Recherche avancée

Sur d’autres sites (11426)

• Statically built FFMPEG binary segmentation fault

  12 février 2020, par stevendesu

  I want to create a custom build of FFMPEG which rips out everything except for the ability to transmux HLS videos to MP4, and I need this build to be 100% static with no external dependencies

  I tried using the following configuration :

  ./configure \
  
      --extra-cflags='-static -static-libstdc++ -static-libgcc' \
  
      --extra-cxxflags='-static -static-libstdc++ -static-libgcc' \
  
      --extra-ldflags='-static -static-libstdc++ -static-libgcc' \
  
      --pkg-config-flags='--static' \
  
      --enable-static \
  
      --disable-shared \
  
      --disable-runtime-cpudetect \
  
      --disable-autodetect \
  
      --disable-ffplay \
  
      --disable-ffprobe \
  
      --disable-doc \
  
      --disable-avdevice \
  
      --disable-swresample \
  
      --disable-swscale \
  
      --disable-postproc \
  
      --disable-pthreads \
  
      --disable-w32threads \
  
      --disable-os2threads \
  
      --enable-network \
  
      --disable-dct \
  
      --disable-dwt \
  
      --disable-error-resilience \
  
      --disable-lsp \
  
      --disable-lzo \
  
      --disable-mdct \
  
      --disable-rdft \
  
      --disable-fft \
  
      --disable-faan \
  
      --disable-pixelutils \
  
      --disable-encoders \
  
      --disable-decoders \
  
      --disable-hwaccels \
  
      --disable-muxers \
  
      --enable-muxer=mov \
  
      --enable-muxer=mp4 \
  
      --disable-demuxers \
  
      --enable-demuxer=hls \
  
      --enable-demuxer=mpegts \
  
      --enable-demuxer=h264 \
  
      --enable-demuxer=aac \
  
      --disable-parsers \
  
      --enable-parser=h264 \
  
      --enable-parser=aac \
  
      --disable-bsfs \
  
      --disable-protocols \
  
      --enable-protocol=tcp \
  
      --enable-protocol=tls \
  
      --enable-protocol=http \
  
      --enable-protocol=https \
  
      --enable-protocol=hls \
  
      --disable-indevs \
  
      --disable-outdevs \
  
      --disable-devices \
  
      --disable-filters \
  
      --disable-alsa \
  
      --disable-appkit \
  
      --disable-avfoundation \
  
      --disable-bzlib \
  
      --disable-coreimage \
  
      --disable-iconv \
  
      --disable-lzma \
  
      --enable-openssl \
  
      --disable-sndio \
  
      --disable-sdl2 \
  
      --disable-securetransport \
  
      --disable-xlib \
  
      --disable-zlib \
  
      --disable-amf \
  
      --disable-audiotoolbox \
  
      --disable-cuda-llvm \
  
      --disable-cuvid \
  
      --disable-d3d11va \
  
      --disable-dxva2 \
  
      --disable-ffnvcodec \
  
      --disable-nvdec \
  
      --disable-nvenc \
  
      --disable-v4l2-m2m \
  
      --disable-vaapi \
  
      --disable-vdpau \
  
      --disable-videotoolbox \
  
      --disable-debug

  This looked about like what I wanted :

  install prefix            /usr/local
  
  source path               .
  
  C compiler                gcc
  
  C library                 glibc
  
  ARCH                      x86 (generic)
  
  big-endian                no
  
  runtime cpu detection     no
  
  standalone assembly       yes
  
  x86 assembler             nasm
  
  MMX enabled               yes
  
  MMXEXT enabled            yes
  
  3DNow! enabled            yes
  
  3DNow! extended enabled   yes
  
  SSE enabled               yes
  
  SSSE3 enabled             yes
  
  AESNI enabled             yes
  
  AVX enabled               yes
  
  AVX2 enabled              yes
  
  AVX-512 enabled           yes
  
  XOP enabled               yes
  
  FMA3 enabled              yes
  
  FMA4 enabled              yes
  
  i686 features enabled     yes
  
  CMOV is fast              yes
  
  EBX available             yes
  
  EBP available             yes
  
  debug symbols             no
  
  strip symbols             yes
  
  optimize for size         no
  
  optimizations             yes
  
  static                    yes
  
  shared                    no
  
  postprocessing support    no
  
  network support           yes
  
  threading support         no
  
  safe bitstream reader     yes
  
  texi2html enabled         no
  
  perl enabled              yes
  
  pod2man enabled           yes
  
  makeinfo enabled          no
  
  makeinfo supports HTML    no
  
  
  
