curtis newton's profile - activity

Hello,

is there a way to add cross-checking = true parameter

using DescriptorMatcher::create ?

reagards

actually, I find between 60 and 150 matches, I'll try to add some angle to it

nop, it is hard plastic. besides, even if the image content does not change and the camera stay put, I get the same issue, even if the features matches are filtered to be consistents

Hello,

I built a stereo camera rig, and I wanted to do triangulation (find X(3d) from xL and xR)

but althought I have good features matches, the fundamental matrix gets sometimes right, sometimes out of whack, no matter what algo I use(ransac, 7pts, 8pts, lmds) if I check xL.t() * F * xR, I get sometimes results close to 0 (barely) sometimes way more than 1

so is it possible that becos of my two cameras are parallel ? should I turn them to some focal point, I though about making it variable, but I would have to recalibrate the rig all the time

the other solution, is to use only one camera and to triangulate from consecutive images (robot moving in 3D space)

any advice is welcome

I can provide the code if needed, but I am pretty sure it is not the issue

ok I missed that reading the doc thx

hello,

I am trying to get pixels values from an image

if I use this line : Vec3b col = imageSource.at<vec3bf>(kp.y, kp.x); I get regular color bytes values

If I use shis one : Vec3f col = imageSource.at<vec3f>(kp.y, kp.x); rgb values are like 1.1234e36 or something

so I would expect values from 0.0 to 1.0 or 0.0 to 255.0 but e+36 ??

I'll go for the bytes version, but the float seemed neat as they are intended for opengl colors floats

@StevenPuttemans thx for letting me hanging there, hopefully I created another post besides I need highgui cos of imread and imwrite, so I am screwed

anyone ????

i tired but opencv only detects one chess board per image

hello,

as I cant compile opencv on ubuntu 14.04/arm platform (highgui has errors)

(my previous unresolved thread here http://answers.opencv.org/question/40348/error-compiling-245-on-ubuntu/)

I wanted to know if I could add a compile flag not to use highgui

I use my own anyway

thanks

how can you get m & n for matches ? are these key points ? I use c++ and there is no distance variable in keypoints, only in matches

great link, but how can I detect multiple chessboard on one image ? didn't even know one could do that findChessboardCorners only detects one chessboard..

any idea ?

cmake -D CMAKE_BUILD_TYPE=RELEASE -D CMAKE_INSTALL_PREFIX=/usr/local -D BUILD_EXAMPLES=ON -D WITH_JPEG=ON -D WITH_OPENGL=ON -D WITH_QT=OFF ..

odroid@odroid:~$ uname -a Linux odroid 3.4.75 #1 SMP PREEMPT Thu Jan 2 22:10:03 CST 2014 armv7l armv7l armv7l GNU/Linux

it is an ODROID box, cpu is an arm7/arm15

odroid@odroid:~/WORK/opencv/release$ lsb_release -a No LSB modules are available. Distributor ID: Ubuntu Description: Ubuntu 14.04.1 LTS Release: 14.04 Codename: trusty odroid@odroid:~/WORK/opencv/release$

you "sound" like if i was making this up, lol

[ 9%] Building CXX object modules/highgui/CMakeFiles/opencv_highgui.dir/src/bitstrm.cpp.o Linking CXX shared library ../../lib/libopencv_highgui.so /usr/bin/ld: /usr/local/lib/libavcodec.a(avpacket.o): relocation R_ARM_MOVW_ABS_NC against `av_destruct_packet' can not be used when making a shared object; recompile with -fPIC /usr/local/lib/libavcodec.a: error adding symbols: Bad value collect2: error: ld returned 1 exit status make[2]: * [lib/libopencv_highgui.so.2.4.9] Error 1 make[1]: [modules/highgui/CMakeFiles/opencv_highgui.dir/all] Error 2 make: ** [all] Error 2

I just grabbed the latest 2.4.9 version on ubuntu 14.04 and got exactly the same error :-) so I dont know maybe I am cursed

Htc ? yes I use opencv's code, and in fact it works depending on some images set it does not work with too many images, or images that are to much alike, but it is a complete random blind guess if it is going to work or not, a non working set becomes working set by just removing a few images but I can't really figure out the golden rule how to make it work, it took me two days tweaking the image sets to have a decent camera matrix with the result like the one above

why? guess (i give you an indice : f@#king ubuntu) I already had these kind of errors( f@#king ARM cpu's) and many other issues trying to compile previous versions of opencv. it takes days and tons of patience to achive that (if possible)

yes I thought about the lens having different focales but i use web cams so no auto focus :-) I dont understand why calibration is so random, I get different results with the same set of images the best result i can get is a realy smaller image with the corners completely out of whack so for a 320x200 image i get something like 160x100 working region what a waste.. i thought that croping/aligning one image regarding the other would ask less effort and do the trick but i dont know for sure, i need to calc depth/disparity

yes i did..

anyone could answer this ?

i got exactly the same issue

result change all the time, it works nice with opencv example images but for real life tests, it is super hard to have correct matrix setup

hello,

i try to do stereo calibration but i get either black images or weird results (distoreted rotated images)

I use stereo_calibration.cpp from opencv 2.4.5

so i got a few questions

• why do I have different results with the same set of images ?
• is there a minimum distance between the two cameras?
• why calibration only use 1 cpu (I got 4 cpus, it could use at leas 2 of them)
• how could i debug/interpret the resulting matrix ?

please help me thanks

hello ,

trying to compile 2.4.5 from GIT, on Ubuntu

gives this

[code] /usr/bin/ld: /usr/local/lib/libavcodec.a(avpacket.o): relocation R_ARM_MOVW_ABS_NC against `av_destruct_packet' can not be used when making a shared object; recompile with -fPIC /usr/local/lib/libavcodec.a: error adding symbols: Bad value collect2: error: ld returned 1 exit status make[2]: * [lib/libopencv_highgui.so.2.4.5] Error 1 make[1]: [modules/highgui/CMakeFiles/opencv_highgui.dir/all] Error 2 make: ** [all] Error 2 [/code]

so i downloaded x264 package and compiled with -pic and -shared option but still get the same issue

please help me out

thanks

ok, what are the alternative to SURF and SIFT if any ?

Hello,

i cant use SIFT on Ubuntu / opencv 2.4.5

Netbeans does not find cv::initModule_nonfree();

and there is no opencv2/nonfree directory

i installed all opencv packages

please help me out

thanks

Hello,

can anyone tell me what version of opencv is compatible (buildable/linkable) with qt4

so far i compile opencv 248 with qt5 but i need qt4(ubuntu leaves me no choices on arm processor) when i compile 248 with qt4 i get nasty errors about opengl redefinition of GLFloats i also tried with 2.4.0 and 2.3.1, still got the same issue seems like it was never meant to compile on ubuntu with qt4

thx

Hello, as i try to compile an opencv code originaly from windows, i get

fatal error: opencv2/gpu/gpu.hpp: No such file or directory

and i cant find that file nowhere in the opencv directory

i got the repository like this

git clone https://github.com/Itseez/opencv.git

so has this been removed ? i cant find anyone having the same issu on the web

plz help me

[i downloaded the stable 2.4.8 and noticed it was there but in the non free section, so is there going to be some alternative in the git repository ?]

yep after copying everything in on rep it works

anyone ? i saw other people having the same issue on stackoverflow seems like it is an eclipse bug in some cases (like having workspace on c drive and refering to other project on another drive