JeVoisBase  1.5
JeVois Smart Embedded Machine Vision Toolkit Base Modules
Share this page:
SaveVideo Class Reference

Save captured camera frames into a video file. More...

Inheritance diagram for SaveVideo:
Collaboration diagram for SaveVideo:

Public Member Functions

 SaveVideo (std::string const &instance)
 Constructor. More...
 
void postInit () override
 Get started. More...
 
void postUninit () override
 Get stopped. More...
 
virtual ~SaveVideo ()
 Virtual destructor for safe inheritance. More...
 
void process (jevois::InputFrame &&inframe, jevois::OutputFrame &&outframe) override
 Processing function, version that also shows a debug video output. More...
 
void process (jevois::InputFrame &&inframe) override
 Processing function, version with no video output. More...
 
void parseSerial (std::string const &str, std::shared_ptr< jevois::UserInterface > s) override
 Receive a string from a serial port which contains a user command. More...
 
void supportedCommands (std::ostream &os) override
 Human-readable description of this Module's supported custom commands. More...
 
- Public Member Functions inherited from jevois::Module
 Module (std::string const &instance)
 
virtual ~Module ()
 
virtual void sendSerial (std::string const &str)
 
 JEVOIS_DEFINE_ENUM_CLASS (SerStyle,(Terse)(Normal)(Detail)(Fine)) JEVOIS_DECLARE_PARAMETER(serstyle
 
 JEVOIS_DECLARE_PARAMETER (serprec, unsigned int, "Number of decimal points in standardized serial messages as " "defined in http://jevois.org/doc/UserSerialStyle.html", 0U, ParamCateg)
 
- Public Member Functions inherited from jevois::Component
 Component (std::string const &instance)
 
virtual ~Component ()
 
std::shared_ptr< ComponentgetSubComponent (std::string const &instance) const
 
std::shared_ptr< Comp > addSubComponent (std::string const &instance, Args &&...args)
 
void removeSubComponent (std::shared_ptr< Comp > &component)
 
void removeSubComponent (std::string const &instance, bool warnIfNotFound=true)
 
std::shared_ptr< Comp > getSubComponent (std::string const &instance) const
 
bool isTopLevel () const
 
bool initialized () const
 
std::string const & className () const
 
std::string const & instanceName () const
 
std::vector< std::string > setParamVal (std::string const &paramdescriptor, T const &val)
 
void setParamValUnique (std::string const &paramdescriptor, T const &val)
 
std::vector< std::pair< std::string, T > > getParamVal (std::string const &paramdescriptor) const
 
getParamValUnique (std::string const &paramdescriptor) const
 
std::vector< std::string > setParamString (std::string const &paramdescriptor, std::string const &val)
 
void setParamStringUnique (std::string const &paramdescriptor, std::string const &val)
 
std::vector< std::pair< std::string, std::string > > getParamString (std::string const &paramdescriptor) const
 
std::string getParamStringUnique (std::string const &paramdescriptor) const
 
void freezeParam (std::string const &paramdescriptor)
 
void unFreezeParam (std::string const &paramdescriptor)
 
void freezeAllParams ()
 
void unFreezeAllParams ()
 
std::string descriptor () const
 
void setParamsFromFile (std::string const &filename)
 
std::istream & setParamsFromStream (std::istream &is, std::string const &absfile)
 
void setPath (std::string const &path)
 
std::string absolutePath (std::string const &path="")
 
std::shared_ptr< Comp > addSubComponent (std::string const &instance, Args &&...args)
 
void removeSubComponent (std::shared_ptr< Comp > &component)
 
void removeSubComponent (std::string const &instance, bool warnIfNotFound=true)
 
std::shared_ptr< Comp > getSubComponent (std::string const &instance) const
 
bool isTopLevel () const
 
bool initialized () const
 
std::string const & className () const
 
std::string const & instanceName () const
 
std::vector< std::string > setParamVal (std::string const &paramdescriptor, T const &val)
 
