W3 Image 2.0 Manual
Contents
1. imageobj StreamImage Response BMP 24 oe V You can solve this by temporarily not streaming the image and instead saving the image directly to disk SaveImage Naturally you must then run the image asp file directly since there is no streaming For further information about error handling please see nr 2 4 of the ASP example files that come with the installation of w3 Image These files describe how to generate images displaying the error messages If you need to contact our support please do not send these generated images Instead post a request at our helpdesk and send the error message with your request Streaming to an ADODB Stream This code shows an example of streaming the image to an ADODB Stream LANGUAGE VBSCRIPT gt o oo set olmage Server CreateObject W3Image Image oImage LoadImage Server Mappath yay_train jpg oImage Flip 2 flip image so we see something happens to it Set objStream Server CreateObject ADODB Stream http www dimac net 18 w3 Image 2 0 Manual objStream Type 1 read only objStream Open open stream olmage StreamImage objStream GIF 8 grayscale write to stream Set oImage Nothing kill image object objStream position 0 rewind stream write content to browser response binarywrite objStream Read close and dispose of stream object objStream Close Set objStream Nothing oe gt Why should one want to2. The function continues to search the image until the palette is filled or until the function has reached the end of the image http www dimac net 19 w3 Image 2 0 Manual Example imageobj Savelmage test png PNG 4 Positive Good to use if the image contains fewer colors than palette entries The colors in the palette matches exactly the value in the image Negative Pretty slow to generate GreyScale Palette This function generates a greyscale palette Each RGB value is presented in the same matter for the red green and blue intensity value The function splits up the color range in equally divided parts as shown below BER ERR BRR ERR Ree BERR ERE eee eee BER ERR eee s Ree EER Eee eee eee BER EERE Eee BER ERR RE eee eee EER EERE EERE BERR RRR EERE EERE Figure 8 A greyscale palette for a 8 bit image Example imageobj StreamImage Response BMP 8 greyscale or same imageobj StreamImage Response BMP 8 1 Positive Fast to generate Negative No colors Rainbow Palette http www dimac net w3 Image 2 0 Manual Green Blue Number Red Calar bisce 0 128 128 D 128 128 Figure 9 The first eight palette entries in a 4 bit image using the rainbow function O E Note that the black color 0x00000 value is always presented one time and at the first color entry Depending on the number of palette entries each
3. Image system are persistable that is they can be directly loaded or saved to a stream using the IPersistStream interface methods This is useful when restoring the state of an object after an undetermined time For example imagine a tool in which the user could continue the drawings of an image as it was before with the selected pen brush font and the data The system has been optimised to stream the data to the client machine by best performance This is done by direct accessing the Response object and the write mechanisms to the client machines Another advantage by using this method is that the system is now capable to define the image data type before sending it to the client content type The images created with w3 Image are generated on a server and shown at the client as a picture Therefore the images can be displayed on all client platforms and browsers provided that the image format is supported by the browser w3 Image offers several ways of defining colors The management has been adapted to suit the web environment as the colors can be described in a hexadecimal form or in a web color form http www dimac net 5 w3 Image 2 0 Manual w3 Image can create images with numerous palette algorithms Depending on the demands of the performance or the importance of the color information in the output data different algorithms can be selected Who should read this manual This manual is intended for the users of Dimac
