addImage method

Adds a print command for HTML5 Canvas image data to the command buffer.

Converts the specified area of an HTML5 Canvas RGBA full-color image into raster image data according to the color mode setting by the addImage method as well as halftone property and brightness property setting. One pixel of an image corresponds to one dot of the printer, and when a transparent color is contained in the image, the background of the image is assumed to be white.

Syntax

	addImage(context, x, y, width, height, color, mode);

Parameter

context

Value	Description
context	Specifies 2D context of HTML5 Canvas.

x

Value	Description
Integer from 0 to 65535	Specifies the horizontal start position of the print area.

y

Value	Description
Integer from 0 to 65535	Specifies the vertical start position of the print area.

width

Value	Description
Integer from 0 to 65535	Specifies the width of the print area.

height

Value	Description
Integer from 0 to 65535	Specifies the height of the print area.

color

Value	Description
COLOR_NONE	No printing
COLOR_1 (default)	First color
COLOR_2	Second color
COLOR_3	Third color
COLOR_4	Fourth color
undefined	Not specify.

mode

Value	Description
MODE_MONO	Monochrome (2 scales)
MODE_GRAY16	Multi-gradation (16 scales)
undefined	Monochrome (2 scales)

Return value

Return value	Object type
Printer object	Printer
HybridPrinter2 object	HybridPrinter2

Exception

Exception	Object type
Parameter " ... " is invalid	Error

Supplementary explanation

HTML5 Canvas data containing image data downloaded from different domains cannot be printed. A security error occurs due to the Same-Origin policy of JavaScript.
Multi-gradation printing can be used in the standard mode but not in the page mode.
In order to print a image data at a high speed, set the parameter constant of addTextAlign method to ALIGN_LEFT and the width parameter of the addImage method to a multiple of 8 which does not exceed the sheet width of the printer.
In the page mode, because image data is printed at the current print position with the lower-left dot of the image data as the reference point, the print position does not move.

Quick Access

[Name]
[Format]
[Range]
[Description]
[Notes]

Epson ePOS SDK includes patented or patent pending functions. The contents must not be disclosed to third parties.

Epson ePOS SDK for JavaScript

Introduction
help
ePOSDevice object
Common to device objects
- callEvent method
OtherPeripheral object
- send method
- onreceive event
Display object
Keyboard object
POSKeyboard object
- onkeypress event
MSR object
- ondata event
Printer object
HybridPrinter2 object
Scanner object
- ondata event
SimpleSerial object
- sendCommand
- oncommandreply event
GermanyFiscalElement object
- operate method
- ongfereceive event
DeviceHubTerminal object
- shutdown method
- restart method
CommBoxManager object
- openCommBox method
- closeCommBox method
CommBox object
ePosDeviceConfiguration object
- Constructor
- getRegisterdDevices method
Appendix
- Error Code List
  - Error Codes acquired in the Callback Parameter and Counteractions
  - Error Codes acquired in the Onreceive Event and Countermeasure
- Key code list
- List of Supported Objects
- List of Supported APIs
- Printer-specific Support Information
  - TM-m10
  - TM-m30
  - TM-m30II
  - TM-m30II-H
  - TM-m30II-NT
  - TM-m30II-S
  - TM-m30II-SL
  - TM-m30III
  - TM-m30III-H
  - TM-m50
  - TM-m50II
  - TM-m50II-H
  - TM-T20II
  - TM-T20III
  - TM-T82III
  - TM-T88VI
  - TM-T88VII
  - TM-L100
  - TM-T70
  - TM-T70II
  - TM-T88IV
  - TM-T88V
  - TM-U220
  - TM-U220II
  - TM-U330
  - TM-P20
  - TM-P20II
  - TM-P60II (Receipt)
  - TM-P60II (Peeler)
  - TM-P80
  - TM-P80II
  - TM-H6000V
  - TM-T20II-i
  - TM-T70-i
  - TM-T82II-i
  - TM-T83II-i
  - TM-T88V-i
  - TM-T88VI-iHUB
  - TM-U220-i
  - TM-U220IIB-i
  - TM-T70II-DT
  - TM-T70II-DT2
  - TM-T88V-DT
  - TM-T88VI-DT2
  - TM-H6000IV-DT
  - TM-T20
  - TM-T82II
  - TM-T83II
  - TM-T90
  - TM-L90
  - TM-H6000IV
- Usage restriction by firmware version