  External libraries:
  
  openssl
  
  
  
  External libraries providing hardware acceleration:
  
  
  
  Libraries:
  
  avcodec                 avfilter                avformat                avutil
  
  
  
  Programs:
  
  ffmpeg
  
  
  
  Enabled decoders:
  
  
  
  Enabled encoders:
  
  
  
  Enabled hwaccels:
  
  
  
  Enabled parsers:
  
  aac                     h264
  
  
  
  Enabled demuxers:
  
  aac                     h264                    hls                     mpegts
  
  
  
  Enabled muxers:
  
  mov                     mp4
  
  
  
  Enabled protocols:
  
  hls                     http                    https                   tcp                     tls
  
  
  
  Enabled filters:
  
  aformat                 anull                   atrim                   format                  hflip                   null                    transpose               trim                    vflip
  
  
  
  Enabled bsfs:
  
  null
  
  
  
  Enabled indevs:
  
  
  
  Enabled outdevs:
  
  
  
  License: LGPL version 2.1 or later

  It included several filters which I won’t ever need or use, but these filters are pulled in automatically if you don’t specify --disable-avfilter, and specifying --disable-avfilter prevents the ffmpeg binary from being produced. So I’m stuck with those.

  Using these parameters and then running make, I received a binary that was about 5.9 MB in size and looked right :

  $> ldd ffmpeg
  
          not a dynamic executable

  But when I try to run it :

  $> ./ffmpeg -version
  
  Segmentation fault

  Using valgrind to try and inspect the cause of the segmentation fault :

  $> valgrind ./ffmpeg -version
  
  .... lots of stuff ...
  
  ==61362== Jump to the invalid address stated on the next line
  
  ==61362==    at 0x0: ???
  
  ==61362==    by 0x70BB1B: ??? (in /src/FFmpeg/ffmpeg)
  
  ==61362==    by 0x70B2E6: ??? (in /src/FFmpeg/ffmpeg)
  
  ==61362==    by 0x4033F9: ??? (in /src/FFmpeg/ffmpeg)
  
  ==61362==    by 0x1FFF000677: ???
  
  ==61362==  Address 0x0 is not stack'd, malloc'd or (recently) free'd
  
  ==61362==
  
  ==61362==
  
  ==61362== Process terminating with default action of signal 11 (SIGSEGV)
  
  ==61362==  Bad permissions for mapped region at address 0x0
  
  ==61362==    at 0x0: ???
  
  ==61362==    by 0x70BB1B: ??? (in /src/FFmpeg/ffmpeg)
  
  ==61362==    by 0x70B2E6: ??? (in /src/FFmpeg/ffmpeg)
  
  ==61362==    by 0x4033F9: ??? (in /src/FFmpeg/ffmpeg)
  
  ==61362==    by 0x1FFF000677: ???
  
  ==61362==
  
  ==61362== HEAP SUMMARY:
  
  ==61362==     in use at exit: 0 bytes in 0 blocks
  
  ==61362==   total heap usage: 0 allocs, 0 frees, 0 bytes allocated
  
  ==61362==
  
  ==61362== All heap blocks were freed -- no leaks are possible
  
  ==61362==
  
  ==61362== For counts of detected and suppressed errors, rerun with: -v
  
  ==61362== Use --track-origins=yes to see where uninitialised values come from
  
  ==61362== ERROR SUMMARY: 93 errors from 90 contexts (suppressed: 0 from 0)
  
  Segmentation fault

  Attempting to access memory at location 0x0 sounds like trying to follow a null pointer. But I’m not sure how to fix this.

  gdb backtrace

  When I first ran gdb ./ffmpeg gdb immediately gave me a segmentation fault and I wasn’t kicked into the gdb REPL, so I couldn’t investigate

  After rebuilding ffmpeg I was able to get in this time :

  $> gdb ./ffmpeg
  
  
  
  GNU gdb (Ubuntu 8.1-0ubuntu3.2) 8.1.0.20180409-git
  
  Copyright (C) 2018 Free Software Foundation, Inc.
  
