Dv

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Page dedicated to extraction and conversion of DV tape, as used in digital camcorder.

Capture

DV tape capture requires a PC with a firewire (IEEE 1394) port.

  • Check installation:
# Check firewire hardware
lspci | grep -i firewire
# 37:09.0 FireWire (IEEE 1394): LSI Corporation FW322/323 [TrueFire] 1394a Controller (rev 70)

# Check kernel modules are loaded
lsmod | grep firewire
# firewire_ohci          40960  0
# firewire_core          65536  7 firewire_ohci
# crc_itu_t              16384  1 firewire_core

# Install some tools
sudo apt install dvgrab gscanbus
# sudo apt install libraw1394-11   # optional

# See if camera is detected
sudo gscanbus

# Add current users to 'video' (must logout / login) to allow access to /dev/fw
sudo usermod -aG video $USER
  • Grab the DV tape
dvgrab -format=dv2 -rewind -autosplit=14400 -srt -size 0 myvideo-
# -format=dv2: recommended format. Alternative: raw (extension .dv)
# -rewing: rewing before capture
# -size 0: Do not split files based on size
# -autosplit=14400: Split file if there is a gap bigger than 4h.
# -srt: generate subtitles with recording date and time.

recording datecode

  • Raw DV files contain recording datecode information (date + time)

Benchmarks

# Source: dv1_tlg_to_jan_2005
 size  | enc fps  | format
-------|----------|----------------------------------------------------------------------
14543M |          | DV
 1489M | 64.1 fps | x264 slow-20-high-3.1
 2082M |  9.4 fps | x265 slow-18-auto-auto
 1815M | 21.0 fps | x265 medium-18-auto-auto
 1215M | 24.1 fps | x265 medium-20-auto-auto
  917M | 27.35 fps| x265 medium-20-auto-auto + strong-intra-smoothing=0:rect=0:aq-mode=1
  • We choose x265-medium-20-auto-auto.
  • Better than the x265-medium-20 with extra options (extra noise).
  • No significant differences compared to best quality file (x265 slow).