videoio.h

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/*
 * videoio.h
 *
 * Classes to support streaming video input (grabbing) and output.
 *
 * Portable Windows Library
 *
 * Copyright (c) 1993-2000 Equivalence Pty. Ltd.
 *
 * The contents of this file are subject to the Mozilla Public License
 * Version 1.0 (the "License"); you may not use this file except in
 * compliance with the License. You may obtain a copy of the License at
 * http://www.mozilla.org/MPL/
 *
 * Software distributed under the License is distributed on an "AS IS"
 * basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See
 * the License for the specific language governing rights and limitations
 * under the License.
 *
 * The Original Code is Portable Windows Library.
 *
 * The Initial Developer of the Original Code is Equivalence Pty. Ltd.
 *
 * Contributor(s): Mark Cooke ([e-mail])
 *
 * $Log: videoio.h,v $
 * Revision 1.40  2004/04/18 12:49:22  csoutheren
 * Patches to video code thanks to Guilhem Tardy (hope I get it right this time :)
 *
 * Revision 1.39  2004/01/18 14:23:30  dereksmithies
 * Add new function to make opening of video input devices easier.
 *
 * Revision 1.38  2004/01/02 23:30:18  rjongbloed
 * Removed extraneous static function for getting input device names that has been deprecated during the plug ins addition.
 *
 * Revision 1.37  2003/12/14 10:01:02  rjongbloed
 * Resolved issue with name space conflict os static and virtual forms of GetDeviceNames() function.
 *
 * Revision 1.36  2003/12/03 03:47:56  dereksmithies
 * Add fix so video output devices compile and run correctly.
 * Thanks to Craig Southeren.
 *
 * Revision 1.35  2003/11/19 04:29:02  csoutheren
 * Changed to support video output plugins
 *
 * Revision 1.34  2003/11/18 10:39:06  csoutheren
 * Fixed warnings regarding calling virtual Close in destructors
 *
 * Revision 1.33  2003/11/18 06:46:15  csoutheren
 * Changed to support video input plugins
 *
 * Revision 1.32  2003/09/17 05:41:59  csoutheren
 * Removed recursive includes
 *
 * Revision 1.31  2003/09/17 01:18:02  csoutheren
 * Removed recursive include file system and removed all references
 * to deprecated coooperative threading support
 *
 * Revision 1.30  2003/03/17 08:10:00  robertj
 * Fixed GNU warning
 *
 * Revision 1.29  2003/03/17 07:51:07  robertj
 * Added OpenFull() function to open with all video parameters in one go.
 * Made sure vflip variable is set in converter even if converter has not
 *   been set yet, should not depend on the order of functions!
 * Removed canCaptureVideo variable as this is really a virtual function to
 *   distinguish PVideoOutputDevice from PVideoInputDevice, it is not dynamic.
 * Made significant enhancements to PVideoOutputDevice class.
 * Added PVideoOutputDevice descendants for NULL and PPM files.
 *
 * Revision 1.28  2002/09/16 01:08:59  robertj
 * Added #define so can select if #pragma interface/implementation is used on
 *   platform basis (eg MacOS) rather than compiler, thanks Robert Monaghan.
 *
 * Revision 1.27  2002/04/12 08:25:12  robertj
 * Added text string output for tracing video format.
 *
 * Revision 1.26  2002/04/05 06:41:54  rogerh
 * Apply video changes from Damien Sandras <[e-mail]>.
 * The Video Channel and Format are no longer set in Open(). Instead
 * call the new SetVideoChannelFormat() method. This makes video capture
