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• Problems video playing in some android devices (version 4+) but not in others

  5 juin 2014, par anquegi

  following the settings for video in android developers, http://developer.android.com/guide/appendix/media-formats.html I encoded a video using ffmpeg like this :

  ffmpeg -i gravityTrailer.mp4 -y -f mp4 -vcodec libx264 -profile:v baseline -acodec aac    -strict -2  -profile:a aac_low -b:v 500k -ar 44100 -b:a 128k -ac 2 -r 30 -s 480x360  output_hq.mp4

  which corresponds on sd highquality in table 2 from android developers (link above).

  Then i put this video in a server and use the class android.media.MediaPlayer to reproduce it from that URL like this

  https://cloudapp.somedomain.com/bmftvideos/output_hq.mp4

  The problem is that the video is played on android version 4+

  you can see the video on :
  LG G2,
  Sony xperia S

  you cannot see the video on :
  Samsung galaxy S4,
  BQ (spanish) aquaris 4.5

  And I don not know why

  this is the ffmpeg output :

  ffmpeg version 1.2.6 Copyright (c) 2000-2014 the FFmpeg developers
  
    built on Mar  5 2014 08:21:01 with gcc 4.8.2 (GCC) 20131212 (Red Hat 4.8.2-7)
  
    configuration: --prefix=/usr --bindir=/usr/bin --datadir=/usr/share/ffmpeg --incdir=/usr/include/ffmpeg --libdir=/usr/lib64 --mandir=/usr/share/man --arch=x86_64 --optflags='-O2 -g -pipe -Wall -Wp,-D_FORTIFY_SOURCE=2 -fexceptions -fstack-protector --param=ssp-buffer-size=4 -grecord-gcc-switches -m64 -mtune=generic' --enable-bzlib --disable-crystalhd --enable-frei0r --enable-gnutls --enable-libass --enable-libcelt --enable-libdc1394 --disable-indev=jack --enable-libfreetype --enable-libgsm --enable-libmp3lame --enable-openal --enable-libopencv --enable-libopenjpeg --enable-libopus --enable-libpulse --enable-libschroedinger --enable-libspeex --enable-libtheora --enable-libvorbis --enable-libv4l2 --enable-libvpx --enable-libx264 --enable-libxvid --enable-x11grab --enable-avfilter --enable-avresample --enable-postproc --enable-pthreads --disable-static --enable-shared --enable-gpl --disable-debug --disable-stripping --shlibdir=/usr/lib64 --enable-runtime-cpudetect
  
    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
  
  [mov,mp4,m4a,3gp,3g2,mj2 @ 0x14e5ba0] stream 0, timescale not set
  
  [mov,mp4,m4a,3gp,3g2,mj2 @ 0x14e5ba0] max_analyze_duration 5000000 reached at 5013333 microseconds
  
  Input #0, mov,mp4,m4a,3gp,3g2,mj2, from 'gravityTrailer.mp4':
  
    Metadata:
  
      major_brand     : mp42
  
      minor_version   : 0
  
      compatible_brands: mp42isomavc1
  
      creation_time   : 2013-12-01 03:59:56
  
      genre           : Trailer
  
      artist          : Warner Bros.
  
      title           : Gravity - 2K Trailer
  
      encoder         : HandBrake 0.9.9 2013051800
  
      date            : 2013
  
    Duration: 00:02:27.07, start: 0.000000, bitrate: 20296 kb/s
  
      Stream #0:0(und): Video: h264 (High) (avc1 / 0x31637661), yuv420p, 2048x858, 20149 kb/s, 23.98 fps, 23.98 tbr, 90k tbn, 47.95 tbc
  
      Metadata:
  
        creation_time   : 2013-12-01 03:59:56
  
      Stream #0:1(eng): Audio: aac (mp4a / 0x6134706D), 48000 Hz, stereo, fltp, 153 kb/s
  
      Metadata:
  
        creation_time   : 2013-12-01 03:59:56
  
      Stream #0:2: Video: mjpeg, yuvj420p, 102x150 [SAR 72:72 DAR 17:25], 90k tbr, 90k tbn, 90k tbc
  
