[OpenSPARC-T2-SAM] / sam-t2 / devtools / v8plus / man / mann / bitmap.n

'\"
'\" Copyright (c) 1994 The Regents of the University of California.
'\" Copyright (c) 1994-1996 Sun Microsystems, Inc.
'\"
'\" See the file "license.terms" for information on usage and redistribution
'\" of this file, and for a DISCLAIMER OF ALL WARRANTIES.
'\" 
'\" RCS: @(#) $Id: bitmap.n,v 1.2 1998/09/14 18:22:54 stanton Exp $
'\" 
'\" The definitions below are for supplemental macros used in Tcl/Tk
'\" manual entries.
'\"
'\" .AP type name in/out ?indent?
'\"	Start paragraph describing an argument to a library procedure.
'\"	type is type of argument (int, etc.), in/out is either "in", "out",
'\"	or "in/out" to describe whether procedure reads or modifies arg,
'\"	and indent is equivalent to second arg of .IP (shouldn't ever be
'\"	needed;  use .AS below instead)
'\"
'\" .AS ?type? ?name?
'\"	Give maximum sizes of arguments for setting tab stops.  Type and
'\"	name are examples of largest possible arguments that will be passed
'\"	to .AP later.  If args are omitted, default tab stops are used.
'\"
'\" .BS
'\"	Start box enclosure.  From here until next .BE, everything will be
'\"	enclosed in one large box.
'\"
'\" .BE
'\"	End of box enclosure.
'\"
'\" .CS
'\"	Begin code excerpt.
'\"
'\" .CE
'\"	End code excerpt.
'\"
'\" .VS ?version? ?br?
'\"	Begin vertical sidebar, for use in marking newly-changed parts
'\"	of man pages.  The first argument is ignored and used for recording
'\"	the version when the .VS was added, so that the sidebars can be
'\"	found and removed when they reach a certain age.  If another argument
'\"	is present, then a line break is forced before starting the sidebar.
'\"
'\" .VE
'\"	End of vertical sidebar.
'\"
'\" .DS
'\"	Begin an indented unfilled display.
'\"
'\" .DE
'\"	End of indented unfilled display.
'\"
'\" .SO
'\"	Start of list of standard options for a Tk widget.  The
'\"	options follow on successive lines, in four columns separated
'\"	by tabs.
'\"
'\" .SE
'\"	End of list of standard options for a Tk widget.
'\"
'\" .OP cmdName dbName dbClass
'\"	Start of description of a specific option.  cmdName gives the
'\"	option's name as specified in the class command, dbName gives
'\"	the option's name in the option database, and dbClass gives
'\"	the option's class in the option database.
'\"
'\" .UL arg1 arg2
'\"	Print arg1 underlined, then print arg2 normally.
'\"
'\" RCS: @(#) $Id: man.macros,v 1.4 2000/08/25 06:18:32 ericm Exp $
'\"
'\"	# Set up traps and other miscellaneous stuff for Tcl/Tk man pages.
.if t .wh -1.3i ^B
.nr ^l \n(.l
.ad b
'\"	# Start an argument description
.de AP
.ie !"\\$4"" .TP \\$4
.el \{\
.   ie !"\\$2"" .TP \\n()Cu
.   el          .TP 15
.\}
.ta \\n()Au \\n()Bu
.ie !"\\$3"" \{\
\&\\$1	\\fI\\$2\\fP	(\\$3)
.\".b
.\}
.el \{\
.br
.ie !"\\$2"" \{\
\&\\$1	\\fI\\$2\\fP
.\}
.el \{\
\&\\fI\\$1\\fP
.\}
.\}
..
'\"	# define tabbing values for .AP
.de AS
.nr )A 10n
.if !"\\$1"" .nr )A \\w'\\$1'u+3n
.nr )B \\n()Au+15n
.\"
.if !"\\$2"" .nr )B \\w'\\$2'u+\\n()Au+3n
.nr )C \\n()Bu+\\w'(in/out)'u+2n
..
.AS Tcl_Interp Tcl_CreateInterp in/out
'\"	# BS - start boxed text
'\"	# ^y = starting y location
'\"	# ^b = 1
.de BS
.br
.mk ^y
.nr ^b 1u
.if n .nf
.if n .ti 0
.if n \l'\\n(.lu\(ul'
.if n .fi
..