  License GPLv3+: GNU GPL version 3 or later /gnu.org/licenses/gpl.html>
  
  This is free software: you are free to change and redistribute it.
  
  There is NO WARRANTY, to the extent permitted by law.  Type "show copying"
  
  and "show warranty" for details.
  
  This GDB was configured as "x86_64-linux-gnu".
  
  Type "show configuration" for configuration details.
  
  For bug reporting instructions, please see:
  
  /www.gnu.org/software/gdb/bugs/>.
  
  Find the GDB manual and other documentation resources online at:
  
  /www.gnu.org/software/gdb/documentation/>.
  
  For help, type "help".
  
  Type "apropos word" to search for commands related to "word"...
  
  Reading symbols from ffmpeg...done.
  
  (gdb) r
  
  Starting program: /src/FFmpeg/ffmpeg
  
  warning: Error disabling address space randomization: Operation not permitted
  
  
  
  Program received signal SIGSEGV, Segmentation fault.
  
  0x0000000000000000 in ?? ()
  
  (gdb) bt
  
  #0  0x0000000000000000 in ?? ()
  
  #1  0x0000000000f9a8d5 in __register_frame_info_bases.part.6 ()
  
  #2  0x00000000004445fd in frame_dummy ()
  
  #3  0x0000000000000001 in ?? ()
  
  #4  0x0000000000ebd20c in __libc_csu_init ()
  
  #5  0x0000000000ebc9d7 in __libc_start_main ()
  
  #6  0x000000000044451a in _start ()
  
  (gdb)

  I tried grep’ing the code base for __register_frame_info_bases and found nothing. So I’m not really sure where to go from here

  A fix, but not an explanation

  By randomly removing configuration parameters and rebuilding I discovered that --disable-pthreads was causing the segmentation fault. When I remove this, ffmpeg runs just fine

  I don’t know why this is the case, though. Why would they make it possible to remove something that you need to run ?

• FFmpeg seeking (-ss) not working on some devices

  4 juin 2020, par ClassA

  As the title states, -ss command is not working on some devices, like the Huawei Mate 10.

  



  Here is the command I'm using and how I get the values :

  



  Format formatter = new SimpleDateFormat("00:" + "mm:ss.SS");
// Video duration
long duration = getDuration();
// Video duration devided by 6 (I want to get 5 images)
long img1 = duration / 6;
String firstThumbTime = formatter.format(img1);
// Screen dimentions devided by 7
String dimentions = width + ":" + height;

String[] a = {"-ss", firstThumbTime, "-i", mStringFilePath, "-vframes", "1", "-s", dimentions, imageThumbsDirectory + "/" + "thumb1.bmp"};


  



  The command above looks like this :

  



  -ss 00:00:00.47 -i /storage/emulated/0/Android/data/com.my.package/files/MyVideos/2020_02_19_16_00_20.mp4 -vframes 1 -s 154:274 /storage/emulated/0/Android/data/com.my.package/files/ThumbTemp/thumb1.bmp


  



  The strange thing is that it completes without an error, but the output file is unreadable.

  



  I do not have the logs currently, but I have a user that can send it to me if you need it.

  



  ---

  



  I'm 100% sure that it is caused by -ss because I use a similar command for trimming a video elsewhere in my application and when the user exports the video without setting trimming points(-ss), then the video works.

  



  Here is the 2 command I use for trimming a video :

  



  Working :

  



  String[] s = {"-i", videonInputPath, "-crf", "18", "-c:v", "libx264", "-preset", "ultrafast", videoOutputPath};


  



  Not working

  



  String[] s = {"-ss", startValue, "-i", videonInputPath, "-crf", "18", "-c:v", "libx264", "-preset", "ultrafast", videoOutputPath};


  



  ---

  



  This is the first time a user sends me this issue, so it has to be something with his device.

  



  Any advice would greatly be appreciated.

