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<div class="moz-cite-prefix">Den 03.05.2025 13:00, skrev Terje J.
Hanssen:<br>
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<div class="moz-cite-prefix">Den 02.05.2025 21:42, skrev Andrew
Randrianasulu:<br>
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<div dir="ltr" class="gmail_attr">пт, 2 мая 2025 г., 22:37
Terje J. Hanssen <<a
href="mailto:terjejhanssen@gmail.com"
moz-do-not-send="true" class="moz-txt-link-freetext">terjejhanssen@gmail.com</a>>:<br>
</div>
<blockquote class="gmail_quote"
style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">
<div> <a
href="https://www.mail-archive.com/cin@lists.cinelerra-gg.org/msg05748.html"
target="_blank" rel="noreferrer"
moz-do-not-send="true" class="moz-txt-link-freetext">https://www.mail-archive.com/cin@lists.cinelerra-gg.org/msg05748.html</a><br>
<br>
I contine this new thread with an short extract from
the long growing<br>
[Cin] ms2130 HDMI-USB3 UHD capture card - not quite as
expected?<br>
<br>
But shouldn't a 422 and not a 420 output format be
created?<br>
<br>
<blockquote>>> it seems in some cases ffmpeg not
geared towards preserving most information, just
picks up most commonly defined/first pixel format. <br>
>> Try mpeg2video as output codec, and/or
specify pixel format (pix_fmt) more explicitly
before output's filename?<br>
<br>
>>> Could you possibly examplify the
latter?<br>
<br>
>>>> I think I just theorized ffmpeg may
try to get some info from alsa device file directly,
as it tries with /dev/video. But I never
>>>> tried this way, so I can be totally
wrong!<br>
</blockquote>
-------------------------------<br>
<br>
Instead of 50i (pal interlaced fields), I try 50 fps
(progressive) that at least is a pal frequence.<br>
<br>
And yes, it seems from the output that ffmpeg uses
mpeg1video as default output codec.<br>
<br>
Furter I try to combine the current line<br>
<blockquote>ffmpeg -hide_banner -f v4l2 -input_format
yuyv422 -video_size 720x576 -framerate 25 -t 20 -i
/dev/video2 out-720x576_ms2130.mpeg<br>
</blockquote>
<br>
with and utilize the syntax developed 2021 for
"Blu-ray compliant MPEG-2 SD video with LPCM audio"<br>
<blockquote>ffmpeg -i dv28.dv -c:v mpeg2video -refs 1
-bf 2 -b:v 25M -maxrate 25M -minrate 25M -bufsize
45M -muxrate 45M -dc 10 -c:a pcm_s16be -f vob
dv28.mpg <br>
</blockquote>
and for the current ongoing "DVD compliant MPEG-2
Video and PCM Audio"<br>
<blockquote>ffmpeg -hide_banner -i dv01.dv -c:v
mpeg2video -refs 1 -bf 2 -b:v 8M -maxrate 8M
-minrate 8M -bufsize 20M -muxrate 11M -dc 10 -c:a
pcm_dvd -f vob -flags +ilme+ildct dv01.mpg<br>
</blockquote>
to first<br>
<blockquote>ffmpeg -hide_banner -f v4l2 -input_format
yuyv422 -video_size 720x576 -framerate 50 -c:v
mpeg2video -refs 1 -bf 2 -b:v 8M -maxrate 8M
-minrate 8M -bufsize 20M -muxrate 11M -dc 10 -c:a