4. s w3 Image The users should have knowledge in basic programming JScript and or VB Script How this manual is organized Chapter 1 Objects Chapter 1 introduces you to the objects used in w3 Image images pens brushes fonts colors and their different properties Chapter 2 Operations Chapter 2 lists all operations you can perform with the different objects For example draw a line with a pen fill a circle with a color or enter a text Chapter 2 also describes the image palettes used in w3 Image Chapter 3 Image Formats Chapter 3 informs you about the image formats supported by w3 Image Chapter 4 Transparency Chapter 4 tells you about the behaviour of transparency in w3 Image What s new 2 0 w3Image is now fully capable of loading and streaming any of the supported image formats This by using the LoadImageFromStream and the StreamImage method Support of the WBMP format in all import and export methods WBMP files is very useful when creating mobile applications and scripts Support of loading images from an url location Transformation methods are added such as GreyScale Threshold and invertion of images using the Negative method w3Image is extended with lighting operations such as Brightness Contrast and manipulation of individual intensity by using the ShiftRGB method Version property is added to receive the version string of the dll file The RotateCenter is an extended version of the rotate m
5. Palettes essetis nie EOS puRE Dti cuu dai Co et wiv ecient es A REEE 19 JPG COBIDEGSSIOO neas aue aaan aiee DLE e bendi uoo au ta ee 22 Chapter 3 Image Formatsion ae ERR IDE Se RR FER Sn ns eaa EEE EE AEE EREE EE iG 22 BMP e vegeeees 22 c 23 latc ient aaa n aE Eaa E AE E aE EE ESEE 23 p Mec E E E E E E E 25 TRE C RE 25 MA E E ben toe Sacre peed aeaeanciatee ta beualeadedieuaee 25 j p 26 WBMP M 26 Ch ptet 4 Transparent y cuota recent eni quta cit a ca Padi arda iata 27 B ckground dO ocasion eb M E EDD E d cs utem EE Mes 27 Background Color D 27 http www dimac net 3 w3 Image 2 0 Manual Copyright We have done our best to ensure that the information in this manual is both accurate and useful however please be aware that errors may exist and that Dimac Development Duplo AB hereafter referred to as Duplo does not give any guarantees concerning the accuracy of the information here or in the use to which it may be put Duplo may have patents and or pending patent applications covering subject matter in this document Copyright 2004 Duplo AB All rights reserved This document may only be reproduced in whole or part copied photocopied trans
6. The height of the image object s surface in pixels Width The width of the image object s surface in pixels Import LoadImage Load an image from a disk and create a surface for the image Please turn to Chapter 3 Image Formats for information on which image formats w3 Image supports LoadImageFromStream Loads an image from a IStream object for example adodb stream Loading from ADODB Stream requires MDAC2 6 or greater LoadImageFromURL Loads image from an URL f x LoadImageFromURL http www dimac net logo jpg http www dimac net 17 w3 Image 2 0 Manual Export Savelmage Save the surface of an image to a file StreamImage Stream the surface of an image to an object that supports Stream or IResponse Examples of streaming Streaming image data to Response object When streaming image data to the Response object you can not do any response messages in the script generating the image The following example tries to return a message via the Response object in the image asp file This can not be done since the text message will interfere with the data generated by w3 Image File index html lt html gt lt head gt lt head gt lt body gt lt img name w3image id w3image src image asp gt lt body gt lt html gt File image asp LANGUAGE VBSCRIPT gt oe oe Set imageobj Server CreateObject w3image image img CretateEmptySurface 100 100 Response Write Test Not allowed
7. alculate the position for the font top and left 8 Perform the drawing of the text 9 Stream the image to the client that is display the result on the computer screen 1 imageobj CreateEmptySurface 1 1 2 Set fontobj imageobj CreateFont Tahoma 60 0 normal 0 amp HO0000000 amp false false true imageobj SetFont fontobj 3 text w3 Image is the answer 4 width imageobj GetTextWidth text height imageobj GetTextHeight text 5 imageobj LoadImage C Projects www w3Image Demo images dimac jpg Important Reselect the font all data is erased when creating a new surface 6 imageobj SetFont fontobj 7 top imageobj height height 2 If top 0 then top 0 End If left imageobj width width 2 If left lt 0 then left 0 End If 8 imageobj DrawText text left top 9 imageobj StreamImage Response JPG 24 Kerning GetFirstKernChar Get the first kerning charachter from a pair at a specified index GetSecondKernChar Get the second kerning charachter from a pair at a specified index GetKernAmount Get the kerning value from a pair of kerning charachters http www dimac net 15 w3 Image 2 0 Manual KerningPairsCount Get the number of kerning charachter pairs from a font object Blit and Copy StretchBlt Copy a part of a surface to another part within the same image object StretchBItExt Copy a part of a surface to another part within another image ob
