<div dir="auto"><div><br><br><div class="gmail_quote"><div dir="ltr" class="gmail_attr">пт, 10 мар. 2023 г., 02:43 Terje J. Hanssen <<a href="mailto:terjejhanssen@gmail.com">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>
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>
</div></blockquote></div></div><div dir="auto"><br></div><div dir="auto">I am afraid you probably need help from ffmpeg-users mail list here .... Last line looks correct, yet not encoding??</div><div dir="auto"><br></div><div dir="auto"><br></div><div dir="auto"><div class="gmail_quote"><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"><div><br>
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</blockquote></div></div></div>