Den 06.05.2025 22:54, skrev Andrew Randrianasulu:


вт, 6 мая 2025 г., 23:49 Terje J. Hanssen <terjejhanssen@gmail.com>:


Den 05.05.2025 16:05, skrev Andrew Randrianasulu:


пн, 5 мая 2025 г., 17:00 Andrew Randrianasulu <randrianasulu@gmail.com>:


пн, 5 мая 2025 г., 16:26 Terje J. Hanssen via Cin <cin@lists.cinelerra-gg.org>:
I consider to make a second preservation backup for archiving my Analog S-video and HDV footages on tapes to lossless compressed FFV1.MKV files stored on large USB3 expansion disks. Also ffv1 HW (vulkan) decoding (next and encoding (later?) are of interest in this context.

Related previous threads
https://www.mail-archive.com/cin@lists.cinelerra-gg.org/msg05547.html
https://www.mail-archive.com/cin@lists.cinelerra-gg.org/msg03791.html
https://www.mail-archive.com/cin@lists.cinelerra-gg.org/msg05547.html

I adapt simply the last ffmpeg mpeg-2 code line to a first ffv1, version 3 test, 10 sec file

ffmpeg -hide_banner -f v4l2 -input_format yuyv422 -video_size 720x576 -framerate 50 -i /dev/video0 -f alsa -ac 2 -i hw:CARD=UHD,DEV=0 -c:v ffv1 -level 3 -c:a pcm_s16le -t 10 720x576_50fps+alsa_ms2130_ffv1-3+pcm.mkv
Input #0, video4linux2,v4l2, from '/dev/video0':
  Duration: N/A, start: 351.803278, bitrate: 331776 kb/s
  Stream #0:0: Video: rawvideo (YUY2 / 0x32595559), yuyv422, 720x576, 331776 kb/s, 50 fps, 50 tbr, 1000k tbn
[aist#1:0/pcm_s16le @ 0x555a99736cc0] Guessed Channel Layout: stereo
Input #1, alsa, from 'hw:CARD=UHD,DEV=0':
  Duration: N/A, start: 1746445045.742179, bitrate: 1536 kb/s
  Stream #1:0: Audio: pcm_s16le, 48000 Hz, stereo, s16, 1536 kb/s
Stream mapping:
  Stream #0:0 -> #0:0 (rawvideo (native) -> ffv1 (native))
  Stream #1:0 -> #0:1 (pcm_s16le (native) -> pcm_s16le (native))
Press [q] to stop, [?] for help
Output #0, matroska, to '720x576_50fps+alsa_ms2130_ffv1-3+pcm.mkv':
  Metadata:
    encoder         : Lavf61.7.100
  Stream #0:0: Video: ffv1 (FFV1 / 0x31564646), yuv422p(tv, progressive), 720x576, q=2-31, 200 kb/s, 50 fps, 1k tbn
      Metadata:
        encoder         : Lavc61.19.101 ffv1
  Stream #0:1: Audio: pcm_s16le ([1][0][0][0] / 0x0001), 48000 Hz, stereo, s16, 1536 kb/s
      Metadata:
        encoder         : Lavc61.19.101 pcm_s16le
[out#0/matroska @ 0x555a99736f40] video:57467KiB audio:1875KiB subtitle:0KiB other streams:0KiB global headers:0KiB muxing overhead: 0.069226%
frame=  500 fps= 50 q=-0.0 Lsize=   59383KiB time=00:00:10.00 bitrate=48646.9kbits/s speed=0.998x

----------

du -sh *
58M    720x576_50fps+alsa_ms2130_ffv1-3+pcm.mkv

----------

ffprobe -hide_banner 720x576_50fps+alsa_ms2130_ffv1-3+pcm.mkv
Input #0, matroska,webm, from '720x576_50fps+alsa_ms2130_ffv1-3+pcm.mkv':
  Metadata:
    ENCODER         : Lavf61.7.100
  Duration: 00:00:10.00, start: 0.000000, bitrate: 48646 kb/s
  Stream #0:0: Video: ffv1 (FFV1 / 0x31564646), yuv422p(tv, progressive), 720x576, 50 fps, 50 tbr, 1k tbn
      Metadata:
        ENCODER         : Lavc61.19.101 ffv1
        DURATION        : 00:00:10.000000000
  Stream #0:1: Audio: pcm_s16le, 48000 Hz, 2 channels, s16, 1536 kb/s
      Metadata:
        ENCODER         : Lavc61.19.101 pcm_s16le
        DURATION        : 00:00:10.000000000

