V4L (V4L2): Refactoring. Added missed camera properties. Fixed getting `INF` for some properties. Singlethread as always (#12893)
* cap_v4l:
1 Added cap_properties verbalization.
2 Set Get of properties elementary refactoring.
3 Removed converting parameters to/from [0,1] range.
4 Added all known conversion from V4L2_CID_* to CV_CAP_PROP_*
* cap_v4l:
1. Removed all query for parameters range.
2. Refactored capture initialization.
3. Added selecting input channel by CV_CAP_PROP_MODE. Default value -1 the channels not changed.
* cap_v4l:
1. Refactoring of Convert To RGB
* cap_v4l:
1. Fixed use of video buffer index.
2. Removed extra memcopy for grab image.
3. Removed device closing from autosetup_capture_mode_v4l2
* cap_v4l:
1. The `goto` was eliminated
2. Fixed use of temporary buffer index for V4L2_PIX_FMT_SN9C10X
3. Fixed use of the bufferIndex
4. Removed trailing spaces and unused variables.
* cap_v4l:
1. Alias for capture->buffers[capture->bufferIndex]
2. Reduced size of data for memcpy: bytesused instead of length
3. Refactoring. Code duplication. More info for debug
* cap_v4l:
1. Added the ability to grab and retrieveFrame independently several times
* cap_v4l:
1. Not need to close/open device for new capture parameters applying.
2. Removed using of device name as a flag that the capture is closed. Added sufficient function.
3. Refactoring. Added requestBuffers and createBuffers
* cap_v4l:
1. Added tryIoctl with `select` like was in mainloop_v4l2.
2. Fixed buffer request for device without closing the device.
3. Some static function moved to CvCaptureCAM_V4L
4. Removed unused defines
* cap_v4l:
1. Thread-safe now
* cap_v4l:
1. Fixed thread-safe destructor
2. Fixed FPS setting
* Missed brake
* Removed thread-safety
* cap_v4l:
1. Reverted conversion parameters to/from [0,1] by default for backward compatibility.
2. Added setting for turn off compatibility mode: set CV_CAP_PROP_MODE to 65536
3. Most static functions moved to CvCaptureCAM_V4L
4. Refactoring of icvRetrieveFrameCAM_V4L and using of frame_allocated flag
* cap_v4l:
1. Added conversion to RGB from NV12, NV21
2. Refactoring. Removed wrappers for known format conversions.
* Added `CAP_PROP_CHANNEL` to the enum VideoCaptureProperties.
CAP_V4L migrated to use VideoCaptureProperties.
* 1. Update comments.
2. Environment variable `OPENCV_VIDEOIO_V4L_RANGE_NORMALIZED` for setting default backward compatibility mode.
3. Revert getting of `CAP_PROP_MODE` as fourcc code in backward compatibility mode.
* videoio: update cap_v4l - compatibilityMode => normalizePropRange
* videoio(test): V4L2 MJPEG test
`v4l2-ctl --list-formats` should have 'MJPG' entry
* videoio: fix buffer initialization
to avoid "munmap: Invalid argument" messages
The `codec_tag` is only available when opening a file from disk. If `AVStream` is a network stream then `fourcc` must be obtained using `codec_id`. I have tested the following scenarios:
1) Open a `.mp4` file and verify that `codec_tag` is returned (old behavior)
2) Open a `rtsp` stream and verify that `codec_fourcc` is returned (Tested with a MJPEG, H264 and H265 stream)
* may be an typo fix
* remove identical branch,may be paste error
* add parentheses around macro parameter
* simplify if condition
* check malloc fail
* change the condition of branch removed by commit 3041502861
Currently the private control enumeration will be stopped when QUERYCTRL
returns -EINVAL only. It is possible however that other errors occur.
One particular case is when the v4l2 device doesn't support any controls
and doesn't implement the QUERYCTRL ioctl. In that case the v4l2
framework returns -ENOTTY. In that case the current control enumeration
will go in an endless loop.
To fix this change the control enumeration stop condition. If any errors
occur, end the control enumeration.
Signed-off-by: Todor Tomov <todor.tomov@linaro.org>
the static variables will cause race-condition when operating in
multithread scenarios.
Signed-off-by: Teng Yiliang <ylteng@outlook.com>
Signed-off-by: Teng Yiliang <yiliang.teng@weimob.com>
Synchronized reading from camera with heavy frame processing
provides bad effects (huge frame latency, processing frames from the past).
Generally, there is no way to process each frame and some frames will be dropped.
Allow preventive frame dropping to reduce lag of processed frames.
This mode is applied to cameras only (opened by 'index').
Using codec->time_base is deprecated to specify muxer settings.
Resolves issue with FPS value for AVI files with FFmpeg 4.0.
Related FFmpeg commits:
- 194be1f43e
- 91736025b2