  



  ---

  



  EDIT :

  



  Log as requested by @Gyan in the comment section below (Added -v 48 to command) :

  



  ffmpeg version n4.0-39-gda39990 Copyright (c) 2000-2018 the FFmpeg developers
built with gcc 4.9.x (GCC) 20150123 (prerelease)
configuration: --target-os=linux --cross-prefix=/root/bravobit/ffmpeg-android/toolchain-android/bin/arm-linux-androideabi- --arch=arm --cpu=cortex-a8 --enable-runtime-cpudetect --sysroot=/root/bravobit/ffmpeg-android/toolchain-android/sysroot --enable-pic --enable-libx264 --enable-ffprobe --enable-libopus --enable-libvorbis --enable-libfdk-aac --enable-libfreetype --enable-libfribidi --enable-libmp3lame --enable-fontconfig --enable-libvpx --enable-libass --enable-yasm --enable-pthreads --disable-debug --enable-version3 --enable-hardcoded-tables --disable-ffplay --disable-linux-perf --disable-doc --disable-shared --enable-static --enable-runtime-cpudetect --enable-nonfree --enable-network --enable-avresample --enable-avformat --enable-avcodec --enable-indev=lavfi --enable-hwaccels --enable-ffmpeg --enable-zlib --enable-gpl --enable-small --enable-nonfree --pkg-config=pkg-config --pkg-config-flags=--static --prefix=/root/bravobit/ffmpeg-android/build/armeabi-v7a --extra-cflags='-I/root/bravobit/ffmpeg-android/toolchain-android/include -U_FORTIFY_SOURCE -D_FORTIFY_SOURCE=2 -fno-strict-overflow -fstack-protector-all' --extra-ldflags='-L/root/bravobit/ffmpeg-android/toolchain-android/lib -Wl,-z,relro -Wl,-z,now -pie' --extra-cxxflags=
libavutil 56. 14.100 / 56. 14.100
libavcodec 58. 18.100 / 58. 18.100
libavformat 58. 12.100 / 58. 12.100
libavdevice 58. 3.100 / 58. 3.100
libavfilter 7. 16.100 / 7. 16.100
libavresample 4. 0. 0 / 4. 0. 0
libswscale 5. 1.100 / 5. 1.100
libswresample 3. 1.100 / 3. 1.100
libpostproc 55. 1.100 / 55. 1.100
Splitting the commandline.
Reading option '-ss' ... matched as option 'ss' (set the start time offset) with argument '00:30:02.58'.
Reading option '-i' ... matched as input url with argument '/storage/emulated/0/Download/email/VID-20180720-WA0001.mp4'.
Reading option '-v' ... matched as option 'v' (set logging level) with argument '48'.
Reading option '-vframes' ... matched as option 'vframes' (set the number of video frames to output) with argument '1'.
Reading option '-s' ... matched as option 's' (set frame size (WxH or abbreviation)) with argument '154:308'.
Reading option '/storage/emulated/0/Android/data/com.my.package/files/ThumbTemp/thumb1.bmp' ... matched as output url.
Finished splitting the commandline.
Parsing a group of options: global .
Applying option v (set logging level) with argument 48.
Successfully parsed a group of options.
Parsing a group of options: input url /storage/emulated/0/Download/email/VID-20180720-WA0001.mp4.
Applying option ss (set the start time offset) with argument 00:30:02.58.
Successfully parsed a group of options.
Opening an input file: /storage/emulated/0/Download/email/VID-20180720-WA0001.mp4.
[NULL @ 0xf1fa5000] Opening '/storage/emulated/0/Download/email/VID-20180720-WA0001.mp4' for reading
[file @ 0xf1f94000] Setting default whitelist 'file,crypto'
[mov,mp4,m4a,3gp,3g2,mj2 @ 0xf1fa5000] Format mov,mp4,m4a,3gp,3g2,mj2 probed with size=2048 and score=100
[mov,mp4,m4a,3gp,3g2,mj2 @ 0xf1fa5000] ISO: File Type Major Brand: mp42
[mov,mp4,m4a,3gp,3g2,mj2 @ 0xf1fa5000] Unknown dref type 0x206c7275 size 12
Last message repeated 1 times
[mov,mp4,m4a,3gp,3g2,mj2 @ 0xf1fa5000] rfps: 29.833333 0.018442
[mov,mp4,m4a,3gp,3g2,mj2 @ 0xf1fa5000] rfps: 29.916667 0.003419
Last message repeated 1 times
[mov,mp4,m4a,3gp,3g2,mj2 @ 0xf1fa5000] rfps: 30.000000 0.000764
Last message repeated 1 times
[mov,mp4,m4a,3gp,3g2,mj2 @ 0xf1fa5000] rfps: 60.000000 0.003057
Last message repeated 1 times