'\"	# BE - end boxed text (draw box now)
.de BE
.nf
.ti 0
.mk ^t
.ie n \l'\\n(^lu\(ul'
.el \{\
.\"	Draw four-sided box normally, but don't draw top of
.\"	box if the box started on an earlier page.
.ie !\\n(^b-1 \{\
\h'-1.5n'\L'|\\n(^yu-1v'\l'\\n(^lu+3n\(ul'\L'\\n(^tu+1v-\\n(^yu'\l'|0u-1.5n\(ul'
.\}
.el \}\
\h'-1.5n'\L'|\\n(^yu-1v'\h'\\n(^lu+3n'\L'\\n(^tu+1v-\\n(^yu'\l'|0u-1.5n\(ul'
.\}
.\}
.fi
.br
.nr ^b 0
..
'\"	# VS - start vertical sidebar
'\"	# ^Y = starting y location
'\"	# ^v = 1 (for troff;  for nroff this doesn't matter)
.de VS
.if !"\\$2"" .br
.mk ^Y
.ie n 'mc \s12\(br\s0
.el .nr ^v 1u
..
'\"	# VE - end of vertical sidebar
.de VE
.ie n 'mc
.el \{\
.ev 2
.nf
.ti 0
.mk ^t
\h'|\\n(^lu+3n'\L'|\\n(^Yu-1v\(bv'\v'\\n(^tu+1v-\\n(^Yu'\h'-|\\n(^lu+3n'
.sp -1
.fi
.ev
.\}
.nr ^v 0
..
'\"	# Special macro to handle page bottom:  finish off current
'\"	# box/sidebar if in box/sidebar mode, then invoked standard
'\"	# page bottom macro.
.de ^B
.ev 2
'ti 0
'nf
.mk ^t
.if \\n(^b \{\
.\"	Draw three-sided box if this is the box's first page,
.\"	draw two sides but no top otherwise.
.ie !\\n(^b-1 \h'-1.5n'\L'|\\n(^yu-1v'\l'\\n(^lu+3n\(ul'\L'\\n(^tu+1v-\\n(^yu'\h'|0u'\c
.el \h'-1.5n'\L'|\\n(^yu-1v'\h'\\n(^lu+3n'\L'\\n(^tu+1v-\\n(^yu'\h'|0u'\c
.\}
.if \\n(^v \{\
.nr ^x \\n(^tu+1v-\\n(^Yu
\kx\h'-\\nxu'\h'|\\n(^lu+3n'\ky\L'-\\n(^xu'\v'\\n(^xu'\h'|0u'\c
.\}
.bp
'fi
.ev
.if \\n(^b \{\
.mk ^y
.nr ^b 2
.\}
.if \\n(^v \{\
.mk ^Y
.\}
..
'\"	# DS - begin display
.de DS
.RS
.nf
.sp
..
'\"	# DE - end display
.de DE
.fi
.RE
.sp
..
'\"	# SO - start of list of standard options
.de SO
.SH "STANDARD OPTIONS"
.LP
.nf
.ta 5.5c 11c
.ft B
..
'\"	# SE - end of list of standard options
.de SE
.fi
.ft R
.LP
See the \\fBoptions\\fR manual entry for details on the standard options.
..
'\"	# OP - start of full description for a single option
.de OP
.LP
.nf
.ta 4c
Command-Line Name:	\\fB\\$1\\fR
Database Name:	\\fB\\$2\\fR
Database Class:	\\fB\\$3\\fR
.fi
.IP
..
'\"	# CS - begin code excerpt
.de CS
.RS
.nf
.ta .25i .5i .75i 1i
..
'\"	# CE - end code excerpt
.de CE
.fi
.RE
..
.de UL
\\$1\l'|0\(ul'\\$2
..
.TH bitmap n 4.0 Tk "Tk Built-In Commands"
.BS
'\" Note:  do not modify the .SH NAME line immediately below!
.SH NAME
bitmap \- Images that display two colors
.SH SYNOPSIS
\fBimage create bitmap \fR?\fIname\fR? ?\fIoptions\fR?
.BE

.SH DESCRIPTION
.PP
A bitmap is an image whose pixels can display either of two colors
or be transparent.
A bitmap image is defined by four things:  a background color,
a foreground color, and two bitmaps, called the \fIsource\fR
and the \fImask\fR.
