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Qt Built-in color exchange bit: red and blue

I am using QtEmbedded (4.8.0) on an ARM display device with a color depth of 16 bits on a framebuffer (/ dev / fb0). In this scenario, we get the colors of the RED and BLUE bits.

We use the following compiled flags:

./configure -embedded arm -xplatform qws/linux-arm-gnueabi-g++ -prefix /home/rchaves/Toolchain -release -opensource -shared -fast -depths 16 -largefile -no-exceptions -no-accessibility -stl -no-sql-mysql -no-sql-psql -no-sql-oci -no-sql-odbc -no-sql-tds -no-sql-db2 -no-sql-sqlite -no-sql-sqlite2 -no-sql-ibase -no-qt3support -no-xmlpatterns -no-multimedia -no-audio-backend -no-phonon-backend -no-svg -no-webkit -no-javascript-jit -no-script -no-scripttools -no-declarative -no-declarative-debug -qt-zlib -qt-libtiff -qt-libpng -qt-libmng -qt-libjpeg -no-openssl -no-nis -no-cups -iconv -no-pch -no-dbus -qt-freetype -no-opengl -qt-gfx-linuxfb -qt-kbd-linuxinput -qt-mouse-tslib -nomake demos -nomake examples

And the following parameters to run the application:

QWS_DISPLAY=LinuxFb:/dev/fb0:depth=16 ./app -qws

Here is the application framebuffer log (samples):

The framebuffer device was opened successfully.

Fixed screen info:
    id:          DISP3 BG
    smem_start:  0x93800000
    smem_len:    7864320
    type:        0
    type_aux:    0
    visual:      2
    xpanstep:    1
    ypanstep:    1
    ywrapstep:   0
    line_length: 2048
    mmio_start:  0x0
    mmio_len:    0
    accel:       0

The framebuffer device was mapped to memory successfully.

Successfully switched to graphics mode.

Variable screen info:
    xres:           1024
    yres:           768
    xres_virtual:   1024
    yres_virtual:   3840
    yoffset:        0
    xoffset:        0
    bits_per_pixel: 16
    grayscale: 0
    red:    offset:  0, length:  5, msb_right:  0
    green:  offset:  5, length:  6, msb_right:  0
    blue:   offset: 11, length:  5, msb_right:  0
    transp: offset:  0, length:  0, msb_right:  0
    nonstd:       0
    activate:     64
    height:       -1
    width:        -1
    accel_flags:  0x0
    pixclock:     15385
    left_margin:  157
    right_margin: 157
    upper_margin: 16
    lower_margin: 15
    hsync_len:    5
    vsync_len:    1
    sync:         0
    vmode:        0

Frame Buffer Performance test...
    Average:   43020 usecs
    Bandwidth: 174.338 MByte/Sec
    Max. FPS:  23.245 fps

Will draw 3 rectangles on the screen,
they should be colored red, green and blue (in that order).
Done.
+5
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2 answers

Better late than never. I had this exact problem with a SAM5 processor using Qt5.5.1 and the linuxfb plugin. Reconfigure or recompile the Qt5 structure DOES NOT SOLVE the problem.

-, LinuxFB BGR. open error, . determineFormat ../src/plugins/platforms/linuxfb/qlinuxfbscreen.cpp, , ImageFormats ** RGB , .

, patch, , .

"", , RBG. . , swapRgb, .

+1

. -depths generic ./configure -display linuxfb:genericcolors. , .

: , .

littleendian . - linux fb .

0

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