pcm_dvd -f vob -t 20 -i /dev/video2
720x576_50p_ms2130.mpg <br>
Option b:v (video bitrate (please use -b:v)) cannot
be applied to input url /dev/video2 -- you are
trying to apply an input option to an output file or
vice versa. Move this option before the file it
belongs to.<br>
Error parsing options for input file /dev/video2.<br>
Error opening input files: Invalid argument<br>
</blockquote>
<br>
and next revised with no output. That is I need help
to debug the syntax error: <br>
<blockquote>ffmpeg -hide_banner -f v4l2 -input_format
yuyv422 -video_size 720x576 -framerate 50 -i
/dev/video2 -c:v mpeg2video -refs 1 -bf 2 -b:v 8M
-maxrate 8M -minrate 8M -bufsize 20M -muxrate 11M
-dc 10 -c:a pcm_dvd -f vob -t 20
720x576_50p_ms2130.mpg<br>
[video4linux2,v4l2 @ 0x55db770ef9c0] Dequeued v4l2
buffer contains corrupted data (0 bytes).<br>
Input #0, video4linux2,v4l2, from '/dev/video2':<br>
Duration: N/A, start: 0.000000, bitrate: 331776
kb/s<br>
Stream #0:0: Video: rawvideo (YUY2 / 0x32595559),
yuyv422, 720x576, 331776 kb/s, 50 fps, 50 tbr, 1000k
tbn<br>
Stream mapping:<br>
Stream #0:0 -> #0:0 (rawvideo (native) ->
mpeg2video (native))<br>
Press [q] to stop, [?] for help<br>
[video4linux2,v4l2 @ 0x55db770ef9c0] Dequeued v4l2
buffer contains corrupted data (0 bytes).<br>
Last message repeated 30 times<br>
[mpeg2video @ 0x55db77114f00] Warning vbv_delay will
be set to 0xFFFF (=VBR) as the specified vbv buffer
is too large for the given bitrate!<br>
Output #0, vob, to '720x576_50p_ms2130.mpg':<br>
Metadata:<br>
encoder : Lavf59.27.100<br>
Stream #0:0: Video: mpeg2video (4:2:2),
yuv422p(tv, progressive), 720x576, q=2-31, 8000
kb/s, 50 fps, 90k tbn<br>
Metadata:<br>
encoder : Lavc59.37.100 mpeg2video<br>
Side data:<br>
cpb: bitrate max/min/avg:
8000000/8000000/8000000 buffer size: 20000000
vbv_delay: N/A<br>
frame= 0 fps=0.0 q=0.0 Lsize= 0kB
time=00:00:00.00 bitrate=N/A speed= 0x <br>
video:0kB audio:0kB subtitle:0kB other streams:0kB
global headers:0kB muxing overhead: unknown<br>
Output file is empty, nothing was encoded (check -ss
/ -t / -frames parameters if used)<br>
</blockquote>
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<div dir="auto"><br>
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<div dir="auto">well, I think framerate still 25 for 50i
stream ....</div>
<div dir="auto"><br>
</div>
<div dir="auto">can you re-check last line with framerate
parameter removed or changed back to 25?</div>
<div dir="auto"><br>
</div>
</div>
</blockquote>
<br>
Ok, as this old post by my mistake already has been forwarded to
the list and replied, I will follow it up later today, but need to
rig rig up my camcorder and devices <br>
</blockquote>
<br>
Finally ready, I had to recall a lot since 2023.<br>
<br>
ls /dev/video*<br>
/dev/video0 /dev/video1 /dev/video2 /dev/video3<br>
<br>
<br>
