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I have 60Gb of DV footage that I need to store, but 60Gb is WAY too big. I need to transcode it to a lossy format, but I need the resulting video to be robust such that it can be easily edited with a NLV editor later on.

By robust I mean: able to chop it up easily without losing sync. I suppose this has something to do with the regularity of keyframes.

I've read that HuffYUV doesn't work well in Linux (don't know why) and anyway, I think that this won't compress it nearly enough - I need to reduce it to a few Gigs.

I am on Ubuntu, so tools at my disposal are ffmpeg/avconv, Handbrake, etc.

Thanks.

EDIT: here's info about the input:

Input #0, dv, from 'capture001.dv':
  Metadata:
    timecode        : 00:00:00:21
  Duration: 00:13:46.44, start: 0.000000, bitrate: 28800 kb/s
    Stream #0:0: Video: dvvideo, yuv420p, 720x576 [SAR 16:15 DAR 4:3], 
                        28800 kb/s, 25 tbr, 25 tbn, 25 tbc
    Stream #0:1: Audio: pcm_s16le, 32000 Hz, 2 channels, s16, 1024 kb/s
    Stream #0:2: Audio: pcm_s16le, 32000 Hz, 2 channels, s16, 1024 kb/s
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artfulrobot
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1 Answers1

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There are two industry-standard intermediate codecs that I regularly use:

Both are visually lossless and intra-frame only, which means that they can easily be cut on a per-frame basis, and their playback performance is much better than MPEG-style codecs which use (bi-)predictive coding. ProRes can be read by any decent NLE. For DNxHD, there are plugins for Windows and OS X.

With ffmpeg you can encode to ProRes by calling:

ffmpeg -i input.mpg -c:v prores -profile:v 2 output.mov

If you need to map all audio and video channels to the output, use the -map 0 option before the output file name.

The profile setting corresponds to the ProRes profiles Proxy (0), LT (1), Standard (2) and HQ (3). Refer to the link above to see the average bitrates associated with the different profiles. You haven't specified which DV standard your videos have, but for 720x576 video at 25fps, the Proxy profile would result in a 6 GB/hr file.

Note that you cannot do any visually lossless compression with lower bitrate than what the profiles above offer. Your only choice then is to use an intra-frame only compressed H.264 stream, but the encoding time will increase, and if you plan on editing the files, the generation loss might be too high.

slhck
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