在 ARM 9 板上显示图像 [英] Displaying an image on ARM 9 board
问题描述
我需要在嵌入式系统上显示图像.板卡配置如下:
I need to display images on an embedded system. The board configuration is as follows:
它是 AT91sam9263-EK，上面运行着 Linux 2.6.20 内核.有没有这个板子的图像处理库.处理器是ARM926EJ-S.
It is AT91sam9263-EK, with Linux 2.6.20 kernel running on it. Are there any image processing libraries for this board.The processor is ARM926EJ-S.
谢谢大家
推荐答案
如果在 Linux 操作系统中没有激活帧缓冲区，我知道它在 Linux4Sam.您可以随时尝试通过发出命令 cat/bin/sh > 来激活它./dev/fb0;屏幕上应该会出现一个随机图案(请注意，可能需要激活背光 - 如果关闭它，您可能根本看不到任何东西).您可能必须先终止在目标上运行的图形环境.
If the framebuffer isn't activated in the Linux OS you got I know that it is in the Linux OS provided by Linux4Sam. You can always try if it is activated by issuing the command cat /bin/sh > /dev/fb0; a random pattern should appear on the screen (note that it might be necessary to activate the backlight - if it is turned off you might not see anything at all). You might have to kill the graphical environment that is running on target first.
如果您只想显示图像，则可以通过打开帧缓冲区 (/dev/fb0) 并写入(或只是 cat)来实现；但您必须拥有正确格式的图像.如果我没记错的话，评估板中的帧缓冲区是 RGB555(即红色 5 位，绿色 5 位，蓝色 5 位).
If all you want to do is to display an image it is possible to do that by opening the framebuffer (/dev/fb0) and write to it (or just cat it); but you have to have an image in the correct format. If I remember correctly the framebuffer in the evaluation board is a RGB555 (i.e. 5 bits for red, 5 bits for green and 5 bits for blue).
如果您想使用 GUI 库，您必须使用具有帧缓冲区后端的库.在标准 Linux 系统上，GUI 库假定您安装了 X，但其中一些也有帧缓冲区后端.例如 Qt 可以以这种方式编译(但我认为您必须修改它以提供正确的颜色信息；它只支持开箱即用的 RGB565).DirectFB 是一个更简单的解决方案，提供基本的图形支持(但它支持 FreeType，为您提供良好的字体支持).有关其他示例，请参阅上面提供的链接.
If you want to use a GUI library you have to use one that has a framebuffer backend. On a standard Linux system a GUI library assumes that you have X installed but some of them also have framebuffer backends. Qt for instance can be compiled in such a way (but I think you have to modify it to provide the correct color information; it only supports RGB565 out of the box). DirectFB is a simpler solution that provides basic graphic support (but it has support for FreeType giving you good font support). See the links provided above for other examples.
这篇关于在 ARM 9 板上显示图像的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！
