tkimgphoto.c

linux系统下的音频通信

/*
 * tkImgPhoto.c --
 *
 *	Implements images of type "photo" for Tk.  Photo images are
 *	stored in full color (24 bits per pixel) and displayed using
 *	dithering if necessary.
 *
 * Copyright (c) 1994 The Australian National University.
 * Copyright (c) 1994-1997 Sun Microsystems, Inc.
 *
 * See the file "license.terms" for information on usage and redistribution
 * of this file, and for a DISCLAIMER OF ALL WARRANTIES.
 *
 * Author: Paul Mackerras ([e-mail]),
 *	   Department of Computer Science,
 *	   Australian National University.
 *
 * SCCS: @(#) tkImgPhoto.c 1.60 97/08/08 11:32:46
 */

#include "tkInt.h"
#include "tkPort.h"
#include "tclMath.h"
#include <ctype.h>

/*
 * Declaration for internal Xlib function used here:
 */

extern _XInitImageFuncPtrs _ANSI_ARGS_((XImage *image));

/*
 * A signed 8-bit integral type.  If chars are unsigned and the compiler
 * isn't an ANSI one, then we have to use short instead (which wastes
 * space) to get signed behavior.
 */

#if defined(__STDC__) || defined(_AIX)
    typedef signed char schar;
#else
#   ifndef __CHAR_UNSIGNED__
	typedef char schar;
#   else
	typedef short schar;
#   endif
#endif

/*
 * An unsigned 32-bit integral type, used for pixel values.
 * We use int rather than long here to accommodate those systems
 * where longs are 64 bits.
 */

typedef unsigned int pixel;

/*
 * The maximum number of pixels to transmit to the server in a
 * single XPutImage call.
 */

#define MAX_PIXELS 65536

/*
 * The set of colors required to display a photo image in a window depends on:
 *	- the visual used by the window
 *	- the palette, which specifies how many levels of each primary
 *	  color to use, and
 *	- the gamma value for the image.
 *
 * Pixel values allocated for specific colors are valid only for the
 * colormap in which they were allocated.  Sets of pixel values
 * allocated for displaying photos are re-used in other windows if
 * possible, that is, if the display, colormap, palette and gamma
 * values match.  A hash table is used to locate these sets of pixel
 * values, using the following data structure as key:
 */

typedef struct {
    Display *display;		/* Qualifies the colormap resource ID */
    Colormap colormap;		/* Colormap that the windows are using. */
    double gamma;		/* Gamma exponent value for images. */
    Tk_Uid palette;		/* Specifies how many shades of each primary
				 * we want to allocate. */
} ColorTableId;

/*
 * For a particular (display, colormap, palette, gamma) combination,
 * a data structure of the following type is used to store the allocated
 * pixel values and other information:
 */

typedef struct ColorTable {
    ColorTableId id;		/* Information used in selecting this
				 * color table. */
    int	flags;			/* See below. */
    int	refCount;		/* Number of instances using this map. */
    int liveRefCount;		/* Number of instances which are actually
				 * in use, using this map. */
    int	numColors;		/* Number of colors allocated for this map. */

    XVisualInfo	visualInfo;	/* Information about the visual for windows
				 * using this color table. */

    pixel redValues[256];	/* Maps 8-bit values of red intensity
				 * to a pixel value or index in pixelMap. */
    pixel greenValues[256];	/* Ditto for green intensity */
    pixel blueValues[256];	/* Ditto for blue intensity */
    unsigned long *pixelMap;	/* Actual pixel values allocated. */

    unsigned char colorQuant[3][256];
				/* Maps 8-bit intensities to quantized
				 * intensities.  The first index is 0 for
				 * red, 1 for green, 2 for blue. */
} ColorTable;

/*
 * Bit definitions for the flags field of a ColorTable.
 * BLACK_AND_WHITE:		1 means only black and white colors are
 *				available.
 * COLOR_WINDOW:		1 means a full 3-D color cube has been
 *				allocated.
 * DISPOSE_PENDING:		1 means a call to DisposeColorTable has
 *				been scheduled as an idle handler, but it
 *				hasn't been invoked yet.
 * MAP_COLORS:			1 means pixel values should be mapped
 *				through pixelMap.
 */