[mov,mp4,m4a,3gp,3g2,mj2 @ 0xf1fa5000] rfps: 120.000000 0.012228
[mov,mp4,m4a,3gp,3g2,mj2 @ 0xf1fa5000] rfps: 29.970030 0.000295
Last message repeated 1 times
[mov,mp4,m4a,3gp,3g2,mj2 @ 0xf1fa5000] rfps: 59.940060 0.001178
Last message repeated 1 times
[mov,mp4,m4a,3gp,3g2,mj2 @ 0xf1fa5000] Before avformat_find_stream_info() pos: 6937 bytes read:32768 seeks:0 nb_streams:2
[h264 @ 0xf1fda380] nal_unit_type: 7, nal_ref_idc: 1
[h264 @ 0xf1fda380] nal_unit_type: 8, nal_ref_idc: 1
[h264 @ 0xf1fda380] nal_unit_type: 6, nal_ref_idc: 0
[h264 @ 0xf1fda380] nal_unit_type: 5, nal_ref_idc: 1
[h264 @ 0xf1fda380] Format yuv420p chosen by get_format().
[h264 @ 0xf1fda380] Reinit context to 848x480, pix_fmt: yuv420p
[mov,mp4,m4a,3gp,3g2,mj2 @ 0xf1fa5000] All info found
[mov,mp4,m4a,3gp,3g2,mj2 @ 0xf1fa5000] After avformat_find_stream_info() pos: 67446 bytes read:67446 seeks:0 frames:45
Input #0, mov,mp4,m4a,3gp,3g2,mj2, from '/storage/emulated/0/Download/email/VID-20180720-WA0001.mp4':
Metadata:
major_brand : mp42
minor_version : 1
compatible_brands: mp41mp42isom
creation_time : 2018-07-20T19:57:44.000000Z
Duration: 00:00:15.52, start: 0.000000, bitrate: 1679 kb/s
Stream #0:0(und), 1, 1/600: Video: h264, 1 reference frame (avc1 / 0x31637661), yuv420p(tv, bt709, left), 848x480, 0/1, 1622 kb/s, 30.02 fps, 29.97 tbr, 600 tbn, 1200 tbc (default)
Metadata:
rotate : 90
creation_time : 2018-07-20T19:57:44.000000Z
handler_name : Core Media Video
Side data:
displaymatrix: rotation of -90.00 degrees
Stream #0:1(und), 44, 1/44100: Audio: aac (mp4a / 0x6134706D), 44100 Hz, stereo, fltp, 53 kb/s (default)
Metadata:
creation_time : 2018-07-20T19:57:44.000000Z
handler_name : Core Media Audio
Successfully opened the file.
Parsing a group of options: output url /storage/emulated/0/Android/data/com.my.package/files/ThumbTemp/thumb1.bmp.
Applying option vframes (set the number of video frames to output) with argument 1.
Applying option s (set frame size (WxH or abbreviation)) with argument 154:308.
Successfully parsed a group of options.
Opening an output file: /storage/emulated/0/Android/data/com.my.package/files/ThumbTemp/thumb1.bmp.
Successfully opened the file.
detected 8 logical cores
[h264 @ 0xf1fdbf80] nal_unit_type: 7, nal_ref_idc: 1
[h264 @ 0xf1fdbf80] nal_unit_type: 8, nal_ref_idc: 1
Stream mapping:
Stream #0:0 -> #0:0 (h264 (native) -> bmp (native))
Press [q] to stop, [?] for help
cur_dts is invalid (this is harmless if it occurs once at the start per stream)
Last message repeated 1 times
[h264 @ 0xf1fdbf80] nal_unit_type: 5, nal_ref_idc: 1
[h264 @ 0xf1fdbf80] Format yuv420p chosen by get_format().
[h264 @ 0xf1fdbf80] Reinit context to 848x480, pix_fmt: yuv420p
cur_dts is invalid (this is harmless if it occurs once at the start per stream)
[h264 @ 0xf1fdc300] nal_unit_type: 1, nal_ref_idc: 1
[h264 @ 0xf1fdc680] nal_unit_type: 1, nal_ref_idc: 1
cur_dts is invalid (this is harmless if it occurs once at the start per stream)
Last message repeated 1 times
[h264 @ 0xf1fdca00] nal_unit_type: 1, nal_ref_idc: 1
cur_dts is invalid (this is harmless if it occurs once at the start per stream)
[h264 @ 0xf1fdcd80] nal_unit_type: 1, nal_ref_idc: 1
cur_dts is invalid (this is harmless if it occurs once at the start per stream)
[h264 @ 0xf1fdd100] nal_unit_type: 1, nal_ref_idc: 1
cur_dts is invalid (this is harmless if it occurs once at the start per stream)
[h264 @ 0xf1fdd480] nal_unit_type: 1, nal_ref_idc: 1
cur_dts is invalid (this is harmless if it occurs once at the start per stream)
[h264 @ 0xf1fdd800] nal_unit_type: 1, nal_ref_idc: 1
[h264 @ 0xf1fddb80] nal_unit_type: 1, nal_ref_idc: 1
[graph 0 input from stream 0:0 @ 0xf1fe9360] Setting 'video_size' to value '848x480'
[graph 0 input from stream 0:0 @ 0xf1fe9360] Setting 'pix_fmt' to value '0'
