Theophile
Apprentice
Joined: 31 Mar 2004
Posts: 285
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 Posted: Wed Nov 29, 2006 4:31 am Post subject: Possible to change file headers? |
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Here's my predicament:
I've been producing a video lecture series and I recently started recording with my Sony HC-90 in LP (90-minute) mode to eliminate tape changes. I've been using kino and dvgrab (the command line utility) to get the video onto my harddrive. For the first such (LP-mode) recording, I used the following command (the same one I've been using successfully with SP-mode tapes) to capture the data:
| Code: | | dvgrab --format dv2 --autosplit --size 0 |
This gave a roughly 10.5 GB file which is on par with the size of the others from previous grabs. But if I try to play the file with mplayer, here's the output:
| Code: | theophile@Backfoot ~/Desktop/DV/pcclass7/main $ mplayer dvgrab-002.avi
MPlayer 1.0pre8-3.3.6 (C) 2000-2006 MPlayer Team
CPU: AMD Athlon(tm) XP 2400+ (Family: 6, Model: 8, Stepping: 1)
CPUflags: MMX: 1 MMX2: 1 3DNow: 1 3DNow2: 1 SSE: 1 SSE2: 0
Compiled with runtime CPU detection.
Warning unknown option cache-prefill at line 147
93 audio & 211 video codecs
Playing dvgrab-002.avi.
Cache fill: 11.91% (999424 bytes)
RAWDV file format detected.
VIDEO: 720x480 24bpp 29.970 fps 0.0 kbps ( 0.0 kbyte/s)
==========================================================================
Opening audio decoder: Raw DV Audio Decoder
Unknown/missing audio format -> no sound
ADecoder init failed
Opening audio decoder: FFmpeg/libavcodec audio decoders
Cannot find codec 'dvaudio' in libavcodec...
ADecoder init failed
ADecoder init failed
Cannot find codec for audio format 0x56444152.
Read DOCS/HTML/en/codecs.html!
==========================================================================
Xv: could not grab port 158
==========================================================================
Opening video decoder: DirectShow video codecs
Decoder supports the following YUV formats: YUY2 UYVY
Decoder is capable of YUV output (flags 0x9)
VDec: vo config request - 720 x 480 (preferred colorspace: Packed YUY2)
Using codec's postprocessing, max q = 4.
VDec: using Packed YUY2 as output csp (no 0)
Movie-Aspect is undefined - no prescaling applied.
VO: 720x480 => 720x480 Packed YUY2
Selected video codec: vfm: dshow (Sony Digital Video (DV))
==========================================================================
Audio: no sound
Starting playback... |
But there is no audio and the video is completely corrupted. It consists solely of hundreds of colored blocks shifting rapidly all over the window, sort of like if you try to play a DRM'ed WMV with mplayer.
I have to assume the A/V streams are in there somewhere, the file is so large. I NEED to get this data as I have since taped over the original footage. ACK!
For whatever it's worth, I have tried working with this kind of situation with another tape, where if I used the above command with dvgrab, the output file would be corrupted as described above, but capturing via kino worked absolutely fine.
As I mentioned, I grabbed the DV from the camera using the command:
| Code: | | dvgrab --format dv2 --autosplit --size 0 |
....and the output is distorted. Then I used Kino to grab another
recording from the same camera, also recorded at LP setting and the
captured output worked just fine.
Here is the output from 'file' on the DV file that plays back correctly:
| Code: | theophile@Backfoot ~/Desktop/DV/pcclass8/main $ file capture001.dv
capture001.dv: DIF (DV) movie file (NTSC) |
Here is the output from the corrupted file:
| Code: | theophile@Backfoot ~/Desktop/DV/pcclass7/main $ file dvgrab-002.avi
dvgrab-002.avi: data |
Is there some way I could change the file header? Or can anyone suggest something else I might do?
I really, really need this footage. Thanks all in advance for the help!
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Monopedilos |
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Multimedia