 * and GnomeMeeting more stable with certain Linux video capture devices.
 *
 * Revision 1.25  2002/02/20 02:37:26  dereks
 * Initial release of Firewire camera support for linux.
 * Many thanks to Ryutaroh Matsumoto <[e-mail]>.
 *
 * Revision 1.24  2002/01/16 07:51:06  robertj
 * MSVC compatibilty changes
 *
 * Revision 1.23  2002/01/16 03:51:20  dereks
 * Move flip methods in PVideoInputDevice  to  PVideoDevice
 *
 * Revision 1.22  2002/01/14 02:59:54  robertj
 * Added preferred colour format selection, thanks Walter Whitlock
 *
 * Revision 1.21  2002/01/04 04:11:45  dereks
 * Add video flip code from Walter Whitlock, which flips code at the grabber.
 *
 * Revision 1.20  2001/11/28 00:07:32  dereks
 * Locking added to PVideoChannel, allowing reader/writer to be changed mid call
 * Enabled adjustment of the video frame rate
 * New fictitous image, a blank grey area
 *
 * Revision 1.19  2001/08/06 06:12:45  rogerh
 * Fix comments
 *
 * Revision 1.18  2001/08/03 04:21:51  dereks
 * Add colour/size conversion for YUV422->YUV411P
 * Add Get/Set Brightness,Contrast,Hue,Colour for PVideoDevice,  and
 * Linux PVideoInputDevice.
 * Add lots of PTRACE statement for debugging colour conversion.
 * Add support for Sony Vaio laptop under linux. Requires 2.4.7 kernel.
 *
 * Revision 1.17  2001/05/22 23:38:45  robertj
 * Fixed bug in PVideoOutputDevice, removed redundent SetFrameSize.
 *
 * Revision 1.16  2001/05/22 12:49:32  robertj
 * Did some seriously wierd rewrite of platform headers to eliminate the
 *   stupid GNU compiler warning about braces not matching.
 *
 * Revision 1.15  2001/03/20 02:21:57  robertj
 * More enhancements from Mark Cooke
 *
 * Revision 1.14  2001/03/08 23:04:19  robertj
 * Fixed up some documentation.
 *
 * Revision 1.13  2001/03/08 08:31:34  robertj
 * Numerous enhancements to the video grabbing code including resizing
 *   infrastructure to converters. Thanks a LOT, Mark Cooke.
 *
 * Revision 1.12  2001/03/07 01:42:59  dereks
 * miscellaneous video fixes. Works on linux now. Add debug statements
 * (at PTRACE level of 1)
 *
 * Revision 1.11  2001/03/06 23:34:20  robertj
 * Added static function to get input device names.
 * Moved some inline virtuals to non-inline.
 *
 * Revision 1.10  2001/03/03 05:06:31  robertj
 * Major upgrade of video conversion and grabbing classes.
 *
 * Revision 1.9  2001/02/28 01:47:14  robertj
 * Removed function from ancestor and is not very useful, thanks Thorsten Westheider.
 *
 * Revision 1.8  2000/12/19 22:20:26  dereks
 * Add video channel classes to connect to the PwLib PVideoInputDevice class.
 * Add PFakeVideoInput class to generate test images for video.
 *
 * Revision 1.7  2000/11/09 00:20:38  robertj
 * Added qcif size constants
 *
 * Revision 1.6  2000/07/30 03:41:31  robertj
 * Added more colour formats to video device enum.
 *
 * Revision 1.5  2000/07/26 03:50:49  robertj
 * Added last error variable to video device.
 *
 * Revision 1.4  2000/07/26 02:13:46  robertj
 * Added some more "common" bounds checking to video device.
 *
 * Revision 1.3  2000/07/25 13:38:25  robertj
 * Added frame rate parameter to video frame grabber.
 *
 * Revision 1.2  2000/07/25 13:14:05  robertj
 * Got the video capture stuff going!
 *
 * Revision 1.1  2000/07/15 09:47:34  robertj
 * Added video I/O device classes.
 *
 */