[graph 0 input from stream 0:0 @ 0xf1fe9360] Setting 'time_base' to value '1/600'
[graph 0 input from stream 0:0 @ 0xf1fe9360] Setting 'pixel_aspect' to value '0/1'
[graph 0 input from stream 0:0 @ 0xf1fe9360] Setting 'sws_param' to value 'flags=2'
[graph 0 input from stream 0:0 @ 0xf1fe9360] Setting 'frame_rate' to value '30000/1001'
[graph 0 input from stream 0:0 @ 0xf1fe9360] w:848 h:480 pixfmt:yuv420p tb:1/600 fr:30000/1001 sar:0/1 sws_param:flags=2
[transpose @ 0xf1fe9420] Setting 'dir' to value 'clock'
[scaler_out_0_0 @ 0xf1fe9540] Setting 'w' to value '154'
[scaler_out_0_0 @ 0xf1fe9540] Setting 'h' to value '308'
[scaler_out_0_0 @ 0xf1fe9540] Setting 'flags' to value 'bicubic'
[scaler_out_0_0 @ 0xf1fe9540] w:154 h:308 flags:'bicubic' interl:0
[format @ 0xf1fe95a0] Setting 'pix_fmts' to value 'bgra|bgr24|rgb565le|rgb555le|rgb444le|rgb8|bgr8|rgb4_byte|bgr4_byte|gray|pal8|monob'
[AVFilterGraph @ 0xf1fb20c0] query_formats: 7 queried, 6 merged, 0 already done, 0 delayed
[scaler_out_0_0 @ 0xf1fe9540] picking bgr24 out of 12 ref:yuv420p alpha:0
[transpose @ 0xf1fe9420] w:848 h:480 dir:1 -> w:480 h:848 rotation:clockwise vflip:0
[scaler_out_0_0 @ 0xf1fe9540] w:480 h:848 fmt:yuv420p sar:0/1 -> w:154 h:308 fmt:bgr24 sar:0/1 flags:0x4
Output #0, image2, to '/storage/emulated/0/Android/data/com.my.package/files/ThumbTemp/thumb1.bmp':
Metadata:
major_brand : mp42
minor_version : 1
compatible_brands: mp41mp42isom
encoder : Lavf58.12.100
Stream #0:0(und), 0, 1001/30000: Video: bmp, 1 reference frame, bgr24(left), 154x308, 0/1, q=2-31, 200 kb/s, 29.97 fps, 29.97 tbn, 29.97 tbc (default)
Metadata:
encoder : Lavc58.18.100 bmp
creation_time : 2018-07-20T19:57:44.000000Z
handler_name : Core Media Video
Side data:
displaymatrix: rotation of -0.00 degrees
cur_dts is invalid (this is harmless if it occurs once at the start per stream)
[h264 @ 0xf1fdbf80] nal_unit_type: 1, nal_ref_idc: 1
cur_dts is invalid (this is harmless if it occurs once at the start per stream)
[h264 @ 0xf1fdc300] nal_unit_type: 1, nal_ref_idc: 1
cur_dts is invalid (this is harmless if it occurs once at the start per stream)
[h264 @ 0xf1fdc680] nal_unit_type: 1, nal_ref_idc: 1
cur_dts is invalid (this is harmless if it occurs once at the start per stream)
[h264 @ 0xf1fdca00] nal_unit_type: 1, nal_ref_idc: 1
cur_dts is invalid (this is harmless if it occurs once at the start per stream)
[h264 @ 0xf1fdcd80] nal_unit_type: 1, nal_ref_idc: 1
cur_dts is invalid (this is harmless if it occurs once at the start per stream)
[h264 @ 0xf1fdd100] nal_unit_type: 1, nal_ref_idc: 1
cur_dts is invalid (this is harmless if it occurs once at the start per stream)
[h264 @ 0xf1fdd480] nal_unit_type: 1, nal_ref_idc: 1
cur_dts is invalid (this is harmless if it occurs once at the start per stream)
Last message repeated 9 times
[out_0_0 @ 0xf1fe94e0] EOF on sink link out_0_0:default.
No more output streams to write to, finishing.
frame= 0 fps=0.0 q=0.0 Lsize=N/A time=00:00:00.00 bitrate=N/A speed= 0x 
video:0kB audio:0kB subtitle:0kB other streams:0kB global headers:0kB muxing overhead: unknown
Input file #0 (/storage/emulated/0/Download/email/VID-20180720-WA0001.mp4):
Input stream #0:0 (video): 16 packets read (153990 bytes); 16 frames decoded; 
Input stream #0:1 (audio): 0 packets read (0 bytes); 
Total: 16 packets (153990 bytes) demuxed
Output file #0 (/storage/emulated/0/Android/data/com.my.package/files/ThumbTemp/thumb1.bmp):
Output stream #0:0 (video): 0 frames encoded; 0 packets muxed (0 bytes); 
Total: 0 packets (0 bytes) muxed
Output file is empty, nothing was encoded (check -ss / -t / -frames parameters if used)
16 frames successfully decoded, 0 decoding errors
[AVIOContext @ 0xf1fbc000] Statistics: 221436 bytes read, 1 seeks