8. ame To create a color object using a web color value Create a color object with the RGB value of 2 10 and 245 by describing each value as a hexadecimal number Set colorobj imageobj CreateColor 020AF5 To receive a web color Receive the web color used by the color object Receive the web color value webcolor colorobj webcolor Response Write webcolor An example of the output could be 34A510 To change a web color Change the web color Red is changed to the RGB value of 204 255 and 187 colorobj webcolor CCFFBB Web Color Name Web safe colors Another method to describe a color value is by defining it as a color text Then the user doesn t have to know the actual RGB value of a color definition As there are over 16 millions different combinations of a color value it could be quite difficult to remember the exact color value Therefore the most common used web colors are collected in color set where each value is described as a color text The color set in w3 Image contains 139 different colors To create a color object using a web color name Create a color object using a web color name and receive its blue intensity value Set colorobj imageobj CreateColor antiquewhite blue colorobj blue Chapter 2 Operations Simple Drawing DrawLine Draw a line between two points with a chosen pen http www dimac net 13 w3 Image 2 0 Manual DrawEllipse Draw an ellipse with a chosen pen
9. and fill it with a chosen brush DrawRect Draw a rectangle with a chosen pen and fill it with a chosen brush FloodFill Fill a surface with a chosen brush The co ordinate system in w3 Image The following illustration shows the co ordinate system in w3 Image with a filled rectangle 0 0 X Top Bottom y Left Right Figure 2 A blue rectangle positioned in the co ordinate system Pixel SetPixel Set a chosen color for a separate pixel on a specified position GetPixel Get the value of a pixel on a specified position Text GetTextHeight Get the height of a text GetTextWidth Get the width of a text The height and width of a text The text height is the height of the selected font The text width is the width of the surface the text occupies Text Height Text Height Text Width Text Width Figure 3 and 4 The illustrations show the text height and width of two words written in the same font http www dimac net 14 w3 Image 2 0 Manual DrawText Render a text with a chosen font Center a text 1 In order to perform any font operation you have to create an empty surface 1x1 pixel is enough 2 Then create and select the font you want to use 3 Define the text to be centered 4 Receive the width and the height of the text 5 Load the image in which you want to center the text 6 Select the font again since creating a new surface removes previous set objects When loading an image a new surface is created 7 C
10. ate and select a font OD JOC je vacnacciaciniaeaetennandanenacecednsasduaspanvencoeaaaniadextuedeceareee 12 bosse supe 12 RGB s Rud NRI TO D OLLI ET 12 To create a color object using BUB e RASEN EE UR VERE RU AC Id iR rev idqqs 12 To receive the intensity color of each RGB value eeeeeneee 12 To change an individual RGB value sess 12 Web Color RGB S uii P 13 To create a color object using a web color value eeeeeeeeeeeee 13 ber hcec 13 Terehanpe n web CO IOR sc o abeeius cat uic pb ui Due adus Mee ub baud bul uA Uu udi ant I3 Web Color Name Web safe COLOLs c cccccccecsssessssececececeesessnsececeeeceeeesesssaeeeseceens 13 To create a color object using a web color name eeeeeeeeereee 13 Chapter 2 CCR aeseseiesnaskteo Use pram da Srt toma t shes taa t eU esia ppm aute erac Pe esee due 13 Simple Drawing de 13 Pireler E E E E E a o 14 E M aad 14 j MCT pM 15 Bitand Copy SP 16 Transformaatio MOM 16 Image Informatio ameet dI brote uu irrita daga I reboot Des bur apoio A wed D Ur Sepe ia 17 Opon eC XT ET 17 jq P 18 http www dimac net 2 w3 Image 2 0 Manual Image
11. color block 7 entries is added continuously after the black color The rainbow palette below is the result of the algorithm above used by an 8 bit image BREE RRR BREE EERE EERE EERE EEE ERE Eee LE ET aalala a BERBERS RE RERE EEE LE BREE RRR eee LTTE NNN NNN LEE LTT TT LTTE NENNEN CEE ENNE EE LTTE ooo 6EE EEE TT TTT Figure 10 A rainbow palette for an 8 bit image Example imageobj Savelmage c test bmp BMP 4 rainbow ons imageobj StreamImage Response BMP 4 2 Positive Fast to generate Negative The steps between the colors are large It uses colors which are not necessarily needed Nearest Color Palette http www dimac net 21 w3 Image 2 0 Manual The nearest color function loops through the pixel values in the image to select the nearest given neighbor Here the algorithm has split the pixel to a valid RGB value and rounded off the blue intensity from 20 to its nearest neighbor 16 l Ag 4n U if 4 20 r py 71 eps ot i oa Figure 11 A round off value Hlue intensity color Example imageobj StreamImage Response BMP 8 nearest QE imageobj StreamImage Response BMP 8 3 Positive Good when using many colors Negative Slow to generate JPG Compression To accomplish different qualities of the JPG image when exporting the image the compression rate mu
