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I have a video file acquired from Hikvision's NVR connected to IP cameras. The method used to download this video was Hikvision NVR's internal API that produced a flawed video file in several ways:

  1. Duration of the video file is wrong (as seen in Mediainfo or VLC). My guess is this happens due to NVR storing video files in chunks and when attempting to download video by supplying specific start time and end time to NVR's API the software just creates a new video file in memory by extracting the needed parts from stored video and attaching the original video file's duration to the newly created one.

  2. Audio cannot be played in most media players including VLC.

I have tried converting the video file using ffmpeg with different settings to try and fix these issues but the output video still has the same problems. What's interesting is that ffmpeg's ffplay is able to play the video file perfectly with sound and no disruptions. Therefore I figured there must be a way to convert the video file to normalize it for other players as well.

Mediainfo output of the video file in question:

General
CompleteName                     : C:\DownLoad\1.mp4
Format                           : MPEG-PS
FileSize/String                  : 8.60 MiB
Duration/String                  : 2 h 7 min
OverallBitRate/String            : 9 395 b/s
FileExtension_Invalid            : mpeg mpg m2p vob pss evo

Video
ID/String                        : 224 (0xE0)
Format                           : AVC
Format/Info                      : Advanced Video Codec
Format_Profile                   : Baseline@L4
Format_Settings                  : 1 Ref Frames
Format_Settings_CABAC/String     : No
Format_Settings_RefFrames/String : 1 frame
Format_Settings_GOP              : M=1, N=30
Duration/String                  : 2 min 0 s
Width/String                     : 1 920 pixels
Height/String                    : 1 080 pixels
DisplayAspectRatio/String        : 16:9
FrameRate_Mode/String            : Variable
ColorSpace                       : YUV
ChromaSubsampling/String         : 4:2:0
BitDepth/String                  : 8 bits
ScanType/String                  : Progressive

Audio
ID/String                        : 192 (0xC0)
Format                           : MPEG Audio
Duration/String                  : 2 h 7 min
Compression_Mode/String          : Lossy
Video_Delay/String               : -33 min 40 s

Output of ffmpeg:

