_SAVEIMAGE
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_SAVEIMAGE saves the contents of an image or screen page to an image file.
Syntax
- _SAVEIMAGE fileName$[, imageHandle&][, requirements$]
Parameters
- fileName$ is literal or variable STRING file name value.
- Optional imageHandle& is a LONG image handle or a valid screen page number.
- Optional requirements$ STRING values can be:
- BMP: Saves the image as Windows Bitmap if no file extension is specified.
- GIF: Saves the image as Graphics Interchange Format if no file extension is specified.
- HDR: Saves the image as Radiance HDR if no file extension is specified.
- ICO: Saves the image as Windows Icon if no file extension is specified.
- JPG: Saves the image as Joint Photographic Experts Group if no file extension is specified.
- PNG: Saves the image as Portable Network Graphics if no file extension is specified.
- QOI: Saves the image as Quite OK Image if no file extension is specified.
- TGA: Saves the image as Truevision TARGA if no file extension is specified.
Description
- fileName$ extension name takes precedence over requirements$
- If no file extension is specified in fileName$ and no format is specified in requirements$, then the PNG format is used by default.
- If imageHandle& is omitted then the image handle returned by _DISPLAY (function) is used.
- Efforts are made to save the image in the highest quality possible using 32-bit RGBA format, ensuring that alpha channel information is retained whenever the format permits.
- Due to the inherent limitations of GIFs, these images are stored in an 8-bit indexed format, which results in a reduction of quality and color detail.
- Windows ICO files utilize the PNG specification, which enables the storage of images exceeding 256x256 pixels in size.
- SCREEN 0 (text mode) screens and "images" can be saved. Text surfaces are rendered internally using the master QB64-PE VGA fonts prior to saving.
Availability
none
v3.9.0
yes
yes
yes
- ICO and GIF support was added in QB64-PE v3.14.0.
Examples
- Example 1
- It's possible to use _SAVEIMAGE with text screens.
- This demo draws a Mandelbrot in SCREEN 0 and then saves the screen as a .jpg image.
OPTION _EXPLICIT CONST X_MIN = -2! CONST X_MAX = 1! CONST Y_MIN = -1! CONST Y_MAX = 1! CONST MAX_ITER = 100 CONST PIX_CHAR = 48 SCREEN 0 WIDTH 160, 100 _FONT 8 DIM w AS LONG: w = _WIDTH DIM h AS LONG: h = _HEIGHT DIM maxX AS LONG: maxX = w - 1 DIM maxY AS LONG: maxY = h - 1 DIM y AS LONG: FOR y = 0 TO maxY DIM x AS LONG: FOR x = 0 TO maxX DIM cx AS SINGLE: cx = X_MIN + (x / w) * (X_MAX - X_MIN) DIM cy AS SINGLE: cy = Y_MIN + (y / h) * (Y_MAX - Y_MIN) DIM zx AS SINGLE: zx = 0 DIM zy AS SINGLE: zy = 0 DIM i AS LONG: i = 0 DO UNTIL zx * zx + zy * zy >= 4 OR i >= MAX_ITER DIM temp AS SINGLE: temp = zx * zx - zy * zy + cx zy = 2 * zx * zy + cy zx = temp i = i + 1 LOOP COLOR i MOD 16 _PRINTSTRING (x + 1, y + 1), CHR$(PIX_CHAR) NEXT x NEXT y _SAVEIMAGE "TextMandelbrot!.jpg" END |
- Example 2
- Saving a graphics image to a .png file. This is much like example one. However, it renders the graphics to an 8-bit offscreen image and then passes the image handle to _SAVEIMAGE.
OPTION _EXPLICIT CONST X_MIN = -2! CONST X_MAX = 1! CONST Y_MIN = -1! CONST Y_MAX = 1! CONST MAX_ITER = 100 DIM img AS LONG: img = _NEWIMAGE(640 * 2, 400 * 2, 256) _DEST img DIM w AS LONG: w = _WIDTH DIM h AS LONG: h = _HEIGHT DIM maxX AS LONG: maxX = w - 1 DIM maxY AS LONG: maxY = h - 1 DIM y AS LONG: FOR y = 0 TO maxY DIM x AS LONG: FOR x = 0 TO maxX DIM cx AS SINGLE: cx = X_MIN + (x / maxX) * (X_MAX - X_MIN) DIM cy AS SINGLE: cy = Y_MIN + (y / maxY) * (Y_MAX - Y_MIN) DIM zx AS SINGLE: zx = 0 DIM zy AS SINGLE: zy = 0 DIM i AS LONG: i = 0 DO UNTIL zx * zx + zy * zy >= 4 OR i >= MAX_ITER DIM temp AS SINGLE: temp = zx * zx - zy * zy + cx zy = 2 * zx * zy + cy zx = temp i = i + 1 LOOP PSET (x, y), (i MOD 16) * 16 + (i MOD 8) NEXT x NEXT y _SAVEIMAGE "Mandelbrot", img _DEST 0 PRINT "Saved image." END |