Each of the bitmaps specifies 0/1 values for a rectangular
array of pixels, and the two bitmaps must have the same
dimensions.
For pixels where the mask is zero, the image displays nothing,
producing a transparent effect.
For other pixels, the image displays the foreground color if
the source data is one and the background color if the source
data is zero.

.SH "CREATING BITMAPS"
.PP
Like all images, bitmaps are created using the \fBimage create\fR
command.
Bitmaps support the following \fIoptions\fR:
.TP
\fB\-background \fIcolor\fR
Specifies a background color for the image in any of the standard
ways accepted by Tk.  If this option is set to an empty string
then the background pixels will be transparent.  This effect
is achieved by using the source bitmap as the mask bitmap, ignoring
any \fB\-maskdata\fR or \fB\-maskfile\fR options.
.TP
\fB\-data \fIstring\fR
Specifies the contents of the source bitmap as a string.
The string must adhere to X11 bitmap format (e.g., as generated
by the \fBbitmap\fR program).
If both the \fB\-data\fR and \fB\-file\fR options are specified,
the \fB\-data\fR option takes precedence.
.TP
\fB\-file \fIname\fR
\fIname\fR gives the name of a file whose contents define the
source bitmap.
The file must adhere to X11 bitmap format (e.g., as generated
by the \fBbitmap\fR program).
.TP
\fB\-foreground \fIcolor\fR
Specifies a foreground color for the image in any of the standard
ways accepted by Tk.
.TP
\fB\-maskdata \fIstring\fR
Specifies the contents of the mask as a string.
The string must adhere to X11 bitmap format (e.g., as generated
by the \fBbitmap\fR program).
If both the \fB\-maskdata\fR and \fB\-maskfile\fR options are specified,
the \fB\-maskdata\fR option takes precedence.
.TP
\fB\-maskfile \fIname\fR
\fIname\fR gives the name of a file whose contents define the
mask.
The file must adhere to X11 bitmap format (e.g., as generated
by the \fBbitmap\fR program).

.SH "IMAGE COMMAND"
.PP
When a bitmap image is created, Tk also creates a new command
whose name is the same as the image.
This command may be used to invoke various operations
on the image.
It has the following general form:
.CS
\fIimageName option \fR?\fIarg arg ...\fR?
.CE
\fIOption\fR and the \fIarg\fRs
determine the exact behavior of the command.  The following
commands are possible for bitmap images:
.TP
\fIimageName \fBcget\fR \fIoption\fR
Returns the current value of the configuration option given
by \fIoption\fR.
\fIOption\fR may have any of the values accepted by the
\fBimage create bitmap\fR command.
.TP
\fIimageName \fBconfigure\fR ?\fIoption\fR? ?\fIvalue option value ...\fR?
Query or modify the configuration options for the image.
If no \fIoption\fR is specified, returns a list describing all of
the available options for \fIimageName\fR (see \fBTk_ConfigureInfo\fR for
information on the format of this list).  If \fIoption\fR is specified
with no \fIvalue\fR, then the command returns a list describing the
one named option (this list will be identical to the corresponding
sublist of the value returned if no \fIoption\fR is specified).  If
one or more \fIoption\-value\fR pairs are specified, then the command
modifies the given option(s) to have the given value(s);  in
this case the command returns an empty string.
\fIOption\fR may have any of the values accepted by the
\fBimage create bitmap\fR command.

.SH KEYWORDS
bitmap, image
Commit	Line	Data
920dae64 AT	1	'\"
	2	'\" Copyright (c) 1994 The Regents of the University of California.
	3	'\" Copyright (c) 1994-1996 Sun Microsystems, Inc.
	4	'\"
	5	'\" See the file "license.terms" for information on usage and redistribution
	6	'\" of this file, and for a DISCLAIMER OF ALL WARRANTIES.
	7	'\"
	8	'\" RCS: @(#) $Id: bitmap.n,v 1.2 1998/09/14 18:22:54 stanton Exp $
	9	'\"
	10	'\" The definitions below are for supplemental macros used in Tcl/Tk
	11	'\" manual entries.
	12	'\"
	13	'\" .AP type name in/out ?indent?
	14	'\" Start paragraph describing an argument to a library procedure.