C:\ffmpeg\bin>ffmpeg -i C:\DownLoad\1.mp4  -c:v libx264 -preset fast -crf 30 -b:v 75k -c:a aac -strict experimental -movflags faststart -threads 0 C:\DownLoad\2.mp4
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 --enable-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-libfreetype --enable-libgme --enable-libgsm --enable-libilbc --enable-libmodplug --enable-libmp3lame --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libopenh264 --enable-libopenjpeg --enable-libopus --enable-librtmp --enable-libsnappy --enable-libsoxr --enable-libspeex --enable-libtheora --enable-libtwolame --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, mpeg, from 'C:\DownLoad\1.mp4':
  Duration: 02:07:57.93, start: 789.820800, bitrate: 9 kb/s
    Stream #0:0[0x1e0]: Video: h264 (Baseline), yuv420p(progressive), 1920x1080, 25 fps, 25 tbr, 90k tbn, 50 tbc
    Stream #0:1[0x1c0]: Audio: pcm_mulaw, 8000 Hz, mono, s16, 64 kb/s
File 'C:\DownLoad\2.mp4' already exists. Overwrite ? [y/N] y
Stream mapping:
  Stream #0:0 -> #0:0 (h264 (native) -> h264 (libx264))
  Stream #0:1 -> #0:1 (pcm_mulaw (native) -> aac (native))
Press [q] to stop, [?] for help
[aac @ 0000000002cd0280] Too many bits 8832.000000 > 6144 per frame requested, clamping to max
[libx264 @ 0000000002514c80] using cpu capabilities: MMX2 SSE2Fast LZCNT SSSE3 SSE4.2 AVX XOP FMA4
[libx264 @ 0000000002514c80] profile High, level 4.0
[libx264 @ 0000000002514c80] 264 - core 150 r2833 df79067 - H.264/MPEG-4 AVC codec - Copyleft 2003-2017 - http://www.videolan.org/x264.html - options: cabac=1 ref=2 deblock=1:0:0 analyse=0x3:0x113 me=hex subme=6 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=12 lookahead_threads=2 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=1 keyint=250 keyint_min=25 scenecut=40 intra_refresh=0 rc_lookahead=30 rc=crf mbtree=1 crf=30.0 qcomp=0.60 qpmin=0 qpmax=69 qpstep=4 ip_ratio=1.40 aq=1:1.00
Output #0, mp4, to 'C:\DownLoad\2.mp4':
  Metadata:
    encoder         : Lavf57.73.100
    Stream #0:0: Video: h264 (libx264) ([33][0][0][0] / 0x0021), yuv420p, 1920x1080, q=-1--1, 75 kb/s, 25 fps, 12800 tbn, 25 tbc
    Metadata:
      encoder         : Lavc57.99.100 libx264
    Side data:
      cpb: bitrate max/min/avg: 0/0/75000 buffer size: 0 vbv_delay: -1
    Stream #0:1: Audio: aac (LC) ([64][0][0][0] / 0x0040), 8000 Hz, mono, fltp, 48 kb/s
    Metadata:
      encoder         : Lavc57.99.100 aac
[mp4 @ 00000000010e9e00] Starting second pass: moving the moov atom to the beginning of the file speed= 116x
frame= 3269 fps= 66 q=-1.0 Lsize=   11086kB time=01:34:24.38 bitrate=  16.0kbits/s dup=269 drop=0 speed= 115x
video:10429kB audio:592kB subtitle:0kB other streams:0kB global headers:0kB muxing overhead: 0.594114%
[libx264 @ 0000000002514c80] frame I:14    Avg QP:21.86  size: 59795
[libx264 @ 0000000002514c80] frame P:833   Avg QP:24.81  size:  8993
[libx264 @ 0000000002514c80] frame B:2422  Avg QP:28.70  size:   970
[libx264 @ 0000000002514c80] consecutive B-frames:  1.0%  0.2%  1.4% 97.4%
[libx264 @ 0000000002514c80] mb I  I16..4: 18.9% 66.3% 14.8%
[libx264 @ 0000000002514c80] mb P  I16..4:  4.0%  7.7%  0.4%  P16..4: 16.2%  2.0%  0.6%  0.0%  0.0%    skip:69.1%
[libx264 @ 0000000002514c80] mb B  I16..4:  0.6%  0.2%  0.0%  B16..8:  5.5%  0.1%  0.0%  direct: 0.7%  skip:92.9%  L0:44.0% L1:55.0% BI: 1.0%
[libx264 @ 0000000002514c80] 8x8 transform intra:59.0% inter:83.3%
[libx264 @ 0000000002514c80] coded y,uvDC,uvAC intra: 25.3% 36.1% 7.7% inter: 1.0% 2.3% 0.1%
[libx264 @ 0000000002514c80] i16 v,h,dc,p: 23% 24% 43% 10%
[libx264 @ 0000000002514c80] i8 v,h,dc,ddl,ddr,vr,hd,vl,hu: 37% 26% 23%  2%  2%  3%  2%  3%  3%
[libx264 @ 0000000002514c80] i4 v,h,dc,ddl,ddr,vr,hd,vl,hu: 43% 23% 12%  4%  4%  5%  4%  4%  2%
[libx264 @ 0000000002514c80] i8c dc,h,v,p: 81%  7%  9%  3%
[libx264 @ 0000000002514c80] Weighted P-Frames: Y:1.0% UV:0.0%
[libx264 @ 0000000002514c80] ref P L0: 73.6% 26.4%
[libx264 @ 0000000002514c80] ref B L0: 80.9% 19.1%
[libx264 @ 0000000002514c80] ref B L1: 90.0% 10.0%
[libx264 @ 0000000002514c80] kb/s:653.30
[aac @ 0000000002cd0280] Qavg: 64512.656

C:\ffmpeg\bin>

Download link to sample:

https://www.dropbox.com/s/9ccptsuiqk2ntsv/1.zip?dl=0

This sample is exactly 2 minutes long, but VLC will tell you otherwise.

  • All 2 minutes and 8 seconds play perfectly on VLC for Android. There's certainly some odd values reported by ffmpeg. Could we trouble you for an ffprobe output too? - The video is a bit blocky for the Bitrate but it plays without a hiccup. – Rob Dec 13 '17 at 0:13
  • @Rob I have actually solved the problem by extracting the audio from this file and then merging and converting it with the original video. I forgot to post the answer here, but I will do so now. – astralmaster Dec 13 '17 at 8:01
  • Good going. After some more testing it is permissible to mark your own answer to your question as correct. – Rob Dec 13 '17 at 8:34
1

I was able to produce a normalized video file by doing the following:

  1. Extracting audio stream from my MPEG-PS video file using ffmpeg and using -acodec aac.

  2. Removing audio stream from the original MPEG-PS video file using ffmpeg and -v:c copy and using -t option to specify the actual duration of the video.

  3. Merging the two files together.

Result is a file that is playable in any video player. Tested on VLC, MPC-HC.

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