#ifndef _PVIDEOIO
#define _PVIDEOIO

#ifdef P_USE_PRAGMA
#pragma interface
#endif

#if defined(_WIN32)
PWLIB_STATIC_LOAD_PLUGIN(PVideoInputDevice_VideoForWindows);
PWLIB_STATIC_LOAD_PLUGIN(PVideoInputDevice_FakeVideo);

PWLIB_STATIC_LOAD_PLUGIN(PVideoOutputDevice_NULLOutput);
#endif

class PColourConverter;

/**This class defines a video device.
   This class is used to abstract the few parameters that are common to both\
   input and output devices.

   Example colour formats are:

     "Grey"     Simple 8 bit linear grey scale
     "Gray"     Synonym for Grey
     "RGB32"    32 bit RGB
     "RGB24"    24 bit RGB
     "RGB565"   16 bit RGB (6 bit green)
     "RGB555"   15 bit RGB
     "YUV422"   YUV 4:2:2 packed
     "YUV422P"  YUV 4:2:2 planar
     "YUV411"   YUV 4:1:1 packed
     "YUV411P"  YUV 4:1:1 planar
     "YUV420"   YUV 4:2:0 packed
     "YUV420P"  YUV 4:2:0 planar
     "YUV410"   YUV 4:1:0 packed
     "YUV410P"  YUV 4:1:0 planar
     "MJPEG"    Motion JPEG
     "UYVY422"  YUV 4:2:2 packed as U Y V Y U Y V Y ...
     "UYV444    YUV 4:4:4 packed as U Y V   U Y V   ...
                They are used in IEEE 1394 digital cameras. The specification
                is found at
http://www.1394ta.org/Download/Technology/Specifications/2000/IIDC_Spec_v1_30.pdf

 */


class PVideoDevice : public PObject
{
  PCLASSINFO(PVideoDevice, PObject);

  protected:
    /** Create a new video device (input or output).
     */
    PVideoDevice();


  public:
    /** Delete structures created by PVideoDevice(); 
     */
    virtual ~PVideoDevice();

    enum VideoFormat {
      PAL,
      NTSC,
      SECAM,
      Auto,
      NumVideoFormats
    };

    enum StandardSizes {
      CIF16Width = 1408,
      CIF16Height = 1152,
      CIF4Width = 704,
      CIF4Height = 576,
      CIFWidth = 352,
      CIFHeight = 288,
      QCIFWidth = 176,
      QCIFHeight = 144,
      SQCIFWidth = 144,
      SQCIFHeight = 96,
    };

    struct OpenArgs {
      OpenArgs()
        : deviceName("#1"),
          videoFormat(Auto),
          channelNumber(0),
          colourFormat("YUV420P"),
          convertFormat(TRUE),
          rate(0),
          width(CIFWidth),
          height(CIFHeight),
          convertSize(TRUE),
          scaleSize(FALSE),
          flip(FALSE),
          brightness(-1),
          whiteness(-1),
          contrast(-1),
          colour(-1),
          hue(-1)
        { }
      PString     deviceName;
      VideoFormat videoFormat;
      int         channelNumber;
      PString     colourFormat;
      BOOL        convertFormat;
      unsigned    rate;
      unsigned    width;
      unsigned    height;
      BOOL        convertSize;
      BOOL        scaleSize;
      BOOL        flip;
      int         brightness;
      int         whiteness;
      int         contrast;
      int         colour;
      int         hue;
    };

    /**Open the device given the device name.
      */
    virtual BOOL OpenFull(
      const OpenArgs & args,      /// Parameters to set on opened device
      BOOL startImmediate = TRUE  /// Immediately start device
    );

    /**Open the device given the device name.
      */
    virtual BOOL Open(
      const PString & deviceName,   /// Device name to open
      BOOL startImmediate = TRUE    /// Immediately start device
    ) = 0;

    /**Determine if the device is currently open.
      */
    virtual BOOL IsOpen() = 0;

    /**Close the device.
      */
    virtual BOOL Close() = 0;

    /**Start the video device I/O capture.
      */
    virtual BOOL Start() = 0;

    /**Stop the video device I/O capture.
      */
    virtual BOOL Stop() = 0;


    /**Get the device name of the open device.
      */
    const PString & GetDeviceName() const
      { return deviceName; }

    /**Get a list of all of the drivers available.
      */
    virtual PStringList GetDeviceNames() const = 0;

#if PTRACING
    friend ostream & operator<<(ostream &, VideoFormat);
#endif

    /**Set the video format to be used.

       Default behaviour sets the value of the videoFormat variable and then
       returns TRUE.
    */
    virtual BOOL SetVideoFormat(
      VideoFormat videoFormat   /// New video format
    );

    /**Get the video format being used.

       Default behaviour returns the value of the videoFormat variable.
    */
    virtual VideoFormat GetVideoFormat() const;

    /**Get the number of video channels available on the device.