void setParamValUnique (std::string const &paramdescriptor, T const &val)
 
std::vector< std::pair< std::string, T > > getParamVal (std::string const &paramdescriptor) const
 
getParamValUnique (std::string const &paramdescriptor) const
 
std::vector< std::string > setParamString (std::string const &paramdescriptor, std::string const &val)
 
void setParamStringUnique (std::string const &paramdescriptor, std::string const &val)
 
std::vector< std::pair< std::string, std::string > > getParamString (std::string const &paramdescriptor) const
 
std::string getParamStringUnique (std::string const &paramdescriptor) const
 
void freezeParam (std::string const &paramdescriptor)
 
void unFreezeParam (std::string const &paramdescriptor)
 
void freezeAllParams ()
 
void unFreezeAllParams ()
 
std::string descriptor () const
 
void setParamsFromFile (std::string const &filename)
 
std::istream & setParamsFromStream (std::istream &is, std::string const &absfile)
 
void setPath (std::string const &path)
 
std::string absolutePath (std::string const &path="")
 
- Public Member Functions inherited from jevois::ParameterRegistry
virtual ~ParameterRegistry ()
 

Protected Member Functions

void run ()
 
- Protected Member Functions inherited from jevois::Component
virtual void preInit ()
 
virtual void preUninit ()
 
virtual void preInit ()
 
virtual void preUninit ()
 
- Protected Member Functions inherited from jevois::ParameterRegistry
void addParameter (ParameterBase *const param)
 
void removeParameter (ParameterBase *const param)
 
void callbackInitCall ()
 

Protected Attributes

std::future< void > itsRunFut
 
jevois::BoundedBuffer< cv::Mat, jevois::BlockingBehavior::Block, jevois::BlockingBehavior::BlockitsBuf
 
std::atomic< bool > itsSaving
 
int itsFileNum
 
std::atomic< bool > itsRunning
 
std::string itsFilename
 

Related Functions

(Note that these are not member functions.)

 JEVOIS_DECLARE_PARAMETER (filename, std::string, "Name of the video file to write. If path is not absolute, " PATHPREFIX " will be prepended to it. Name should contain a printf-like directive for " "one int argument, which will start at 0 and be incremented on each streamoff command.", "video%06d.avi", ParamCateg)
 Parameter. More...
 
 JEVOIS_DECLARE_PARAMETER (fourcc, std::string, "FourCC of the codec to use. The OpenCV VideoWriter doc is unclear " "as to which codecs are supported. Presumably, the ffmpeg library is used inside OpenCV. " "Hence any video encoder supported by ffmpeg should work. Tested codecs include: MJPG, " "MP4V, AVC1. Make sure you also pick the right filename extension (e.g., .avi for MJPG, " ".mp4 for MP4V, etc)", "MJPG", boost::regex("^\4}$"), ParamCateg)
 Parameter. More...
 
 JEVOIS_DECLARE_PARAMETER (fps, double, "Video frames/sec as stored in the file and to be used both for recording and " "playback. Beware that the video writer will drop frames if you are capturing faster than " "the frame rate specified here. For example, if capturing at 120fps, be sure to set this " "parameter to 120, otherwise by default the saved video will be at 30fps even though capture " "was running at 120fps.", 30.0, ParamCateg)
 Parameter. More...
 

Detailed Description

Save captured camera frames into a video file.

This module records video and saves it to the MicroSD card inside the JeVois smart camera. It is useful, for example, to record footage that will be used to train some machine vision algorithm.

Issue the command start over the command-line interface to start saving video frames, and stop to stop saving. Successive start/stop commands will increment the file number (d argument in the 'filename' parameter. Before a file is written, the module checks whether it already exists, and, if so, skips over it by incrementing the file number. See Command-line interface user guide for details on how to use the command-line interface.

This module works with any video resolution and pixel format supported by the camera sensor. Thus, additional video mappings are possible beyond the ones listed here.

