Re: [PD] openCV face detection performance Was: make me
ola, i dunno, is the source of the sofware coming with your cam available? second, you don't need to convert to grayscale, it's already made internally saludos, sevy Max wrote: While I was checking out a Canon EOS 5D automatic face detection and focus, I wondered why this camera can do so effortless and the OpenCV on a Mac 8 core machine uses one Processor with 250% for that. When changing to greyscale colorspace and reducing the resolution to a quarter of PAL one get under 100% but it still still seems like a lot. Any Ideas why that could be? m. Am 19.08.2010 um 13:34 schrieb ydego...@gmail.com: ola, basically what is missing from opencv is an 6 DOF Head Tracking. do you have an idea on which algorithm it is based? i googled a bit but couldn't find really valuable information on this... saludos, sevy ___ Pd-list@iem.at mailing list UNSUBSCRIBE and account-management - http://lists.puredata.info/listinfo/pd-list ___ Pd-list@iem.at mailing list UNSUBSCRIBE and account-management - http://lists.puredata.info/listinfo/pd-list
[PD] openCV face detection performance Was: make me
While I was checking out a Canon EOS 5D automatic face detection and focus, I wondered why this camera can do so effortless and the OpenCV on a Mac 8 core machine uses one Processor with 250% for that. When changing to greyscale colorspace and reducing the resolution to a quarter of PAL one get under 100% but it still still seems like a lot. Any Ideas why that could be? m. Am 19.08.2010 um 13:34 schrieb ydego...@gmail.com: ola, basically what is missing from opencv is an 6 DOF Head Tracking. do you have an idea on which algorithm it is based? i googled a bit but couldn't find really valuable information on this... saludos, sevy ___ Pd-list@iem.at mailing list UNSUBSCRIBE and account-management - http://lists.puredata.info/listinfo/pd-list ___ Pd-list@iem.at mailing list UNSUBSCRIBE and account-management - http://lists.puredata.info/listinfo/pd-list
Re: [PD] openCV face detection performance Was: make me
On Thu, 19 Aug 2010, Max wrote: While I was checking out a Canon EOS 5D automatic face detection and focus, I wondered why this camera can do so effortless and the OpenCV on a Mac 8 core machine uses one Processor with 250% for that. When changing to greyscale colorspace and reducing the resolution to a quarter of PAL one get under 100% but it still still seems like a lot. Any Ideas why that could be? There are several reasons, one of which being that specialised processors can still be much faster than general processors (just look at what video cards can do...) but it's also very possible that they downscale the image by a factor of 2*2 (4 times faster) or 4*4 (16 times faster) before starting to apply the face detection. Note also that converting from GEM's YUV to RGB upscales the U and V channel by a factor of 2 horizontally (no vertical scaling), which means that the RGB data is a bit redundant. That's the 422 mode. For cameras in YUV 420 mode, there's also vertical scaling, therefore, in my camera code, I have added an option to convert directly from YUV420 to a twice narrower, twice shorter RGB picture, for the case where the chroma resolution is absolutely essential. It reduces a lot of waste. _ _ __ ___ _ _ _ ... | Mathieu Bouchard, Montréal, Québec. téléphone: +1.514.383.3801___ Pd-list@iem.at mailing list UNSUBSCRIBE and account-management - http://lists.puredata.info/listinfo/pd-list