	15	'\" type is type of argument (int, etc.), in/out is either "in", "out",
	16	'\" or "in/out" to describe whether procedure reads or modifies arg,
	17	'\" and indent is equivalent to second arg of .IP (shouldn't ever be
	18	'\" needed; use .AS below instead)
	19	'\"
	20	'\" .AS ?type? ?name?
	21	'\" Give maximum sizes of arguments for setting tab stops. Type and
	22	'\" name are examples of largest possible arguments that will be passed
	23	'\" to .AP later. If args are omitted, default tab stops are used.
	24	'\"
	25	'\" .BS
	26	'\" Start box enclosure. From here until next .BE, everything will be
	27	'\" enclosed in one large box.
	28	'\"
	29	'\" .BE
	30	'\" End of box enclosure.
	31	'\"
	32	'\" .CS
	33	'\" Begin code excerpt.
	34	'\"
	35	'\" .CE
	36	'\" End code excerpt.
	37	'\"
	38	'\" .VS ?version? ?br?
	39	'\" Begin vertical sidebar, for use in marking newly-changed parts
	40	'\" of man pages. The first argument is ignored and used for recording
	41	'\" the version when the .VS was added, so that the sidebars can be
	42	'\" found and removed when they reach a certain age. If another argument
	43	'\" is present, then a line break is forced before starting the sidebar.
	44	'\"
	45	'\" .VE
	46	'\" End of vertical sidebar.
	47	'\"
	48	'\" .DS
	49	'\" Begin an indented unfilled display.
	50	'\"
	51	'\" .DE
	52	'\" End of indented unfilled display.
	53	'\"
	54	'\" .SO
	55	'\" Start of list of standard options for a Tk widget. The
	56	'\" options follow on successive lines, in four columns separated
	57	'\" by tabs.
	58	'\"
	59	'\" .SE
	60	'\" End of list of standard options for a Tk widget.
	61	'\"
	62	'\" .OP cmdName dbName dbClass
	63	'\" Start of description of a specific option. cmdName gives the
	64	'\" option's name as specified in the class command, dbName gives
65	'\" the option's name in the option database, and dbClass gives
66	'\" the option's class in the option database.
67	'\"
68	'\" .UL arg1 arg2
69	'\" Print arg1 underlined, then print arg2 normally.
70	'\"
71	'\" RCS: @(#) $Id: man.macros,v 1.4 2000/08/25 06:18:32 ericm Exp $
72	'\"
73	'\" # Set up traps and other miscellaneous stuff for Tcl/Tk man pages.
74	.if t .wh -1.3i ^B
75	.nr ^l \n(.l
76	.ad b
77	'\" # Start an argument description
78	.de AP
79	.ie !"\\$4"" .TP \\$4
80	.el \{\
81	. ie !"\\$2"" .TP \\n()Cu
82	. el .TP 15
83	.\}
84	.ta \\n()Au \\n()Bu
85	.ie !"\\$3"" \{\
86	\&\\$1 \\fI\\$2\\fP (\\$3)
87	.\".b
88	.\}
89	.el \{\
90	.br
91	.ie !"\\$2"" \{\
92	\&\\$1 \\fI\\$2\\fP
93	.\}
94	.el \{\
95	\&\\fI\\$1\\fP
96	.\}
97	.\}
98	..
99	'\" # define tabbing values for .AP
100	.de AS
101	.nr )A 10n
102	.if !"\\$1"" .nr )A \\w'\\$1'u+3n
103	.nr )B \\n()Au+15n
104	.\"
105	.if !"\\$2"" .nr )B \\w'\\$2'u+\\n()Au+3n
106	.nr )C \\n()Bu+\\w'(in/out)'u+2n
107	..
108	.AS Tcl_Interp Tcl_CreateInterp in/out
109	'\" # BS - start boxed text
110	'\" # ^y = starting y location
111	'\" # ^b = 1
112	.de BS
113	.br
114	.mk ^y
115	.nr ^b 1u
116	.if n .nf
117	.if n .ti 0
118	.if n \l'\\n(.lu\(ul'
119	.if n .fi
120	..
121	'\" # BE - end boxed text (draw box now)
122	.de BE
123	.nf
124	.ti 0
125	.mk ^t
126	.ie n \l'\\n(^lu\(ul'
127	.el \{\
128	.\" Draw four-sided box normally, but don't draw top of
129	.\" box if the box started on an earlier page.