12. cript and that 0x445566 specifies a hexadecimal value in Java Script There are different ways to indicate the value in VB Script but we recommend the above mentioned example Working with Pens Pens are used to perform simple drawing operations such as DrawLine and DrawRect see section Simple Drawing in Chapter 2 Operations To create and select a pen object When creating a pen object it is possible to define three types of attributes style width and color Create a red solid pen with the width of two pixels Set penobj imageobj CreatePen solid 2 amp HOOFFO0000 amp Select the created pen imageobj SetPen penobj Perform the drawing operation with the selected pen imageobj DrawLine 10 10 100 100 http www dimac net 10 w3 Image 2 0 Manual Styles of pens There are solid and none solid pens A none solid pen is a dashed and or dotted line The width of a non solid pen is 1 pixel A pen with a width size larger than 1 pixel can not be non solid The width of a solid pen is 1 pixel at the minimum When a non solid drawing operation is used it is important to define the right background properties in order define the gap color and the transparency The three illustrations show a red pen on a blue image The background color is set to yellow I N oJ Number 1 shows the drawing of a solid pen Number 2 and 3 show a non solid pen In number 2 the background mode is set to opaque In number 3 th
13. do the above when you can stream to the Response object you ask ADODB streams are more flexible and the above is just an example Instead of writing the binary stream to the response object you could put it into a recordset field instead obj RS MyBlobField appendChunk objStream Read Support of image formats w3 image supports the functionality of streaming the image data of the following formats BMP Bitmap JPG Joint Photographic Experts Group PNG Portable Network Graphic GIF Graphics Interchange Format TIFF Tagged Image File Format TGA or TARGA Truevision Advanced Raster Graphics Adapter ICO Windows Icon WBMP Wireless Bitmap Note that some web browsers can not display all image formats correctly Image Palettes When using images with color depth less or equal to 8 bit pixel or palette entries less or equal to 255 a palette is needed w3 Image uses the palette functions when working with BMP PNG GIF TIFF TGA and ICO files but not JPG files w3 Image supports four different palette algorithms or functions First Found Greyscale Rainbow Nearest Color Note that the First Found algorithm is used as default when none is specified First Found Color Palette default This palette function starts to search from the bottom of an image for the first found color values If a color value in the image doesn t exist in the palette it is automatically added to the palette
14. e background mode is set to transparent Working with Brushes Brushes are generally used to paint the interior of polygons and ellipses w3 Image supports solid brushes which paints with a specified solid color To create and select a brush object The example shows how to create and select a solid brush and perform a drawing operation Create a brush object Set brushobj imageobj CreateSolidBrush amp HOOA3F403 amp Select the brush imageobj SetBrush brushobj Perform the drawing operation with the selected brush imageobj FloodFill 10 10 amp HOOABCDEF amp Working with Fonts The font object is used to describe and or to receive information about a specific font The most important properties of a font are the typeface the style and the size To create and use a font object the font needs to be installed on the computer server http www dimac net 11 w3 Image 2 0 Manual To create and select a font object With the following example you create a font with the typeface Tahoma using a normal style and a height of 48 Create a font object Set fontobj imageobj CreateFont Tahoma 48 0 normal 0 amp HOOOOFFO0 amp false false false Select the font imageobj SetFont fontobj Perform the drawing operation with the selected font imageobj DrawText Dimac 15 20 Working with Colors The benefit by using the color object compared to normal color definition hexadecimal form are the powerfu
