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AndrewFromMelbourne / dmxwebcam

A webcam (v4l2) viewer for the Raspberry Pi console.
MIT License
21 stars 7 forks source link

HDMI capture device #6

Open skinkie opened 5 years ago

skinkie commented 5 years ago

At this moment I am testinga HDMI capture device. (I expect that device is actually a HDMI to composite to capture device.) Using this device in mplayer on an ordinary PC I receive colours.

Selected device: usbtv
 Capabilities:  video capture  read/write  streaming
 supported norms: 0 = NTSC; 1 = NTSC-M; 2 = NTSC-M-JP; 3 = NTSC-M-KR; 4 = NTSC-443; 5 = PAL; 6 = PAL-BG; 7 = PAL-H; 8 = PAL-I; 9 = PAL-DK; 10 = PAL-M; 11 = PAL-60;
 inputs: 0 = Composite; 1 = S-Video;
 Current input: 0
 Current format: YUYV

[swscaler @ 0x55d43a6fdbe0] bicubic scaler, from yuyv422 to bgra using MMXEXT
VO: [x11] 720x576 => 720x576 BGRA 
Selected video codec: [rawyuy2] vfm: raw (RAW YUY2)

When using this device with dmxwebcam, I instead see a black and white image with blue and yellow vertical lines, additionally there is heavy overscan, which does not appear using mplayer.

./dmxwebcam --fullscreen --display 1 --width 720 --height 576 --fps 25
dmxwebcam[2048]:info:video dimension 720x576 -> 720x480
dmxwebcam[2048]:error:unable to set requested fps (25)

So I think there are two individual problems: the correct source colourspace (and its potential conversion) the other capture usb stick does appear in colour. And the automatic resolution reduction.

skinkie commented 5 years ago

Colourspace solution

v4l2-ctl -d /dev/video0 -s pal-B