130	.ie !\\n(^b-1 \{\
131	\h'-1.5n'\L'\|\\n(^yu-1v'\l'\\n(^lu+3n\(ul'\L'\\n(^tu+1v-\\n(^yu'\l'\|0u-1.5n\(ul'
132	.\}
133	.el \}\
134	\h'-1.5n'\L'\|\\n(^yu-1v'\h'\\n(^lu+3n'\L'\\n(^tu+1v-\\n(^yu'\l'\|0u-1.5n\(ul'
135	.\}
136	.\}
137	.fi
138	.br
139	.nr ^b 0
140	..
141	'\" # VS - start vertical sidebar
142	'\" # ^Y = starting y location
143	'\" # ^v = 1 (for troff; for nroff this doesn't matter)
144	.de VS
145	.if !"\\$2"" .br
146	.mk ^Y
147	.ie n 'mc \s12\(br\s0
148	.el .nr ^v 1u
149	..
150	'\" # VE - end of vertical sidebar
151	.de VE
152	.ie n 'mc
153	.el \{\
154	.ev 2
155	.nf
156	.ti 0
157	.mk ^t
158	\h'\|\\n(^lu+3n'\L'\|\\n(^Yu-1v\(bv'\v'\\n(^tu+1v-\\n(^Yu'\h'-\|\\n(^lu+3n'
159	.sp -1
160	.fi
161	.ev
162	.\}
163	.nr ^v 0
164	..
165	'\" # Special macro to handle page bottom: finish off current
166	'\" # box/sidebar if in box/sidebar mode, then invoked standard
167	'\" # page bottom macro.
168	.de ^B
169	.ev 2
170	'ti 0
171	'nf
172	.mk ^t
173	.if \\n(^b \{\
174	.\" Draw three-sided box if this is the box's first page,
175	.\" draw two sides but no top otherwise.
176	.ie !\\n(^b-1 \h'-1.5n'\L'\|\\n(^yu-1v'\l'\\n(^lu+3n\(ul'\L'\\n(^tu+1v-\\n(^yu'\h'\|0u'\c
177	.el \h'-1.5n'\L'\|\\n(^yu-1v'\h'\\n(^lu+3n'\L'\\n(^tu+1v-\\n(^yu'\h'\|0u'\c
178	.\}
179	.if \\n(^v \{\
180	.nr ^x \\n(^tu+1v-\\n(^Yu
181	\kx\h'-\\nxu'\h'\|\\n(^lu+3n'\ky\L'-\\n(^xu'\v'\\n(^xu'\h'\|0u'\c
182	.\}
183	.bp
184	'fi
185	.ev
186	.if \\n(^b \{\
187	.mk ^y
188	.nr ^b 2
189	.\}
190	.if \\n(^v \{\
191	.mk ^Y
192	.\}
193	..
194	'\" # DS - begin display
195	.de DS
196	.RS
197	.nf
198	.sp
199	..
200	'\" # DE - end display
201	.de DE
202	.fi
203	.RE
204	.sp
205	..
206	'\" # SO - start of list of standard options
207	.de SO
208	.SH "STANDARD OPTIONS"
209	.LP
210	.nf
211	.ta 5.5c 11c
212	.ft B
213	..
214	'\" # SE - end of list of standard options
215	.de SE
216	.fi
217	.ft R
218	.LP
219	See the \\fBoptions\\fR manual entry for details on the standard options.
220	..
221	'\" # OP - start of full description for a single option
222	.de OP
223	.LP
224	.nf
225	.ta 4c
226	Command-Line Name: \\fB\\$1\\fR
227	Database Name: \\fB\\$2\\fR
228	Database Class: \\fB\\$3\\fR
229	.fi
230	.IP
231	..
232	'\" # CS - begin code excerpt
233	.de CS
234	.RS
235	.nf
236	.ta .25i .5i .75i 1i
237	..
238	'\" # CE - end code excerpt
239	.de CE
240	.fi
241	.RE
242	..
243	.de UL
244	\\$1\l'\|0\(ul'\\$2
245	..
246	.TH bitmap n 4.0 Tk "Tk Built-In Commands"
247	.BS
248	'\" Note: do not modify the .SH NAME line immediately below!