#define BLACK_AND_WHITE		1
#define COLOR_WINDOW		2
#define DISPOSE_PENDING		4
#define MAP_COLORS		8

/*
 * Definition of the data associated with each photo image master.
 */

typedef struct PhotoMaster {
    Tk_ImageMaster tkMaster;	/* Tk's token for image master.  NULL means
				 * the image is being deleted. */
    Tcl_Interp *interp;		/* Interpreter associated with the
				 * application using this image. */
    Tcl_Command imageCmd;	/* Token for image command (used to delete
				 * it when the image goes away).  NULL means
				 * the image command has already been
				 * deleted. */
    int	flags;			/* Sundry flags, defined below. */
    int	width, height;		/* Dimensions of image. */
    int userWidth, userHeight;	/* User-declared image dimensions. */
    Tk_Uid palette;		/* User-specified default palette for
				 * instances of this image. */
    double gamma;		/* Display gamma value to correct for. */
    char *fileString;		/* Name of file to read into image. */
    char *dataString;		/* String value to use as contents of image. */
    char *format;		/* User-specified format of data in image
				 * file or string value. */
    unsigned char *pix24;	/* Local storage for 24-bit image. */
    int ditherX, ditherY;	/* Location of first incorrectly
				 * dithered pixel in image. */
    TkRegion validRegion;	/* Tk region indicating which parts of
				 * the image have valid image data. */
    struct PhotoInstance *instancePtr;
				/* First in the list of instances
				 * associated with this master. */
} PhotoMaster;

/*
 * Bit definitions for the flags field of a PhotoMaster.
 * COLOR_IMAGE:			1 means that the image has different color
 *				components.
 * IMAGE_CHANGED:		1 means that the instances of this image
 *				need to be redithered.
 */

#define COLOR_IMAGE		1
#define IMAGE_CHANGED		2

/*
 * The following data structure represents all of the instances of
 * a photo image in windows on a given screen that are using the
 * same colormap.
 */

typedef struct PhotoInstance {
    PhotoMaster *masterPtr;	/* Pointer to master for image. */
    Display *display;		/* Display for windows using this instance. */
    Colormap colormap;		/* The image may only be used in windows with
				 * this particular colormap. */
    struct PhotoInstance *nextPtr;
				/* Pointer to the next instance in the list
				 * of instances associated with this master. */
    int refCount;		/* Number of instances using this structure. */
    Tk_Uid palette;		/* Palette for these particular instances. */
    double gamma;		/* Gamma value for these instances. */
    Tk_Uid defaultPalette;	/* Default palette to use if a palette
				 * is not specified for the master. */
    ColorTable *colorTablePtr;	/* Pointer to information about colors
				 * allocated for image display in windows
				 * like this one. */
    Pixmap pixels;		/* X pixmap containing dithered image. */
    int width, height;		/* Dimensions of the pixmap. */
    schar *error;		/* Error image, used in dithering. */
    XImage *imagePtr;		/* Image structure for converted pixels. */
    XVisualInfo visualInfo;	/* Information about the visual that these
				 * windows are using. */
    GC gc;			/* Graphics context for writing images
				 * to the pixmap. */
} PhotoInstance;

/*
 * The following data structure is used to return information
 * from ParseSubcommandOptions:
 */

struct SubcommandOptions {
    int options;		/* Individual bits indicate which
				 * options were specified - see below. */
    char *name;			/* Name specified without an option. */
    int fromX, fromY;		/* Values specified for -from option. */
    int fromX2, fromY2;		/* Second coordinate pair for -from option. */
    int toX, toY;		/* Values specified for -to option. */
    int toX2, toY2;		/* Second coordinate pair for -to option. */
    int zoomX, zoomY;		/* Values specified for -zoom option. */
    int subsampleX, subsampleY;	/* Values specified for -subsample option. */
    char *format;		/* Value specified for -format option. */
};

/*
 * Bit definitions for use with ParseSubcommandOptions:
 * Each bit is set in the allowedOptions parameter on a call to
 * ParseSubcommandOptions if that option is allowed for the current
 * photo image subcommand.  On return, the bit is set in the options
 * field of the SubcommandOptions structure if that option was specified.
 *
 * OPT_FORMAT:			Set if -format option allowed/specified.
 * OPT_FROM:			Set if -from option allowed/specified.
 * OPT_SHRINK:			Set if -shrink option allowed/specified.
 * OPT_SUBSAMPLE:		Set if -subsample option allowed/spec'd.
 * OPT_TO:			Set if -to option allowed/specified.
 * OPT_ZOOM:			Set if -zoom option allowed/specified.
 */

