[FFmpeg-user] seeking woes

Mon Jun 2 17:00:58 CEST 2014

I've got a 2 hour dvd. I've used vobcopy to transfer it. ffplay (and 
mplayer) can play all two hours.

-rw-r--r--. 1 root  root  6989111296 Jun  2 09:54 BIG21.vob

But when I try to transcode the second half, ffmpeg thinks it's only 59 
minutes long:

  ffmpeg -ss 01:05:00 -i BIG21.vob -threads 4 -an -c:v libx264 -pass 1 
-f mp4 -y /dev/null
ffmpeg version 2.2.git Copyright (c) 2000-2014 the FFmpeg developers
   built on May 24 2014 07:35:17 with gcc 4.8.2 (GCC) 20131212 (Red Hat 
4.8.2-7)
   configuration: --prefix=/usr --bindir=/usr/bin 
--datadir=/usr/share/ffmpeg --libdir=/usr/lib64 --mandir=/usr/share/man 
--shlibdir=/usr/lib64 --extra-cflags='-Ofast -march=native -mtune=native 
-fopenmp -fomit-frame-pointer -pipe' --enable-avresample --enable-static 
--enable-shared --enable-gray --enable-gpl --enable-nonfree 
--enable-version3 --enable-postproc --enable-avfilter 
--enable-avresample --enable-pthreads --enable-x11grab --enable-gray 
--enable-vaapi --enable-hardcoded-tables --enable-libaacplus 
--enable-avisynth --enable-frei0r --enable-libfdk-aac --enable-libgsm 
--enable-libmp3lame --enable-libopenjpeg --enable-libopus 
--enable-librtmp --enable-libschroedinger --enable-libsoxr 
--enable-libspeex --enable-libtheora --enable-libvo-aacenc 
--enable-libvorbis --enable-libvpx --enable-libwebp --enable-libx264 
--enable-libxvid --enable-zlib --disable-debug --cpu=amdfam10 
--arch=x86_64 --enable-pic --enable-libopencv --enable-openssl
   libavutil      52. 86.100 / 52. 86.100
   libavcodec     55. 64.100 / 55. 64.100
   libavformat    55. 40.100 / 55. 40.100
   libavdevice    55. 13.101 / 55. 13.101
   libavfilter     4.  5.100 /  4.  5.100
   libavresample   1.  2.  0 /  1.  2.  0
   libswscale      2.  6.100 /  2.  6.100
   libswresample   0. 19.100 /  0. 19.100
   libpostproc    52.  3.100 / 52.  3.100
Input #0, mpeg, from 'BIG21.vob':
   Duration: 00:59:41.87, start: 0.280633, bitrate: 15609 kb/s
     Stream #0:0[0x1bf]: Data: dvd_nav_packet
     Stream #0:1[0x1e0]: Video: mpeg2video (Main), yuv420p(tv), 720x480 
[SAR 32:27 DAR 16:9], max. 7931 kb/s, 29.83 fps, 59.94 tbr, 90k tbn, 
59.94 tbc
     Stream #0:2[0x80]: Audio: ac3, 48000 Hz, 5.1(side), fltp, 384 kb/s
     Stream #0:3[0x89]: Audio: dts (DTS), 48000 Hz, 5.1(side), fltp, 768 
kb/s
     Stream #0:4[0x82]: Audio: ac3, 48000 Hz, stereo, fltp, 192 kb/s
     Stream #0:5[0x83]: Audio: ac3, 48000 Hz, stereo, fltp, 192 kb/s
     Stream #0:6[0x84]: Audio: ac3, 48000 Hz, stereo, fltp, 192 kb/s
[libx264 @ 0x20eb200] using SAR=32/27
[libx264 @ 0x20eb200] using cpu capabilities: MMX2 SSE2Fast SSSE3 SSE4.2 
AVX XOP FMA4 FMA3 LZCNT BMI1
[libx264 @ 0x20eb200] profile Main, level 3.0
[libx264 @ 0x20eb200] 264 - core 142 r2M ac76440 - H.264/MPEG-4 AVC 
codec - Copyleft 2003-2014 - http://www.videolan.org/x264.html - 
options: cabac=1 ref=1 deblock=1:0:0 analyse=0x1:0 me=dia subme=2 psy=1 
psy_rd=1.00:0.00 mixed_ref=0 me_range=16 chroma_me=1 trellis=0 8x8dct=0 
cqm=0 deadzone=21,11 fast_pskip=1 chroma_qp_offset=0 threads=4 
lookahead_threads=1 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=2 keyint=250 
keyint_min=25 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 '/dev/null':
   Metadata:
     encoder         : Lavf55.40.100
     Stream #0:0: Video: h264 (libx264) ([33][0][0][0] / 0x0021), 
yuv420p, 720x480 [SAR 32:27 DAR 16:9], q=-1--1, pass 1, 29.97 fps, 60k 
tbn, 29.97 tbc
     Metadata:
       encoder         : Lavc55.64.100 libx264
Stream mapping:
   Stream #0:1 -> #0:0 (mpeg2video -> libx264)
Press [q] to stop, [?] for help
frame=    2 fps=0.0 q=-1.0 Lsize=       2kB time=00:00:00.06 bitrate= 
199.7kbits/s dup=1 drop=0
video:1kB audio:0kB subtitle:0kB other streams:0kB global headers:0kB 
muxing overhead: 102.430130%
[libx264 @ 0x20eb200] frame I:1     Avg QP:13.00  size:   117
[libx264 @ 0x20eb200] frame P:1     Avg QP:14.00  size:    24
[libx264 @ 0x20eb200] mb I  I16..4: 99.9%  0.0%  0.1%
[libx264 @ 0x20eb200] mb P  I16..4:  0.0%  0.0%  0.0%  P16..4:  0.0% 
0.0%  0.0%  0.0%  0.0%    skip:100.0%
[libx264 @ 0x20eb200] coded y,uvDC,uvAC intra: 0.0% 0.0% 0.0% inter: 
0.0% 0.0% 0.0%
[libx264 @ 0x20eb200] i16 v,h,dc,p: 97%  0%  3%  0%
[libx264 @ 0x20eb200] i4 v,h,dc,ddl,ddr,vr,hd,vl,hu:  0%  0% 100%  0% 
0%  0%  0%  0%  0%
[libx264 @ 0x20eb200] i8c dc,h,v,p: 100%  0%  0%  0%
[libx264 @ 0x20eb200] Weighted P-Frames: Y:0.0% UV:0.0%
[libx264 @ 0x20eb200] kb/s:16.90

sean