------------        

mediainfo 720x576_50fps+alsa_ms2130_ffv1-3+pcm.mkv
General
Unique ID                                : 158479793538002634101121179263279280827 (0x773A19163BEA6038DF448CE1529BB2BB)
Complete name                            : 720x576_50fps+alsa_ms2130_ffv1-3+pcm.mkv
Format                                   : Matroska
Format version                           : Version 4
File size                                : 58.0 MiB
Duration                                 : 10 s 0 ms
Overall bit rate mode                    : Variable
Overall bit rate                         : 48.6 Mb/s
Frame rate                               : 50.000 FPS
Writing application                      : Lavf61.7.100
Writing library                          : Lavf61.7.100
ErrorDetectionType                       : Per level 1

Video
ID                                       : 1
Format                                   : FFV1
Format version                           : Version 3.4
Format settings, Slice count             : 4 slices per frame
Codec ID                                 : V_MS/VFW/FOURCC / FFV1
Duration                                 : 10 s 0 ms
Bit rate mode                            : Variable
Bit rate                                 : 46.1 Mb/s
Width                                    : 720 pixels
Height                                   : 576 pixels
Display aspect ratio                     : 5:4
Frame rate mode                          : Constant
Frame rate                               : 50.000 FPS
Color space                              : YUV
Chroma subsampling                       : 4:2:2
Bit depth                                : 8 bits
Scan type                                : Progressive
Compression mode                         : Lossless
Bits/(Pixel*Frame)                       : 2.225
Stream size                              : 55.0 MiB (95%)
Writing library                          : Lavc61.19.101 ffv1
Default                                  : No
Forced                                   : No
Color range                              : Limited
coder_type                               : Golomb Rice
ErrorDetectionType                       : Per slice

Audio
ID                                       : 2
Format                                   : PCM
Format settings                          : Little / Signed
Codec ID                                 : A_PCM/INT/LIT
Duration                                 : 10 s 0 ms
Bit rate mode                            : Constant
Bit rate                                 : 1 536 kb/s
Channel(s)                               : 2 channels
Sampling rate                            : 48.0 kHz
Bit depth                                : 16 bits
Stream size                              : 1.83 MiB (3%)
Writing library                          : Lavc61.19.101 pcm_s16le
Default                                  : No
Forced                                   : No
---------------------------------

As seen above the "default" Chroma subsampling  is yuv422p or 4:2:2 with Bit depth: 8 bits

As ffv1 seemingly also does support yuv422p10le ffmpeg, I wonder if yuv422p is limited by the input from HDMI capture/AV converter?
Can possibly yuv422p10le possibly be achieved by adding -pix_fmt 10 og similar syntax to the ffmpeg line?

you can try  different -input_format, but I suspect 10bit video over v4l2 at best uncommon ... While hdmi itself supports 10bit digital signal, I suspect  non-pro capture devices usually limited to 8bit?


I can't see 10bit yuy2 format listed here, so probably even if hw/driver support it ffmpeg will not ...

Yes, It seems this also is the case.
Even I got a few 10-bits "-input_format" y210 and p210 accepted by ffmpeg, in both cases the output format "defaulted" to the same 'yuv422p'.
What also surprised me, the filesizes at the same time also was reduced to 77%

du -sh *
45M    720x576_50fps_p210+alsa_ms2130_ffv1-3+pcm.mkv
45M    720x576_50fps_y210+alsa_ms2130_ffv1-3+pcm.mkv
58M    720x576_50fps_yuyv422+alsa_ms2130_ffv1-3+pcm.mkv

I guess they 10 bit but 4:2:0 subsampling?