  


• Your guide to cookies, web analytics, and GDPR compliance

  25 février 2020, par Joselyn Khor — Analytics Tips, Privacy, Security
  It’s been almost two years since the GDPR came into effect and turned the online world on its head. Confusion around cookies/cookie consent/cookie compliance remains till today. So we’d like to take this chance to talk more about the supposed “big bad” of the latest century. 

  Online cookies seem to have a bad reputation, but are they as bad as they seem ?

  To start, what are cookies on the internet ?

  An internet cookie a.k.a. an HTTP cookie, is a small piece of data sent from websites that is stored on your computer or mobile when you visit that site.

  Are all cookies bad ?

  No. Cookies themselves are usually harmless as they can’t infect computers with malware. 

  They can also be helpful for both websites who use them and individuals visiting those websites. For example, when online shopping, cookies on ecommerce sites keep track of what you’re shopping for. If you didn’t have that tracking, your cart would be empty every time you moved away from that site.

  For businesses/websites, cookies can be used for authentication (logins) and tracking website user experience. For example, tracking multiple visits to the same site in order to provide better experiences to customers visiting their website.

  

  The not-so-sweet types of cookies :

  Cookies that contain personal data

  Another example of a bad cookie is when cookies contain personal data directly in the cookie itself. For example, when websites store demographics or your name in a cookie ; or when a website stores survey results in a cookie. Use of cookies in these ways is considered bad practice nowadays.

  Third-party cookies
  

  They can be used by websites to learn about your visit and activity across multiple websites. Cookies can enter harmful territory when employed for “big brother” types of tracking i.e. when they’re used to build a virtual fingerprint of individuals after their activity is tracked from website to website. For example most advertising networks create third party cookies in your browser when you view an ad, which lets these advertisers track users across these websites and let companies buy more targeted ads.

  Why does Matomo use cookies ?

  

  For accurate reporting of new and returning visitors. Matomo uses cookies to store some information about visitors between visits. We also use cookies to remember if someone gave consent to tracking, or opted out of tracking. 

  Types of cookies Matomo uses :

  • Matomo by default uses first-party cookies, set on the domain of your site.
  • Cookies created by Matomo start with : _pk_ref, _pk_cvar, _pk_id, _pk_ses. See a list of all Matomo cookies : https://matomo.org/faq/general/faq_146/

  Cookie-less tracking - disable cookies and ensure cookie compliance :

  It’s possible to disable tracking cookies in Matomo by adding a line on the javascript code. When cookies are disabled, Matomo data will become slightly less accurate. Also, when cookies are disabled, there may still be a few cookies created in specific cases.

