f6d4-win64-static</code></p>
  <p>output</p>
  <pre><code>ffmpeg version N-86537-gae6f6d4 Copyright (c) 2000-2017 the FFmpeg developers
    built with gcc 7.1.0 (GCC)
    configuration: --enable-gpl --enable-version3 --enable-cuda --enable-cuvid --e
  nable-d3d11va --enable-dxva2 --enable-libmfx --enable-nvenc --enable-avisynth --
  enable-bzlib --enable-fontconfig --enable-frei0r --enable-gnutls --enable-iconv
  --enable-libass --enable-libbluray --enable-libbs2b --enable-libcaca --enable-li
  bfreetype --enable-libgme --enable-libgsm --enable-libilbc --enable-libmodplug -
  -enable-libmp3lame --enable-libopencore-amrnb --enable-libopencore-amrwb --enabl
  e-libopenh264 --enable-libopenjpeg --enable-libopus --enable-librtmp --enable-li
  bsnappy --enable-libsoxr --enable-libspeex --enable-libtheora --enable-libtwolam
  e --enable-libvidstab --enable-libvo-amrwbenc --enable-libvorbis --enable-libvpx
   --enable-libwavpack --enable-libwebp --enable-libx264 --enable-libx265 --enable
  -libxavs --enable-libxvid --enable-libzimg --enable-lzma --enable-zlib
    libavutil      55. 66.100 / 55. 66.100
    libavcodec     57. 99.100 / 57. 99.100
    libavformat    57. 73.100 / 57. 73.100
    libavdevice    57.  7.100 / 57.  7.100
    libavfilter     6. 94.100 /  6. 94.100
    libswscale      4.  7.101 /  4.  7.101
    libswresample   2.  8.100 /  2.  8.100
    libpostproc    54.  6.100 / 54.  6.100
  Input #0, image2, from './mov/movie%03d.png':
    Duration: 00:00:00.20, start: 0.000000, bitrate: N/A
      Stream #0:0: Video: png, rgba(pc), 1152x864 [SAR 2834:2834 DAR 4:3], 5 tbr,
  5 tbn, 5 tbc
  Stream mapping:
    Stream #0:0 -&gt; #0:0 (png (native) -&gt; h264 (libx264))
  Press [q] to stop, [?] for help
  No pixel format specified, yuv444p for H.264 encoding chosen.
  Use -pix_fmt yuv420p for compatibility with outdated media players.
  [libx264 @ 00000000003ec140] using SAR=1/1
  [libx264 @ 00000000003ec140] using cpu capabilities: MMX2 SSE2Fast SSSE3 SSE4.2
  AVX FMA3 BMI2 AVX2
  [libx264 @ 00000000003ec140] profile High 4:4:4 Predictive, level 3.2, 4:4:4 8-b
  it
  [libx264 @ 00000000003ec140] 264 - core 150 r2833 df79067 - H.264/MPEG-4 AVC cod
  ec - Copyleft 2003-2017 - http://www.videolan.org/x264.html - options: cabac=1 r
  ef=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_pski
  p=1 chroma_qp_offset=4 threads=6 lookahead_threads=1 sliced_threads=0 nr=0 decim
  ate=1 interlaced=0 bluray_compat=0 constrained_intra=0 bframes=3 b_pyramid=2 b_a
  dapt=1 b_bias=0 direct=1 weightb=1 open_gop=0 weightp=2 keyint=250 keyint_min=5
  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 'movie.mp4':
    Metadata:
      encoder         : Lavf57.73.100
      Stream #0:0: Video: h264 (libx264) ([33][0][0][0] / 0x0021), yuv444p, 1152x8
  64 [SAR 1:1 DAR 4:3], q=-1--1, 5 fps, 10240 tbn, 5 tbc
      Metadata:
        encoder         : Lavc57.99.100 libx264
      Side data:
        cpb: bitrate max/min/avg: 0/0/0 buffer size: 0 vbv_delay: -1
  frame=    1 fps=0.0 q=23.0 Lsize=      19kB time=00:00:00.00 bitrate=1581142.9kb
  its/s speed=0.00138x
  video:18kB audio:0kB subtitle:0kB other streams:0kB global headers:0kB muxing ov
  erhead: 4.403838%
  [libx264 @ 00000000003ec140] frame I:1     Avg QP:17.26  size: 17865
  [libx264 @ 00000000003ec140] mb I  I16..4: 29.6% 56.0% 14.5%
  [libx264 @ 00000000003ec140] 8x8 transform intra:56.0%
  [libx264 @ 00000000003ec140] coded y,u,v intra: 11.5% 2.3% 6.3%
  [libx264 @ 00000000003ec140] i16 v,h,dc,p: 77% 22%  1%  0%
  [libx264 @ 00000000003ec140] i8 v,h,dc,ddl,ddr,vr,hd,vl,hu: 33%  3% 62%  0%  0%
   0%  0%  0%  0%
  [libx264 @ 00000000003ec140] i4 v,h,dc,ddl,ddr,vr,hd,vl,hu: 53% 25% 12%  1%  1%
   2%  1%  2%  1%
  [libx264 @ 00000000003ec140] kb/s:714.60
  </code></pre>