veejay read from pipe

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d.j...@free.fr

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Mar 13, 2016, 7:02:45 AM3/13/16
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Hello freedom pixel front,

I'm read here and there that veejay can read from a pipe.

Using libav (avconv) i redirect a stream (/dev/videox) to a pipe

$ mkfifo /tmp/fifo
$ avconv -f video4linux2 -i /dev/video0 -pix_fmt yuv420p -s 720x576 -f rawvideo /tmp/fifo

If i cat the pipe, $ cat /tmp/fifo , some binary data are printed on stdout ... so i think i'm feeding well the pipe.

How is it possible to read it from veejay ?

Cheers, and more other good data.

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Niels Elburg

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Mar 13, 2016, 7:16:14 AM3/13/16
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Hi,

echo "243:/tmp/fifo;"  |sayVIMS

I: VIMS selector 243    'Open yuv4mpeg (special) file as new input stream'
I:      FORMAT: '%s', where:
I:              Argument 0 is Filename

I think, there is also some option to do this in reloaded, via Stream -> New (?)

See you,


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d.j...@free.fr

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Mar 13, 2016, 7:16:40 AM3/13/16
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Hello bis,

I know you want to ask "why i did'nt directly read the /dev/videox from veejay ???"

Because i'm actually from of a veejay problem decoding the device
(Hauppauge USB Live 2) stream [16bpp YUY2, 4:2:2, packed, YUYV]

re Cheers and other nice data.

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Niels Elburg

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Mar 13, 2016, 7:21:09 AM3/13/16
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There's an update to v4l2, perhaps that will solve your problem ? :)

If not, need to know if device support MMAP capture or READ only, and need output from v4l2-ctl -d /dev/video0 --all

Also, does the video pipe give correct colors ?

Just noticed that the following gives a wrong picture:

$ mkfifo /tmp/stream.yuv
$ mplayer -vo yuv4mpeg /media/hd/avi/Chiffres.avi -loop 999
$ veejay -w 800 -h 600 -A1 -v
$ echo "243:/tmp/stream.yuv;"|sayVIMS

<press F2 in veejay>

See you,

d.j...@free.fr

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Mar 14, 2016, 8:27:23 AM3/14/16
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Hi,

>echo "243:/tmp/fifo;" |sayVIMS
>
>I: VIMS selector 243 'Open yuv4mpeg (special) file as new input stream'
>I: FORMAT: '%s', where:
>I: Argument 0 is Filename
>

I had found that searching the mailing list but was not able to work with it ... now yes !, i had
my video camera inside veejay .... but ... look like i have a problem with "pixel format" yuv something wrong

$ mkfifo /tmp/video.yuv & avconv -f video4linux2 -i /dev/video1 -pix_fmt yuv420p -s 720x576 -f yuv4mpegpipe /tmp/video.yuv & echo "243:/tmp/video.yuv;" |sayVIMS

http://pix.toile-libre.org/upload/original/1457958339.png

is it the same problem you had ????

>I think, there is also some option to do this in reloaded, via Stream -> New (?)
Nop ... "only" /dev/videox and network ... something for the issue tracker (i should be able to fix it)


Driver Info (not using libv4l2):
Driver name : cx231xx
Card type : Hauppauge USB Live 2
Bus info : usb-0000:00:03.3-4
Driver version: 3.19.8
Capabilities : 0x85200011
Video Capture
VBI Capture
Read/Write
Streaming
Extended Pix Format
Device Capabilities
Device Caps : 0x05200001
Video Capture
Read/Write
Streaming
Extended Pix Format
Priority: 2
Video input : 0 (Composite1: ok)
Video Standard = 0x000000ff
PAL-B/B1/G/H/I/D/D1/K
Format Video Capture:
Width/Height : 720/576
Pixel Format : 'YUYV'
Field : Interlaced
Bytes per Line: 1440
Size Image : 829440
Colorspace : Broadcast NTSC/PAL (SMPTE170M/ITU601)
Flags :
Crop Capability Video Capture:
Bounds : Left 0, Top 0, Width 720, Height 576
Default : Left 0, Top 0, Width 720, Height 576
Pixel Aspect: 54/59
Streaming Parameters Video Capture:
Frames per second: 25.000 (25/1)
Read buffers : 2

User Controls

brightness (int) : min=0 max=255 step=1 default=128 value=128 flags=slider
contrast (int) : min=0 max=127 step=1 default=64 value=64 flags=slider
saturation (int) : min=0 max=127 step=1 default=64 value=64 flags=slider
hue (int) : min=-128 max=127 step=1 default=0 value=0 flags=slider
volume (int) : min=0 max=65535 step=655 default=60928 value=60928 flags=slider
balance (int) : min=0 max=65535 step=655 default=32768 value=32768 flags=slider
bass (int) : min=0 max=65535 step=655 default=32768 value=32768 flags=slider
treble (int) : min=0 max=65535 step=655 default=32768 value=32768 flags=slider
mute (bool) : default=0 value=0
brightness (int) : min=0 max=255 step=1 default=128 value=128 flags=slider
contrast (int) : min=0 max=127 step=1 default=64 value=64 flags=slider
saturation (int) : min=0 max=127 step=1 default=64 value=64 flags=slider
hue (int) : min=-128 max=127 step=1 default=0 value=0 flags=slider
volume (int) : min=0 max=65535 step=655 default=60928 value=60928 flags=slider
balance (int) : min=0 max=65535 step=655 default=32768 value=32768 flags=slider
bass (int) : min=0 max=65535 step=655 default=32768 value=32768 flags=slider
treble (int) : min=0 max=65535 step=655 default=32768 value=32768 flags=slider
mute (bool) : default=0 value=0

cheers ... !

d.j...@free.fr

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Mar 14, 2016, 12:59:48 PM3/14/16
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Hipa !!!!

Niels, you did it ... !!!

I'have just builded fresh code : Commits on Mar 13, 2016 and the color yuyuv problem is fixed ...

Niels ... you are so mastering !

Thank's a lot and a lot of thank's.... !

see'ya.
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