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codec type or id mismatches when using usb_cam

asked 2012-11-20 08:32:38 -0500

dinamex gravatar image

updated 2014-01-28 17:14:19 -0500

ngrennan gravatar image

Hi all,

I would like to use the usb_cam package to integrate my logitech c920 into my project. Unfortunately, I get the following output when I use mjeg as pixel format:

[swscaler @ 0x4453c7a0] No accelerated colorspace conversion found from yuv422p to rgb24.

Due to the high resolution pictures is this compression necessary, otherwise my system would be to slow. I have a lack of 3-4 seconds with yuyv as pixel format.

I followed this guide to reinstall ffmpeg from source but it didn't change anything... I would very much appreciate any ideas to solve this issue. Thanks


I found this post where they mention that the 6.2 Version should work. I installed it but the error message is now:

[mjpeg @ 0x4461b040]codec type or id mismatches
I could find a decoderCould not open MJPEG Decoder
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I'm afraid I have had this problem in the past and it has nothing to do with ROS. Rather, it is a ffmpeg issue, as you found out. So either you figure out how to get ffmpeg work with it or you'll have to change webcam.

georgebrindeiro gravatar image georgebrindeiro  ( 2012-12-12 09:13:57 -0500 )edit

that what I don't know... I looked up the code under sensor_message/image_encoding.cpp which just offers me rgb16 and not rgb24 how can I change that?

dinamex gravatar image dinamex  ( 2012-12-12 10:02:59 -0500 )edit

@georgebrindeiro Do you know a HD Webcam which supports some compression?

dinamex gravatar image dinamex  ( 2012-12-13 11:15:24 -0500 )edit

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answered 2012-12-14 05:57:35 -0500

I don't know any HD Webcams which support some compression and work well with ffmpeg, but maybe you will find the information you need in the OpenCV Camera Compatibility lists.

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Asked: 2012-11-20 08:32:38 -0500

Seen: 1,595 times

Last updated: Dec 14 '12