  [libx264 @ 0x1667680] using cpu capabilities: MMX2 SSE2Fast SSSE3 SSE4.2 AVX
  
  [libx264 @ 0x1667680] profile Constrained Baseline, level 3.0
  
  [libx264 @ 0x1667680] 264 - core 130 r2282 1db4621 - H.264/MPEG-4 AVC codec - Copyleft 2003-2013 - http://www.videolan.org/x264.html - options: cabac=0 ref=3 deblock=1:0:0 analyse=0x1:0x111 me=hex subme=7 psy=1 psy_rd=1.00:0.00 mixed_ref=1 me_range=16 chroma_me=1 trellis=1 8x8dct=0 cqm=0 deadzone=21,11 fast_pskip=1 chroma_qp_offset=-2 threads=6 lookahead_threads=1 sliced_threads=0 nr=0 decimate=1 interlaced=0 bluray_compat=0 constrained_intra=0 bframes=0 weightp=0 keyint=250 keyint_min=25 scenecut=40 intra_refresh=0 rc_lookahead=40 rc=abr mbtree=1 bitrate=500 ratetol=1.0 qcomp=0.60 qpmin=0 qpmax=69 qpstep=4 ip_ratio=1.40 aq=1:1.00
  
  Output #0, mp4, to 'output_hq.mp4':
  
    Metadata:
  
      major_brand     : mp42
  
      minor_version   : 0
  
      compatible_brands: mp42isomavc1
  
      date            : 2013
  
      genre           : Trailer
  
      artist          : Warner Bros.
  
      title           : Gravity - 2K Trailer
  
      encoder         : Lavf54.63.104
  
      Stream #0:0(und): Video: h264 ([33][0][0][0] / 0x0021), yuv420p, 480x360, q=-1--1, 500 kb/s, 15360 tbn, 30 tbc
  
      Metadata:
  
        creation_time   : 2013-12-01 03:59:56
  
      Stream #0:1(eng): Audio: aac ([64][0][0][0] / 0x0040), 44100 Hz, stereo, fltp, 128 kb/s
  
      Metadata:
  
        creation_time   : 2013-12-01 03:59:56
  
  Stream mapping:
  
    Stream #0:0 -> #0:0 (h264 -> libx264)
  
    Stream #0:1 -> #0:1 (aac -> aac)
  
  Press [q] to stop, [?] for help
  
  frame= 4410 fps= 65 q=-1.0 Lsize=   11154kB time=00:02:27.07 bitrate= 621.3kbits/s dup=885 drop=0    
  
  video:9062kB audio:1969kB subtitle:0 global headers:0kB muxing overhead 1.115392%
  
  [libx264 @ 0x1667680] frame I:186   Avg QP:28.41  size:  4446
  
  [libx264 @ 0x1667680] frame P:4224  Avg QP:29.20  size:  2001
  
  [libx264 @ 0x1667680] mb I  I16..4: 75.5%  0.0% 24.5%
  
  [libx264 @ 0x1667680] mb P  I16..4:  7.5%  0.0%  3.6%  P16..4: 23.1%  6.2%  1.8%  0.0%  0.0%    skip:57.7%
  
  [libx264 @ 0x1667680] final ratefactor: 27.96
  
  [libx264 @ 0x1667680] coded y,uvDC,uvAC intra: 24.0% 31.9% 8.6% inter: 7.4% 7.6% 0.6%
  
  [libx264 @ 0x1667680] i16 v,h,dc,p: 58% 15% 13% 14%
  
  [libx264 @ 0x1667680] i4 v,h,dc,ddl,ddr,vr,hd,vl,hu: 28%  9% 27%  7%  6%  8%  5%  7%  3%
  
  [libx264 @ 0x1667680] i8c dc,h,v,p: 80%  7% 12%  2%
  
  [libx264 @ 0x1667680] ref P L0: 84.7%  9.4%  5.9%
  
  [libx264 @ 0x1667680] kb/s:504.98

  ---

• Church of JPEG

  25 mai 2014, par Mans — Random ramblings

  Some time has passed since I last wrote about the antics of the IJG, purveyor of the well-known JPEG image manipulation library. With the major Linux distributions as well as the Firefox and Chrome browsers having switched to the libjpeg-turbo fork, there has been little reason to pay attention to … Continue reading →

• Cortex-A7 instruction cycle timings

  15 mai 2014, par Mans — ARM

  The Cortex-A7 ARM core is a popular choice in low-power and low-cost designs. Unfortunately, the public TRM does not include instruction timing information. It does reveal that execution is in-order which makes measuring the throughput and latency for individual instructions relatively straight-forward. The table below lists the measured issue cycles … Continue reading →