See Advanced topic: Image pixel formats for information about pixel formats; with SaveVideo you can use the formats supported by the camera sensor: YUYV, BAYER, RGB565

This module accepts any resolution supported by the JeVois camera sensor:

  • SXGA (1280 x 1024): up to 15 fps
  • VGA (640 x 480): up to 30 fps
  • CIF (352 x 288): up to 60 fps
  • QVGA (320 x 240): up to 60 fps
  • QCIF (176 x 144): up to 120 fps
  • QQVGA (160 x 120): up to 60 fps
  • QQCIF (88 x 72): up to 120 fps

This module can operate both with USB video output, or no USB video output.

When using with no USB output (NONE output format), you should first issue a streamon command to start video streaming, then 'start'. The 'streamon' is not necessary when using with a USB video output, the host computer over USB triggers video streaming when it starts grabbing frames from the JeVois camera.

This module internally uses the OpenCV VideoWriter class to compress and write the video file. See the OpenCV documentation for which video formats are supported.

You should be aware of two things when attempting video recording at high frame rates:

  • If using a video mapping with USB output, the frame rate may be limited by the maximum rate at which the host computer can grab and display. On many host computers, for example, the display refresh rate might be 60Hz. Using a video capture software on these computers is likely going to limit the maximum display rate to 60 frames/s and that will in turn limit the capture and saving rate. This is not an issue when using a video mapping with no USB output.
  • The fps parameter should be set to the rate at which you want to save video. If you capture at 60 frames/s according to your video mapping but fps is set to 30, saving will be at 30 fps. This limitation of rate is done internally by the OpenCV VideoWriter. So just make sure that you set the fps parameter to the rate at which you want to save.

Note that this module may suffer from DMA coherency artifacts if the camturbo parameter of the jevois::Engine is turned on, which it is by default. The camturbo parameter relaxes some of the cache coherency constraints on the video buffers captured by the camera sensor, which allows the JeVois processor to access video pixel data from memory faster. But with modules that do not do much processing, sometimes this yields video artifacts, we presume because some of the video data from previous frames still is in the CPU cache and hence is not again fetched from main memory by the CPU. If you see short stripes of what appears to be wrong pixel colors in the video, try to disable camturbo: edit JEVOIS:/config/params.cfg on your MicroSD card and in there turn camturbo to false.

Author
Laurent Itti
Videomapping:
YUYV 320 240 60.0 YUYV 320 240 60.0 JeVois SaveVideo
Videomapping:
YUYV 320 240 30.0 YUYV 320 240 30.0 JeVois SaveVideo
Videomapping:
NONE 0 0 0 YUYV 320 240 60.0 JeVois SaveVideo
Videomapping:
NONE 0 0 0 YUYV 320 240 30.0 JeVois SaveVideo
Videomapping:
NONE 0 0 0 YUYV 176 144 120.0 JeVois SaveVideo
Custom module command:
start - start saving video
Custom module command:
stop - stop saving video and increment video file number
Email:
itti@usc.edu
Address:
University of Southern California, HNB-07A, 3641 Watt Way, Los Angeles, CA 90089-2520, USA
Main URL:
http://jevois.org
Support URL:
http://jevois.org/doc
Other URL:
http://iLab.usc.edu
License:
GPL v3
Distribution:
Unrestricted
Restrictions:
None

Definition at line 137 of file SaveVideo.C.

Constructor & Destructor Documentation

◆ SaveVideo()

SaveVideo::SaveVideo ( std::string const &  instance)
inline

Constructor.

Definition at line 144 of file SaveVideo.C.

◆ ~SaveVideo()

virtual SaveVideo::~SaveVideo ( )
inlinevirtual

Virtual destructor for safe inheritance.

Definition at line 181 of file SaveVideo.C.

Member Function Documentation

◆ parseSerial()

void SaveVideo::parseSerial ( std::string const &  str,
std::shared_ptr< jevois::UserInterface s 
)
inlineoverridevirtual

Receive a string from a serial port which contains a user command.

