VideoCapture set properties ? (Bug #948)

Added by Pei JIA almost 14 years ago. Updated over 12 years ago.

Status:Cancelled Start date:
Priority:High Due date:
Assignee:Vadim Pisarevsky % Done:

0%
Category:highgui-camera
Target version:-
Affected version: Operating System:
Difficulty: HW Platform:
Pull request:

Description

Hi, all:

My VideoCapture won't load specified properties as expected. I tried the following code. However, the captured images are still of default size 640*480, instead of specified 320*240. Can anybody help?

1VideoCapture capture;
2capture.set(CV_CAP_PROP_FRAME_WIDTH,320);
3capture.set(CV_CAP_PROP_FRAME_HEIGHT,240);

Thank you very much.
Best Regards
JIA

camshiftdemo.cpp (6.5 kB) Pei JIA, 2011-03-19 07:08 pm

Related issues

duplicated by Bug #1573: cvSetCaptureProperty has been broken since opencv1.1 Cancelled

Associated revisions

Revision 087db294
Added by Roman Donchenko almost 12 years ago

Merge pull request #948 from jet47:cuda-5.5-support

Revision 3bfc6974
Added by Roman Donchenko over 11 years ago

Merge remote-tracking branch 'origin/2.4' into merge-2.4

Merged pull requests:
#890 from caorong:patch-1
#893 from jet47:gpu-arm-fixes
#933 from pengx17:2.4_macfix_cont
#935 from pengx17:2.4_filter2d_fix
#936 from bitwangyaoyao:2.4_perf
#937 from bitwangyaoyao:2.4_fixPyrLK
#938 from pengx17:2.4_surf_sample
#939 from pengx17:2.4_getDevice
#940 from SpecLad:autolock
#941 from apavlenko:signed_char
#946 from bitwangyaoyao:2.4_samples2
#947 from jet47:fix-gpu-arm-build
#948 from jet47:cuda-5.5-support
#952 from SpecLad:jepg
#953 from jet47:fix-bug-3069
#955 from SpecLad:symlink
#957 from pengx17:2.4_fix_corner_detector
#959 from SpecLad:qt4-build
#960 from SpecLad:extra-modules

Conflicts:
modules/core/include/opencv2/core/core.hpp
modules/gpu/CMakeLists.txt
modules/gpu/include/opencv2/gpu/device/vec_math.hpp
modules/gpu/perf/perf_video.cpp
modules/gpuimgproc/src/cuda/hough.cu
modules/ocl/include/opencv2/ocl/ocl.hpp
modules/ocl/src/pyrlk.cpp
samples/gpu/driver_api_multi.cpp
samples/gpu/driver_api_stereo_multi.cpp
samples/ocl/surf_matcher.cpp

History

#1
Updated by Alexander Shishkov about 13 years ago

I tried it on Windows/Linux, but it works fine.

1VideoCapture cap;
2cap.open(camNum);
3cap.set(CV_CAP_PROP_FRAME_WIDTH, 1024);
4cap.set(CV_CAP_PROP_FRAME_HEIGHT, 768);

or

 1CvCapture* capture = cvCreateCameraCapture(0);
 2cvSetCaptureProperty(capture, CV_CAP_PROP_FRAME_WIDTH, 320);
 3cvSetCaptureProperty(capture, CV_CAP_PROP_FRAME_HEIGHT, 240);
 4while(true)
 5{
 6IplImage* videoFrame = cvQueryFrame(capture);
 7cvShowImage("wind", videoFrame);
 8cvWaitKey(1);
 9}

You should call set(...) functions after initialization VideoCapture object:

1VideoCapture cap;
2cap.open(camNum);
3cap.set(CV_CAP_PROP_FRAME_WIDTH, 1024);
4cap.set(CV_CAP_PROP_FRAME_HEIGHT, 768);

- correct

1VideoCapture cap;
2cap.set(CV_CAP_PROP_FRAME_WIDTH, 1024);
3cap.set(CV_CAP_PROP_FRAME_HEIGHT, 768);
4cap.open(camNum);

- incorrect
  • Status changed from Open to Done
  • (deleted custom field) set to invalid

#2
Updated by Andrey Kamaev about 13 years ago

  • Status changed from Done to Cancelled
  • Description changed from Hi, all: My [[VideoCapture]] won't load specified properties as expecte... to Hi, all: My VideoCapture won't load specified properties as expected. I ... More

#3
Updated by Andrey Kamaev over 12 years ago

  • Category changed from highgui-images to highgui-camera

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