  If you disable cookies, Matomo tries to detect unique visitors by a fingerprint based on a few browser attributes : operating system, browser, browser plugins, IP address and browser language.

  By disabling tracking cookies, you may also use Matomo without needing to display a cookie consent screen. You can also keep tracking when they reject cookie consent by keeping cookies disabled.

  Cookies and the GDPR

  In some countries and according to the GDPR, websites need to provide a way for users to opt-out of all tracking, in particular tracking cookies.

  The GDPR regulates the use of cookies when they compromise an individual’s privacy. When cookies can identify an individual, it is considered personal data.

  

  Cookie compliance and the GDPR

  To be GDPR compliant you must :

  • Receive user consent before using any cookies (except strictly necessary cookies). Read more on cookies that are “clearly exempt from consent”.
  • Provide accurate and specific information about the data each cookie tracks and its purpose in plain language before consent is received.
  • Document and store consent received from users.
  • Allow users to access your service even if they refuse to allow the use of certain cookies
  • Make it as easy for users to withdraw their consent as it was for them to give their consent in the first place.

  Source : https://gdpr.eu/cookies/

  When does GDPR require cookie consent ?

  The purpose of the GDPR is to give individuals control over their personal data. As such this regulation has provisions and requirements which regulate the processing of personal data to protect the privacy of individuals. 

  This means in order to use cookies, you will sometimes need explicit consent from those individuals.

  When does GDPR not require cookie consent ?

  Then there are many cookies that generally do NOT require consent (Source : https://wikis.ec.europa.eu/display/WEBGUIDE/04.+Cookies). 

  These are :

  • user input cookies, for the duration of a session
  • authentication cookies, for the duration of a session
  • user-centric security cookies, used to detect authentication abuses and linked to the functionality explicitly requested by the user, for a limited persistent duration
  • multimedia content player session cookies, such as flash player cookies, for the duration of a session
  • load balancing session cookies and other technical cookies, for the duration of session
  • user interface customisation cookies, for a browser session or a few hours, when additional information in a prominent location is provided (e.g. “uses cookies” written next to the customisation feature)

  Tracking cookies and consent vs legitimate interest

  

  User consent is not always required :

  We understand that whenever you collect and process personal data, you need – almost always – to ask for their consent. However, there are instances where you have to process data under “legitimate interests”. The GDPR states that processing of personal data is lawful “if processing is necessary for the purposes of the legitimate interests”. This means if you have “legitimate interests” you can avoid asking for consent for collecting and processing personal information. Learn more : https://cookieinformation.com/resources/blog/what-is-legitimate-interest-under-the-gdpr 

  A lawful basis for processing personal data (proceeding with caution) :

  We’ve also written about having a lawful basis for processing personal data under GDPR with Matomo. The caveat here is you need to have a strong argument for legitimate interests. If you are processing personal data which may represent a risk to the final user, then getting consent is, for us, still the right lawful basis. If you are not sure, at the time of writing ICO is providing a tool in order to help you make this decision.

  How is Matomo Analytics GDPR compliant ?

  Matomo can be configured to automatically anonymise data so you don’t process any personal data. This allows you to completely avoid GDPR. If you decide to process personal data, Matomo provides you with 12 steps to easily comply with the GDPR guidelines.

  New developments on cookies and the GDPR

  In the early days of the GDPR, a spate of cookie management platforms (CMPs) popped up to help websites and people comply with GDPR rules around cookies.

  These have become problematic in recent years. Europe’s highest court ruled pre-checked box for cookie boxes does not give enough consent. 

  As well as that, new research suggests most cookie consent pop-ups in the EU fall short of GDPR. A new study called, ‘Dark Patterns after the GDPR’ from MIT, UCL and Aarhus University found that a vast majority of websites aren’t following GDPR rules around cookies. The study found most cookie consent pop-ups in the EU to be undermining the GDPR by finding sneaky ways to convince website visitors to click ‘accept’.

  Disclaimer

  We are not lawyers and don’t claim to be. The information provided here is to help give an introduction to issues you may encounter when dealing cookies. We encourage every business and website to take data privacy seriously and discuss these issues with your lawyer if you have any concerns. 

  Additional resources :

  • How do the cookie rules relate to the GDPR ? 
  • Cookies, the GDPR, and the ePrivacy Directive