Trouble with on-the-fly transcoding of Recordings

[bgowland]

I'm not having any success with transcoding recordings using the web server /transcode?recording=<oid> url. The web request seems to be being processed OK and ffmpeg fires up in a command window. The .ts file is being created and I can see its size periodically increasing but playback never starts. The same resolution and bitrate work fine for Live TV transcoding with the /live?channel=<number> url. Any ideas?

From the web.log (the only two entries)...

Code:

2013-01-19 02:32:59.425    [DEBUG][28]    Got Web Request (192.168.0.3): /transcode    recording=19972&resolution=256x144&bitrate=400k

Code:

2013-01-19 02:32:59.425    [DEBUG][28]    Running: C:\Program Files\NPVR\other\ffmpeg.exe -y -v 0 -i D:\nPVR\Horizon\Horizon_20120730_21002200.ts -f mpegts -acodec libfaac -ar 48000 -ac 2 -ab 64k -s 256x144 -vcodec libx264 -b 400k -flags +loop -cmp +chroma -refs 1 -coder 0 -me_range 16 -keyint_min 25 -sc_threshold 40 -i_qfactor 0.71 -bt 200k -maxrate 96k -bufsize 96k -rc_eq 'blurCplx^(1-qComp)' -qcomp 0.6 -qmin 10 -qmax 51 -qdiff 4 -level 30 -aspect 256:144 -g 30 -async 2  D:\nPVR\live-tHorizon-3988-29.ts

Cheers,
Brian

[sub]

Have you tried running that ffmpeg command line? I'm curious if it runs or gives some error.

[bgowland]

I hadn't thought of running it manually. Doh. OK, the following is what I see when running it. I don't think there's anything out of the ordinary but I'm no expert with ffmpeg.

Code:

FFmpeg version SVN-r18639, Copyright (c) 2000-2009 Fabrice Bellard, et al.
  configuration: --enable-memalign-hack --enable-postproc --enable-gpl --enable-
libfaac --enable-libfaad --enable-libgsm --enable-libmp3lame --enable-libvorbis
--enable-libtheora --enable-libx264 --enable-libxvid --disable-ffserver --enable
-avisynth --enable-pthreads
  libavutil     50. 3. 0 / 50. 3. 0
  libavcodec    52.27. 0 / 52.27. 0
  libavformat   52.32. 0 / 52.32. 0
  libavdevice   52. 2. 0 / 52. 2. 0
  libswscale     0. 7. 1 /  0. 7. 1
  libpostproc   51. 2. 0 / 51. 2. 0
  built on Apr 21 2009 13:44:38, gcc: 4.2.4 (TDM-1 for MinGW)

Seems stream 0 codec frame rate differs from container frame rate: 50.00 (50/1)
-> 25.00 (25/1)
Input #0, mpegts, from 'D:\nPVR\Horizon\Horizon_20120730_21002200.ts':
  Duration: 01:07:03.40, start: 31169.761133, bitrate: 4303 kb/s
  Program 4287
    Stream #0.0[0xc9]: Video: mpeg2video, yuv420p, 720x576 [PAR 64:45 DAR 16:9],
15000 kb/s, 25 tbr, 90k tbn, 50 tbc
    Stream #0.1[0xca](eng): Audio: mp2, 48000 Hz, stereo, s16, 192 kb/s
    Stream #0.2[0xce](eng): Audio: mp3, 0 channels, s16
    Stream #0.3[0xcd](eng): Subtitle: dvbsub
[libx264 @ 0x1811010]using SAR=1/1
[libx264 @ 0x1811010]using cpu capabilities: MMX2 SSE2 SSE3 Cache64
[libx264 @ 0x1811010]max bitrate less than average bitrate, ignored.
[libx264 @ 0x1811010]profile Baseline, level 3.0
Output #0, mpegts, to 'D:\nPVR\live-tHorizon-3988-29.ts':
    Stream #0.0: Video: libx264, yuv420p, 256x144 [PAR 1:1 DAR 16:9], q=10-51, 4
00 kb/s, 90k tbn, 25 tbc
    Stream #0.1(eng): Audio: libfaac, 48000 Hz, stereo, s16, 64 kb/s
Stream mapping:
  Stream #0.0 -> #0.0
  Stream #0.1 -> #0.1
Press [q] to stop encoding

I left it to run a short while and checked the .ts file had been created and was growing steadily then hit 'q' which produced the following results.

Code:

frame= 3483 fps= 35 q=-2.0 Lsize=    9327kB time=138.77 bitrate= 550.6kbits/s

video:6924kB audio:1087kB global headers:0kB muxing overhead 16.425775%
[libx264 @ 0x1811010]slice I:145   Avg QP:16.93  size:  8387
[libx264 @ 0x1811010]slice P:3338  Avg QP:19.47  size:  1758
[libx264 @ 0x1811010]mb I  I16..4: 13.3%  0.0% 86.7%
[libx264 @ 0x1811010]mb P  I16..4:  5.1%  0.0%  0.0%  P16..4: 77.9%  0.0%  0.0%
0.0%  0.0%    skip:17.0%
[libx264 @ 0x1811010]final ratefactor: 16.55
[libx264 @ 0x1811010]SSIM Mean Y:0.9874544
[libx264 @ 0x1811010]kb/s:406.8

Again I can't see anything odd other than fps=35 or is that the rate it was processing the input file (a bit slow if that's the case).