#define OPT_FORMAT	1
#define OPT_FROM	2
#define OPT_SHRINK	4
#define OPT_SUBSAMPLE	8
#define OPT_TO		0x10
#define OPT_ZOOM	0x20

/*
 * List of option names.  The order here must match the order of
 * declarations of the OPT_* constants above.
 */

static char *optionNames[] = {
    "-format",
    "-from",
    "-shrink",
    "-subsample",
    "-to",
    "-zoom",
    (char *) NULL
};

/*
 * The type record for photo images:
 */

static int		ImgPhotoCreate _ANSI_ARGS_((Tcl_Interp *interp,
			    char *name, int argc, char **argv,
			    Tk_ImageType *typePtr, Tk_ImageMaster master,
			    ClientData *clientDataPtr));
static ClientData	ImgPhotoGet _ANSI_ARGS_((Tk_Window tkwin,
			    ClientData clientData));
static void		ImgPhotoDisplay _ANSI_ARGS_((ClientData clientData,
			    Display *display, Drawable drawable,
			    int imageX, int imageY, int width, int height,
			    int drawableX, int drawableY));
static void		ImgPhotoFree _ANSI_ARGS_((ClientData clientData,
			    Display *display));
static void		ImgPhotoDelete _ANSI_ARGS_((ClientData clientData));

Tk_ImageType tkPhotoImageType = {
    "photo",			/* name */
    ImgPhotoCreate,		/* createProc */
    ImgPhotoGet,		/* getProc */
    ImgPhotoDisplay,		/* displayProc */
    ImgPhotoFree,		/* freeProc */
    ImgPhotoDelete,		/* deleteProc */
    (Tk_ImageType *) NULL	/* nextPtr */
};

/*
 * Default configuration
 */

#define DEF_PHOTO_GAMMA		"1"
#define DEF_PHOTO_HEIGHT	"0"
#define DEF_PHOTO_PALETTE	""
#define DEF_PHOTO_WIDTH		"0"

/*
 * Information used for parsing configuration specifications:
 */
static Tk_ConfigSpec configSpecs[] = {
    {TK_CONFIG_STRING, "-data", (char *) NULL, (char *) NULL,
	 (char *) NULL, Tk_Offset(PhotoMaster, dataString), TK_CONFIG_NULL_OK},
    {TK_CONFIG_STRING, "-format", (char *) NULL, (char *) NULL,
	 (char *) NULL, Tk_Offset(PhotoMaster, format), TK_CONFIG_NULL_OK},
    {TK_CONFIG_STRING, "-file", (char *) NULL, (char *) NULL,
	 (char *) NULL, Tk_Offset(PhotoMaster, fileString), TK_CONFIG_NULL_OK},
    {TK_CONFIG_DOUBLE, "-gamma", (char *) NULL, (char *) NULL,
	 DEF_PHOTO_GAMMA, Tk_Offset(PhotoMaster, gamma), 0},
    {TK_CONFIG_INT, "-height", (char *) NULL, (char *) NULL,
	 DEF_PHOTO_HEIGHT, Tk_Offset(PhotoMaster, userHeight), 0},
    {TK_CONFIG_UID, "-palette", (char *) NULL, (char *) NULL,
	 DEF_PHOTO_PALETTE, Tk_Offset(PhotoMaster, palette), 0},
    {TK_CONFIG_INT, "-width", (char *) NULL, (char *) NULL,
	 DEF_PHOTO_WIDTH, Tk_Offset(PhotoMaster, userWidth), 0},
    {TK_CONFIG_END, (char *) NULL, (char *) NULL, (char *) NULL,
	 (char *) NULL, 0, 0}
};

/*
 * Hash table used to hash from (display, colormap, palette, gamma)
 * to ColorTable address.
 */

static Tcl_HashTable imgPhotoColorHash;
static int imgPhotoColorHashInitialized;
#define N_COLOR_HASH	(sizeof(ColorTableId) / sizeof(int))