for i in /dev/video*; do echo "$i"; udevadm info --query=all
--attribute-walk --name=$i | grep -E "name"; done<br>
/dev/video0<br>
ATTR{name}=="USB3.0 UHD: USB3.0 UHD"<br>
/dev/video1<br>
ATTR{name}=="USB3.0 UHD: USB3.0 UHD"<br>
/dev/video2<br>
ATTR{name}=="USB 2.0 Camera: HD 720P Webcam"<br>
/dev/video3<br>
ATTR{name}=="USB 2.0 Camera: HD 720P Webcam"<br>
<br>
<br>
v4l2-ctl --list-devices<br>
USB 2.0 Camera: HD 720P Webcam (usb-0000:00:14.0-11.2):<br>
/dev/video2<br>
/dev/video3<br>
/dev/media1<br>
<br>
USB3.0 UHD: USB3.0 UHD (usb-0000:00:14.0-3):<br>
/dev/video0<br>
/dev/video1<br>
/dev/media0<br>
<br>
As seen the HDMI-USB3 capture card + the S-Video/HDMI converter
(with the analog S-video camcorder) is now on /dev/video0<br>
while the USB2 webcam is on /dev/video2<br>
<br>
ffplay can playback the S-video camcorder's imaging stream<br>
<br>
<blockquote>Default without framerate specified:<br>
<br>
ffplay -hide_banner -f video4linux2 /dev/video0<br>
[video4linux2,v4l2 @ 0x7fe3c0000c80] Dequeued v4l2 buffer contains
corrupted data (0 bytes).<br>
Input #0, video4linux2,v4l2, from '/dev/video0':<br>
Duration: N/A, start: 0.000000, bitrate: 398131 kb/s<br>
Stream #0:0: Video: rawvideo (YUY2 / 0x32595559), yuyv422,
720x576, 398131 kb/s, 60 fps, 60 tbr, 1000k tbn<br>
[video4linux2,v4l2 @ 0x7fe3c0000c80] Dequeued v4l2 buffer contains
corrupted data (0 bytes).<br>
Last message repeated 30 times<br>
^Cterje@localhost:~> d= 2 aq= 0KB vq= 0KB sq= 0B <br>
<br>
With 25 fps specified:<br>
<br>
ffplay -hide_banner -f video4linux2 -framerate 25 /dev/video0<br>
[video4linux2,v4l2 @ 0x7f7fa8000c80] The driver changed the time
per frame from 1/25 to 1/30<br>
[video4linux2,v4l2 @ 0x7f7fa8000c80] Dequeued v4l2 buffer contains
corrupted data (0 bytes).<br>
Input #0, video4linux2,v4l2, from '/dev/video0':<br>
Duration: N/A, start: 0.000000, bitrate: 199065 kb/s<br>
Stream #0:0: Video: rawvideo (YUY2 / 0x32595559), yuyv422,
720x576, 199065 kb/s, 30 fps, 30 tbr, 1000k tbn<br>
[video4linux2,v4l2 @ 0x7f7fa8000c80] Dequeued v4l2 buffer contains
corrupted data (0 bytes).<br>
Last message repeated 30 times<br>
^Cterje@localhost:~> d= 0 aq= 0KB vq= 0KB sq= 0B <br>
<br>
With 30 fps specified:<br>
<br>
ffplay -hide_banner -f video4linux2 -framerate 30 /dev/video0<br>
[video4linux2,v4l2 @ 0x7f3878000c80] Dequeued v4l2 buffer contains
corrupted data (0 bytes).<br>
Input #0, video4linux2,v4l2, from '/dev/video0':<br>
Duration: N/A, start: 0.000000, bitrate: 199065 kb/s<br>
Stream #0:0: Video: rawvideo (YUY2 / 0x32595559), yuyv422,
720x576, 199065 kb/s, 30 fps, 30 tbr, 1000k tbn<br>
[video4linux2,v4l2 @ 0x7f3878000c80] Dequeued v4l2 buffer contains
corrupted data (0 bytes).<br>
Last message repeated 30 times<br>
</blockquote>
-----------------<br>
<br>
But empty output file with ffmpeg:<br>
<br>
With 25 fps specified<br>
