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• split video (avi/h264) on keyframe

  30 novembre 2012, par m.sr

  Hallo.

  I have a big video file. ffmpeg, tcprobe and other tool say, it is an h264-stream in an AVI-container.

  Now i'd like to cut out small chunks form the video.

  1. Problem : The index of the video seam corrupted/destroyed. I kind of fixed this via mplayer -forceidx -saveidx <indexfile> <bigvideofile></bigvideofile></indexfile>. The Problem here is, that I'm now stuck with mplayer/mencoder which can use this index file via -loadidx <indexfile></indexfile>. I have tried correcting the index like described in man aviindex (mplayer -frames 0 -saveidx mpidx broken.avi ; aviindex -i mpidx -o tcindex ; avimerge -x tcindex -i broken.avi -o fixed.avi), but this didn't fix my video - meaning that most tools i've tested couldn't search in the video file.

  2. Problem : I cut out parts of the video via following command : mencoder -loadidx in.idx -ss 8578 -endpos 20 -oac faac -ovc x264 -sws 9 -lavfopts format=mp4 -x264encopts <lotsofopts> -of lavf -vf scale=800:-10,harddup in.avi -o out.mp4</lotsofopts>. Now here the problem is, that some videos are corrupted at the beginning. I think this is because the fact, that i do not necessarily cut at keyframe.

  Questions :

  1. What is the best way to fix the index of an avi "inline" so that every tool can again work as expected with it ?

  2. How can i split at the keyframes ? Is there an mencoder-option for this ?

  3. Are Keyframes coming in a frequency ? How to find out this frequency ? (So with a bit of math it should be possible to calculate the next keyframe and cut there)

  4. Is ther perhaps some completely other way to split this movie ? Doing it by hand is no option, i've to cut out 1000+ chunks ...

  Thanks a lot !

• HLS With discontinuity stuck in buffer

  25 mars 2021, par Vittorio Malandrino

  We are using JWPlayer 8.9.0 and we are trying to insert advertisements in our videos.
We are using EXT-X-DISCONTINUITY but apparently, when we get to the point of starting our advertising, the player stops showing a buffer status.

  



  This is an example of our playlist :

  



  #EXTM3U
#EXT-X-VERSION:3
#EXT-X-MEDIA-SEQUENCE:0
#EXT-X-TARGETDURATION:16
#EXT-X-PLAYLIST-TYPE:VOD
#EXTINF:14.557178,
https://slave2.example.com/hls/output1/output_000.ts
#EXTINF:1.376467,
https://slave3.example.com/hls/output1/output_001.ts
#EXT-X-DISCONTINUITY
#EXTINF:8.050244,
https://slave2.example.com/hls/HLSad/output_000.ts
#EXTINF:4.880200,
https://slave2.example.com/hls/HLSad/output_001.ts
#EXTINF:7.090889,
https://slave2.example.com/hls/HLSad/output_002.ts
#EXTINF:5.881267,
https://slave2.example.com/hls/output1/output_002.ts
#EXTINF:5.672711,
https://slave3.example.com/hls/output1/output_003.ts
#EXT-X-DISCONTINUITY
#EXTINF:8.050244,
https://slave2.example.com/hls/HLSad/output_000.ts
#EXTINF:4.880200,
https://slave2.example.com/hls/HLSad/output_001.ts
#EXTINF:7.090889,
https://slave2.example.com/hls/HLSad/output_002.ts
#EXTINF:5.714422,
https://slave2.example.com/hls/output1/output_004.ts
#EXTINF:4.755067,
https://slave3.example.com/hls/output1/output_005.ts
[...]
#EXT-X-ENDLIST


  



  This is what the JS console tells us :

  



  [log] > audio sampling rate : 48000
9512e6e5-eff6-4f75-806f-a367785315b7:1 [log] > manifest codec:undefined,ADTS data:type:2,sampleingIndex:3[48000Hz],channelConfig:2
9512e6e5-eff6-4f75-806f-a367785315b7:1 [log] > parsed codec:mp4a.40.5,rate:48000,nb channel:2
9512e6e5-eff6-4f75-806f-a367785315b7:1 [log] > audio sampling rate : 48000
9512e6e5-eff6-4f75-806f-a367785315b7:1 [log] > AVC:59 ms overlapping between fragments detected
9512e6e5-eff6-4f75-806f-a367785315b7:1 [log] > Video/PTS/DTS adjusted: 15958/15933,delta:-59 ms


  



  While the Chrome Media console says :

  



  1.414   kPlay   
{}

17.280  kBufferingStateChanged  
{audio_buffering_state: {reason: "DEMUXER_UNDERFLOW", state: "BUFFERING_HAVE_NOTHING"}}

17.280  kBufferingStateChanged  
{,…}
pipeline_buffering_state: {for_suspended_start: false, reason: "DEMUXER_UNDERFLOW", state: "BUFFERING_HAVE_NOTHING"}
for_suspended_start: false
reason: "DEMUXER_UNDERFLOW"
state: "BUFFERING_HAVE_NOTHING"



  



  Considering that the two videos that we are going to "merge" in the playlist have the same audio / video characteristics (codecs, bitrate, resolution etc.), why is this not working ?
Thank you

  


• hevc : deobfuscate slice/tile boundary handling for DBF

  27 juillet 2014, par Anton Khirnov

  hevc : deobfuscate slice/tile boundary handling for DBF
  Use named constants instead of magic numbers, avoid using variables with
  
  inverse meaning from what their name implies.
  

  • [DH] libavcodec/hevc.c
  • [DH] libavcodec/hevc.h
  • [DH] libavcodec/hevc_filter.c