15. ers greater color support and better compression gamma correction for brightness control across platforms better support for transparency and a better method for displaying progressive images When saving an image to the PNG format add the file extension png to the end of its file name Example imageobj LoadlImage example png Stream a 4 bit PNG image use default palette imageobj StreamImage Response PNG 4 w3 Image supports 1 4 8 24 and 32 bit files If 24 bit color depth is defined http www dimac net 23 w3 Image 2 0 Manual the image will be saved streamed as a 32 bit image Positive Generates small images when using painted images Negative Large files if the amount of colors is high slow to generate http www dimac net 24 w3 Image 2 0 Manual GIF The Graphics Interchange Format GIF was originally developed by CompusServe in 1987 It is one of the most popular file formats for web graphics and for exchanging graphics files between computers It is most commonly used for bitmap images composed of line drawings or blocks of a few distinct colors The GIF format supports 8 bits of color information or less It also support transparency and animation but animation is not supported by w3 Image When saving an image to the GIF format add the file extension gif to the end of its file name Example imageobj LoadlImage example gif Stream a 4 bit GIF image use default palette imageob
16. ethod The method rotates the image at the center of the picture and resizes the image if neccessary The method is very fast and using different types of interpolation methods http www dimac net 6 w3 Image 2 0 Manual w3Image has rebuilt the import functions to inherit the transparency of the loaded image Note This may affect your earlier code If you ve previously loaded jpegs and applied text or other items to them transparently you may need to set image bkmode 1 manually after loading them The export of 32 bit PNG images is changed to use the alpha channel in a more proper way 1 3 When using the method StretchB tExt you can now quickly perform the combination of alpha and transparent blit since we have added the operation alphatransparent The steps of the operations are cut down to one single step Get low level access to the memory useful e g when building your own filters with Lock Memory UnlockMemory List all available fonts on the host machine with GetFontFamiliesName getFontFamiliesCount 1 1 Support for NT4 and IIS4 Four new image formats are supported by w3 Image GIF TIFF TGA and ICO Please see Chapter 3 for further information Support for transparency when generating GIF and PNG images Please see Chapter 4 for further information Extended algorithms for transformation operations Stretch Scale and Rotate Please see the Reference Manual for further information In
17. in TGA format The format is used to support image capturing and is used with a series of high resolution graphics adaptors When saving an image to the TGA format add the file extension tga to the end http www dimac net 25 w3 Image 2 0 Manual of its file name Example imageobj LoadImage example tga Save a 4 bit TGA image use default palette imageobj Savelmage C images example tga TGA 4 w3 Image supports 8 and 24 bit files Positive Standard format within video Negative Large file sizes ICO The Windows Icon format can be used for icons in any program You need ico files when you want to change the icons on your desktop or if you want to change the icon of an executable program on your computer An ICO file is actually a collection of bitmap like images in various pixel and color formats combined in one file Though w3 Image does not handle more than one image per ICO file w3 Image support creation of ICO files up to 256 256 pixels of size When saving an image to the ICO format add the file extension ico to the end of its file name Example imageobj LoadlImage example ico Save a 4 bit ICO image use default palette imageobj Savelmage C images example ico ICO 4 w3 Image supports 1 4 and 8 bit files Positive Standard file format for icons Negative Large file sizes WBMP Wireless Bitmap WBMP s are uncompressed black and white bitmaps that are inte
18. j StreamImage Response GIF 4 w3 Image supports 1 4 and 8 bit files Positive Generates small images when using painted images Support for transparency Negative Supports no more than 256 colors hence reduces color information when working with more than 256 colors TIFF Tagged Image File Format TIFF is a standard file format for storing images as bit maps It is used especially for scanned images because it can support any size resolution and color depth The TIFF format is a cross platform image format It is also able to store multiple images in one file This is commonly used for FAX images As a TIFF file may be a collection of images in various pixel and color formats combined in one file w3 Image does not handle more than one image per TIFF file When saving an image to the TIFF format add the file extension tif to the end of its file name Example imageobj LoadlImage example tif Save a 4 bit TIFF image use default palette imageobj Savelmage C images example tif TIF 4 w3 Image supports 1 4 8 and 24 bit files Positive A standard and a cross platform format lossless Negative Large file sizes TGA Truevision Advanced Raster Graphics Adapter TARGA Targa graphics are a standard output from Targa devices from Truevision and Pinnacle Systems These devices normally support video editing on personal computers and can be configured to take still snapshots from the video and save them
