ImageConvertRow

Converts a row of image data into another color depth

Syntax

Declare Sub ImageConvertRow ( ByVal src As Any Ptr, ByVal src_bpp As Integer, ByVal dst As Any Ptr, ByVal dst_bpp As Integer, ByVal width As Integer, ByVal isrgb As Integer = 1 )

Usage

ImageConvertRow( src, src_bpp, dst, dst_bpp, width [, isrgb ] )

Parameters

src

The address of the start of the source row. The source can either be a full-color image with a bit depth of 24 or 32 bits per pixel, or a paletted image with a bit depth of 1-8 bits per pixel. Converting a paletted image will only work properly if you are in a screen mode that is using the correct palette for the image when you do the conversion.

src_bpp

The number of bits per pixel in the source row. 1-8, 24 and 32.

dst

The address of the start of the destination row. The image can be a full-color image of 16 or 32 bits per pixel. If the source is a paletted image, the destination can also be a paletted image of 1 to 8 bits per pixel.

dst_bpp

The number of bits per pixel in the destination row. Valid values for this are 1-8, 16 and 32.

width

The length of the row in pixels.

isrgb

A value of zero indicates that the Red and Blue channels are the other way round in the source image. Use this switch if you want the Red and Blue channels to be swapped in the conversion.

Description

Copies the row of an image from one memory location to another, converting the color information in each pixel to match the destination image.

Example

#include "fbgfx.bi" #if __FB_LANG__ = "fb" Using FB #endif Const As Integer w = 64, h = 64 Dim As IMAGE Ptr img8, img32 Dim As Integer x, y '' create a 32-bit image, size w*h: ScreenRes 1, 1, 32, , GFX_NULL img32 = ImageCreate(w, h) If img32 = 0 Then Print "Imagecreate failed on img32!": Sleep: End '' create an 8-bit image, size w*h: ScreenRes 1, 1, 8, , GFX_NULL img8 = ImageCreate(w, h) If img8 = 0 Then Print "Imagecreate failed on img8!": Sleep: End '' fill 8-bit image with a pattern For y = 0 To h - 1 For x = 0 To w - 1 PSet img8, (x, y), 56 + (x + y) Mod 24 Next x Next y '' open a graphics window in 8-bit mode, and PUT the image into it: ScreenRes 320, 200, 8 WindowTitle "8-bit color mode" Put (10, 10), img8 Sleep '' copy the image data into a 32-bit image Dim As Byte Ptr p8, p32 Dim As Integer pitch8, pitch32 #ifndef ImageInfo '' older versions of FB don't have the ImageInfo feature #define GETPITCH(img_) IIf(img_->Type=PUT_HEADER_NEW,img_->pitch,img_->old.width*img_->old.bpp) #define GETP(img_) CPtr(Byte Ptr,img_)+IIf(img_->Type=PUT_HEADER_NEW,SizeOf(PUT_HEADER),SizeOf(_OLD_HEADER)) pitch8 = GETPITCH(img8): p8 = GETP(img8) pitch32 = GETPITCH(img32): p32 = GETP(img32) #else ImageInfo( img8, , , , pitch8, p8 ) ImageInfo( img32, , , , pitch32, p32 ) #endif For y = 0 To h - 1 ImageConvertRow(@p8 [ y * pitch8 ], 8, _ @p32[ y * pitch32], 32, _ w) Next y '' open a graphics window in 32-bit mode and PUT the image into it: ScreenRes 320, 200, 32 WindowTitle "32-bit color mode" Put (10, 10), img32 Sleep '' free the images from memory: ImageDestroy img8 ImageDestroy img32

Dialect Differences

Not available in the -lang qb dialect unless referenced with the alias __ImageConvertRow.

Differences from QB

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