On Tue, 27 Jan 2009, Mark Jackson wrote:
This patch adds 16bpp BMP support to the common lcd code.
Use CONFIG_BMP_16BPP and set LCD_BPP to LCD_COLOR16 to enable the code.
At the moment it's only been tested on the MIMC200 AVR32 board, but extending this to other platforms should be a simple task !!
Signed-off-by: Mark Jackson mpfj@mimc.co.uk
It is a pity I didn't notice these patches earlier, and I didn't notice them, because it's only today that I realized that I needed to change this code too. But - for the other case 8 bit bmp on a 16 bit lcd without a colourmap support. I have implemented that, it works now, a patch will follow, but while working on it I noticed how this generic code is difficult to work with due to all the ifdefs and especially platform-specific types and code. So, looking at this your patch - do we really need the one more CONFIG_ define for CONFIG_BMP_16BPP? What are the drawbacks of adding your code unconditionally? extra 100 bytes for all configurations using LCD?
Another question - do you really need 16bpp bmp? I saw a discussion on this list, that other picture formats should not be added to U-Boot - you can easily convert any format to bmp. Are 256 colours really not enough for you? I used a real photo today as a test image, converted to an 8-bit bmp. It looked well enough on my qvga. And normally you use this lcd code to display a splashscreen, which is usually a computer-generated image, so 256 colours should suffice? Although, I am not an expert in graphical desing.
If we really add more bmp formats, we also get more combinations like of bmp / lcd:
BMP LCD 1-bit 1-bit 8-bit 1-bit 16-bit 1-bit 1-bit 8-bit ...
if we really want to go that way, maybe better break this code into several functions for different format conversions?
Thanks Guennadi --- Guennadi Liakhovetski, Ph.D.
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