19. ject An example of the operation alphablending The illustrations show three images where a part of the second is blended with the first into a third image The colors blend into each other so the surface where the blue and the red colors overlap turns to violet Note that the second image has been stretched and the proportions have been changed Figure 5 7 You can blend images or part of images into each other Clone Clone an image object Transformation To change the dimensions of the images it must be possible for the image object to manage a set of transformation operations Stretch Specify a new size on the surface and adapt the content to the new size Scale Scale an image The image keeps its proportions Rotate Rotate an image RotateCenter Rotates the image around its center point Crop Crop an image Flip Turn the image vertically and or horisontally GrayScale Converts the image to grayscale Negative Inverts the image Threshold Converts the image into black and white specified by the threshold lightness value See figure below Brightness Adjusts image brightness Contrast Adjusts image contrast ShiftRGB Shift the images R G or B levels http www dimac net 16 w3 Image 2 0 Manual 2 zim_03 jpg 100 RGB Threshold Level ES ies Setting the Threshold level 128 makes all pixels whose R G B 3 are less than 128 turn black all else turn white Image Information Height
20. l color options supplied with the color object When creating a color object there are three different ways to describe a color value RGB as number Web Color RGB as string Web Color Name Web safe colors RGB as number RGB stands for Red Green and Blue Each color of the RGB component is described as an intensity value ranging from 0 to 255 When the values of all three components are equal the result is a shade of grey To create a color object using RGB The example describes a blue color with a red value of 2 a green value of 10 and a blue value of 245 Set colorobj imageobj CreateColorRGB 2 10 245 To receive the intensity color of each RGB value Receive the value for each intensity Receive the value for each intensity color red colorobj red Red 2 green colorobj green Green 10 blue colorobj blue Blue 245 To change an individual RGB value Change one of the individual RGB values Red is changed to 10 colorobj red 10 http www dimac net 12 w3 Image 2 0 Manual Web Color RGB as string The most common way in scripting is to define each of the intensity values in a hexadecimal form RRGGBB The color definition describes each intensity value as a hexadecimal value from 00 to FF starting with the red value followed by the green and finally the blue It is important that the RGB string starts with the sign to separate it from the string using a web color n
21. lated or converted to any electronic or machine readable form with the prior permission of Duplo Dimac Development Phone 46 42 35 94 00 Duplo AB Fax 46 42 15 80 50 Pr stgatan 12 Homepage http www dimac net E mail info dimac net rari Support support dimac net Sweden If any problems occur using this application please visit our web site http www dimac net http www dimac net 4 w3 Image 2 0 Manual Introduction Welcome to w3 Image The main purpose of w3 Image is to generate and or manipulate images w3 Image is suitable for Creating diagrams displaying data from your database Creating images for headings and buttons Automatic generation of thumbnails Creating signed images Color converting mage analysis Transforming images Converting between different image formats Performing the most common drawing operations w3 Image is an ASP compatible COM object easily integrated in your ASP solutions w3 Image can also be used in other environments such as services or Windows applications As a COM based solution it is possible to use the component in several programming languages such as C Visual Basic and other COM supported languages The object oriented structure in w3 Image makes the model straightforward to use The design has been developed to be as simple as possible to use and also to insure that the objects can be reused within the system All objects within the w3