<blockquote>ffmpeg -hide_banner -f v4l2 -input_format yuyv422
-video_size 720x576 -framerate 25 -i /dev/video0 -c:v mpeg2video
-refs 1 -bf 2 -b:v 8M -maxrate 8M -minrate 8M -bufsize 20M
-muxrate 11M -dc 10 -c:a pcm_dvd -f vob -t 20
720x576_25fps_ms2130.mpg<br>
[video4linux2,v4l2 @ 0x560fe5926740] The driver changed the time
per frame from 1/25 to 1/30<br>
[video4linux2,v4l2 @ 0x560fe5926740] Dequeued v4l2 buffer contains
corrupted data (0 bytes).<br>
Input #0, video4linux2,v4l2, from '/dev/video0':<br>
Duration: N/A, start: 0.000000, bitrate: 199065 kb/s<br>
Stream #0:0: Video: rawvideo (YUY2 / 0x32595559), yuyv422,
720x576, 199065 kb/s, 30 fps, 30 tbr, 1000k tbn<br>
Stream mapping:<br>
Stream #0:0 -> #0:0 (rawvideo (native) -> mpeg2video
(native))<br>
Press [q] to stop, [?] for help<br>
[video4linux2,v4l2 @ 0x560fe5926740] Dequeued v4l2 buffer contains
corrupted data (0 bytes).<br>
Last message repeated 30 times<br>
[mpeg2video @ 0x560fe5927140] Warning vbv_delay will be set to
0xFFFF (=VBR) as the specified vbv buffer is too large for the
given bitrate!<br>
Output #0, vob, to '720x576_25fps_ms2130.mpg':<br>
Metadata:<br>
encoder : Lavf61.7.100<br>
Stream #0:0: Video: mpeg2video (4:2:2), yuv422p(tv,
progressive), 720x576, q=2-31, 8000 kb/s, 30 fps, 90k tbn<br>
Metadata:<br>
encoder : Lavc61.19.101 mpeg2video<br>
Side data:<br>
cpb: bitrate max/min/avg: 8000000/8000000/8000000 buffer
size: 20000000 vbv_delay: N/A<br>
[out#0/vob @ 0x560fe5928d00] video:0KiB audio:0KiB subtitle:0KiB
other streams:0KiB global headers:0KiB muxing overhead: unknown<br>
[out#0/vob @ 0x560fe5928d00] Output file is empty, nothing was
encoded(check -ss / -t / -frames parameters if used)<br>
frame= 0 fps=0.0 q=0.0 Lsize= 0KiB time=N/A bitrate=N/A
speed=N/A <br>
</blockquote>
<br>
Without framerate specified:<br>
<blockquote>ffmpeg -hide_banner -f v4l2 -input_format yuyv422
-video_size 720x576 -i /dev/video0 -c:v mpeg2video -refs 1 -bf 2
-b:v 8M -maxrate 8M -minrate 8M -bufsize 20M -muxrate 11M -dc 10
-c:a pcm_dvd -f vob -t 20 720x576_ms2130.mpg<br>
[video4linux2,v4l2 @ 0x55e707fd8740] Dequeued v4l2 buffer contains
corrupted data (0 bytes).<br>
Input #0, video4linux2,v4l2, from '/dev/video0':<br>
Duration: N/A, start: 0.000000, bitrate: 398131 kb/s<br>
Stream #0:0: Video: rawvideo (YUY2 / 0x32595559), yuyv422,
720x576, 398131 kb/s, 60 fps, 60 tbr, 1000k tbn<br>
Stream mapping:<br>
Stream #0:0 -> #0:0 (rawvideo (native) -> mpeg2video
(native))<br>
Press [q] to stop, [?] for help<br>
[video4linux2,v4l2 @ 0x55e707fd8740] Dequeued v4l2 buffer contains
corrupted data (0 bytes).<br>
Last message repeated 30 times<br>
[mpeg2video @ 0x55e707fd9140] Warning vbv_delay will be set to
0xFFFF (=VBR) as the specified vbv buffer is too large for the
given bitrate!<br>
Output #0, vob, to '720x576_ms2130.mpg':<br>
Metadata:<br>
encoder : Lavf61.7.100<br>