/*
 * Pointer to the first in the list of known photo image formats.
 */

static Tk_PhotoImageFormat *formatList = NULL;

/*
 * Forward declarations
 */

static int		ImgPhotoCmd _ANSI_ARGS_((ClientData clientData,
			    Tcl_Interp *interp, int argc, char **argv));
static int		ParseSubcommandOptions _ANSI_ARGS_((
			    struct SubcommandOptions *optPtr,
			    Tcl_Interp *interp, int allowedOptions,
			    int *indexPtr, int argc, char **argv));
static void		ImgPhotoCmdDeletedProc _ANSI_ARGS_((
			    ClientData clientData));
static int		ImgPhotoConfigureMaster _ANSI_ARGS_((
			    Tcl_Interp *interp, PhotoMaster *masterPtr,
			    int argc, char **argv, int flags));
static void		ImgPhotoConfigureInstance _ANSI_ARGS_((
			    PhotoInstance *instancePtr));
static void		ImgPhotoSetSize _ANSI_ARGS_((PhotoMaster *masterPtr,
			    int width, int height));
static void		ImgPhotoInstanceSetSize _ANSI_ARGS_((
			    PhotoInstance *instancePtr));
static int		IsValidPalette _ANSI_ARGS_((PhotoInstance *instancePtr,
			    char *palette));
static int		CountBits _ANSI_ARGS_((pixel mask));
static void		GetColorTable _ANSI_ARGS_((PhotoInstance *instancePtr));
static void		FreeColorTable _ANSI_ARGS_((ColorTable *colorPtr));
static void		AllocateColors _ANSI_ARGS_((ColorTable *colorPtr));
static void		DisposeColorTable _ANSI_ARGS_((ClientData clientData));
static void		DisposeInstance _ANSI_ARGS_((ClientData clientData));
static int		ReclaimColors _ANSI_ARGS_((ColorTableId *id,
			    int numColors));
static int		MatchFileFormat _ANSI_ARGS_((Tcl_Interp *interp,
			    Tcl_Channel chan, char *fileName,
			    char *formatString,
			    Tk_PhotoImageFormat **imageFormatPtr,
			    int *widthPtr, int *heightPtr));
static int		MatchStringFormat _ANSI_ARGS_((Tcl_Interp *interp,
			    char *string, char *formatString,
			    Tk_PhotoImageFormat **imageFormatPtr,
			    int *widthPtr, int *heightPtr));
static void		Dither _ANSI_ARGS_((PhotoMaster *masterPtr,
			    int x, int y, int width, int height));
static void		DitherInstance _ANSI_ARGS_((PhotoInstance *instancePtr,
			    int x, int y, int width, int height));

#undef MIN
#define MIN(a, b)	((a) < (b)? (a): (b))
#undef MAX
#define MAX(a, b)	((a) > (b)? (a): (b))

/*
 *----------------------------------------------------------------------
 *
 * Tk_CreatePhotoImageFormat --
 *
 *	This procedure is invoked by an image file handler to register
 *	a new photo image format and the procedures that handle the
 *	new format.  The procedure is typically invoked during
 *	Tcl_AppInit.
 *
 * Results:
 *	None.
 *
 * Side effects:
 *	The new image file format is entered into a table used in the
 *	photo image "read" and "write" subcommands.
 *
 *----------------------------------------------------------------------
 */

void
Tk_CreatePhotoImageFormat(formatPtr)
    Tk_PhotoImageFormat *formatPtr;
				/* Structure describing the format.  All of
				 * the fields except "nextPtr" must be filled
				 * in by caller.  Must not have been passed
				 * to Tk_CreatePhotoImageFormat previously. */
{
    Tk_PhotoImageFormat *copyPtr;

    copyPtr = (Tk_PhotoImageFormat *) ckalloc(sizeof(Tk_PhotoImageFormat));
    *copyPtr = *formatPtr;
    copyPtr->name = (char *) ckalloc((unsigned) (strlen(formatPtr->name) + 1));
    strcpy(copyPtr->name, formatPtr->name);
    copyPtr->nextPtr = formatList;
    formatList = copyPtr;
}

/*
 *----------------------------------------------------------------------
 *
 * ImgPhotoCreate --
 *
 *	This procedure is called by the Tk image code to create
 *	a new photo image.
 *
 * Results:
 *	A standard Tcl result.