22. ly by unregistering the w3image dll component type regsvr32 u w3image dll and then deleting the file Chapter 1 Objects The Object Model in w3 Image w3 Image consists of a set of COM objects The most important of these objects is the image object This object holds the image data that is needed to perform drawing operations The image data is like a drawing surface on which the user performs the drawing operations These operations are accomplished by using the other objects in w3 Image pens brushes fonts and colors Pens are used when managing simple image routines such as drawing lines rectangles and circles Brushes are used to fill objects with color while fonts are used to draw texts in the image w3 Image uses color objects in order to specify colors and simplify conversions between different color formats The illustration below shows an example of three image objects using different pens brushes and fonts http www dimac net 8 w3 Image 2 0 Manual Pens Image Brushes d x Note that it is possible to share the q same object a brush for example x between several image objects Image Fonts Figure 1 The Object Model Working with the Image Object The image object is the main object in w3 Image It contains the actual image data creates all other objects pens brushes fonts and colors and handles all drawing operations The image object can use one object per type at the same time That is a
23. nded for use on devices with small screens and limited bandwidth connections w3 Image support creation of WBMP files up to 127 127 pixels of size When saving an image to the WBMP format add the file extension wbmp to the end of its file name Example imageobj LoadImage C images test gif Save a 1 bit WBMP image imageobj Savelmage C images example wbmp WBMP 1 w3 Image supports 1 bit files Positive The only image format that wap pages support Negative Uncompressed doesn t support larger images than 127 127 http www dimac net 26 w3 Image 2 0 Manual Chapter 4 Transparency Transparency in w3 Image is supported by the PNG and GIF image formats The transparent color is always placed at index 0 in a palette In version 2 0 w3 Image inherits transparency and background color from the source image loaded This only applies to GIF and PNG files since they are the only one with such information Background mode The background mode can either be solid or transparent In version 1 3 and below the background mode was by default transparent In 2 0 it is only transparent when loading transparent GIF and PNG files Background color The background color is the color you define to be transparent The background color is by default set to white Consequently creating an image where the surface is white as deafult the whole image becomes transparent To make the red circle in the illustration bel
24. ow become transparent you set the background color of the image to red Figure 12 Set the background color of the image to red to make red the transparent color http www dimac net 27
25. pen a brush a font and a color can be selected at the same time But a certain pen brush font or color is used until a new pen brush font or color is selected To create an empty surface Before you can work with an image you have to create an instance of the image object To perform any later operation it is necessary that the image object has allocated image memory This is done by either creating an empty surface or by loading an image into the image object Create an instance of the image object Set imageobj Server CreateObject w3Image Image Allocate memory for a 200 400 pixels image imageobj CreateEmptySurface 200 400 To load an image The example shows how the image object loads the picture into the memory and allocates the necessary memory The width and the height of the image object will be exactly the properties of the loaded image Load an image imageobj LoadImage c test bmp To set the background properties To affect the background color and mode when creating an empty surface it is important that the mentioned properties are set before the operation of creating an empty surface This is done simply by Set mode to opaque http www dimac net 9 w3 Image 2 0 Manual imageobj bkMode 0 Set mode to transparent imageobj bkMode 1 Set background color to blue imageobj bkColor amp H000000FF amp Note that amp H00112233 amp specifies a hexadecimal value in VB S
26. ressed JPG The Joint Photographic Experts Group format JPEG is one of the most popular formats for web graphics It supports 24 bits of color information and is most commonly used for photographs and similar continuous tone bitmap images The JPEG file format stores all of the color information in an RGB image then reduces the file size by compressing it or saving only the color information that is essential to the image Most imaging applications and plug ins let you determine the amount of compression used when saving a graphic in the JPEG format When saving a file in the JPEG format add the jpg file extension to the end of its file name Example imageobj LoadlImage example jpg Note Colordepth is of no importance imageobj Savelmage mytest jpg JPG 24 w3 Image supports All JPEG s Positive Excellent when dealing with photos fast to generate and the size is small Negative Not optimal for images with few colors in terms of quality and size PNG The Portable Network Graphics format PNG will likely be the successor to the GIF file format PNG is not yet widely supported by web browsers Netscape versions 4 04 and later and Internet Explorer version 4 0b1 and later currently support this file format However PNG is expected to become a mainstream format for web images and could replace GIF entirely It is platform independent and should be used for single images only not animation Compared with GIF PNG off