Stream #0:0: Video: mpeg2video (4:2:2), yuv422p(tv,
progressive), 720x576, q=2-31, 8000 kb/s, 60 fps, 90k tbn<br>
Metadata:<br>
encoder : Lavc61.19.101 mpeg2video<br>
Side data:<br>
cpb: bitrate max/min/avg: 8000000/8000000/8000000 buffer
size: 20000000 vbv_delay: N/A<br>
[out#0/vob @ 0x55e707fdacc0] video:0KiB audio:0KiB subtitle:0KiB
other streams:0KiB global headers:0KiB muxing overhead: unknown<br>
[out#0/vob @ 0x55e707fdacc0] Output file is empty, nothing was
encoded(check -ss / -t / -frames parameters if used)<br>
frame= 0 fps=0.0 q=0.0 Lsize= 0KiB time=N/A bitrate=N/A
speed=N/A <br>
</blockquote>
--------------<br>
<br>
On the other hand, capturing with the USB webcam creates output file<br>
<br>
Here with 50 fps specified<br>
<blockquote>ffmpeg -hide_banner -f v4l2 -input_format yuyv422
-video_size 720x576 -framerate 50 -i /dev/video2 -c:v mpeg2video
-refs 1 -bf 2 -b:v 8M -maxrate 8M -minrate 8M -bufsize 20M
-muxrate 11M -dc 10 -c:a pcm_dvd -f vob -t 20
720x576_50p_ms2130.mpg<br>
[video4linux2,v4l2 @ 0x56418fd52740] The V4L2 driver changed the
video from 720x576 to 800x600<br>
[video4linux2,v4l2 @ 0x56418fd52740] The driver changed the time
per frame from 1/50 to 1/20<br>
Input #0, video4linux2,v4l2, from '/dev/video2':<br>
Duration: N/A, start: 1969.283514, bitrate: 153600 kb/s<br>
Stream #0:0: Video: rawvideo (YUY2 / 0x32595559), yuyv422,
800x600, 153600 kb/s, 20 fps, 20 tbr, 1000k tbn<br>
Stream mapping:<br>
Stream #0:0 -> #0:0 (rawvideo (native) -> mpeg2video
(native))<br>
Press [q] to stop, [?] for help<br>
[mpeg2video @ 0x56418fd53200] Warning vbv_delay will be set to
0xFFFF (=VBR) as the specified vbv buffer is too large for the
given bitrate!<br>
Output #0, vob, to '720x576_50p_ms2130.mpg':<br>
Metadata:<br>
encoder : Lavf61.7.100<br>
Stream #0:0: Video: mpeg2video (4:2:2), yuv422p(tv,
progressive), 800x600, q=2-31, 8000 kb/s, 20 fps, 90k tbn<br>
Metadata:<br>
encoder : Lavc61.19.101 mpeg2video<br>
Side data:<br>
cpb: bitrate max/min/avg: 8000000/8000000/8000000 buffer
size: 20000000 vbv_delay: N/A<br>
[out#0/vob @ 0x56418fd54e00] video:13281KiB audio:0KiB
subtitle:0KiB other streams:0KiB global headers:0KiB muxing
overhead: 1.230734%<br>
frame= 284 fps= 22 q=2.0 Lsize= 13444KiB time=00:00:14.15
bitrate=7783.3kbits/s dup=97 drop=0 speed=1.08x <br>
Exiting normally, received signal 2.<br>
<br>
</blockquote>
<blockquote>ffprobe -hide_banner 720x576_50p_ms2130.mpg<br>
Input #0, mpeg, from '720x576_50p_ms2130.mpg':<br>
Duration: 00:00:14.20, start: 0.550000, bitrate: 7755 kb/s<br>
Stream #0:0[0x1e0]: Video: mpeg2video (4:2:2), yuv422p(tv,
progressive), 800x600 [SAR 1:1 DAR 4:3], 20 fps, 20 tbr, 90k tbn<br>
Side data:<br>
cpb: bitrate max/min/avg: 8000000/0/0 buffer size:
20004864 vbv_delay: N/A<br>
<br>
</blockquote>
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