Noop, according to mediainfo all have

Color space                              : YUV
Chroma subsampling                       : 4:2:2
Bit depth                                : 8 bits

By the way, I acknowledge this limit at the hand.
10-Bit Video is recommended for Analog Tape Transfer due to color shades and branding
https://www.archivalworks.com/blog/10-bit-video-transfer

But I expect also 8-bit 422 transfer to FFV1 opt for some better quality than the current 8-bit 420 DV25 files (converted from PAL S-video) and the HDV.m2t backup files.
IMO direct playback of S-vdeo tapes has visual better brightness than the converted DV files.
It remains also to verify if playing 1080i50 HDV tapes via HDMI will be up-scaled to 422 and 720p, according to Steve Mullen' FX7 handbook.

To continue I copy with from my old, initial post at
https://www.mail-archive.com/cin@lists.cinelerra-gg.org/msg05547.html


Does all FFV1 level 3 versions work with lossless compression for 422 video?

I have not yet found a definitiv ffmpeg FFV1 v 3 syntax guide for SD and HDV capturing and hope for suggestions and comments regarding the examples below:

3.1 FFmpeg recipe (PAL)

   ffmpeg -i VIDEO_IN \

       -c:v ffv1 -level 3 -coder 1 -context 0 -slices 24 -slicecrc 1 \
       -color_primaries bt470bg \
       -color_trc bt709 \
       -colorspace bt470bg \
       -color_range mpeg \
       -map 0 \
       -top 1 \
       -c:a copy \
       -g 1 -pix_fmt + \
       VIDEO_OUT.mkv


3.2 Reference Example
https://trac.ffmpeg.org/wiki/Encode/FFV1#Examples

    Copy audio "as-is" and use FFV1.3 as video codec.
    Parameters are 8 threads, coder=1, context=1, GOP-size=1, 24 slices and slice-CRC on:

 
    ffmpeg -i <input_video>     \
        -acodec   copy          \
        -vcodec   ffv1 -level 3 \
        -threads  8             \
        -coder    1             \
        -context  1             \
        -g        1             \
        -slices  24             \
        -slicecrc 1             \
        <output_video>


3.3 Various Encoding examples for Video capture from USB camera /dev/video0:
ffmpeg -f v4l2 -framerate 25 -video_size 720x576 -i /dev/video0 output_data.mkv ffmpeg -f v4l2 -framerate 25 -video_size 720x576 -i /dev/video0 -codec:v ffv1 -codec:a pcm_s16le \
    -f matroska  output_video.mkv


Check that video is captured properly using ffplay:

ffmpeg -ar 44100 -thread_queue_size 1024 -f alsa -i $AUDIO \     -r 25 -thread_queue_size 1024 -i $VIDEO \     -codec copy -f matroska  - | ffplay


- Check the overall flow using ffplay before capturing:

ffmpeg -ar 44100 -thread_queue_size 1024 -f alsa -i $AUDIO \     -itsoffset -0.5 -r 25 -thread_queue_size 1024 -i $VIDEO \
    -filter_complex 'channelmap=FL-0' -filter_complex 'crop=w=700:h=556:x=8:y=0' \
    -map 1:v  -map 0:a -codec:v ffv1 -codec:a pcm_s16le \     -f matroska  - | ffplay -




why we can't have both ;) I mean, it all depend on hw, and now board wired ... If there was relatively popular capture board I am sure someone tried to push core linux kernel bits upstream ...


but hw design is harder than it looks.






But of course you better to doublecheck what v4l2 tools says ...

So far no other  pixel formats found:

v4l2-ctl -V
Format Video Capture:
    Width/Height      : 720/576
    Pixel Format      : 'YUYV' (YUYV 4:2:2)
    Field             : None
    Bytes per Line    : 1440
    Size Image        : 829440
    Colorspace        : sRGB
    Transfer Function : Rec. 709
    YCbCr/HSV Encoding: ITU-R 601
    Quantization      : Default (maps to Limited Range)
    Flags             :




Sorry for "too generic" answer, few years ago I/we looked into "direct RF capture" and there getting 10bit signal was possible, with custom hardware, slow offline processing and invasive hoockup to VCR's internals.

Similar I bought and captured a few ProRes422 HQ few files in 2016 with Blackmagic Design's HyperDeck Shuttle+AD miniconverter+SSD recorder.
But some years later, BMD's fw support became EOL, and the devices became non-working :(