27. st be set w3 Image uses as default a 9096 compression rate This could be changed as follows imageobj StreamImage Response JPG 24 10 Note that the JPG compression rate is now 10 instead of a 90 value Instead of using the fourth parameter to describe the palette function JPG uses this parameter as an input when creating and compressing the image Chapter 3 Image Formats w3 Image currently supports these image formats BMP Bitmap JPG Joint Photographic Experts Group PNG Portable Network Graphic GIF Graphics Interchange Format TIFF Tagged Image File Format TGA or TARGA Truevision Advanced Raster Graphics Adapter CO Windows Icon WBMP Wireless Bitmap BMP The Bitmap file format BMP is used for bitmap graphics Unlike other file formats which store image data from top to bottom and pixels in red green blue order the BMP format stores image data from bottom to top and pixels in blue green red order Compression of BMP files is not supported so they are usually very large When saving a file to the BMP format add the bmp file extension to the end of its file name http www dimac net 22 w3 Image 2 0 Manual Example imageobj LoadlImage example bmp Stream a 8 bit BMP image use a greyscale palette imageobj StreamImage Response BMP 8 greyscale w3 Image supports 1 4 8 and 24 bit files Positive Easy and fast to generate Negative Large files uncomp
28. stalling w3 Image To use Dimac s w3 Image you must have the w3image dll registered on your web server This is done by either running the installation program or copying the w3image dll file to your web server and manually registering it with the command regsvr32 w3image dll Any previous installations of w3 Image must first be removed as described below Before registering the w3image dll file the following files must also be copied or installed in the system32 directory cpuinf32 dll ipl dll ipla6 dll iplm35 dll http www dimac net 7 w3 Image 2 0 Manual iplm6 dll iplp6 dll iplpx dll iplw7 dll ijl1 5 dll msvcrt dll To run the installation program you must have administration permission on the web server Double click the w3image exe file to run the installation program The installation will by default install at c Program Files Dimac Development w3 Image together with manuals references and some ASP example files The installation will register the w3image dll file as a COM object Execute the ASP Example Files To better comprehend w3 Image a good idea is to run the ASP example files that come with the installation To be able to see the result of the example files they must be executed on a web server For further information about their behaviour please see the comments in the examples Uninstalling w3 Image Uninstall is available in the Add Remove Programs in your setting folders You can also do this manual
29. w3 Image 2 0 Manual w3 Image 2 0 User Manual amp http www dimac net 1 w3 Image 2 0 Manual Contents Contents eosi one veda ote sce tues ona OEE ta ban PL E ERE co RE ace EP EEE EAE bes U Du Dc MS 2 Gy TIME m 4 Totrod Cti OD me 5 Welcome to Surium 5 Wd should read this mabliadl osos oops OIM RARE riiete eE 6 How this anal 1S OEBBIZeG oet torte e otii Reese esci vo peieb o deu Eius 6 What Sy ror S ERS 6 Dried 3 IMa n c M 7 Execute the ASP Example Pes unio Egi iui aieo de Veo o sbbl ice Dn ERE aen E 8 Uninstalling W3 TS tr necheewmeacls 8 Chapter 1 ODJECIS Mer ETT 8 The Object Model in w3 Image eesesesseeseesiessesrrssrerrrsressrseresresstestertessesstesrensersresresseeee 8 Working with the Image Object ssseeseseesessresseseeesersresressttsrsrrsserseesrrssreserseresresseseess 9 To cr ate an empty iuro e E E 9 dd TREES aese R EE O EE E R 9 To set the background properties sesseeseeseesessesstseresressrserestesstserertessetstestenserseesreeseese 9 Working with Pensar TH 10 To create and select a pen object nnn snesssessnssessseeersetssseessressereseresseressresseesseessee 10 Styles Of PENS Me c aaa a 11 Working with Brushes P 11 To create and select a brush OBIEel uuscen gene pr Et REM RN UN EE UG xp dtes 11 Workin uide cp 11 To cre
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