<div>Hi Devs!</div><div><br></div><div>First, I would like to thank you for developing this great tool. It allowed</div><div>me streaming from v4l2 web cam and sound card stream to my rtmp server</div><div>without loosing a/v sync which is not possible with competition like</div>
<div>ffmpeg.</div><div><br></div><div>Now get back to problem I've discovered. I've USB microsoft live cam which</div><div>is capable to stream RAW video and MJPEG video. RAW video is in YUY2. The</div><div>problem is that whan I stream RAW video in YUY2, contrast or gamma or</div>
<div>rounding problem (dont know) are ok. But once I stream in MJPEG, contrast is</div><div>too high and ligh places are too light so it creates white shapes (sorry for</div><div>my english).</div><div><br></div><div>Here is command line for YUY2 video which is OK</div>
<div><br></div><div>gst-launch -v -m v4l2src ! queue !</div><div>video/x-raw-yuv,format='(fourcc)'YUY2,width=640,height=360,framerate=30/1 !</div><div>ffmpegcolorspace ! queue ! videorate ! 'video/x-raw-yuv,framerate=30/1' !</div>
<div>hqdn3d ! x264enc</div><div><br></div><div>I've checked with v4l2-ctl that in the first case, pixel format is</div><div> Pixel Format : 'YUYV'</div><div> Colorspace : SRGB</div><div><br></div>
<div><br></div><div>Here is command line for MJPEG which has bad contrast</div><div><br></div><div>gst-launch -v -m v4l2src ! image/jpeg,width=640,height=360,framerate=30/1 !</div><div>queue ! ffdec_mjpeg ! ffmpegcolorspace ! queue ! videorate !</div>
<div>'video/x-raw-yuv,framerate=30/1' ! x264enc</div><div><br></div><div>v4l2-ctl -V</div><div> Pixel Format : 'MJPG'</div><div> Colorspace : SRGB</div><div><br></div><div><br></div><div>
Streaming in MJPEG with ffmpeg looks good (contrast is ok)</div><div><br></div><div>ffmpeg -f alsa -i plughw:0 -f video4linux2 -s 640x360 -r 30 -i /dev/video0</div><div>-vcodec libx264 -threads 0 -vpre slow -b 500000 -strict experimental</div>
<div> -acodec libfaac -ar 44100 -f flv rtmp://a.b.c.d/flvplayback/festr</div><div>v4l2-ctl -V</div><div> Pixel Format : 'MJPG'</div><div> Colorspace : SRGB</div><div><br></div><div><br></div><div>
Anyone know if this is known issue or bug or misconfiguration? I've tried</div><div>forcing v4l2 src plugin to video/x-raw-yuv,format='(fourcc)'YV12 format</div><div>which sets my camera to MJPEG and the result is same, high contrast.</div>
<div><br></div><div><br></div><div>Thank you if you read the whole message and for possible hints.</div><div>Regards</div><div>Martin Vit</div>