249	.SH NAME
250	bitmap \- Images that display two colors
251	.SH SYNOPSIS
252	\fBimage create bitmap \fR?\fIname\fR? ?\fIoptions\fR?
253	.BE
254
255	.SH DESCRIPTION
256	.PP
257	A bitmap is an image whose pixels can display either of two colors
258	or be transparent.
259	A bitmap image is defined by four things: a background color,
260	a foreground color, and two bitmaps, called the \fIsource\fR
261	and the \fImask\fR.
262	Each of the bitmaps specifies 0/1 values for a rectangular
263	array of pixels, and the two bitmaps must have the same
264	dimensions.
265	For pixels where the mask is zero, the image displays nothing,
266	producing a transparent effect.
267	For other pixels, the image displays the foreground color if
268	the source data is one and the background color if the source
269	data is zero.
270
271	.SH "CREATING BITMAPS"
272	.PP
273	Like all images, bitmaps are created using the \fBimage create\fR
274	command.
275	Bitmaps support the following \fIoptions\fR:
276	.TP
277	\fB\-background \fIcolor\fR
278	Specifies a background color for the image in any of the standard
279	ways accepted by Tk. If this option is set to an empty string
280	then the background pixels will be transparent. This effect
281	is achieved by using the source bitmap as the mask bitmap, ignoring
282	any \fB\-maskdata\fR or \fB\-maskfile\fR options.
283	.TP
284	\fB\-data \fIstring\fR
285	Specifies the contents of the source bitmap as a string.
286	The string must adhere to X11 bitmap format (e.g., as generated
287	by the \fBbitmap\fR program).
288	If both the \fB\-data\fR and \fB\-file\fR options are specified,
289	the \fB\-data\fR option takes precedence.
290	.TP
291	\fB\-file \fIname\fR
292	\fIname\fR gives the name of a file whose contents define the
293	source bitmap.
294	The file must adhere to X11 bitmap format (e.g., as generated
295	by the \fBbitmap\fR program).
296	.TP
297	\fB\-foreground \fIcolor\fR
298	Specifies a foreground color for the image in any of the standard
299	ways accepted by Tk.
300	.TP
301	\fB\-maskdata \fIstring\fR
302	Specifies the contents of the mask as a string.
303	The string must adhere to X11 bitmap format (e.g., as generated
304	by the \fBbitmap\fR program).
305	If both the \fB\-maskdata\fR and \fB\-maskfile\fR options are specified,
306	the \fB\-maskdata\fR option takes precedence.
307	.TP
308	\fB\-maskfile \fIname\fR
309	\fIname\fR gives the name of a file whose contents define the
310	mask.
311	The file must adhere to X11 bitmap format (e.g., as generated
312	by the \fBbitmap\fR program).
313
314	.SH "IMAGE COMMAND"
315	.PP
316	When a bitmap image is created, Tk also creates a new command
317	whose name is the same as the image.
318	This command may be used to invoke various operations
319	on the image.
320	It has the following general form:
321	.CS
322	\fIimageName option \fR?\fIarg arg ...\fR?
323	.CE
324	\fIOption\fR and the \fIarg\fRs
325	determine the exact behavior of the command. The following
326	commands are possible for bitmap images:
327	.TP
328	\fIimageName \fBcget\fR \fIoption\fR
329	Returns the current value of the configuration option given
330	by \fIoption\fR.
331	\fIOption\fR may have any of the values accepted by the
332	\fBimage create bitmap\fR command.
333	.TP
334	\fIimageName \fBconfigure\fR ?\fIoption\fR? ?\fIvalue option value ...\fR?
335	Query or modify the configuration options for the image.
336	If no \fIoption\fR is specified, returns a list describing all of
337	the available options for \fIimageName\fR (see \fBTk_ConfigureInfo\fR for
338	information on the format of this list). If \fIoption\fR is specified
339	with no \fIvalue\fR, then the command returns a list describing the
340	one named option (this list will be identical to the corresponding
341	sublist of the value returned if no \fIoption\fR is specified). If
342	one or more \fIoption\-value\fR pairs are specified, then the command
343	modifies the given option(s) to have the given value(s); in
344	this case the command returns an empty string.
345	\fIOption\fR may have any of the values accepted by the
346	\fBimage create bitmap\fR command.
347
348	.SH KEYWORDS
349	bitmap, image