       Default behaviour returns 1.
    */
    virtual int GetNumChannels();

    /**Set the video channel to be used on the device.
       The channel number is an integer from 0 to GetNumChannels()-1. The
       special value of -1 will find the first working channel number.

       Default behaviour sets the value of the channelNumber variable and then
       returns TRUE.
    */
    virtual BOOL SetChannel(
      int channelNumber  /// New channel number for device.
    );

    /**Get the video channel to be used on the device.

       Default behaviour returns the value of the channelNumber variable.
    */
    virtual int GetChannel() const;

    /**Set the colour format to be used, trying converters if available.

       This function will set the colour format on the device to one that
       is compatible with a registered converter, and install that converter
       so that the correct format is used.
    */
    virtual BOOL SetColourFormatConverter(
      const PString & colourFormat // New colour format for device.
    );

    /**Set the colour format to be used.
       Note that this function does not do any conversion. If it returns TRUE
       then the video device does the colour format in native mode.

       To utilise an internal converter use the SetColourFormatConverter()
       function.

       Default behaviour sets the value of the colourFormat variable and then
       returns TRUE.
    */
    virtual BOOL SetColourFormat(
      const PString & colourFormat // New colour format for device.
    );

    /**Get the colour format to be used.

       Default behaviour returns the value of the colourFormat variable.
    */
    const PString & GetColourFormat() const;

    /**Set the video frame rate to be used on the device.

       Default behaviour sets the value of the frameRate variable and then
       returns TRUE.
    */
    virtual BOOL SetFrameRate(
      unsigned rate  /// Frames  per second
    );

    /**Get the video frame rate used on the device.

       Default behaviour returns the value of the frameRate variable.
    */
    virtual unsigned GetFrameRate() const;

    /**Get the minimum & maximum size of a frame on the device.

       Default behaviour returns the value 1 to UINT_MAX for both and returns
       FALSE.
    */
    virtual BOOL GetFrameSizeLimits(
      unsigned & minWidth,   /// Variable to receive minimum width
      unsigned & minHeight,  /// Variable to receive minimum height
      unsigned & maxWidth,   /// Variable to receive maximum width
      unsigned & maxHeight   /// Variable to receive maximum height
    ) ;


    /**Set the frame size to be used, trying converters if available.

       If the device does not support the size, a set of alternate resolutions
       are attempted.  A converter is setup if possible.
    */
    virtual BOOL SetFrameSizeConverter(
      unsigned width,        /// New width of frame
      unsigned height,       /// New height of frame
      BOOL     bScaleNotCrop /// Scale or crop/pad preference
    );

    /**Set the frame size to be used.

       Note that devices may not be able to produce the requested size, and
       this function will fail.  See SetFrameSizeConverter().

       Default behaviour sets the frameWidth and frameHeight variables and
       returns TRUE.
    */
    virtual BOOL SetFrameSize(
      unsigned width,   /// New width of frame
      unsigned height   /// New height of frame
    );

    /**Get the frame size being used.

       Default behaviour returns the value of the frameWidth and frameHeight
       variable and returns TRUE.
    */
    virtual BOOL GetFrameSize(
      unsigned & width,
      unsigned & height
    );

    /** Get the width of the frame being used.

        Default  behaviour returns the value of the frameWidth variable
    */
    virtual unsigned GetFrameWidth() const;

    /** Get the height of the frame being used.

        Default  behaviour returns the value of the frameHeight variable
    */
    virtual unsigned GetFrameHeight() const;

    /**Get the maximum frame size in bytes.

       Note a particular device may be able to provide variable length
       frames (eg motion JPEG) so will be the maximum size of all frames.
      */
    virtual PINDEX GetMaxFrameBytes() = 0;

    /** Get the number of bytes of an image, given a particular width, height and colour format.
      */
    static unsigned CalculateFrameBytes( 
      unsigned width,
      unsigned height,
      const PString & colourFormat
    );

    
    /**Get the last error code. This is a platform dependent number.
      */
    int GetLastError() const { return lastError; }


    /** Is the device a camera, and obtain video
     */
    virtual BOOL CanCaptureVideo() const = 0;