Reimplemented from jevois::Module.

Definition at line 240 of file SaveVideo.C.

References jevois::BoundedBuffer< T, WhenFull, WhenEmpty >::filled_size(), itsBuf, itsFilename, itsSaving, LERROR, LINFO, jevois::BoundedBuffer< T, WhenFull, WhenEmpty >::push(), jevois::Module::sendSerial(), and system().

◆ postInit()

void SaveVideo::postInit ( )
inlineoverridevirtual

Get started.

Reimplemented from jevois::Component.

Definition at line 151 of file SaveVideo.C.

References itsRunFut, itsRunning, and run().

◆ postUninit()

◆ process() [1/2]

◆ process() [2/2]

void SaveVideo::process ( jevois::InputFrame &&  inframe)
inlineoverridevirtual

◆ run()

void SaveVideo::run ( )
inlineprotected

◆ supportedCommands()

void SaveVideo::supportedCommands ( std::ostream &  os)
inlineoverridevirtual

Human-readable description of this Module's supported custom commands.

Reimplemented from jevois::Module.

Definition at line 271 of file SaveVideo.C.

Friends And Related Function Documentation

◆ JEVOIS_DECLARE_PARAMETER() [1/3]

JEVOIS_DECLARE_PARAMETER ( filename  ,
std::string  ,
"Name of the video file to write. If path is not  absolute,
" PATHPREFIX " will be prepended to it. Name should contain a printf-like directive for " "one int  argument,
which will start at 0 and be incremented on each streamoff command."  ,
"video%06d.avi"  ,
ParamCateg   
)
related

Parameter.

◆ JEVOIS_DECLARE_PARAMETER() [2/3]

JEVOIS_DECLARE_PARAMETER ( fourcc  ,
std::string  ,
"FourCC of the codec to use. The OpenCV VideoWriter doc is unclear " "as to which codecs are supported.  Presumably,
the ffmpeg library is used inside OpenCV. " "Hence any video encoder supported by ffmpeg should work. Tested codecs include:MJPG  ,
" "  MP4V,
AVC1. Make sure you also pick the right filename extension(e.g.,.avi for MJPG, " ".mp4 for MP4V, etc)"  ,
"MJPG"  ,
boost::regex("^\}$")  ,
ParamCateg   
)
related

Parameter.

◆ JEVOIS_DECLARE_PARAMETER() [3/3]

JEVOIS_DECLARE_PARAMETER ( fps  ,
double  ,
"Video frames/sec as stored in the file and to be used both for recording and " "playback. Beware that the video writer will drop frames if you are capturing faster than " "the frame rate specified here. For  example,
if capturing at  120fps,
be sure to set this " "parameter to  120,
otherwise by default the saved video will be at 30fps even though capture " "was running at 120fps."  ,
30.  0,
ParamCateg   
)
related

Parameter.

Member Data Documentation

◆ itsBuf

Definition at line 341 of file SaveVideo.C.

Referenced by parseSerial(), postUninit(), process(), and run().

◆ itsFilename

std::string SaveVideo::itsFilename
protected

Definition at line 345 of file SaveVideo.C.

Referenced by parseSerial(), postUninit(), process(), and run().

◆ itsFileNum

int SaveVideo::itsFileNum
protected

Definition at line 343 of file SaveVideo.C.

Referenced by run().

◆ itsRunFut

std::future<void> SaveVideo::itsRunFut
protected

Definition at line 340 of file SaveVideo.C.

Referenced by postInit(), and postUninit().

◆ itsRunning

std::atomic<bool> SaveVideo::itsRunning
protected

Definition at line 344 of file SaveVideo.C.

Referenced by postInit(), postUninit(), and run().

◆ itsSaving

std::atomic<bool> SaveVideo::itsSaving
protected

Definition at line 342 of file SaveVideo.C.

Referenced by parseSerial(), and process().


The documentation for this class was generated from the following file: