Using

  • For playback, a CCD-TRV118 (NTSC)
  • For A/D conversion
  • For compression, ffmpeg on Linux

A/D conversion

To optimize quality, convert to raw video using the following EZ Grabber settings

  • Video:
    • Video format: NTSC_M
    • Video source = S-Video
    • Picture adjustment: All 127
  • Record:
    • Record format: AVI

The older the cassettes, the shorter the conversion interval needed to avoid synchronization problems. Intervals between 10 and 30 minutes worked OK.

Result is raw video:

$ ffmpeg -i raw-video.avi
[avi @ 0x1293960] non-interleaved AVI
Guessed Channel Layout for  Input Stream #0.0 : stereo
Input #0, avi, from 'raw-video.avi':
  Duration: 00:31:06.37, start: 0.000000, bitrate: 167412 kb/s
    Stream #0:0: Audio: pcm_s16le ([1][0][0][0] / 0x0001), 48000 Hz, 2 channels, s16, 1536 kb/s
    Stream #0:1: Video: rawvideo (UYVY / 0x59565955), uyvy422, 720x480, 165644 kb/s, 29.96 fps, 29.96 tbr, 29.96 tbn, 29.96 tbc
At least one output file must be specified

Only one audio channel actually contains audio, the other channel is empty.

Compression

Compress video and pack in a Matroska container with uncompressed audio, mapping the audio left channel to a single mono channel. Using H.264 because of its good quality, size and compatibility.

$ ffmpeg -i raw-video.avi -c:v libx264 -preset slow -crf 17 -c:a pcm_s16le -map_channel 0.0.0 video.mkv

Result:

$ ffmpeg -i video.mkv
Guessed Channel Layout for  Input Stream #0.1 : mono
Input #0, matroska,webm, from 'vido.mkv':
  Metadata:
    ENCODER         : Lavf56.4.101
  Duration: 00:31:07.09, start: 0.067000, bitrate: 7049 kb/s
    Stream #0:0: Video: h264 (High 4:2:2), yuv422p, 720x480, SAR 1:1 DAR 3:2, 29.98 fps, 29.98 tbr, 1k tbn, 59.97 tbc (default)
    Metadata:
      ENCODER         : Lavc56.1.100 libx264
    Stream #0:1: Audio: pcm_s16le, 48000 Hz, 1 channels, s16, 768 kb/s (default)
    Metadata:
      ENCODER         : Lavc56.1.100 pcm_s16le
 At least one output file must be specified

Script

Compress raw video into Matroska container, see ffmpeg & Digitizing VHS cassettes.

Audio

To extract the raw audio from the Matroska container without encoding

$ ffmpeg -i video.mkv -f s16le -acodec pcm_s16le video_audio.raw

Note that the arguments to f and acodec options match the description of the audio stream (#0.1) in the output of ffmpeg -i video.mkv. The extracted audio is literally raw:

$ file video_audio.raw
video_audio.raw: data

Neither ffmpeg nor vlc know how to deal with such file without the user providing some help. ffmpeg thinks it’s video data

$ ffmpeg -i video_audio.raw
[image2 @ 0x1de86a0] Format image2 detected only with low score of 5, misdetection possible!
[rawvideo @ 0x1de9ac0] Invalid pixel format.
[image2 @ 0x1de86a0] Failed to open codec in av_find_stream_info
[rawvideo @ 0x1de9ac0] Invalid pixel format.
[image2 @ 0x1de86a0] Could not find codec parameters for stream 0 (Video: rawvideo, none): unspecified size
Consider increasing the value for the 'analyzeduration' and 'probesize' options
video_audio.raw: could not find codec parameters
Input #0, image2, from 'video_audio.raw':
  Duration: 00:00:00.04, start: 0.000000, bitrate: N/A
    Stream #0:0: Video: rawvideo, none, 25 tbr, 25 tbn, 25 tbc
At least one output file must be specified

vlc will just show you an error. Providing a little guidance works, for example below options will result in vlc correctly playing the file

$ vlc --demux=rawaud --rawaud-samplerate 44100 --rawaud-channels 1 video_audio.raw &

Specify the input format to ffmpeg like this

$ ffmpeg -f s16le -i video_audio.raw
[s16le @ 0x7166a0] Estimating duration from bitrate, this may be inaccurate
Guessed Channel Layout for  Input Stream #0.0 : mono
Input #0, s16le, from 'video_audio.raw':
  Duration: 00:11:37.56, bitrate: 705 kb/s
    Stream #0:0: Audio: pcm_s16le, 44100 Hz, 1 channels, s16, 705 kb/s
At least one output file must be specified

Note that the description of the stream matches the output of ffmpeg -i video.mkv in the previous section. The duration is different because it’s actually a different video than the previous section.

References